Sample records for laboratory ball lightning

  1. Laboratory-produced ball lightning

    NASA Astrophysics Data System (ADS)

    Golka, Robert K., Jr.

    1994-05-01

    For 25 years I have actively been searching for the true nature of ball lightning and attempting to reproduce it at will in the laboratory. As one might expect, many unidentified lights in the atmosphere have been called ball lightning, including Texas Maffa lights (automobile headlights), flying saucers (UFOs), swamp gas in Ann Arbor, Michigan, etc. For 15 years I thought ball lightning was strictly a high-voltage phenomenon. It was not until 1984 when I was short-circuiting the electrical output of a diesel electric railroad locomotive that I realized that the phenomenon was related more to a high current. Although I am hoping for some other types of ball lightning to emerge such as strictly electrostatic-electromagnetic manifestations, I have been unlucky in finding laboratory provable evidence. Cavity-formed plasmodes can be made by putting a 2-inch burning candle in a home kitchen microwave oven. The plasmodes float around for as long as the microwave energy is present.

  2. Science of Ball Lightning (Fire Ball)

    NASA Astrophysics Data System (ADS)

    Ohtsuki, Yoshi-Hiko

    1989-08-01

    The Table of Contents for the full book PDF is as follows: * Organizing Committee * Preface * Ball Lightning -- The Continuing Challenge * Hungarian Ball Lightning Observations in 1987 * Nature of Ball Lightning in Japan * Phenomenological and Psychological Analysis of 150 Austrian Ball Lightning Reports * Physical Problems and Physical Properties of Ball Lightning * Statistical Analysis of the Ball Lightning Properties * A Fluid-Dynamical Model for Ball Lightning and Bead Lightning * The Lifetime of Hill's Vortex * Electrical and Radiative Properties of Ball Lightning * The Candle Flame as a Model of Ball Lightning * A Model for Ball Lightning * The High-Temperature Physico-Chemical Processes in the Lightning Storm Atmosphere (A Physico-Chemical Model of Ball Lightning) * New Approach to Ball Lightning * A Calculation of Electric Field of Ball Lightning * The Physical Explanation to the UFO over Xinjiang, Northern West China * Electric Reconnection, Critical Ionization Velocity, Ponderomotive Force, and Their Applications to Triggered and Ball Lightning * The PLASMAK™ Configuration and Ball Lightning * Experimental Research on Ball Lightning * Performance of High-Voltage Test Facility Designed for Investigation of Ball Lightning * List of Participants

  3. An investigation of the generation and properties of laboratory-produced ball lightning

    NASA Astrophysics Data System (ADS)

    Oreshko, A. G.

    2015-06-01

    The experiments revealed that ball lightning is a self-confining quasi-neutral in a whole plasma system that rotates around its axis. Ball lightning has a structure of a spherical electric domain, consisting of a kernel with excess negative charge and an external spherical layer with excess positive charge. The excess of charges of one sort and the lack of charges of the other sort in the kernel or in the external spherical layer significantly reduces the possibility of electron capture by means of an electric field, created by the nearest ions and leads to a drastic slowdown of recombination process. Direct proof has been obtained that inside of ball lightning - in an external spherical layer that rotates around the axis - there is a circular current of sub-relativistic particles. This current creates and maintains its own poloidal magnetic field of ball lightning, i.e. it carries out the function of magnetic dynamo. The kernel of ball lightning is situated in a region with minimum values of induction of the magnetic field. The inequality of positive and negative charges in elements of ball lightning also significantly reduces losses of the charged plasma on bremsstrahlung. Ball lightning generation occurs in a plasmic vortex. The ball lightning energy in the region of its generation significantly differs from the ball lightning energy, which is drifting in space. The axial component of kinetic energy of particles slightly exceeds 100 keV and the rotational component of the ions energy is a bit greater than 1 MeV. Ball lightning is `embedded' in atmosphere autonomous accelerator of charged particles of a cyclotron type due to self-generation of strong crossed electric and magnetic fields. A discussion of the conditions of stability and long-term existence of ball lightning is given.

  4. Relativistic-microwave theory of ball lightning.

    PubMed

    Wu, H-C

    2016-06-22

    Ball lightning, a fireball sometimes observed during lightnings, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a lightning stroke reaching the ground, a relativistic electron bunch can be produced, which in turn excites intense microwave radiation. The latter ionizes the local air and the radiation pressure evacuates the resulting plasma, forming a spherical plasma bubble that stably traps the radiation. This mechanism is verified by particle simulations. The many known properties of ball lightning, such as the occurrence site, relation to the lightning channels, appearance in aircraft, its shape, size, sound, spark, spectrum, motion, as well as the resulting injuries and damages, are also explained. Our theory suggests that ball lighting can be created in the laboratory or triggered during thunderstorms. Our results should be useful for lightning protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics.

  5. Relativistic-microwave theory of ball lightning

    NASA Astrophysics Data System (ADS)

    Wu, H.-C.

    2016-06-01

    Ball lightning, a fireball sometimes observed during lightnings, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a lightning stroke reaching the ground, a relativistic electron bunch can be produced, which in turn excites intense microwave radiation. The latter ionizes the local air and the radiation pressure evacuates the resulting plasma, forming a spherical plasma bubble that stably traps the radiation. This mechanism is verified by particle simulations. The many known properties of ball lightning, such as the occurrence site, relation to the lightning channels, appearance in aircraft, its shape, size, sound, spark, spectrum, motion, as well as the resulting injuries and damages, are also explained. Our theory suggests that ball lighting can be created in the laboratory or triggered during thunderstorms. Our results should be useful for lightning protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics.

  6. Relativistic-microwave theory of ball lightning

    PubMed Central

    Wu, H.-C.

    2016-01-01

    Ball lightning, a fireball sometimes observed during lightnings, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a lightning stroke reaching the ground, a relativistic electron bunch can be produced, which in turn excites intense microwave radiation. The latter ionizes the local air and the radiation pressure evacuates the resulting plasma, forming a spherical plasma bubble that stably traps the radiation. This mechanism is verified by particle simulations. The many known properties of ball lightning, such as the occurrence site, relation to the lightning channels, appearance in aircraft, its shape, size, sound, spark, spectrum, motion, as well as the resulting injuries and damages, are also explained. Our theory suggests that ball lighting can be created in the laboratory or triggered during thunderstorms. Our results should be useful for lightning protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics. PMID:27328835

  7. A general theory for ball lightning structure and light output

    NASA Astrophysics Data System (ADS)

    Morrow, R.

    2018-03-01

    A general theory for free-floating ball lightning is presented which unifies the phantom plasma ball theory involving the production of very little light, with theories for ball lightning involving light output produced by burning particles from the soil. The mechanism for the formation of plasma balls is shown to be quite general, producing very similar plasma balls independent of initial ion densities over four orders of magnitude. All that is required is an excess of positive ions in the initial ball of ions. The central plasma density after 1 s is shown to be the reciprocal of the ion neutralization coefficient for all cases, both analytically and computationally. Further, the plasma region has zero electric field in all cases. Surrounding the plasma ball is a sphere of positive ions moving away from the centre via their own space-charge field; this space-charge field, which is the same in all cases near the plasma ball, drives negative ions and negative particles towards the plasma centre. The connection with burning particle theories is the proposition that the burning particles are highly-charged which is very likely after a lightning strike. Burning negatively charged particles would be driven into the plasma ball region and trapped while any positively charged particles would be driven away. The plasma ball structure is shown to last more than 10 s and the ‘burnout time’ for a typical coal particle (as an example) has been measured at 5-10 s this is comparable with the lifetimes observed for ball lightning. The light output from a few hundred particles is estimated to be ~1 W, a typical output for ball lightning. Finally, suggestions are made for the generation of ball lightning in the laboratory.

  8. Ball Lightning in Zero Gravity in the Laboratory

    NASA Astrophysics Data System (ADS)

    Alexeff, Igor; Parameswaran, Sriram; Grace, Michael

    2004-11-01

    We have created balls of orange plasma in atmospheric - pressure air that survive for over 1/2 second without power input. The technique used was to create a pulsed horizontal electric arc in a zero - gravity environment using 6 neon - sign transformers in parallel, each producing 16,000 V at 60 mA. The zero - gravity environment reduces heat losses by reducing thermal convection, creating a larger ball. Previous work (1) suggests that the ball lifetime scales as the square of the ball radius. The balls were photographed after power turnoff with a high - speed 16 mm movie camera. Movies of the balls being formed and decaying will be shown. We suggest that there are several other forms of ball lightning (2). 1.Igor Alexeff et. al. International Conference On Plasma Science, Jeju, Korea, June 2-5, 2003, Conference Record, p 254. 2. Igor Alexeff and Mark Rader, IEEE Transactions on Plasma Science, Vol. 20, No. 6, Dec. 1992, pp.669-671. Igor Alexeff and Mark Rader, Fusion Technology, Vol. 27, May 1995, p. 271.

  9. Ball lightning from atmospheric discharges via metal nanosphere oxidation: from soils, wood or metals.

    PubMed

    Abrahamson, John

    2002-01-15

    The slow (diffusion-limited) oxidation of metal nanoparticles has previously been proposed as the mechanism for ball lightning energy release, and argued to be the result of a normal lightning strike on soil. Here this basic model of networked nanoparticles is detailed further, and extended to lightning strikes on metal structures, and also to the action of other storm-related discharges or man-made discharges. The basic model predicted the important properties of "average" observed ball lightning, and the extension in this paper also covers high-energy examples of ball lightning. Laboratory checks of the theory are described, and predictions given of what conditions are necessary for observing ball lightning in the laboratory. Key requirements of the model are a sheltered region near the strike foot and starting materials which can generate a metal vapour under intensive heating, including soil, wood or a metal structure. The evolution of hydrocarbons (often plastics) along with metal vapour can ensure the local survival of the metal vapour even in an oxidizing atmosphere. Subsequent condensation of this vapour to metallic nanoparticles in networks provides the coherence of a ball structure, which also releases light over an extended time. Also discussed is the passage of ball lightning through a sheet of building material, including glass, and its occasional charring of flesh on close contact.

  10. James L. Tuck Los Alamos ball lightning pioneer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baker, D.A.

    1999-07-01

    James Tuck was well known for starting the Project Sherwood group at Los Alamos Scientific Laboratory in 1952. This group was formed to study and develop concepts for controlled fusion energy. In his later years after retiring from Controlled Fusion Division, he continued research at Los Alamos on the topic of ball lightning. He traveled widely giving lectures on both observations of others and his own experimental efforts. He collected anecdotal observations obtained from those in his lecture audiences during his travels and from responses from newspaper articles where he asked for specific information from ball lightning observers. He finallymore » cut off this collection of data when the number of responses became overwhelming. The author's primary publication on ball lightning was a short laboratory report. He planned on publishing a book on the subject but this was never completed before his death. Tuck focused his experimental effort on attempting to duplicate the production of plasma balls claimed to be observed in US Navy submarines when a switch was opened under overload conditions with battery power. During lunch breaks he made use of a Los Alamos N-division battery bank facility to mock up a submarine power pack and switch gear. This non-funded effort was abruptly terminated when an explosion occurred in the facility. An overview of Tuck's research and views will be given. The flavor Jim's personality as well as a ball produced with his experimental apparatus will be shown using video chips.« less

  11. An early record of ball lightning: Oliva (Spain), 1619

    NASA Astrophysics Data System (ADS)

    Domínguez-Castro, Fernando

    2018-05-01

    In a primary documentary source we found an early record of ball lightning (BL), which was observed in the monastery of Pi (Oliva, southeastern Spain) on 18 October 1619. The ball lightning was observed by at least three people and was described as a rolling burning vessel and a ball of fire. The ball lightning appeared following a lightning flash, showed a mainly horizontal motion, crossed a wall, smudged an image of the Lady of Rebollet (then known as Lady of Pi) and burnt her ruff, and overturned a cross.

  12. A self-similar magnetohydrodynamic model for ball lightnings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsui, K. H.

    2006-07-15

    Ball lightning is modeled by magnetohydrodynamic (MHD) equations in two-dimensional spherical geometry with azimuthal symmetry. Dynamic evolutions in the radial direction are described by the self-similar evolution function y(t). The plasma pressure, mass density, and magnetic fields are solved in terms of the radial label {eta}. This model gives spherical MHD plasmoids with axisymmetric force-free magnetic field, and spherically symmetric plasma pressure and mass density, which self-consistently determine the polytropic index {gamma}. The spatially oscillating nature of the radial and meridional field structures indicate embedded regions of closed field lines. These regions are named secondary plasmoids, whereas the overall self-similarmore » spherical structure is named the primary plasmoid. According to this model, the time evolution function allows the primary plasmoid expand outward in two modes. The corresponding ejection of the embedded secondary plasmoids results in ball lightning offering an answer as how they come into being. The first is an accelerated expanding mode. This mode appears to fit plasmoids ejected from thundercloud tops with acceleration to ionosphere seen in high altitude atmospheric observations of sprites and blue jets. It also appears to account for midair high-speed ball lightning overtaking airplanes, and ground level high-speed energetic ball lightning. The second is a decelerated expanding mode, and it appears to be compatible to slowly moving ball lightning seen near ground level. The inverse of this second mode corresponds to an accelerated inward collapse, which could bring ball lightning to an end sometimes with a cracking sound.« less

  13. Ball lightning dynamics and stability at moderate ion densities

    NASA Astrophysics Data System (ADS)

    Morrow, R.

    2017-10-01

    A general mechanism is presented for the dynamics and structure of ball lightning and for the maintenance of the ball lightning structure for several seconds. Results are obtained using a spherical geometry for air at atmospheric pressure, by solving the continuity equations for electrons, positive ions and negative ions coupled with Poisson’s equation. A lightning strike can generate conditions in the lightning channel with a majority of positive nitrogen ions, and a minority of negative oxygen ions and electrons. The calculations are initiated with electrons included; however, at the moderate ion densities chosen the electrons are rapidly lost to form negative ions, and after 1 µs their influence on the ion dynamics is negligible. Further development after 1 µs is followed using a simpler set of equations involving only positive ions and negative ions, but including ion diffusion. The space-charge electric field generated by the majority positive ions drives them from the centre of the distribution and drives the minority negative ions and electrons towards the centre of the distribution. In the central region the positive and negative ion distributions eventually overlap exactly and their space-charge fields cancel resulting in zero electric field, and the plasma ball formed is quite stable for a number of seconds. The formation of such plasma balls is not critically dependent on the initial diameter of the ion distributions, or the initial density of minority negative ions. The ion densities decrease relatively slowly due to mutual neutralization of positive and negative ions. The radiation from this neutralization process involving positive nitrogen ions and negative oxygen ions is not sufficient to account for the reported luminosity of ball lightning and some other source of luminosity is shown to be required; the plasma ball model used could readily incorporate other ions in order to account for the luminosity and range of colours reported for ball

  14. MODEL TESTS ON BALL LIGHTNING; Modellversuche zum Kugelblitz

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    nauer, H.

    1959-10-31

    Ball lightning phenomena and properties gleaned from a collection of observations are examined. The observations of a diffusion combustion of minute gas admixtures in air are thoroughly examined because they display the greatest resemblance to natural ball lightning. A comparison of properties with the qualities of the luminous clouds during diffusion combustion shows very good agreement. (W.D.M.)

  15. Extreme ball lightning event of August 6, 1868 in County Donegal, Ireland.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    VanDevender, J. Pace; McGinley, Niall; van Doorn, Peter

    2008-04-01

    Although laboratory experiments have produced glowing balls of light that fade in <1 s after external power is removed and theories have been proposed to explain low-energy events, energetic ball lightning is not understood. A seminal event that illuminates the fundamental nature of ball lightning is needed to advance our understanding of the phenomenon. We report such a seminal event: the energetic ball lightning event of August 6, 1868, in County Donegal, Ireland, extensively reported to the Royal Society by M. Fitzgerald. It lasted for 20 minutes, left a 6 m square hole and a 100 m long by 1.2more » m deep trench, tore away a 25 m long and 1.5 m deep stream bank that diverted the course of the stream, and terminated by producing a shallow cave in the opposite bank of the stream. We found and characterized the site and show that the geomorphology and carbon dating support the account by M. Fitzgerald. We find that the excavation is not consistent with chemical, nuclear, or electrostatic forces but is consistent with Analysis of the event and the local conditions in 2006 is consistent with magnetic induction at {approx} 1 MHz frequency expelling the moderately conductive, water saturated peat down to the underlying clay/rock layer. The 60-cm diameter--which diminished to 10 cm diameter without reducing the impact of the ball lightning on the environment--and the size of the depressions, the yield strength of the peat, and the lack of any mention of smoke or steam in Fitzgerald's report would be consistent with the core of the ball lightning being a magnetically levitated mini black hole weighing more than 20,000 kg. The results suggest that such energetic ball lightning should be detectable at great distances by its electromagnetic emissions, which might provide a characteristic signature to reveal the source of the energy and the equilibrium configuration of the contained currents. Unexplained intermittent emissions in the MHz range are necessary but not

  16. Study on the luminous characteristics of a natural ball lightning

    NASA Astrophysics Data System (ADS)

    Wang, Hao; Yuan, Ping; Cen, Jianyong; Liu, Guorong

    2018-02-01

    According to the optical images of the whole process of a natural ball lightning recorded by two slit-less spectrographs in the Qinghai plateau of China, the simulated observation experiment on the luminous intensity of the spherical light source was carried out. The luminous intensity and the optical power of the natural ball lightning in the wavelength range of 400-690 nm were estimated based on the experimental data and the Lambert-Beer Law. The results show that the maximum luminous intensity was about 1.24 × 105 cd in the initial stage of the natural ball lightning, and the maximum luminous intensity and the maximum optical power in most time of its life were about 5.9 × 104 cd and 4.2 × 103 W, respectively.

  17. The similarities between the hallucinations associated with the partial epileptic seizures of the occipital lobe and ball lightning observations

    NASA Astrophysics Data System (ADS)

    Cooray, G. K.; Cooray, V.

    2007-12-01

    Ball Lightning was seen and described since antiquity and recorded in many places. Ball lightning is usually observed during thunderstorms but large number of ball lightning observations is also reported during fine weather without any connection to thunderstorms or lightning. However, so far no one has managed to generate them in the laboratory. It is photographed very rarely and in many cases the authenticity of them is questionable. It is possible that many different phenomena are grouped together and categorized simply as ball lightning. Indeed, the visual hallucinations associated with simple partial epileptic seizures, during which the patient remains conscious, may also be categorized by a patient unaware of his or her condition as ball lightning observation. Such visual hallucinations may occur as a result of an epileptic seizure in the occipital, temporo-occipital or temporal lobes of the cerebrum [1,2,3]. In some cases the hallucination is perceived as a coloured ball moving horizontally from the periphery to the centre of the vision. The ball may appear to be rotating or spinning. The colour of the ball can be red, yellow, blue or green. Sometimes, the ball may appear to have a solid structure surrounded by a thin glow or in other cases the ball appears to generate spark like phenomena. When the ball is moving towards the centre of the vision it may increase its intensity and when it reaches the centre it can 'explode' illuminating the whole field of vision. During the hallucinations the vision is obscured only in the area occupied by the apparent object. The hallucinations may last for 5 to 30 seconds and rarely up to a minute. Occipital seizures may spread into other regions of the brain giving auditory, olfactory and sensory sensations. These sensations could be buzzing sounds, the smell of burning rubber, pain with thermal perception especially in the arms and the face, and numbness and tingling sensation. In some cases a person may experience only

  18. How to create ball lightning

    NASA Technical Reports Server (NTRS)

    Golka, Robert K., Jr.

    1991-01-01

    Procedures are given on how to produce ball lightning. Necessary equipment includes a transformer of 150,000 watts capable of providing approximately 10,000 amperes at 15 volts, 60 cycles; thick one inch cables of stranded wire leading into a 3 by 4 by 1 foot plastic tank; a quarter inch thick 4 by 6 inch aluminum plate to be used as one of the discharge electrodes; and another electrode of heavy copper wire with the insulation stripped back 6 inches.

  19. Some of the ball lightning observations could be phosphenes induced by energetic radiation from thunderstorms and lightning

    NASA Astrophysics Data System (ADS)

    Cooray, G. K.; Cooray, G. V.; Dwyer, J. R.

    2011-12-01

    Ball Lightning was seen and described since antiquity and recorded in many places. However, so far no one has managed to generate them in the laboratory. It is possible that many different phenomena are grouped together and categorized simply as ball lightning. One such phenomenon could be the phosphenes induced in humans by energetic radiation and particles from lightning and thunderstorms. A phosphene is a visual sensation that is characterized by perceiving luminous phenomena without light entering the eye. Phosphenes are generated when electrical signals are created in the retina or the optical nerve by other means in the absence of light stimuli. The fact that energetic radiation produced by radium can give rise to phosphenes was first noted by Giesel in 1899 [1]. A resurge of studies related to the creation of phosphenes by energetic radiation took place after the reports of phosphenes observed in space by Apollo astronauts and first reported by Buzz Aldrin after the Apollo 11 flight to the moon in 1969 [2]. The shapes of the phosphenes observed by astronauts were either rods, comet shaped, or comprised of a single dot, several dots or blobs. The colors were mostly white, but some had been colored yellow, orange, blue, green or red. The majority of the astronauts had perceived some kind of motion in association with the phosphenes. Most of the time, they were moving horizontally (from the periphery of the vision to the center) and sometimes diagonally, but never vertically. Subsequent studies conducted in space and ground confirmed the creation of phosphenes by energetic radiation. From these studies the threshold energy dissipation in the eye tissue necessary for phosphenes induction was estimated to be 10 MeV/cm. In the present study a quantitative analysis of the energetic radiation generated in the form of X-rays, Gamma rays and relativistic electrons by thunderstorms and lightning was made to investigate whether this radiation is strong enough to induce

  20. A Ball Lightning Model as a Possible Explanation of Recently Reported Cavity Lights

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fryberger, David; /SLAC

    The salient features of cavity lights, in particular, mobile luminous objects (MLO's), as have been experimentally observed in superconducting accelerator cavities, are summarized. A model based upon standard electromagnetic interactions between a small particle and the 1.5 GHz cavity excitation field is described. This model can explain some features of these data, in particular, the existence of particle orbits without wall contact. While this result is an important success for the model, it is detailed why the model as it stands is incomplete. It is argued that no avenues for a suitable extension of the model through established physics appearmore » evident, which motivates an investigation of a model based upon a more exotic object, ball lightning. As discussed, further motivation derives from the fact that there are significant similarities in many of the qualitative features of ball lightning and MLO's, even though they appear in quite different circumstances and differ in scale by orders of magnitude. The ball lightning model, which incorporates electromagnetic charges and currents, is based on a symmetrized set of Maxwell's equations in which the electromagnetic sources and fields are characterized by a process called dyality rotation. It is shown that a consistent mathematical description of dyality rotation as a physical process can be achieved by adding suitable (phenomenological) current terms to supplement the usual current terms in the symmetrized Maxwell's equations. These currents, which enable the conservation of electric and magnetic charge, are called vacuum currents. It is shown that the proposed ball lightning model offers a good qualitative explanation of the perplexing aspects of the MLO data. Avenues for further study are indicated.« less

  1. Are perytons signatures of ball lightning?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dodin, I. Y.; Fisch, N. J.

    2014-10-20

    The enigmatic downchirped signals, called 'perytons', that are detected by radio telescopes in the GHz frequency range may be produced by an atmospheric phenomenon known as ball lightning (BL). If BLs act as nonstationary radio frequency cavities, their characteristic emission frequencies and evolution timescales are consistent with peryton observations, and so are general patterns in which BLs are known to occur. Based on this evidence, testable predictions are made that can confirm or rule out a causal connection between perytons and BLs. In either case, how perytons are searched for in observational data may warrant reconsideration because existing procedures maymore » be discarding events that have the same nature as known perytons.« less

  2. Sources and components of ball lightning theory

    NASA Astrophysics Data System (ADS)

    Nikitin, A. I.; Bychkov, V. L.; Nikitina, T. F.; Velichko, A. M.; Abakumov, V. I.

    2018-03-01

    The article describes the cases when ball lightning (BL) exhibited an extremely high specific energy store (up to 1010 J/m3), a presence of uncompensated electric charge (up to 10‑3 C) and an ability to generate high frequency pulses (up to 10 MW). It is shown that the realization of a combination of these properties of BL is possible if to consider it as a heterogeneous system consisting of a unipolarly charged core and a dielectric shell. In the electric field of the core charge, arises a force owing to the polarization of the shell that opposes the Coulomb repulsion force of the charges. BL models constructed according to the indicated principle are described: the electrodynamic model and the chemical-thermal model, which treats BL as a hollow sphere filled with steam. The requirement to take into account the main three properties of BL makes it possible to reduce the number of models of this natural phenomenon. Detailed cases of observations of high-energy lightning are analyzed.

  3. An Analysis of Ball Lightning-Aircraft Incidents

    NASA Astrophysics Data System (ADS)

    Doe, R. K.; Keul, A. G.; Bychkov, V.

    2009-12-01

    Lightning is a rare but regular phenomenon for air traffic. Research and design have created aircraft that withstand average lightning strikes. Ball lightning (BL), a metastable, rare lightning type, is also observed from (and within) aircraft. Science and the media focused on individual BL incidents and did not analyze general patterns. Lacking established incident reporting channels, most BL observations are still passed on as “aviation lore”. To overcome this unsatisfactory condition, the authors collected and analyzed an international data bank of 87 BL-aircraft case histories from 1938 to 2007. 37 Russian military and civil BL reports were provided by the third author. Of the whole sample, 36 (41%) cases occurred over Russia/RF/SU, 24 (28%) over USA/Canada, 23 (26%) over Europe, and 4 (5%) over Asia/Pacific. Various types of military (US: C-54/141, B-52, KC-97/135 Stratotankers, C130, P-3 Orion, RF/SU: PO-2, IL, SU, TU, MIG; Nimrod, Saab-105) and civilian aircraft (US: DC-3/6, Metroliner, B-727/737/757/777, RF/SU: AN, TU; VC-10, Fokker F-28, CRJ-200), as well as general aviation (C-172, Falcon-20), were involved. BL reports show a flat annual April to August maximum. At BL impact, 15 aircraft were climbing, 7 descending; most were at cruising altitude. 42 (48%) reported BL outside the aircraft, 37 (43%) inside, 7 (8%) both in-and outside. No damage was reported in 34 (39%) cases, 39 objects (45%) caused minor damage, 11 major damage (13%), 3 even resulted in military aircraft losses. 3 objects caused minor, 1 major crew injury. 23 damage cases were associated with BL inside the fuselage; all 4 crew injury cases were of that BL type. Mean size is described as 25 cm, sometimes over 1 m, color 30% in the yellow-red, 10% in the blue-green spectral region, 8% white, duration around 10 seconds, sometimes over 1 minute. 33 (38%) incidents ended with an explosion of the object. Thunderstorm conditions were reported by 25 (29%) of the observers, 9 (10%) said there

  4. Solid charged-core model of ball lightning

    NASA Astrophysics Data System (ADS)

    Muldrew, D. B.

    2010-01-01

    In this study, ball lightning (BL) is assumed to have a solid, positively-charged core. According to this underlying assumption, the core is surrounded by a thin electron layer with a charge nearly equal in magnitude to that of the core. A vacuum exists between the core and the electron layer containing an intense electromagnetic (EM) field which is reflected and guided by the electron layer. The microwave EM field applies a ponderomotive force (radiation pressure) to the electrons preventing them from falling into the core. The energetic electrons ionize the air next to the electron layer forming a neutral plasma layer. The electric-field distributions and their associated frequencies in the ball are determined by applying boundary conditions to a differential equation given by Stratton (1941). It is then shown that the electron and plasma layers are sufficiently thick and dense to completely trap and guide the EM field. This model of BL is exceptional in that it can explain all or nearly all of the peculiar characteristics of BL. The ES energy associated with the core charge can be extremely large which can explain the observations that occasionally BL contains enormous energy. The mass of the core prevents the BL from rising like a helium-filled balloon - a problem with most plasma and burning-gas models. The positively charged core keeps the negatively charged electron layer from diffusing away, i.e. it holds the ball together; other models do not have a mechanism to do this. The high electrical charges on the core and in the electron layer explains why some people have been electrocuted by BL. Experiments indicate that BL radiates microwaves upon exploding and this is consistent with the model. The fact that this novel model of BL can explain these and other observations is strong evidence that the model should be taken seriously.

  5. Characterization and Infrared Emission Spectroscopy of Ball Plasmoid Discharges

    NASA Astrophysics Data System (ADS)

    Dubowsky, Scott E.; McCall, Benjamin J.

    2015-06-01

    Plasmas at atmospheric pressure serve many purposes, from ionization sources for ambient mass spectrometry (AMS) to plasma-assisted wound healing. Of the many naturally occurring ambient plasmas, ball lightning is one of the least understood; there is currently no solid explanation in the literature for the formation and lifetime of natural ball lightning. With the first measurements of naturally occurring ball lightning being reported last year, we have worked to replicate the natural phenomenon in order to elucidate the physical and chemical processes by which the plasma is sustained at ambient conditions. We are able to generate ball-shaped plasmoids (self-sustaining plasmas) that are analogous to natural ball lightning using a high-voltage, high-current, pulsed DC system. Improvements to the discharge electronics used in our laboratory and characterization of the plasmoids that are generated from this system will be described. Infrared emission spectroscopy of these plasmoids reveals emission from water and hydroxyl radical -- fitting methods for these molecular species in the complex experimental spectra will be presented. Rotational temperatures for the stretching and bending modes of H2O along with that of OH will be presented, and the non-equilibrium nature of the plasmoid will be discussed in this context. Cen, J.; Yuan, P,; Xue, S. Phys. Rev. Lett. 2014, 112, 035001. Dubowsky, S.E.; Friday, D.M.; Peters, K.C.; Zhao, Z.; Perry, R.H.; McCall, B.J. Int. J. Mass Spectrom. 2015, 376, 39-45.

  6. Laboratory-Scale Evidence for Lightning-Mediated Gene Transfer in Soil

    PubMed Central

    Demanèche, Sandrine; Bertolla, Franck; Buret, François; Nalin, Renaud; Sailland, Alain; Auriol, Philippe; Vogel, Timothy M.; Simonet, Pascal

    2001-01-01

    Electrical fields and current can permeabilize bacterial membranes, allowing for the penetration of naked DNA. Given that the environment is subjected to regular thunderstorms and lightning discharges that induce enormous electrical perturbations, the possibility of natural electrotransformation of bacteria was investigated. We demonstrated with soil microcosm experiments that the transformation of added bacteria could be increased locally via lightning-mediated current injection. The incorporation of three genes coding for antibiotic resistance (plasmid pBR328) into the Escherichia coli strain DH10B recipient previously added to soil was observed only after the soil had been subjected to laboratory-scale lightning. Laboratory-scale lightning had an electrical field gradient (700 versus 600 kV m−1) and current density (2.5 versus 12.6 kA m−2) similar to those of full-scale lightning. Controls handled identically except for not being subjected to lightning produced no detectable antibiotic-resistant clones. In addition, simulated storm cloud electrical fields (in the absence of current) did not produce detectable clones (transformation detection limit, 10−9). Natural electrotransformation might be a mechanism involved in bacterial evolution. PMID:11472916

  7. Technique for the comparison of light spectra from natural and laboratory generated lightning current arcs

    NASA Astrophysics Data System (ADS)

    Mitchard, D.; Clark, D.; Carr, D.; Haddad, A.

    2016-08-01

    A technique was developed for the comparison of observed emission spectra from lightning current arcs generated through self-breakdown in air and the use of two types of initiation wire, aluminum bronze and nichrome, against previously published spectra of natural lightning events. A spectrograph system was used in which the wavelength of light emitted by the lightning arc was analyzed to derive elemental interactions. A lightning impulse of up to 100 kA was applied to a two hemispherical tungsten electrode configuration which allowed the effect of the lightning current and lightning arc length to be investigated. A natural lightning reference spectrum was reconstructed from literature, and generated lightning spectra were obtained from self-breakdown across a 14.0 mm air gap and triggered along initiation wires of length up to 72.4 mm. A comparison of the spectra showed that the generated lightning arc induced via self-breakdown produced a very similar spectrum to that of natural lightning, with the addition of only a few lines from the tungsten electrodes. A comparison of the results from the aluminum bronze initiation wire showed several more lines, whereas results from the nichrome initiation wire differed greatly across large parts of the spectrum. This work highlights the potential use for spectrographic techniques in the study of lightning interactions with surrounding media and materials, and in natural phenomena such as recently observed ball lightning.

  8. Technique for the comparison of light spectra from natural and laboratory generated lightning current arcs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mitchard, D., E-mail: mitcharddr@cardiff.ac.uk; Clark, D.; Carr, D.

    A technique was developed for the comparison of observed emission spectra from lightning current arcs generated through self-breakdown in air and the use of two types of initiation wire, aluminum bronze and nichrome, against previously published spectra of natural lightning events. A spectrograph system was used in which the wavelength of light emitted by the lightning arc was analyzed to derive elemental interactions. A lightning impulse of up to 100 kA was applied to a two hemispherical tungsten electrode configuration which allowed the effect of the lightning current and lightning arc length to be investigated. A natural lightning reference spectrum wasmore » reconstructed from literature, and generated lightning spectra were obtained from self-breakdown across a 14.0 mm air gap and triggered along initiation wires of length up to 72.4 mm. A comparison of the spectra showed that the generated lightning arc induced via self-breakdown produced a very similar spectrum to that of natural lightning, with the addition of only a few lines from the tungsten electrodes. A comparison of the results from the aluminum bronze initiation wire showed several more lines, whereas results from the nichrome initiation wire differed greatly across large parts of the spectrum. This work highlights the potential use for spectrographic techniques in the study of lightning interactions with surrounding media and materials, and in natural phenomena such as recently observed ball lightning.« less

  9. Ball-joint grounding ring

    NASA Technical Reports Server (NTRS)

    Aperlo, P. J. A.; Buck, P. A.; Weldon, V. A.

    1981-01-01

    In ball and socket joint where electrical insulator such as polytetrafluoroethylene is used as line to minimize friction, good electrical contact across joint may be needed for lightning protection or to prevent static-charge build-up. Electrical contact is maintained by ring of spring-loaded fingers mounted in socket. It may be useful in industry for cranes, trailers, and other applications requiring ball and socket joint.

  10. Ball Lightning–Aerosol Electrochemical Power Source or A Cloud of Batteries

    PubMed Central

    2007-01-01

    Despite numerous attempts, an adequate theoretical and experimental simulation of ball lightning still remains incomplete. According to the model proposed here, the processes of electrochemical oxidation within separate aerosol particles are the basis for this phenomenon, and ball lightning is a cloud of composite nano or submicron particles, where each particle is a spontaneously formed nanobattery which is short-circuited by the surface discharge because it is of such a small size. As free discharge-shorted current loops, aerosol nanobatteries are exposed to a powerful mutual magnetic dipole–dipole attraction. The gaseous products and thermal energy produced by each nanobattery as a result of the intra-particle self-sustaining electrochemical reactions, cause a mutual repulsion of these particles over short distances and prevent their aggregation, while a collectivization of the current loops of separate particles, due to the electric arc overlapping between adjacent particles, weakens their mutual magnetic attraction over short distances. Discharge currents in the range of several amperes to several thousand amperes as well as the pre-explosive mega ampere currents, generated in the reduction–oxidation reactions and distributed between all the aerosol particles, explain both the magnetic attraction between the elements of the ball lightning substance and the impressive electromagnetic effects of ball lightning.

  11. Ball lightning passage through a glass without breaking it

    NASA Astrophysics Data System (ADS)

    Bychkov, Vladimir L.; Nikitin, Anatoly I.; Ivanenko, Ilia P.; Nikitina, Tamara F.; Velichko, Alexander M.; Nosikov, Igor A.

    2016-12-01

    In long history of ball lightning (BL) theory development there is a struggle of two concepts. According to the first one, BL - is a high frequency electrical discharge, burning in the air due to action of alternating electric field or a continuous current generated by an external source of energy. According to the second one, the BL is a material body, storing energy within itself. Data banks of BL observations give evidence that BL can pass through glasses, leaving no traces on them. Supporters of the first concept consider this as the proof of the correctness of the "electric field" BL nature. Representation of BL as a material body with internal source of energy explains most of its features, but has difficulties in explanation of BL penetration through glasses. We describe results of research of the glass, through which BL freely passed, that was observed by one of the authors. They proved the presence of traces left by BL. With a help of optical and scanning microscopes and laser beam probing of the glass, that experienced action of 20 cm BL, we have found traces in it: in the glass we found a region of 1-2 mm, at the center of which a cavity of 0.24 mm diameter is located. This gives evidence to a "material" nature of BL. BL possibility to pass through small holes and its ability to "make" such holes poses a number of difficult issues to researchers indicated in the article.

  12. Laboratory demonstration of lightning strike pattern on different roof tops installed with Franklin Rods

    NASA Astrophysics Data System (ADS)

    Ullah, Irshad; Baharom, MNR; Ahmed, H.; Luqman, HM.; Zainal, Zainab

    2017-11-01

    Protection against lightning is always a challenging job for the researcher. The consequences due to lightning on different building shapes needs a comprehensive knowledge in order to provide the information to the common man. This paper is mainly concern with lightning pattern when it strikes on the building with different shape. The work is based on the practical experimental work in high voltage laboratory. Different shapes of the scaled structures have been selected in order to investigate the equal distribution of lightning voltage. The equal distribution of lightning voltage will provide the maximum probability of lightning strike on air terminal of the selected shapes. Building shapes have a very important role in lightning protection. The shapes of the roof tops have different geometry and the Franklin rod installation is also varies with changing the shape of the roof top. According to the ambient weather condition of Malaysia high voltage impulse is applied on the lightning rod installed on different geometrical shape. The equal distribution of high voltage impulse is obtained as the geometry of the scaled structure is identical and the air gap for all the tested object is kept the same. This equal distribution of the lightning voltage also proves that the probability of lightning strike is on the corner and the edges of the building structure.

  13. Emission Spectroscopy of Atmospheric-Pressure Ball Plasmoids: Higher Energy Reveals a Rich Chemistry

    NASA Astrophysics Data System (ADS)

    Dubowsky, Scott E.; Rose, Amber Nicole; Glumac, Nick; McCall, Benjamin J.

    2017-06-01

    Ball plasmoids (self-sustaining spherical plasmas) are a particularly unique example of a non-equilibrium air plasma. These plasmoids have lifetimes on the order of hundreds of milliseconds without an external power source, however, current models dictate that a ball plasmoid should recombine in a millisecond or less. Ball plasmoids are considered to be a laboratory analogue of natural ball lightning, a phenomenon that has eluded scientific explanation for centuries. We are searching for the underlying physicochemical mechanism(s) by which ball plasmoids and (by extension) ball lightning are stabilized using a variety of diagnostic techniques. This presentation will focus on optical emission spectroscopy (OES) of ball plasmoid discharges between 190-850 nm. The previous generation of OES measurements of this system showed emission from only a few atomic and molecular species, however, the energy available for the discharges in these experiments was limited by the size of the capacitor banks and voltages to which the capacitor banks were charged. We are capable of generating plasmoids at much higher energies, and as a result we are the first to report a very rich chemistry previously not observed in ball plasmoids. We have identified signals from species including NO A^{2}Σ^{+}→X^{2}Π, OH A^{2}Σ^{+}→X^{2}Π, NH A^{3}Π→X^{3}Σ^{-}, AlO A^{2}Π→X^{2}Σ^{+}, NH^{+} B^{2}Δ→X^{2}Π, W I, Al I, Cu I, and H_{α}, all of which have not yet been reported for this system. Analysis of the emission spectra and fitting procedures will be discussed, rotational temperatures of constituent species will be reported, and theories of ball plasmoid stabilization based upon these new results will be presented. Versteegh, A.; Behringer, K.; Fantz, U.; Fussman, G.; Jüttner, B.; Noack, S. Plas. Sour. Sci. Technol. 2008, 17(2), 024014 Stephan, K. D.; Dumas, S.; Komala-Noor, L.; McMinn, J. Plas. Sour. Sci. Technol. 2013, 22(2), 025018

  14. The physics of lightning

    NASA Astrophysics Data System (ADS)

    Dwyer, Joseph R.; Uman, Martin A.

    2014-01-01

    of upward connecting leaders from those objects or from the ground? What is the physics of compact intra-cloud discharges (CIDs) (that produce a narrow bipolar wideband electric field pulse, a narrow bipolar event or NBE, apparently multiple-reflecting propagating waves within 1 km height, and copious HF and VHF radiation)? How are CIDs related to other types of preliminary breakdown pulses? Are CIDs related to the Terrestrial Gamma-Ray Flashes (TGFs) observed on orbiting satellites or to the Transient Luminous Events (TLEs) photographed above cloud tops, particularly to so-called “gigantic jets”? By what physical mechanisms do lightning leaders emit pulses of X-rays? Do the X-rays play a role in lightning propagation? By what mechanism do thunderclouds generate relatively-steady internal X-rays? Do X-rays and other high energy radiation affect cloud electrification and play a role in lightning initiation? By what physical mechanisms are Terrestrial Gamma-Ray Flashes (TGFs) produced? Do TGFs pose a hazard to individuals in aircraft? How do cloud-to-ground and intra-cloud lightning affect the upper atmosphere and ionosphere? What are the physics of the Transient Luminous Events (TLEs), “Sprites”, “jets”, and “elves”? What is the energy input into the ionosphere/magnetosphere from lightning? How exactly does rocket-and-wire (“classical” with a grounded wire and “altitude” with a floating wire) triggering of lightning work? Are there other possible and practical triggering techniques such as laser triggering? Can triggering reduce or eliminate the local occurrence of natural lightning? What are the power and energy of the component processes of lightning flashes and how are they distributed among electromagnetic processes (DC to light), thermal processes, mechanical (acoustic) processes, and relativistic (high energy) processes (runaway electrons, runaway positrons, X-ray, and gamma rays)? What is the physics of ball lightning? Is there more than

  15. Measurements of Ozone, Lightning, and Electric Fields within Thunderstorms over Langmuir Laboratory, New Mexico

    NASA Astrophysics Data System (ADS)

    Eack, K. B.; Winn, W. P.; Rust, W. D.; Minschwaner, K.; Fredrickson, S.; Kennedy, D.; Edens, H. E.; Kalnajs, L. E.; Rabin, R. M.; Lu, G. P.; Bonin, D.

    2008-12-01

    A field project was conducted at the Langmuir Laboratory for Atmospheric Research during the summer of 2008 in an effort to better understand the direct production of ozone within electrically active storms. Five balloon flights were successfully launched into thunderstorms during this project. In situ measurements from the balloon instrument package included ozone mixing ratio, electric field strength, meteorological variables, and GPS location and timing. Lightning discharges were identified within each storm using a ground based lightning mapping array. The data show that the instruments ascended through regions of high electric fields within the sampled storms, and in some cases the balloon was in very close proximity to lightning. Relationships between electric field, lightning, and ozone observed during these flights will be discussed.

  16. Observations of Ball-Lightning-Like Plasmoids Ejected from Silicon by Localized Microwaves.

    PubMed

    Meir, Yehuda; Jerby, Eli; Barkay, Zahava; Ashkenazi, Dana; Mitchell, James Brian; Narayanan, Theyencheri; Eliaz, Noam; LeGarrec, Jean-Luc; Sztucki, Michael; Meshcheryakov, Oleg

    2013-09-11

    This paper presents experimental characterization of plasmoids (fireballs) obtained by directing localized microwave power (<1 kW at 2.45 GHz) onto a silicon-based substrate in a microwave cavity. The plasmoid emerges up from the hotspot created in the solid substrate into the air within the microwave cavity. The experimental diagnostics employed for the fireball characterization in this study include measurements of microwave scattering, optical spectroscopy, small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Various characteristics of these plasmoids as dusty plasma are drawn by a theoretical analysis of the experimental observations. Aggregations of dust particles within the plasmoid are detected at nanometer and micrometer scales by both in - situ SAXS and ex-situ SEM measurements. The resemblance of these plasmoids to the natural ball-lightning (BL) phenomenon is discussed with regard to silicon nano-particle clustering and formation of slowly-oxidized silicon micro-spheres within the BL. Potential applications and practical derivatives of this study (e.g., direct conversion of solids to powders, material identification by breakdown spectroscopy (MIBS), thermite ignition, and combustion) are discussed.

  17. Observations of Ball-Lightning-Like Plasmoids Ejected from Silicon by Localized Microwaves

    PubMed Central

    Meir, Yehuda; Jerby, Eli; Barkay, Zahava; Ashkenazi, Dana; Mitchell, James Brian; Narayanan, Theyencheri; Eliaz, Noam; LeGarrec, Jean-Luc; Sztucki, Michael; Meshcheryakov, Oleg

    2013-01-01

    This paper presents experimental characterization of plasmoids (fireballs) obtained by directing localized microwave power (<1 kW at 2.45 GHz) onto a silicon-based substrate in a microwave cavity. The plasmoid emerges up from the hotspot created in the solid substrate into the air within the microwave cavity. The experimental diagnostics employed for the fireball characterization in this study include measurements of microwave scattering, optical spectroscopy, small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Various characteristics of these plasmoids as dusty plasma are drawn by a theoretical analysis of the experimental observations. Aggregations of dust particles within the plasmoid are detected at nanometer and micrometer scales by both in-situ SAXS and ex-situ SEM measurements. The resemblance of these plasmoids to the natural ball-lightning (BL) phenomenon is discussed with regard to silicon nano-particle clustering and formation of slowly-oxidized silicon micro-spheres within the BL. Potential applications and practical derivatives of this study (e.g., direct conversion of solids to powders, material identification by breakdown spectroscopy (MIBS), thermite ignition, and combustion) are discussed. PMID:28788315

  18. Lightning Protection Certification for High Explosives Facilities at Lawrence Livermore National Laboratory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clancy, T J; Brown, C G; Ong, M M

    2006-01-11

    Presented here is an innovation in lighting safety certification, and a description of its implementation for high explosives processing and storage facilities at Lawrence Livermore National Laboratory. Lightning rods have proven useful in the protection of wooden structures; however, modern structures made of rebar, concrete, and the like, require fresh thinking. Our process involves a rigorous and unique approach to lightning safety for modern buildings, where the internal voltages and currents are quantified and the risk assessed. To follow are the main technical aspects of lightning protection for modern structures and these methods comply with the requirements of the Nationalmore » Fire Protection Association, the National Electrical Code, and the Department of Energy [1][2]. At the date of this release, we have certified over 70 HE processing and storage cells at our Site 300 facility.« less

  19. Lightning Protection

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Lightning Technologies, Inc., Pittsfield, MA, - a spinoff company founded by president J. Anderson Plumer, a former NASA contractor employee who developed his expertise with General Electric Company's High Voltage Laboratory - was a key player in Langley Research Center's Storm Hazards Research Program. Lightning Technologies used its NASA acquired experience to develop protective measures for electronic systems and composite structures on aircraft, both of which are particularly susceptible to lightning damage. The company also provides protection design and verification testing services for complete aircraft systems or individual components. Most aircraft component manufacturers are among Lightning Technologies' clients.

  20. Modern concepts of treatment and prevention of lightning injuries.

    PubMed

    Edlich, Richard F; Farinholt, Heidi-Marie A; Winters, Kathryne L; Britt, L D; Long, William B

    2005-01-01

    Lightning is the second most common cause of weather-related death in the United States. Lightning is a natural atmospheric discharge that occurs between regions of net positive and net negative electric charges. There are several types of lightning, including streak lightning, sheet lightning, ribbon lightning, bead lightning, and ball lightning. Lightning causes injury through five basic mechanisms: direct strike, flash discharge (splash), contact, ground current (step voltage), and blunt trauma. While persons struck by lightning show evidence of multisystem derangement, the most dramatic effects involve the cardiovascular and central nervous systems. Cardiopulmonary arrest is the most common cause of death in lightning victims. Immediate resuscitation of people struck by lightning greatly affects the prognosis. Electrocardiographic changes observed following lightning accidents are probably from primary electric injury or burns of the myocardium without coronary artery occlusion. Lightning induces vasomotor spasm from direct sympathetic stimulation resulting in severe loss of pulses in the extremities. This vasoconstriction may be associated with transient paralysis. Damage to the central nervous system accounts for the second most debilitating group of injuries. Central nervous system injuries from lightning include amnesia and confusion, immediate loss of consciousness, weakness, intracranial injuries, and even brief aphasia. Other organ systems injured by lightning include the eye, ear, gastrointestinal system, skin, and musculoskeletal system. The best treatment of lightning injuries is prevention. The Lightning Safety Guidelines devised by the Lightning Safety Group should be instituted in the United States and other nations to prevent these devastating injuries.

  1. An Integrated 0-1 Hour First-Flash Lightning Nowcasting, Lightning Amount and Lightning Jump Warning Capability

    NASA Technical Reports Server (NTRS)

    Mecikalski, John; Jewett, Chris; Carey, Larry; Zavodsky, Brad; Stano, Geoffrey; Chronis, Themis

    2015-01-01

    Using satellite-based methods that provide accurate 0-1 hour convective initiation (CI) nowcasts, and rely on proven success coupling satellite and radar fields in the Corridor Integrated Weather System (CIWS; operated and developed at MIT-Lincoln Laboratory), to subsequently monitor for first-flash lightning initiation (LI) and later period lightning trends as storms evolve. Enhance IR-based methods within the GOES-R CI Algorithm (that must meet specific thresholds for a given cumulus cloud before the cloud is considered to have an increased likelihood of producing lightning next 90 min) that forecast LI. Integrate GOES-R CI and LI fields with radar thresholds (e.g., first greater than or equal to 40 dBZ echo at the -10 C altitude) and NWP model data within the WDSS-II system for LI-events from new convective storms. Track ongoing lightning using Lightning Mapping Array (LMA) and pseudo-Geostationary Lightning Mapper (GLM) data to assess per-storm lightning trends (e.g., as tied to lightning jumps) and outline threat regions. Evaluate the ability to produce LI nowcasts through a "lightning threat" product, and obtain feedback from National Weather Service forecasters on its value as a decision support tool.

  2. What Initiates Lightning?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    Lightning is an energetic electric discharge, creating a current that flows briefly within a cloud--or between a cloud and the ground--and heating the air to temperatures about five times hotter than the sun’s surface. But there’s a lot about lightning that’s still a mystery. Los Alamos National Laboratory is working to change that. Because lightning produces optical and radio frequency signals similar to those from a nuclear explosion, it’s important to be able to distinguish whether such signals are caused by lightning or a nuclear event. As part of the global security mission at Los Alamos, scientists use lightning tomore » help develop better instruments for nuclear test-ban treaty monitoring and, in the process, have learned a lot about lightning itself.« less

  3. Laboratory simulations of volcanic ash charging and conditions for volcanic lightning on Venus

    NASA Astrophysics Data System (ADS)

    Airey, Martin; Warriner-Bacon, Elliot; Aplin, Karen

    2017-04-01

    Lightning may be important in the emergence of life on Earth and elsewhere, as significant chemical reactions occur in the superheated region around the lightning channel. This, combined with the availability of phosphates in volcanic clouds, suggests that volcanic lightning could have been the catalyst for the formation of biological compounds on the early Earth [1]. In addition to meteorological lightning, volcanic activity also generates electrical discharges within charged ash plumes, which can be a significant contributor to atmospheric electricity on geologically active planets. The physical properties of other planetary atmospheres, such as that of Venus, have an effect on the processes that lead to the generation of volcanic lightning. Volcanism is known to have occurred on Venus in the past, and recent observations made by ESA's Venus Express satellite have provided evidence for currently active volcanism [2-4], and lightning discharges [e.g. 5]. Venusian lightning could potentially be volcanic in origin, since no meteorological mechanisms are known to separate charge effectively in its clouds [6]. The hunt for further evidence for lightning at Venus is ongoing, for example by means of the Lightning and Airglow Camera (LAC) [7] on Akatsuki, the current JAXA mission at Venus. Our laboratory experiments simulate ash generation and measure electrical charging of the ash under typical atmospheric conditions on Earth and Venus. The study uses a 1 litre chamber, which, when pressurised and heated, can simulate the high-pressure, high-temperature, carbon dioxide-dominated atmosphere of Venus at 10 km altitude ( 5 MPa, 650 K). A key finding of previous work [8] is that ash plume-forming eruptions are more likely to occur at higher altitudes such as these on Venus. The chamber contains temperature/pressure monitoring and logging equipment, a rock collision apparatus (based on [9]) to generate the charged rock fragments, and charge measurement electrodes connected

  4. Voss with Bonner Ball Neutron Detector Control Unit in Destiny laboratory

    NASA Image and Video Library

    2001-03-23

    ISS002-E-5714 (23 March 2001) --- Astronaut James S. Voss, Expedition Two flight engineer, sets up the Bonner Ball Neutron Detector (BBND) in the Destiny laboratory. The BBND is connected to the Human Research Facility (HRF). This image was recorded with a digital still camera.

  5. The physics of charge separation preceding lightning strokes in thunderclouds

    NASA Technical Reports Server (NTRS)

    Kyrala, Ali

    1987-01-01

    The physics of charge separation preceding lightning strokes in thunderclouds is presented by three types of arguments: An explanation is given for the aggregation of electrical charges of like sign overcoming Coulomb repulsion by attraction due to exchange interaction. The latter is well known in quantum mechanics from the theories of the nuclear bond and the covalent bond. A classical electrostatic model of charge balls of segregated positive and negative charges in the thundercloud is presented. These charge balls can only be maintained in temporarily stable locations by a containing vortex. Because they will be of different sizes and masses, they will stabilize at different altitudes when drag forces are included with the given electrostatic force. The question of how the charges become concentrated again after lightning discharges is approached by means of the collisional Boltzmann transport equation to explain quasi-periodic recharging. It is shown that solutions cannot be separable in both position and time if they are to represent aggregation.

  6. Lightning Technology (Supplement)

    DTIC Science & Technology

    1981-01-01

    material presented in this report was taken from a variety of sources; therefore, various units of measure are used. Use of trade names or names of...Clifford, and W. G. Butters 3. IMPLEMENTATION AND EXPERIENCE WITH LIGHTNING HARDENING MEASURES ON THE NAVY/AIR FORCE COMBAT MANEUVERING RANGES...overall lightning event taken from an appropriate base of wideband measurements . In 1979, the Air Force Wright Aeronautical Laboratories began a joint

  7. Estimates of the Lightning NOx Profile in the Vicinity of the North Alabama Lightning Mapping Array

    NASA Technical Reports Server (NTRS)

    Koshak, William J.; Peterson, Harold S.; McCaul, Eugene W.; Blazar, Arastoo

    2010-01-01

    The NASA Marshall Space Flight Center Lightning Nitrogen Oxides Model (LNOM) is applied to August 2006 North Alabama Lightning Mapping Array (NALMA) data to estimate the (unmixed and otherwise environmentally unmodified) vertical source profile of lightning nitrogen oxides, NOx = NO + NO2. Data from the National Lightning Detection Network (Trademark) (NLDN) is also employed. This is part of a larger effort aimed at building a more realistic lightning NOx emissions inventory for use by the U.S. Environmental Protection Agency (EPA) Community Multiscale Air Quality (CMAQ) modeling system. Overall, special attention is given to several important lightning variables including: the frequency and geographical distribution of lightning in the vicinity of the NALMA network, lightning type (ground or cloud flash), lightning channel length, channel altitude, channel peak current, and the number of strokes per flash. Laboratory spark chamber results from the literature are used to convert 1-meter channel segments (that are located at a particular known altitude; i.e., air density) to NOx concentration. The resulting lightning NOx source profiles are discussed.

  8. Electromagnetic sensors for general lightning application

    NASA Technical Reports Server (NTRS)

    Baum, C. E.; Breen, E. L.; Onell, J. P.; Moore, C. B.; Sower, G. D.

    1980-01-01

    Electromagnetic sensors for general lightning applications in measuring environment are discussed as well as system response to the environment. This includes electric and magnetic fields, surface current and charge densities, and currents on conductors. Many EMP sensors are directly applicable to lightning measurements, but there are some special cases of lightning measurements involving direct strikes which require special design considerations for the sensors. The sensors and instrumentation used by NMIMT in collecting data on lightning at South Baldy peak in central New Mexico during the 1978 and 1979 lightning seasons are also discussed. The Langmuir Laboratory facilities and details of the underground shielded instrumentation room and recording equipment are presented.

  9. Estimates of the Lightning NOx Profile in the Vicinity of the North Alabama Lightning Mapping Array

    NASA Technical Reports Server (NTRS)

    Koshak, William J.; Peterson, Harold

    2010-01-01

    The NASA Marshall Space Flight Center Lightning Nitrogen Oxides Model (LNOM) is applied to August 2006 North Alabama Lightning Mapping Array (LMA) data to estimate the raw (i.e., unmixed and otherwise environmentally unmodified) vertical profile of lightning nitrogen oxides, NOx = NO + NO 2 . This is part of a larger effort aimed at building a more realistic lightning NOx emissions inventory for use by the U.S. Environmental Protection Agency (EPA) Community Multiscale Air Quality (CMAQ) modeling system. Data from the National Lightning Detection Network TM (NLDN) is also employed. Overall, special attention is given to several important lightning variables including: the frequency and geographical distribution of lightning in the vicinity of the LMA network, lightning type (ground or cloud flash), lightning channel length, channel altitude, channel peak current, and the number of strokes per flash. Laboratory spark chamber results from the literature are used to convert 1-meter channel segments (that are located at a particular known altitude; i.e., air density) to NOx concentration. The resulting raw NOx profiles are discussed.

  10. Isolation of Lightning-Competent Soil Bacteria

    PubMed Central

    Cérémonie, Hélène; Buret, François; Simonet, Pascal; Vogel, Timothy M.

    2004-01-01

    Artificial transformation is typically performed in the laboratory by using either a chemical (CaCl2) or an electrical (electroporation) method. However, laboratory-scale lightning has been shown recently to electrotransform Escherichia coli strain DH10B in soil. In this paper, we report on the isolation of two “lightning-competent” soil bacteria after direct electroporation of the Nycodenz bacterial ring extracted from prairie soil in the presence of the pBHCRec plasmid (Tcr, Spr, Smr). The electrotransformability of the isolated bacteria was measured both in vitro (by electroporation cuvette) and in situ (by lightning in soil microcosm) and then compared to those of E. coli DH10B and Pseudomonas fluorescens C7R12. The electrotransformation frequencies measured reached 10−3 to 10−4 by electroporation and 10−4 to 10−5 by simulated lightning, while no transformation was observed in the absence of electrical current. Two of the isolated lightning-competent soil bacteria were identified as Pseudomonas sp. strains. PMID:15466589

  11. Implementing a Remote Laboratory Experience into a Joint Engineering Degree Program: Aerodynamic Levitation of a Beach Ball

    ERIC Educational Resources Information Center

    Jernigan, S. R.; Fahmy, Y.; Buckner, G. D.

    2009-01-01

    This paper details a successful and inexpensive implementation of a remote laboratory into a distance control systems course using readily available hardware and software. The physical experiment consists of a beach ball and a dc blower; the control objective is to make the height of the aerodynamically levitated beach ball track a reference…

  12. Simultaneous emissions of X-rays and microwaves from long laboratory sparks and downward lightning leaders

    NASA Astrophysics Data System (ADS)

    Montanya, J.; Oscar, V. D. V.; Tapia, F. F.

    2017-12-01

    Since the discovery of the Terrestrial Gamma-ray Flashes more than 20 years ago, investigations on high energy emissions from natural lightning and high voltage laboratory sparks gained significant interest. X-ray emissions from lightning as well from high voltage laboratory sparks have in common the role played by negative leaders/streamers. On the other hand, negative leaders are well known to produce much more VHF and microwave radiation than positive leaders. Moreover, in previous works, microwave emissions from lightning leaders have been attributed to Bremsstrahlung process. The object of this work is to investigate if X-rays and RF microwave emissions share the same origin. We present simultaneous measurements of X-rays and microwaves in high voltage sparks and natural lightning. The instrumentation consists on a NaI(Tl) and LaBr3 scintillation detectors and two different receivers. One is fix tuned at 2.4 GHz with a bandwidth of 5.5 MHz. The second can be tuned at any frequency up to 18 GHz with different selectable bandwidths of 10 MHz, 40 MHz and 100 MHz. In the laboratory, results have shown that all the sparks presented microwave radiation before the breakdown of the gap, either X-rays were detected or not. In the cases where X-rays were identified, microwave emissions peaked at the same time (in the microsecond scale). We found that the power amplitudes of the microwave emissions are related to the applied voltage to the gap. In the same configuration, those cases where X-rays were detected microwave emissions presented higher power levels. The results suggest that in some part of the discharge electrons are very fast accelerated allowing, in some cases, to reach enought energy to produce X-rays. In the field, we have found similar results. On 13th of June of 2015 a bipolar cloud-to-ground flash struck 200 m close to the Eagle Nest instrumented tower (Spanish Pyrenees, 2536 m ASL). The flash presented four strokes and, in all of them, microwave

  13. Laboratory modeling and analysis of aircraft-lightning interactions

    NASA Technical Reports Server (NTRS)

    Turner, C. D.; Trost, T. F.

    1982-01-01

    Modeling studies of the interaction of a delta wing aircraft with direct lightning strikes were carried out using an approximate scale model of an F-106B. The model, which is three feet in length, is subjected to direct injection of fast current pulses supplied by wires, which simulate the lightning channel and are attached at various locations on the model. Measurements are made of the resulting transient electromagnetic fields using time derivative sensors. The sensor outputs are sampled and digitized by computer. The noise level is reduced by averaging the sensor output from ten input pulses at each sample time. Computer analysis of the measured fields includes Fourier transformation and the computation of transfer functions for the model. Prony analysis is also used to determine the natural frequencies of the model. Comparisons of model natural frequencies extracted by Prony analysis with those for in flight direct strike data usually show lower damping in the in flight case. This is indicative of either a lightning channel with a higher impedance than the wires on the model, only one attachment point, or short streamers instead of a long channel.

  14. Central hyperadrenergic state after lightning strike.

    PubMed

    Parsaik, Ajay K; Ahlskog, J Eric; Singer, Wolfgang; Gelfman, Russell; Sheldon, Seth H; Seime, Richard J; Craft, Jennifer M; Staab, Jeffrey P; Kantor, Birgit; Low, Phillip A

    2013-08-01

    To describe and review autonomic complications of lightning strike. Case report and laboratory data including autonomic function tests in a subject who was struck by lightning. A 24-year-old man was struck by lightning. Following that, he developed dysautonomia, with persistent inappropriate sinus tachycardia and autonomic storms, as well as posttraumatic stress disorder (PTSD) and functional neurologic problems. The combination of persistent sinus tachycardia and episodic exacerbations associated with hypertension, diaphoresis, and agitation was highly suggestive of a central hyperadrenergic state with superimposed autonomic storms. Whether the additional PTSD and functional neurologic deficits were due to a direct effect of the lightning strike on the central nervous system or a secondary response is open to speculation.

  15. Summary report of the Lightning and Static Electricity Committee

    NASA Technical Reports Server (NTRS)

    Plumer, J. A.

    1979-01-01

    Lightning protection technology as applied to aviation and identifying these technology needs are presented. The flight areas of technical needs include; (1) the need for In-Flight data on lightning electrical parameters; (2) technology base and guidelines for protection of advanced systems and structures; (3) improved laboratory test techniques; (4) analysis techniques for predicting induced effects; (5) lightning strike incident data from General Aviation; (6) lightning detection systems; (7) obtain pilot reports of lightning strikes; and (8) better training in lightning awareness. The nature of each problem, timeliness, impact of solutions, degree of effort required, and the roles of government and industry in achieving solutions are discussed.

  16. Central Hyperadrenergic State After Lightning Strike

    PubMed Central

    Parsaik, Ajay K.; Ahlskog, J. Eric; Singer, Wolfgang; Gelfman, Russell; Sheldon, Seth H.; Seime, Richard J.; Craft, Jennifer M.; Staab, Jeffrey P.; Kantor, Birgit; Low, Phillip A.

    2013-01-01

    Objective To describe and review autonomic complications of lightning strike. Methods Case report and laboratory data including autonomic function tests in a subject who was struck by lightning. Results A 24-year-old man was struck by lightning. Following that, he developed dysautonomia, with persistent inappropriate sinus tachycardia and autonomic storms, as well as posttraumatic stress disorder (PTSD) and functional neurologic problems. Interpretation The combination of persistent sinus tachycardia and episodic exacerbations associated with hypertension, diaphoresis, and agitation were highly suggestive of a central hyperadrenergic state with superimposed autonomic storms. Whether the additional PTSD and functional neurologic deficits were due to a direct effect of the lightning strike on the CNS or a secondary response is open to speculation. PMID:23761114

  17. The Elusive Evidence of Volcanic Lightning.

    PubMed

    Genareau, K; Gharghabi, P; Gafford, J; Mazzola, M

    2017-11-14

    Lightning strikes are known to morphologically alter and chemically reduce geologic formations and deposits, forming fulgurites. A similar process occurs as the result of volcanic lightning discharge, when airborne volcanic ash is transformed into lightning-induced volcanic spherules (LIVS). Here, we adapt the calculations used in previous studies of lightning-induced damage to infrastructure materials to determine the effects on pseudo-ash samples of simplified composition. Using laboratory high-current impulse experiments, this research shows that within the lightning discharge channel there is an ideal melting zone that represents roughly 10% or less of the total channel radius at which temperatures are sufficient to melt the ash, regardless of peak current. The melted ash is simultaneously expelled from the channel by the heated, expanding air, permitting particles to cool during atmospheric transport before coming to rest in ash fall deposits. The limited size of this ideal melting zone explains the low number of LIVS typically observed in volcanic ash despite the frequent occurrence of lightning during explosive eruptions.

  18. Evaluation of the damages caused by lightning current flowing through bearings

    NASA Technical Reports Server (NTRS)

    Celi, O.; Pigini, A.; Garbagnati, E.

    1991-01-01

    A laboratory for lightning current tests was set up allowing the generation of the lightning currents foreseen by the Standards. Lightning tests are carried out on different objects, aircraft materials and components, evaluating the direct and indirect effects of lightning. Recently a research was carried out to evaluate the effects of the lightning current flow through bearings with special reference to wind power generator applications. For this purpose, lightning currents of different amplitude were applied to bearings in different test conditions and the damages caused by the lightning current flow were analyzed. The influence of the load acting on the bearing, the presence of lubricant and the bearing rotation were studied.

  19. Lightning attachment process to common buildings

    NASA Astrophysics Data System (ADS)

    Saba, M. M. F.; Paiva, A. R.; Schumann, C.; Ferro, M. A. S.; Naccarato, K. P.; Silva, J. C. O.; Siqueira, F. V. C.; Custódio, D. M.

    2017-05-01

    The physical mechanism of lightning attachment to grounded structures is one of the most important issues in lightning physics research, and it is the basis for the design of the lightning protection systems. Most of what is known about the attachment process comes from leader propagation models that are mostly based on laboratory observations of long electrical discharges or from observations of lightning attachment to tall structures. In this paper we use high-speed videos to analyze the attachment process of downward lightning flashes to an ordinary residential building. For the first time, we present characteristics of the attachment process to common structures that are present in almost every city (in this case, two buildings under 60 m in São Paulo City, Brazil). Parameters like striking distance and connecting leaders speed, largely used in lightning attachment models and in lightning protection standards, are revealed in this work.Plain Language SummarySince the time of Benjamin Franklin, no one has ever recorded high-speed video images of a <span class="hlt">lightning</span> connection to a common building. It is very difficult to do it. Cameras need to be very close to the structure chosen to be observed, and long observation time is required to register one <span class="hlt">lightning</span> strike to that particular structure. Models and theories used to determine the zone of protection of a <span class="hlt">lightning</span> rod have been developed, but they all suffer from the lack of field data. The submitted manuscript provides results from high-speed video observations of <span class="hlt">lightning</span> attachment to low buildings that are commonly found in almost every populated area around the world. The proximity of the camera and the high frame rate allowed us to see interesting details that will improve the understanding of the attachment process and, consequently, the models and theories used by <span class="hlt">lightning</span> protection standards. This paper also presents spectacular images and videos of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMAE33A0265S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMAE33A0265S"><span><span class="hlt">Lightning</span> Magnetic Field Measurements around Langmuir <span class="hlt">Laboratory</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stock, M.; Krehbiel, P. R.; Rison, W.; Aulich, G. D.; Edens, H. E.; Sonnenfeld, R. G.</p> <p>2010-12-01</p> <p>In the absence of artificial conductors, underground <span class="hlt">lightning</span> transients are produced by diffusion of the horizontal surface magnetic field of a return stroke vertically downward into the conducting earth. The changing magnetic flux produces an orthogonal horizontal electric field, generating a dispersive, lossy transverse electromagnetic wave that penetrates a hundred meters or more into the ground according to the skin depth of the medium. In turn, the electric field produces currents that flow toward or away from the channel to ground depending on the stroke polarity. The underground transients can produce large radial horizontal potential gradients depending on the distance from the discharge and depth below the surface. In this study we focus on the surface excitation field. The goal of the work is to compare measurements of surface magnetic field waveforms B(t) at different distances from natural <span class="hlt">lightning</span> discharges with simple and detailed models of the return stroke fields. In addition to providing input to the diffusion mechanism, the results should aid in further understanding return stroke field generation processes. The observational data are to be obtained using orthogonal sets of straightened Rogowski coils to measure magnetic field waveforms in N-S and E-W directions. The waveforms are sampled at 500 kS/s over 1.024 second time intervals and recorded directly onto secure digital cards. The instrument operates off of battery power for several days or weeks at a time in remote, unattended locations and measures magnetic field strengths of up to several tens of amperes/meter. The observations are being made in conjunction with collocated slow electric field change measurements and under good 3-D <span class="hlt">lightning</span> mapping array (LMA) and fast electric field change coverage.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_3 --> <div id="page_4" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="61"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JGRD..116.9103A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JGRD..116.9103A"><span>Acoustic localization of triggered <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arechiga, Rene O.; Johnson, Jeffrey B.; Edens, Harald E.; Thomas, Ronald J.; Rison, William</p> <p>2011-05-01</p> <p>We use acoustic (3.3-500 Hz) arrays to locate local (<20 km) thunder produced by triggered <span class="hlt">lightning</span> in the Magdalena Mountains of central New Mexico. The locations of the thunder sources are determined by the array back azimuth and the elapsed time since discharge of the <span class="hlt">lightning</span> flash. We compare the acoustic source locations with those obtained by the <span class="hlt">Lightning</span> Mapping Array (LMA) from Langmuir <span class="hlt">Laboratory</span>, which is capable of accurately locating the <span class="hlt">lightning</span> channels. To estimate the location accuracy of the acoustic array we performed Monte Carlo simulations and measured the distance (nearest neighbors) between acoustic and LMA sources. For close sources (<5 km) the mean nearest-neighbors distance was 185 m compared to 100 m predicted by the Monte Carlo analysis. For far distances (>6 km) the error increases to 800 m for the nearest neighbors and 650 m for the Monte Carlo analysis. This work shows that thunder sources can be accurately located using acoustic signals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMAE33A0266A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMAE33A0266A"><span>Acoustic Manifestations of Natural versus Triggered <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arechiga, R. O.; Johnson, J. B.; Edens, H. E.; Rison, W.; Thomas, R. J.; Eack, K.; Eastvedt, E. M.; Aulich, G. D.; Trueblood, J.</p> <p>2010-12-01</p> <p>Positive leaders are rarely detected by VHF <span class="hlt">lightning</span> detection systems; positive leader channels are usually outlined only by recoil events. Positive cloud-to-ground (CG) channels are usually not mapped. The goal of this work is to study the types of thunder produced by natural versus triggered <span class="hlt">lightning</span> and to assess which types of thunder signals have electromagnetic activity detected by the <span class="hlt">lightning</span> mapping array (LMA). Towards this end we are investigating the <span class="hlt">lightning</span> detection capabilities of acoustic techniques, and comparing them with the LMA. In a previous study we used array beam forming and time of flight information to locate acoustic sources associated with <span class="hlt">lightning</span>. Even though there was some mismatch, generally LMA and acoustic techniques saw the same phenomena. To increase the database of acoustic data from <span class="hlt">lightning</span>, we deployed a network of three infrasound arrays (30 m aperture) during the summer of 2010 (August 3 to present) in the Magdalena mountains of New Mexico, to monitor infrasound (below 20 Hz) and audio range sources due to natural and triggered <span class="hlt">lightning</span>. The arrays were located at a range of distances (60 to 1400 m) surrounding the triggering site, called the Kiva, used by Langmuir <span class="hlt">Laboratory</span> to launch rockets. We have continuous acoustic measurements of <span class="hlt">lightning</span> data from July 20 to September 18 of 2009, and from August 3 to September 1 of 2010. So far, <span class="hlt">lightning</span> activity around the Kiva was higher during the summer of 2009. We will present acoustic data from several interesting <span class="hlt">lightning</span> flashes including a comparison between a natural and a triggered one.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRD..123.2861H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRD..123.2861H"><span>LOFAR <span class="hlt">Lightning</span> Imaging: Mapping <span class="hlt">Lightning</span> With Nanosecond Precision</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hare, B. M.; Scholten, O.; Bonardi, A.; Buitink, S.; Corstanje, A.; Ebert, U.; Falcke, H.; Hörandel, J. R.; Leijnse, H.; Mitra, P.; Mulrey, K.; Nelles, A.; Rachen, J. P.; Rossetto, L.; Rutjes, C.; Schellart, P.; Thoudam, S.; Trinh, T. N. G.; ter Veen, S.; Winchen, T.</p> <p>2018-03-01</p> <p><span class="hlt">Lightning</span> mapping technology has proven instrumental in understanding <span class="hlt">lightning</span>. In this work we present a pipeline that can use <span class="hlt">lightning</span> observed by the LOw-Frequency ARray (LOFAR) radio telescope to construct a 3-D map of the flash. We show that LOFAR has unparalleled precision, on the order of meters, even for <span class="hlt">lightning</span> flashes that are over 20 km outside the area enclosed by LOFAR antennas (˜3,200 km2), and can potentially locate over 10,000 sources per <span class="hlt">lightning</span> flash. We also show that LOFAR is the first <span class="hlt">lightning</span> mapping system that is sensitive to the spatial structure of the electrical current during individual <span class="hlt">lightning</span> leader steps.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023330','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023330"><span>Simulation and measurement of melting effects on metal sheets caused by direct <span class="hlt">lightning</span> strikes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kern, Alexander</p> <p>1991-01-01</p> <p>Direct <span class="hlt">lightning</span> strikes melt metal parts of various systems, like fuel and propellant tanks of rockets and airplanes, at the point of strike. Responsible for this melting are the impulse current and, if occurring, the long duration current, both carrying a remarkable charge Q. For studying these meltings the simulation in the <span class="hlt">laboratory</span> has to be based on the parameters of natural <span class="hlt">lightnings</span>. International standards exist defining certain threat levels of natural <span class="hlt">lightnings</span> and giving possible generator circuits for the simulation. The melting caused by both types of <span class="hlt">lightning</span> currents show different appearance. Their characteristics, their differences in melting and heating of metal sheets are investigated. Nevertheless the simulation of <span class="hlt">lightning</span> in the <span class="hlt">laboratory</span> is imperfect. While natural <span class="hlt">lightning</span> is a discharge without a counter electrode, the simulation always demands a close counter electrode. The influence of this counter electrode is studied.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhPl...13k3503T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhPl...13k3503T"><span>Self-similar magnetohydrodynamic model for direct current discharge fireball experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tsui, K. H.; Navia, C. E.; Robba, M. B.; Carneiro, L. T.; Emelin, S. E.</p> <p>2006-11-01</p> <p><span class="hlt">Ball</span> <span class="hlt">lightning</span> models and corresponding <span class="hlt">laboratory</span> efforts in generating fireballs are briefly summarized to give an overview of the current status. In particular, emphasis is given to direct current discharge experiments at atmospheric pressure such as capillary discharge with a plasma plume in front of the anode opening [Emelin et al., Tech. Phys. Letters 23, 758 (1997)] and water resistor discharge with fluttering fireball overhead [Egorov and Stepanov, Tech. Phys. 47, 1584 (2002)]. These fireballs are interpreted as <span class="hlt">laboratory</span> demonstrations of the self-similar magnetohydrodynamic (MHD) model of <span class="hlt">ball</span> <span class="hlt">lightning</span> [Tsui, Phys. Plasmas 13, 072102 (2006)].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.V43E3189M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.V43E3189M"><span>Volcanic <span class="hlt">Lightning</span> in the <span class="hlt">Laboratory</span>: The Effect of Ultra-Rapid Melting on Ash Particles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mueller, S.; Keller, F.; Helo, C.; Buhre, S.; Castro, J. M.</p> <p>2016-12-01</p> <p><span class="hlt">Lightning</span> discharge is a common process occurring at explosive volcanic eruptions. During the formation of ash plumes, the dynamical interaction of ash particles creates charges which can, given a sufficiently large charge gradient, cause <span class="hlt">lightning</span> discharges within the plume (`plume <span class="hlt">lightning</span>') or from ground to plume (`near-vent <span class="hlt">lightning</span>'), respectively. Given the extreme heat release during the short duration of a discharge (potentially > 30.000 K), it is likely that the ash particles suspended in a plume are, in any form, affected by volcanic <span class="hlt">lightning</span>. Genareau et al. (2015) found evidence of glass spherules and glass aggregates in ash deposits of two explosive eruptions (Eyjafjallajökull, Mt. Redoubt), and linked them to short-term melting processes induced by volcanic <span class="hlt">lightning</span> (analogue to fulgurites). In order to systematically investigate the potential impact of <span class="hlt">lightning</span> on air-suspended ash we have designed a new experimental setup. An electric arc between two electrodes is generated by a 400 Amp arc welding device. Ash-sized sample material is then blown into the established <span class="hlt">lightning</span> arc, and a certain proportion of the injected silicate glasses and/or minerals is melted due to the high temperatures in and around the plasma channel. In a first set of experiments, we have used natural volcanic ash from Laacher See Tephra (Eifel, Germany) in distinct size fractions between 36 and 250 microns, in order to qualitatively investigate melting and amalgamation features. Spherule and aggregate textures similar to those reported by Genareau et al. (2015) were successfully reproduced during these experiments. In a second set of experiments, homogenized phonolitic glass fragments, in different size fractions, were subjected to the electric arc and subsequently analyzed under the EMP, in order to investigate effects of "flash melting" on major element glass chemistry. Genareau K, Wardman JB, Wilson TM, McNutt SR, Izbekov P (2015): <span class="hlt">Lightning</span>-induced volcanic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SASS...32..123K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SASS...32..123K"><span>21st Century <span class="hlt">Lightning</span> Protection for High Altitude Observatories</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kithil, Richard</p> <p>2013-05-01</p> <p>One of the first recorded <span class="hlt">lightning</span> insults to an observatory was in January 1890 at the Ben Nevis Observatory in Scotland. In more recent times <span class="hlt">lightning</span> has caused equipment losses and data destruction at the US Air Force Maui Space Surveillance Complex, the Cerro Tololo observatory and the nearby La Serena scientific and technical office, the VLLA, and the Apache Point Observatory. In August 1997 NOAA's Climate Monitoring and Diagnostic <span class="hlt">Laboratory</span> at Mauna Loa Observatory was out of commission for a month due to <span class="hlt">lightning</span> outages to data acquisition computers and connected cabling. The University of Arizona has reported "<span class="hlt">lightning</span> strikes have taken a heavy toll at all Steward Observatory sites." At Kitt Peak, extensive power down protocols are in place where <span class="hlt">lightning</span> protection for personnel, electrical systems, associated electronics and data are critical. Designstage <span class="hlt">lightning</span> protection defenses are to be incorporated at NSO's ATST Hawaii facility. For high altitude observatories <span class="hlt">lightning</span> protection no longer is as simple as Franklin's 1752 invention of a rod in the air, one in the ground and a connecting conductor. This paper discusses selection of engineered <span class="hlt">lightning</span> protection subsystems in a carefully planned methodology which is specific to each site.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1334109','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1334109"><span>2016 T Division <span class="hlt">Lightning</span> Talks</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Ramsey, Marilyn Leann; Adams, Luke Clyde; Ferre, Gregoire Robing</p> <p></p> <p>These are the slides for all of the 2016 T Division <span class="hlt">lightning</span> talks. There are 350 pages worth of slides from different presentations, all of which cover different topics within the theoretical division at Los Alamos National <span class="hlt">Laboratory</span> (LANL).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFMAE24A..01J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFMAE24A..01J"><span>An Overview of LANL's New Hurricane <span class="hlt">Lightning</span> Project (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jeffery, C. A.; Shao, X.; Reisner, J.; Kao, C. J.; Brockwell, M.; Chylek, P.; Fierro, A.; Galassi, M.; Godinez, H. C.; Guimond, S.; Hamlin, T.; Henderson, B. G.; Ho, C.; Holden, D.; Light, T. E.; O'Connor, N.; Suszcynsky, D. M.</p> <p>2009-12-01</p> <p>For the last two years, Los Alamos National <span class="hlt">Laboratory</span> has sponsored an internal hurricane <span class="hlt">lightning</span> project with four main goals: (1) To develop and deploy a new dual VLF/VHF <span class="hlt">lightning</span> mapping array in the Mississippi River Delta south of New Orleans. (2) To develop a new hurricane forecast capability with fully prognostic cloud electrification and <span class="hlt">lightning</span> discharge physics, based on a model framework developed at Oklahoma University. (3) To develop a new data assimilation approach for ingesting LANL <span class="hlt">lightning</span> data into our forecast model that exploits the phenomenological relationship between <span class="hlt">lightning</span> occurrence and intense convection. (4) To demonstrate that the assimilation of <span class="hlt">lightning</span> data from the new LANL Gulf array into the hurricane forecast model improves the prediction of rapid intensification (RI), when RI is driven by eyewall adjustment (axisymmetrization) triggered by intense convective events (hot towers). In this talk, I present an overview of LANL's new hurricane lighting project, and the progress we have made to-date in achieving the project's four main goals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26873252','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26873252"><span>[Neurological diseases after <span class="hlt">lightning</span> strike : <span class="hlt">Lightning</span> strikes twice].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gruhn, K M; Knossalla, Frauke; Schwenkreis, Peter; Hamsen, Uwe; Schildhauer, Thomas A; Tegenthoff, Martin; Sczesny-Kaiser, Matthias</p> <p>2016-06-01</p> <p><span class="hlt">Lightning</span> strikes rarely occur but 85 % of patients have <span class="hlt">lightning</span>-related neurological complications. This report provides an overview about different modes of energy transfer and neurological conditions related to <span class="hlt">lightning</span> strikes. Moreover, two case reports demonstrate the importance of interdisciplinary treatment and the spectrum of neurological complications after <span class="hlt">lightning</span> strikes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810060330&hterms=thunder+lightning&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dthunder%2Blightning','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810060330&hterms=thunder+lightning&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dthunder%2Blightning"><span>Measurement of RF <span class="hlt">lightning</span> emissions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lott, G. K., Jr.; Honnell, M. A.; Shumpert, T. H.</p> <p>1981-01-01</p> <p>A <span class="hlt">lightning</span> radio emission observation <span class="hlt">laboratory</span> is described. The signals observed and recorded include HF, VHF and UHF radio emissions, optical signature, electric field measurements, and thunder. The objectives of the station, the equipment used, and the recording methods are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840040382&hterms=barret&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dbarret','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840040382&hterms=barret&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dbarret"><span>Correlated observations of three triggered <span class="hlt">lightning</span> flashes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Idone, V. P.; Orville, R. E.; Hubert, P.; Barret, L.; Eybert-Berard, A.</p> <p>1984-01-01</p> <p>Three triggered <span class="hlt">lightning</span> flashes, initiated during the Thunderstorm Research International Program (1981) at Langmuir <span class="hlt">Laboratory</span>, New Mexico, are examined on the basis of three-dimensional return stroke propagation speeds and peak currents. Nonlinear relationships result between return stroke propagation speed and stroke peak current for 56 strokes, and between return stroke propagation speed and dart leader propagation speed for 32 strokes. Calculated linear correlation coefficients include dart leader propagation speed and ensuing return stroke peak current (32 strokes; r = 0.84); and stroke peak current and interstroke interval (69 strokes; r = 0.57). Earlier natural <span class="hlt">lightning</span> data do not concur with the weak positive correlation between dart leader propagation speed and interstroke interval. Therefore, application of triggered <span class="hlt">lightning</span> results to natural <span class="hlt">lightning</span> phenomena must be made with certain caveats. Mean values are included for the three-dimensional return stroke propagation speed and for the three-dimensional dart leader propagation speed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001JChEd..78.1519H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001JChEd..78.1519H"><span>Synthesis and Self-Assembly of the "Tennis <span class="hlt">Ball</span>" Dimer and Subsequent Encapsulation of Methane. An Advanced Organic Chemistry <span class="hlt">Laboratory</span> Experiment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hof, Fraser; Palmer, Liam C.; Rebek, Julius, Jr.</p> <p>2001-11-01</p> <p>While important to the biological and materials sciences, noncovalent interactions, self-folding, and self-assembly often receive little discussion in the undergraduate chemistry curriculum. The synthesis and NMR characterization of a molecular "tennis <span class="hlt">ball</span>" in an advanced undergraduate organic chemistry <span class="hlt">laboratory</span> is a simple and effective way to introduce the relevance of these concepts. In appropriate solvents, the monomer dimerizes through a seam of eight hydrogen bonds with encapsulation of a guest molecule and symmetry reminiscent of a tennis <span class="hlt">ball</span>. The entire experiment can be completed in three lab periods, however large-scale synthetic preparation of the starting monomer by a teaching assistant would reduce the <span class="hlt">laboratory</span> to a single lab period for NMR studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170010354','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170010354"><span><span class="hlt">Lightning</span> NOx Estimates from Space-Based <span class="hlt">Lightning</span> Imagers</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William J.</p> <p>2017-01-01</p> <p>The intense heating of air by a <span class="hlt">lightning</span> channel, and subsequent rapid cooling, leads to the production of <span class="hlt">lightning</span> nitrogen oxides (NOx = NO + NO2) as discussed in Chameides [1979]. In turn, the <span class="hlt">lightning</span> nitrogen oxides (or "LNOx" for brevity) indirectly influences the Earth's climate because the LNOx molecules are important in controlling the concentration of ozone (O3) and hydroxyl radicals (OH) in the atmosphere. Climate is most sensitive to O3 in the upper troposphere, and LNOx is the most important source of NOx in the upper troposphere at tropical and subtropical latitudes; hence, <span class="hlt">lightning</span> is a useful parameter to monitor for climate assessments. The National Climate Assessment (NCA) program was created in response to the Congressionally-mandated Global Change Research Act (GCRA) of 1990. Thirteen US government organizations participate in the NCA program which examines the effects of global change on the natural environment, human health and welfare, energy production and use, land and water resources, human social systems, transportation, agriculture, and biological diversity. The NCA focuses on natural and human-induced trends in global change, and projects major trends 25 to 100 years out. In support of the NCA, the NASA Marshall Space Flight Center (MSFC) continues to assess <span class="hlt">lightning</span>-climate inter-relationships. This activity applies a variety of NASA assets to monitor in detail the changes in both the characteristics of ground- and space- based <span class="hlt">lightning</span> observations as they pertain to changes in climate. In particular, changes in <span class="hlt">lightning</span> characteristics over the conterminous US (CONUS) continue to be examined by this author using data from the Tropical Rainfall Measuring Mission <span class="hlt">Lightning</span> Imaging Sensor. In this study, preliminary estimates of LNOx trends derived from TRMM/LIS <span class="hlt">lightning</span> optical energy observations in the 17 yr period 1998-2014 are provided. This represents an important first step in testing the ability to make remote retrievals</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012GeoRL..3919807E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012GeoRL..3919807E"><span>VHF <span class="hlt">lightning</span> mapping observations of a triggered <span class="hlt">lightning</span> flash</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Edens, H. E.; Eack, K. B.; Eastvedt, E. M.; Trueblood, J. J.; Winn, W. P.; Krehbiel, P. R.; Aulich, G. D.; Hunyady, S. J.; Murray, W. C.; Rison, W.; Behnke, S. A.; Thomas, R. J.</p> <p>2012-10-01</p> <p>On 3 August 2010 an extensive <span class="hlt">lightning</span> flash was triggered over Langmuir <span class="hlt">Laboratory</span> in New Mexico. The upward positive leader propagated into the storm's midlevel negative charge region, extending over a horizontal area of 13 × 13 km and 7.5 km altitude. The storm had a normal-polarity tripolar charge structure with upper positive charge over midlevel negative charge. <span class="hlt">Lightning</span> Mapping Array (LMA) observations were used to estimate positive leader velocities along various branches, which were in the range of 1-3 × 104 m s-1, slower than in other studies. The upward positive leader initiated at 3.4 km altitude, but was mapped only above 4.0 km altitude after the onset of retrograde negative breakdown, indicating a change in leader propagation and VHF emissions. The observations suggest that both positive and negative breakdown produce VHF emissions that can be located by time-of-arrival systems, and that not all VHF emissions occurring along positive leader channels are associated with retrograde negative breakdown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150002884','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150002884"><span>An Integrated 0-1 Hour First-Flash <span class="hlt">Lightning</span> Nowcasting, <span class="hlt">Lightning</span> Amount and <span class="hlt">Lightning</span> Jump Warning Capability</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mecikalski, John; Jewett, Chris; Carey, Larry; Zavodsky, Brad; Stano, Geoffrey</p> <p>2015-01-01</p> <p><span class="hlt">Lightning</span> one of the most dangerous weather-related phenomena, especially as many jobs and activities occur outdoors, presenting risk from a <span class="hlt">lightning</span> strike. Cloud-to-ground (CG) <span class="hlt">lightning</span> represents a considerable safety threat to people at airfields, marinas, and outdoor facilities-from airfield personnel, to people attending outdoor stadium events, on beaches and golf courses, to mariners, as well as emergency personnel. Holle et al. (2005) show that 90% of <span class="hlt">lightning</span> deaths occurred outdoors, while 10% occurred indoors despite the perception of safety when inside buildings. Curran et al. (2000) found that nearly half of fatalities due to weather were related to convective weather in the 1992-1994 timeframe, with <span class="hlt">lightning</span> causing a large component of the fatalities, in addition to tornadoes and flash flooding. Related to the aviation industry, CG <span class="hlt">lightning</span> represents a considerable hazard to baggage-handlers, aircraft refuelers, food caterers, and emergency personnel, who all become exposed to the risk of being struck within short time periods while convective storm clouds develop. Airport safety protocols require that ramp operations be modified or discontinued when <span class="hlt">lightning</span> is in the vicinity (typically 16 km), which becomes very costly and disruptive to flight operations. Therefore, much focus has been paid to nowcasting the first-time initiation and extent of <span class="hlt">lightning</span>, both of CG and of any <span class="hlt">lightning</span> (e.g, in-cloud, cloud-to-cloud). For this project three <span class="hlt">lightning</span> nowcasting methodologies will be combined: (1) a GOESbased 0-1 hour <span class="hlt">lightning</span> initiation (LI) product (Harris et al. 2010; Iskenderian et al. 2012), (2) a High Resolution Rapid Refresh (HRRR) <span class="hlt">lightning</span> probability and forecasted <span class="hlt">lightning</span> flash density product, such that a quantitative amount of <span class="hlt">lightning</span> (QL) can be assigned to a location of expected LI, and (3) an algorithm that relates Pseudo-GLM data (Stano et al. 2012, 2014) to the so-called "<span class="hlt">lightning</span> jump" (LJ) methodology (Shultz et al</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26471123','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26471123"><span>The start of <span class="hlt">lightning</span>: Evidence of bidirectional <span class="hlt">lightning</span> initiation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Montanyà, Joan; van der Velde, Oscar; Williams, Earle R</p> <p>2015-10-16</p> <p><span class="hlt">Lightning</span> flashes are known to initiate in regions of strong electric fields inside thunderstorms, between layers of positively and negatively charged precipitation particles. For that reason, <span class="hlt">lightning</span> inception is typically hidden from sight of camera systems used in research. Other technology such as <span class="hlt">lightning</span> mapping systems based on radio waves can typically detect only some aspects of the <span class="hlt">lightning</span> initiation process and subsequent development of positive and negative leaders. We report here a serendipitous recording of bidirectional <span class="hlt">lightning</span> initiation in virgin air under the cloud base at ~11,000 images per second, and the differences in characteristics of opposite polarity leader sections during the earliest stages of the discharge. This case reveals natural <span class="hlt">lightning</span> initiation, propagation and a return stroke as in negative cloud-to-ground flashes, upon connection to another <span class="hlt">lightning</span> channel - without any masking by cloud.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/20717491-effect-corona-discharge-lightning-attachment','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/20717491-effect-corona-discharge-lightning-attachment"><span>The Effect of a Corona Discharge on a <span class="hlt">Lightning</span> Attachment</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Aleksandrov, N.L.; Bazelyan, E.M.; Raizer, Yu.P.</p> <p>2005-01-15</p> <p>The interaction between the <span class="hlt">lightning</span> leader and the space charge accumulated near the top of a ground object in the atmospheric electric field is considered using analytical and numerical models developed earlier to describe spark discharges in long <span class="hlt">laboratory</span> gaps. The specific features of a nonstationary corona discharge that develops in the electric field of a thundercloud and a downward <span class="hlt">lightning</span> leader are analyzed. Conditions for the development of an upward <span class="hlt">lightning</span> discharge from a ground object and for the propagation of an upward-connecting leader from the object toward a downward <span class="hlt">lightning</span> leader (the process determining the point of strikemore » to the ground) are investigated. Possible mechanisms for the interaction of the corona space charge with an upward leader and prospects of using it to control downward <span class="hlt">lightning</span> discharges are analyzed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040047196&hterms=GLOBAL+WARNING&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DGLOBAL%2BWARNING','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040047196&hterms=GLOBAL+WARNING&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DGLOBAL%2BWARNING"><span>Global <span class="hlt">Lightning</span> Activity</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Christian, Hugh J.</p> <p>2004-01-01</p> <p>Our knowledge of the global distribution of <span class="hlt">lightning</span> has improved dramatically since the advent of spacebased <span class="hlt">lightning</span> observations. Of major importance was the 1995 launch of the Optical Transient Detector (OTD), followed in 1997 by the launch of the <span class="hlt">Lightning</span> Imaging Sensor (LIS). Together, these instruments have generated a continuous eight-year record of global <span class="hlt">lightning</span> activity. These <span class="hlt">lightning</span> observations have provided a new global perspective on total <span class="hlt">lightning</span> activity. For the first time, total <span class="hlt">lightning</span> activity (cloud-to-ground and intra-cloud) has been observed over large regions with high detection efficiency and accurate geographic location. This has produced new insights into <span class="hlt">lightning</span> distributions, times of occurrence and variability. It has produced a revised global flash rate estimate (44 flashes per second) and has lead to a new realization of the significance of total <span class="hlt">lightning</span> activity in severe weather. Accurate flash rate estimates are now available over large areas of the earth (+/- 72 deg. latitude). Ocean-land contrasts as a function of season are clearly reveled, as are orographic effects and seasonal and interannual variability. The space-based observations indicate that air mass thunderstorms, not large storm system dominate global activity. The ability of LIS and OTD to detect total <span class="hlt">lightning</span> has lead to improved insight into the correlation between <span class="hlt">lightning</span> and storm development. The relationship between updraft development and <span class="hlt">lightning</span> activity is now well established and presents an opportunity for providing a new mechanism for remotely monitoring storm development. In this concept, <span class="hlt">lightning</span> would serve as a surrogate for updraft velocity. It is anticipated that this capability could lead to significantly improved severe weather warning times and reduced false warning rates. This talk will summarize our space-based <span class="hlt">lightning</span> measurements, will discuss how <span class="hlt">lightning</span> observations can be used to monitor severe weather, and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20090017890&hterms=epa&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Depa','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20090017890&hterms=epa&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Depa"><span>A NASA <span class="hlt">Lightning</span> Parameterization for CMAQ</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William; Khan, Maudood; Biazar, Arastoo; Newchurch, Mike; McNider, Richard</p> <p>2009-01-01</p> <p>Many state and local air quality agencies use the U.S. Environmental Protection Agency (EPA) Community Multiscale Air Quality (CMAQ) modeling system to determine compliance with the National Ambient Air Quality Standards (NAAQS). Because emission reduction scenarios are tested using CMAQ with an aim of determining the most efficient and cost effective strategies for attaining the NAAQS, it is very important that trace gas concentrations derived by CMAQ are accurate. Overestimating concentrations can literally translate into billions of dollars lost by commercial and government industries forced to comply with the standards. Costly health, environmental and socioeconomic problems can result from concentration underestimates. Unfortunately, <span class="hlt">lightning</span> modeling for CMAQ is highly oversimplified. This leads to very poor estimates of <span class="hlt">lightning</span>-produced nitrogen oxides "NOx" (= NO + NO2) which directly reduces the accuracy of the concentrations of important CMAQ trace gases linked to NOx concentrations such as ozone and methane. Today it is known that <span class="hlt">lightning</span> is the most important NOx source in the upper troposphere with a global production rate estimated to vary between 2-20 Tg(N)/yr. In addition, NOx indirectly influences our climate since it controls the concentration of ozone and hydroxyl radicals (OH) in the atmosphere. Ozone is an important greenhouse gas and OH controls the oxidation of various greenhouse gases. We describe a robust NASA <span class="hlt">lightning</span> model, called the <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) that combines state-of-the-art <span class="hlt">lightning</span> measurements, empirical results from field studies, and beneficial <span class="hlt">laboratory</span> results to arrive at a realistic representation of <span class="hlt">lightning</span> NOx production for CMAQ. NASA satellite <span class="hlt">lightning</span> data is used in conjunction with ground-based <span class="hlt">lightning</span> detection systems to assure that the best representation of <span class="hlt">lightning</span> frequency, geographic location, channel length, channel altitude, strength (i.e., channel peak current), and</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120003988','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120003988"><span>Using Total <span class="hlt">Lightning</span> Observations to Enhance <span class="hlt">Lightning</span> Safety</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stano, Geoffrey T.</p> <p>2012-01-01</p> <p><span class="hlt">Lightning</span> is often the underrated threat faced by the public when it comes to dangerous weather phenomena. Typically, larger scale events such as floods, hurricanes, and tornadoes receive the vast majority of attention by both the general population and the media. This comes from the fact that these phenomena are large, longer lasting, can impact a large swath of society at one time, and are dangerous events. The threat of <span class="hlt">lightning</span> is far more isolated on a case by case basis, although millions of cloud-to-ground <span class="hlt">lightning</span> strikes hit this United States each year. While attention is given to larger meteorological events, <span class="hlt">lightning</span> is the second leading cause of weather related deaths in the United States. This information raises the question of what steps can be taken to improve <span class="hlt">lightning</span> safety. Already, the meteorological community s understanding of <span class="hlt">lightning</span> has increased over the last 20 years. <span class="hlt">Lightning</span> safety is now better addressed with the National Weather Service s access to the National <span class="hlt">Lightning</span> Detection Network data and enhanced wording in their severe weather warnings. Also, local groups and organizations are working to improve public awareness of <span class="hlt">lightning</span> safety with easy phrases to remember, such as "When Thunder Roars, Go Indoors." The impacts can be seen in the greater array of contingency plans, from airports to sports stadiums, addressing the threat of <span class="hlt">lightning</span>. Improvements can still be made and newer technologies may offer new tools as we look towards the future. One of these tools is a network of sensors called a <span class="hlt">lightning</span> mapping array (LMA). Several of these networks exist across the United States. NASA s Short-term Prediction Research and Transition Center (SPoRT), part of the Marshall Spaceflight Center, has access to three of these networks from Huntsville, Alabama, the Kennedy Space Center, and Washington D.C. The SPoRT program s mission is to help transition unique products and observations into the operational forecast environment</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/978220-regulatory-guidance-lightning-protection-nuclear-power-plants','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/978220-regulatory-guidance-lightning-protection-nuclear-power-plants"><span>Regulatory Guidance for <span class="hlt">Lightning</span> Protection in Nuclear Power Plants</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Kisner, Roger A; Wilgen, John B; Ewing, Paul D</p> <p>2006-01-01</p> <p>Abstract - Oak Ridge National <span class="hlt">Laboratory</span> (ORNL) was engaged by the U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research (RES) to develop the technical basis for regulatory guidance to address design and implementation practices for <span class="hlt">lightning</span> protection systems in nuclear power plants (NPPs). <span class="hlt">Lightning</span> protection is becoming increasingly important with the advent of digital and low-voltage analog systems in NPPs. These systems have the potential to be more vulnerable than older analog systems to the resulting power surges and electromagnetic interference (EMI) when <span class="hlt">lightning</span> strikes facilities or power lines. This paper discusses the technical basis for guidance tomore » licensees and applicants covered in Regulatory Guide (RG) 1.204, Guidelines for <span class="hlt">Lightning</span> Protection of Nuclear Power Plants, issued August 2005. RG 1.204 describes guidance for practices that are acceptable to the NRC staff for protecting nuclear power structures and systems from direct <span class="hlt">lightning</span> strikes and the resulting secondary effects.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22030075-regulatory-guidance-lightning-protection-nuclear-power-plants','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22030075-regulatory-guidance-lightning-protection-nuclear-power-plants"><span>Regulatory guidance for <span class="hlt">lightning</span> protection in nuclear power plants</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Kisner, R. A.; Wilgen, J. B.; Ewing, P. D.</p> <p>2006-07-01</p> <p>Oak Ridge National <span class="hlt">Laboratory</span> (ORNL) was engaged by the U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research (RES) to develop the technical basis for regulatory guidance to address design and implementation practices for <span class="hlt">lightning</span> protection systems in nuclear power plants (NPPs). <span class="hlt">Lightning</span> protection is becoming increasingly important with the advent of digital and low-voltage analog systems in NPPs. These systems have the potential to be more vulnerable than older analog systems to the resulting power surges and electromagnetic interference (EMI) when <span class="hlt">lightning</span> strikes facilities or power lines. This paper discusses the technical basis for guidance to licensees andmore » applicants covered in Regulatory Guide (RG) 1.204, Guidelines for <span class="hlt">Lightning</span> Protection of Nuclear Power Plants, issued August 2005. RG 1.204 describes guidance for practices that are acceptable to the NRC staff for protecting nuclear power structures and systems from direct <span class="hlt">lightning</span> strikes and the resulting secondary effects. (authors)« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993AREPS..21...43R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993AREPS..21...43R"><span>Planetary <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Russell, C. T.; Clayton, R. N.; Buseck, P. R.; Hua, X.; Holsapple, K. A.; Esposito, L. W.; Aherns, T. J.; Hecht, J.</p> <p></p> <p>The present state of knowledge concerning <span class="hlt">lightning</span> on the planets is reviewed. Voyager data have clearly established the presence of <span class="hlt">lightning</span> discharges at each of the four Jovian planets. In situ data for <span class="hlt">lightning</span> on Venus are discussed in some detail, including reported quantitative occurrence rates and hypotheses concerning the relationship of Venusian <span class="hlt">lightning</span> to VLF bursts observed in the Venus atmosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMAE31A0424D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMAE31A0424D"><span>Oceanic <span class="hlt">Lightning</span> versus Continental <span class="hlt">Lightning</span>: VLF Peak Current Discrepancies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dupree, N. A., Jr.; Moore, R. C.</p> <p>2015-12-01</p> <p>Recent analysis of the Vaisala global <span class="hlt">lightning</span> data set GLD360 suggests that oceanic <span class="hlt">lightning</span> tends to exhibit larger peak currents than continental <span class="hlt">lightning</span> (<span class="hlt">lightning</span> occurring over land). The GLD360 peak current measurement is derived from distant measurements of the electromagnetic fields emanated during the <span class="hlt">lightning</span> flash. Because the GLD360 peak current measurement is a derived quantity, it is not clear whether the actual peak currents of oceanic <span class="hlt">lightning</span> tend to be larger, or whether the resulting electromagnetic field strengths tend to be larger. In this paper, we present simulations of VLF signal propagation in the Earth-ionosphere waveguide to demonstrate that the peak field values for oceanic <span class="hlt">lightning</span> can be significantly stronger than for continental <span class="hlt">lightning</span>. Modeling simulations are performed using the Long Wave Propagation Capability (LWPC) code to directly evaluate the effect of ground conductivity on VLF signal propagation in the 5-15 kHz band. LWPC is an inherently narrowband propagation code that has been modified to predict the broadband response of the Earth-Ionosphere waveguide to an impulsive <span class="hlt">lightning</span> flash while preserving the ability of LWPC to account for an inhomogeneous waveguide. Furthermore, we evaluate the effect of return stroke speed on these results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900007374','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900007374"><span>Rocket-triggered <span class="hlt">lightning</span> strikes and forest fire ignition</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fenner, James H.</p> <p>1989-01-01</p> <p>Background information on the rocket-triggered <span class="hlt">lightning</span> project at Kennedy Space Center (KSC), a summary of the forecasting problem there, the facilities and equipment available for undertaking field experiments at KSC, previous research activity performed, a description of the atmospheric science field <span class="hlt">laboratory</span> near Mosquito Lagoon on the KSC complex, methods of data acquisition, and present results are discussed. New sources of data for the 1989 field experiment include measuring the electric field in the lower few thousand feet of the atmosphere by suspending field measuring devices below a tethered balloon. Problems encountered during the 1989 field experiment are discussed. Future prospects for both triggered <span class="hlt">lightning</span> and <span class="hlt">lightning</span>-kindled forest fire research at KSC are listed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E1643R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E1643R"><span><span class="hlt">Lightning</span> and Life on Exoplanets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rimmer, Paul; Ardaseva, Aleksandra; Hodosan, Gabriella; Helling, Christiane</p> <p>2016-07-01</p> <p>Miller and Urey performed a ground-breaking experiment, in which they discovered that electric discharges through a low redox ratio gas of methane, ammonia, water vapor and hydrogen produced a variety of amino acids, the building blocks of proteins. Since this experiment, there has been significant interest on the connection between <span class="hlt">lightning</span> chemistry and the origin of life. Investigation into the atmosphere of the Early Earth has generated a serious challenge for this project, as it has been determined both that Earth's early atmosphere was likely dominated by carbon dioxide and molecular nitrogen with only small amounts of hydrogen, having a very high redox ratio, and that discharges in gases with high redox ratios fail to yield more than trace amounts of biologically relevant products. This challenge has motivated several origin of life researchers to abandon <span class="hlt">lightning</span> chemistry, and to concentrate on other pathways for prebiotic synthesis. The discovery of over 2000 exoplanets includes a handful of rocky planets within the habitable zones around their host stars. These planets can be viewed as remote <span class="hlt">laboratories</span> in which efficient <span class="hlt">lightning</span> driven prebiotic synthesis may take place. This is because many of these rocky exoplanets, called super-Earths, have masses significantly greater than that of Earth. This higher mass would allow them to more retain greater amounts hydrogen within their atmosphere, reducing the redox ratio. Discharges in super-Earth atmospheres can therefore result in a significant yield of amino acids. In this talk, I will discuss new work on what <span class="hlt">lightning</span> might look like on exoplanets, and on <span class="hlt">lightning</span> driven chemistry on super-Earths. Using a chemical kinetics model for a super-Earth atmosphere with smaller redox ratios, I will show that in the presence of <span class="hlt">lightning</span>, the production of the amino acid glycine is enhanced up to a certain point, but with very low redox ratios, the production of glycine is again inhibited. I will conclude</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMAE33A0339B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMAE33A0339B"><span>Characteristics of VLF/LF Sferics from Elve-producing <span class="hlt">Lightning</span> Discharges</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blaes, P.; Zoghzoghy, F. G.; Marshall, R. A.</p> <p>2013-12-01</p> <p><span class="hlt">Lightning</span> return strokes radiate an electromagnetic pulse (EMP) which interacts with the D-region ionosphere; the largest EMPs produce new ionization, heating, and optical emissions known as elves. Elves are at least six times more common than sprites and other transient luminous events. Though the probability that a <span class="hlt">lightning</span> return stroke will produce an elve is correlated with the return stroke peak current, many large peak current strokes do not produce visible elves. Apart from the <span class="hlt">lightning</span> peak current, elve production may depend on the return stroke speed, <span class="hlt">lightning</span> altitude, and ionospheric conditions. In this work we investigate the detailed structure of <span class="hlt">lightning</span> that gives rise to elves by analyzing the characteristics of VLF/LF <span class="hlt">lightning</span> sferics in conjunction with optical elve observations. <span class="hlt">Lightning</span> sferics were observed using an array of six VLF/LF receivers (1 MHz sample-rate) in Oklahoma, and elves were observed using two high-speed photometers pointed over the Oklahoma region: one located at Langmuir <span class="hlt">Laboratory</span>, NM and the other at McDonald Observatory, TX. Hundreds of elves with coincident LF sferics were observed during the summer months of 2013. We present data comparing the characteristics of elve-producing and non-elve producing <span class="hlt">lightning</span> as measured by LF sferics. In addition, we compare these sferic and elve observations with FDTD simulations to determine key properties of elve-producing <span class="hlt">lightning</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMAE13A0417M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMAE13A0417M"><span><span class="hlt">Lightning</span> spectra at 100,000 fps</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McHarg, M. G.; Harley, J.; Haaland, R. K.; Edens, H. E.; Stenbaek-Nielsen, H.</p> <p>2016-12-01</p> <p>A fundamental understanding of <span class="hlt">lightning</span> can be inferred from the spectral emissions resulting from the leader and return stroke channel. We examine an event recorded at 00:58:07 on 19 July 2015 at Langmuir <span class="hlt">Laboratory</span>. We recorded <span class="hlt">lightning</span> spectra using a 100 line per mm grating in front of a Phantom V2010 camera with an 85mm Nikon lens recording at 100,000 frames per second. Coarse resolution spectra (approximately 5nm resolution) are produced from approximately 400 nm to 800 nm for each frame. Electric field data from the Langmuir Electric Field Array for the 03:19:19 event show 10 V/m changes in the electric field associated with multiple return strokes visible in the spectral data. We used the spectral data to compare temperatures at the top, middle and bottom of the <span class="hlt">lightning</span> channel. <span class="hlt">Lightning</span> Mapping Array data at Langmuir for the 00:58:07 event show a complex flash extending 10 km in the East-West plane and 6 km in the North-South plane. The imagery data imply that this is a bolt-from-the-blue event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016plp..book.....M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016plp..book.....M"><span>Principles of <span class="hlt">Lightning</span> Physics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mazur, Vladislav</p> <p>2016-12-01</p> <p>Principles of <span class="hlt">Lightning</span> Physics presents and discusses the most up-to-date physical concepts that govern many <span class="hlt">lightning</span> events in nature, including <span class="hlt">lightning</span> interactions with man-made structures, at a level suitable for researchers, advanced students and well-educated <span class="hlt">lightning</span> enthusiasts. The author's approach to understanding <span class="hlt">lightning</span>-to seek out, and show what is common to all <span class="hlt">lightning</span> flashes-is illustrated by an analysis of each type of <span class="hlt">lightning</span> and the multitude of <span class="hlt">lightning</span>-related features. The book examines the work that has gone into the development of new physical concepts, and provides critical evaluations of the existing understanding of the physics of <span class="hlt">lightning</span> and the lexicon of terms and definitions presently used in <span class="hlt">lightning</span> research.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120001523','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120001523"><span>A Summary of the NASA <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) and Recent Results</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William; Peterson, Harld</p> <p>2011-01-01</p> <p>The NASA Marshall Space Flight Center introduced the <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) a couple of years ago to combine routine state-of-the-art measurements of <span class="hlt">lightning</span> with empirical <span class="hlt">laboratory</span> results of <span class="hlt">lightning</span> NOx production. The routine measurements included VHF <span class="hlt">lightning</span> source data [such as from the North Alabama <span class="hlt">Lightning</span> Mapping Array (LMA)], and ground flash location, peak current, and stroke multiplicity data from the National <span class="hlt">Lightning</span> Detection Network(TradeMark) (NLDN). Following these initial runs of LNOM, the model was updated to include several non-return stroke <span class="hlt">lightning</span> NOx production mechanisms, and provided the impact of <span class="hlt">lightning</span> NOx on an August 2006 run of CMAQ. In this study, we review the evolution of the LNOM in greater detail and discuss the model?s latest upgrades and applications. Whereas previous applications were limited to five summer months of data for North Alabama thunderstorms, the most recent LNOM analyses cover several years. The latest statistics of ground and cloud flash NOx production are provided.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20030062188&hterms=GLOBAL+WARNING&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DGLOBAL%2BWARNING','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20030062188&hterms=GLOBAL+WARNING&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DGLOBAL%2BWARNING"><span>Global <span class="hlt">Lightning</span> Activity</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Christian, Hugh</p> <p>2003-01-01</p> <p>Our knowledge of the global distribution of <span class="hlt">lightning</span> has improved dramatically since the 1995 launch of the Optical Transient Detector (OTD) followed in 1997 by the launch of the <span class="hlt">Lightning</span> Imaging Sensor (LIS). Together, these instruments have generated a continuous seven-year record of global <span class="hlt">lightning</span> activity. These <span class="hlt">lightning</span> observations have provided a new global perspective on total <span class="hlt">lightning</span> activity. For the first time, total <span class="hlt">lightning</span> activity (CG and IC) has been observed over large regions with high detection efficiencies and accurate geographic location. This has produced new insights into <span class="hlt">lightning</span> distributions, times of occurrence and variability. It has produced a revised global flash rate estimate (46 flashes per second) and has lead to a new realization of the significance of total <span class="hlt">lightning</span> activity in severe weather. Accurate flash rate estimates are now available for large areas of the earth (+/- 72deg latitude) Ocean-land contrasts as a function of season are clearly revealed, as are orographic effects and seasonal and interannual variability. The data set indicates that air mass thunderstorms, not large storm systems dominate global activity. The ability of LIS and OTD to detect total <span class="hlt">lightning</span> has lead to improved insight into the correlation between <span class="hlt">lightning</span> and storm development. The relationship between updraft development and <span class="hlt">lightning</span> activity is now well established and presents an opportunity for providing a new mechanism for remotely monitoring storm development. In this concept, <span class="hlt">lightning</span> would serve as a surrogate for updraft velocity. It is anticipated hat this capability could lead to significantly improved severe weather warning times and reduced false warning rates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMAE31A..01W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMAE31A..01W"><span><span class="hlt">Lightning</span> and Climate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Williams, E.</p> <p>2012-12-01</p> <p><span class="hlt">Lightning</span> is of interest in the domain of climate change for several reasons: (1) thunderstorms are extreme forms of moist convection, and <span class="hlt">lightning</span> flash rate is a sensitive measure of that extremity, (2) thunderstorms are deep conduits for delivering water substance from the boundary layer to the upper troposphere and stratosphere, and (3) global <span class="hlt">lightning</span> can be monitored continuously and inexpensively within a natural framework (the Earth-ionosphere waveguide and Schumann resonances). <span class="hlt">Lightning</span> and temperature, and <span class="hlt">lightning</span> and upper tropospheric water vapor, are positively correlated on weather-related time scales (diurnal, semiannual, and annual) with a <span class="hlt">lightning</span> temperature sensitivity of order 10% per oC. <span class="hlt">Lightning</span> also follows temperature variations on the ENSO time scale, both locally and globally. The response of <span class="hlt">lightning</span> in some of its extreme forms (exceptional flash rates and the prevalence of sprite-producing mesoscale <span class="hlt">lightning</span>, for example) to temperature variations will be addressed. Consistently obtained records of <span class="hlt">lightning</span> activity on longer time scales are scarce as stable detection networks are uncommon. As a consequence, thunder day data have been used to extend the <span class="hlt">lightning</span> record for climate studies, with evidence for increases over decades in urban areas. Global records of <span class="hlt">lightning</span> following Schumann resonance intensity and from space-based optical sensors (OTD and LIS) are consistent with the record of ionospheric potential representing the global electrical circuit in showing flat behavior over the few decades. This flatness is not well understood, though the majority of all <span class="hlt">lightning</span> flashes are found in the tropics, the most closely regulated portion of the atmosphere. Other analysis of frequency variations of Schumann resonances in recent decades shows increased <span class="hlt">lightning</span> in the northern hemisphere, where the global warming is most pronounced. The quantity more fundamental than temperature for <span class="hlt">lightning</span> control is cloud buoyancy</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMAE33B2552D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE33B2552D"><span><span class="hlt">Lightning</span> leader models of terrestrial gamma-ray flashes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dwyer, J. R.; Liu, N.; Ihaddadene, K. M. A.</p> <p>2017-12-01</p> <p>Terrestrial gamma-ray flashes (TGFs) are bright sub-millisecond bursts of gamma rays that originate from thunderstorms. Because <span class="hlt">lightning</span> leaders near the ground have been observed to emit x-rays, presumably due to runaway electron production in the high-field regions near the leader tips, models of TGFs have been developed by several groups that assume a similar production mechanism of runaway electrons from <span class="hlt">lightning</span> leaders propagating through thunderclouds. However, it remains unclear exactly how and where these runaway electrons are produced, since <span class="hlt">lightning</span> propagation at thunderstorm altitudes remains poorly understood. In addition, it is not obvious how to connect the observed behavior of the x-ray production from <span class="hlt">lightning</span> near the ground with the properties of TGFs. For example, it is not clear how to relate the time structure of the x-ray emission near the ground to that of TGFs, since x-rays from stepped leaders near the ground are usually produced in a series of sub-microsecond bursts, but TGFs are usually observed as much longer pulses without clear substructures, at sub-microsecond timescales or otherwise. In this presentation, spacecraft observations of TGFs, ground-based observations of x-rays from <span class="hlt">lightning</span> and <span class="hlt">laboratory</span> sparks, and Monte Carlo and PIC simulations of runaway electron and gamma ray production and propagation will be used to constrain the <span class="hlt">lightning</span> leader models of TGFs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhDT.......302K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhDT.......302K"><span><span class="hlt">Lightning</span> Strike Induced Damage Mechanisms of Carbon Fiber Composites</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kawakami, Hirohide</p> <p></p> <p>Composite materials have a wide application in aerospace, automotive, and other transportation industries, because of the superior structural and weight performances. Since carbon fiber reinforced polymer composites possess a much lower electrical conductivity as compared to traditional metallic materials utilized for aircraft structures, serious concern about damage resistance/tolerance against <span class="hlt">lightning</span> has been rising. Main task of this study is to clarify the <span class="hlt">lightning</span> damage mechanism of carbon fiber reinforced epoxy polymer composites to help further development of <span class="hlt">lightning</span> strike protection. The research on <span class="hlt">lightning</span> damage to carbon fiber reinforced polymer composites is quite challenging, and there has been little study available until now. In order to tackle this issue, building block approach was employed. The research was started with the development of supporting technologies such as a current impulse generator to simulate a <span class="hlt">lightning</span> strike in a <span class="hlt">laboratory</span>. Then, fundamental electrical properties and fracture behavior of CFRPs exposed to high and low level current impulse were investigated using simple coupon specimens, followed by extensive parametric investigations in terms of different prepreg materials frequently used in aerospace industry, various stacking sequences, different <span class="hlt">lightning</span> intensity, and <span class="hlt">lightning</span> current waveforms. It revealed that the thermal resistance capability of polymer matrix was one of the most influential parameters on <span class="hlt">lightning</span> damage resistance of CFRPs. Based on the experimental findings, the semi-empirical analysis model for predicting the extent of <span class="hlt">lightning</span> damage was established. The model was fitted through experimental data to determine empirical parameters and, then, showed a good capability to provide reliable predictions for other test conditions and materials. Finally, structural element level <span class="hlt">lightning</span> tests were performed to explore more practical situations. Specifically, filled-hole CFRP plates and patch</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRD..123.2347S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRD..123.2347S"><span>Characteristics of <span class="hlt">Lightning</span> Within Electrified Snowfall Events Using <span class="hlt">Lightning</span> Mapping Arrays</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schultz, Christopher J.; Lang, Timothy J.; Bruning, Eric C.; Calhoun, Kristin M.; Harkema, Sebastian; Curtis, Nathan</p> <p>2018-02-01</p> <p>This study examined 34 <span class="hlt">lightning</span> flashes within four separate thundersnow events derived from <span class="hlt">lightning</span> mapping arrays (LMAs) in northern Alabama, central Oklahoma, and Washington DC. The goals were to characterize the in-cloud component of each <span class="hlt">lightning</span> flash, as well as the correspondence between the LMA observations and <span class="hlt">lightning</span> data taken from national <span class="hlt">lightning</span> networks like the National <span class="hlt">Lightning</span> Detection Network (NLDN). Individual flashes were examined in detail to highlight several observations within the data set. The study results demonstrated that the structures of these flashes were primarily normal polarity. The mean area encompassed by this set of flashes is 375 km2, with a maximum flash extent of 2,300 km2, a minimum of 3 km2, and a median of 128 km2. An average of 2.29 NLDN flashes were recorded per LMA-derived <span class="hlt">lightning</span> flash. A maximum of 11 NLDN flashes were recorded in association with a single LMA-derived flash on 10 January 2011. Additionally, seven of the 34 flashes in the study contain zero NLDN-identified flashes. Eleven of the 34 flashes initiated from tall human-made objects (e.g., communication towers). In at least six <span class="hlt">lightning</span> flashes, the NLDN detected a return stroke from the cloud back to the tower and not the initial upward leader. This study also discusses <span class="hlt">lightning</span>'s interaction with the human-built environment and provides an example of <span class="hlt">lightning</span> within heavy snowfall observed by Geostationary Operational Environmental Satellite-16's Geostationary <span class="hlt">Lightning</span> Mapper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29910996','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29910996"><span>Characteristics of <span class="hlt">Lightning</span> within Electrified Snowfall Events using <span class="hlt">Lightning</span> Mapping Arrays.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schultz, Christopher J; Lang, Timothy J; Bruning, Eric C; Calhoun, Kristin M; Harkema, Sebastian; Curtis, Nathan</p> <p>2018-02-27</p> <p>This study examined 34 <span class="hlt">lightning</span> flashes within four separate thundersnow events derived from <span class="hlt">lightning</span> mapping arrays (LMAs) in northern Alabama, central Oklahoma, and Washington DC. The goals were to characterize the in-cloud component of each <span class="hlt">lightning</span> flash, as well as the correspondence between the LMA observations and <span class="hlt">lightning</span> data taken from national <span class="hlt">lightning</span> networks like the National <span class="hlt">Lightning</span> Detection Network (NLDN). Individual flashes were examined in detail to highlight several observations within the dataset. The study results demonstrated that the structures of these flashes were primarily normal polarity. The mean area encompassed by this set of flashes is 375 km 2 , with a maximum flash extent of 2300 km 2 , a minimum of 3 km 2 , and a median of 128 km 2 . An average of 2.29 NLDN flashes were recorded per LMA-derived <span class="hlt">lightning</span> flash. A maximum of 11 NLDN flashes were recorded in association with a single LMA-derived flash on 10 January 2011. Additionally, seven of the 34 flashes in the study contain zero NLDN identified flashes. Eleven of the 34 flashes initiated from tall human-made objects (e.g., communication towers). In at least six <span class="hlt">lightning</span> flashes, the NLDN detected a return stroke from the cloud back to the tower and not the initial upward leader. This study also discusses <span class="hlt">lightning</span>'s interaction with the human built environment and provides an example of <span class="hlt">lightning</span> within heavy snowfall observed by GOES-16's Geostationary <span class="hlt">Lightning</span> Mapper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMAE12A..06B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMAE12A..06B"><span>Trends in <span class="hlt">Lightning</span> Electrical Energy Derived from the <span class="hlt">Lightning</span> Imaging Sensor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bitzer, P. M.; Koshak, W. J.</p> <p>2016-12-01</p> <p>We present results detailing an emerging application of space-based measurement of <span class="hlt">lightning</span>: the electrical energy. This is a little-used attribute of <span class="hlt">lightning</span> data which can have applications for severe weather, <span class="hlt">lightning</span> physics, and wildfires. In particular, we use data from the Tropical Rainfall Measuring Mission <span class="hlt">Lightning</span> Imaging Sensor (TRMM/LIS) to find the temporal and spatial variations in the detected spectral energy density. This is used to estimate the total <span class="hlt">lightning</span> electrical energy, following established methodologies. Results showing the trend in time of the electrical energy, as well as the distribution around the globe, will be highlighted. While flashes have been typically used in most studies, the basic scientifically-relevant measured unit by LIS is the optical group data product. This generally corresponds to a return stroke or IC pulse. We explore how the electrical energy varies per LIS group, providing an extension and comparison with previous investigations. The result is an initial climatology of this new and important application of space-based optical measurements of <span class="hlt">lightning</span>, which can provide a baseline for future applications using the Geostationary <span class="hlt">Lightning</span> Mapper (GLM), the European <span class="hlt">Lightning</span> Imager (LI), and the International Space Station <span class="hlt">Lightning</span> Imaging Sensor (ISS/LIS) instruments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/8848654','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/8848654"><span><span class="hlt">Lightning</span> and transportation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cherington, M</p> <p>1995-12-01</p> <p>It is a little-known fact that <span class="hlt">lightning</span> casualties often involve travel or transportation. López and colleagues, in their studies on the epidemiology of <span class="hlt">lightning</span> injuries, have reported that 10% of <span class="hlt">lightning</span> injuries are categorized under transportation. In the majority of their cases, victims were struck while standing outside or near their vehicles during a thunderstorm. During my review of the neurologic complications of <span class="hlt">lightning</span> injuries, I was impressed by the number of case reports in which the victim was struck while either in or near a vehicle, airplane or vessel. In this article, I shall put forth information on four aspects of <span class="hlt">lightning</span> that relate to the danger to people traveling in vehicles, boats, and airplanes. First, I shall deal with <span class="hlt">lightning</span> safety on ships and boats. People who enjoy recreational sailing, including the "weekend sailor" and those who enjoy fishing from a boat, should be fortified with knowledge about <span class="hlt">lightning</span> protection. Second, I shall consider the matter of <span class="hlt">lightning</span> strikes to aircraft. In the third section, I shall discuss the question of <span class="hlt">lightning</span> safety in automobiles. Fourth, I shall review those cases found in my literature review in which the victim was struck while in or near a vehicle, boat, or airplane.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840024295','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840024295"><span><span class="hlt">Lightning</span> swept-stroke attachment patterns and flight conditions for storm hazards 1981</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fisher, B. D.</p> <p>1984-01-01</p> <p>As part of the NASA Langley Research Center Storm Hazards Program, 111 thunderstorm penetrations were made in 1981 with an F-106B airplane in order to record direct-strike <span class="hlt">lightning</span> data and the associated flight conditions. Ground-based weather radar measurements in conjunction with these penetrations were made by NOAA National Severe Storms <span class="hlt">Laboratory</span> in Oklahoma and by NASA Wallops Flight Facility in Virginia. In 1981, the airplane received 10 direct <span class="hlt">lightning</span> strikes; in addition, <span class="hlt">lightning</span> transient data were recorded from 22 nearby flashes. Following each flight, the airplane was thoroughly inspected for evidence of <span class="hlt">lightning</span> attachment, and the individual <span class="hlt">lightning</span> attachment points were plotted on isometric projections of the airplane to identify swept-flash patterns. This report shows the strike attachment patterns that were found, and tabulates the flight conditions at the time of each <span class="hlt">lightning</span> event. Finally, this paper contains a table in which the data in this report are cross-referenced with the previously published electromagnetic waveform data recorded onboard the airplane.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUSMAE53A..01B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUSMAE53A..01B"><span><span class="hlt">Lightning</span> Location Using Acoustic Signals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Badillo, E.; Arechiga, R. O.; Thomas, R. J.</p> <p>2013-05-01</p> <p>In the summer of 2011 and 2012 a network of acoustic arrays was deployed in the Magdalena mountains of central New Mexico to locate <span class="hlt">lightning</span> flashes. A Times-Correlation (TC) ray-tracing-based-technique was developed in order to obtain the location of <span class="hlt">lightning</span> flashes near the network. The TC technique, locates acoustic sources from <span class="hlt">lightning</span>. It was developed to complement the <span class="hlt">lightning</span> location of RF sources detected by the <span class="hlt">Lightning</span> Mapping Array (LMA) developed at Langmuir <span class="hlt">Laboratory</span>, in New Mexico Tech. The network consisted of four arrays with four microphones each. The microphones on each array were placed in a triangular configuration with one of the microphones in the center of the array. The distance between the central microphone and the rest of them was about 30 m. The distance between centers of the arrays ranged from 500 m to 1500 m. The TC technique uses times of arrival (TOA) of acoustic waves to trace back the location of thunder sources. In order to obtain the times of arrival, the signals were filtered in a frequency band of 2 to 20 hertz and cross-correlated. Once the times of arrival were obtained, the Levenberg-Marquardt algorithm was applied to locate the spatial coordinates (x,y, and z) of thunder sources. Two techniques were used and contrasted to compute the accuracy of the TC method: Nearest-Neighbors (NN), between acoustic and LMA located sources, and standard deviation from the curvature matrix of the system as a measure of dispersion of the results. For the best case scenario, a triggered <span class="hlt">lightning</span> event, the TC method applied with four microphones, located sources with a median error of 152 m and 142.9 m using nearest-neighbors and standard deviation respectively.; Results of the TC method in the <span class="hlt">lightning</span> event recorded at 18:47:35 UTC, August 6, 2012. Black dots represent the results computed. Light color dots represent the LMA data for the same event. The results were obtained with the MGTM station (four channels). This figure</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830005806','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830005806"><span><span class="hlt">Lightning</span> attachment patterns and flight conditions for storm hazards, 1980</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fisher, B. D.; Keyser, G. L., Jr.; Deal, P. L.</p> <p>1982-01-01</p> <p>As part of the NASA Langley Research Center Storm Hazards Program, 69 thunderstorm pentrations were made in 1980 with an F-106B airplane in order to record direct strike <span class="hlt">lightning</span> data and the associated flight conditions. Ground based weather radar measurements in conjunction with these penetrations were made by NOAA National Severe Storms <span class="hlt">Laboratory</span> in Oklahoma and by NASA Wallops Flight Center in Virginia. In 1980, the airplane received 10 direct <span class="hlt">lightning</span> strikes; in addition, <span class="hlt">lightning</span> transient data were recorded from 6 nearby flashes. Following each flight, the airplane was thoroughly inspected for evidence of <span class="hlt">lightning</span> attachment, and the individual <span class="hlt">lightning</span> attachment points were plotted on isometric projections of the airplane to identify swept flash patterns. This report presents pilot descriptions of the direct strikes to the airplane, shows the strike attachment patterns that were found, and discusses the implications of the patterns with respect to aircraft protection design. The flight conditions are also included. Finally, the <span class="hlt">lightning</span> strike scenarios for three U.S. Air Force F-106A airplanes which were struck during routine operations are given in the appendix to this paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150002889','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150002889"><span>Total <span class="hlt">Lightning</span> Characteristics with Respect to Radar-Derived Mesocyclone Strength</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stough, Sarah M.; Carey, Lawrence D.; Schultz, Christopher J.</p> <p>2015-01-01</p> <p>Recent work investigating the microphysical and kinematic relationship between a storm's updraft, its total <span class="hlt">lightning</span> production, and manifestations of severe weather has resulted in development of tools for improved nowcasting of storm intensity. The total <span class="hlt">lightning</span> jump algorithm, which identifies rapid increases in total <span class="hlt">lightning</span> flash rate that often precede severe events, has shown particular potential to benefit warning operations. Maximizing this capability of total <span class="hlt">lightning</span> and its operational implementation via the <span class="hlt">lightning</span> jump may best be done through its fusion with radar and radar-derived intensity metrics. Identification of a mesocyclone, or quasi-steady rotating updraft, in Doppler velocity is the predominant radar-inferred early indicator of severe potential in a convective storm. Fused <span class="hlt">lightning</span>-radar tools that capitalize on the most robust intensity indicators would allow enhanced situational awareness for increased warning confidence. A foundational step toward such tools comes from a better understanding of the updraft-centric relationship between intensification of total <span class="hlt">lightning</span> production and mesocyclone development and strength. The work presented here utilizes a sample of supercell case studies representing a spectrum of severity. These storms are analyzed with respect to total <span class="hlt">lightning</span> flash rate and the <span class="hlt">lightning</span> jump alongside mesocyclone strength derived objectively from the National Severe Storms <span class="hlt">Laboratory</span> (NSSL) Mesocyclone Detection Algorithm (MDA) and maximum azimuthal shear through a layer. Early results indicate that temporal similarities exist in the trends between total <span class="hlt">lightning</span> flash rate and low- to mid-level rotation in supercells. Other characteristics such as polarimetric signatures of rotation, flash size, and cloud-to-ground flash ratio are explored for added insight into the significance of these trends with respect to the updraft and related processes of severe weather production.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23389051','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23389051"><span>Process engineering with planetary <span class="hlt">ball</span> mills.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Burmeister, Christine Friederike; Kwade, Arno</p> <p>2013-09-21</p> <p>Planetary <span class="hlt">ball</span> mills are well known and used for particle size reduction on <span class="hlt">laboratory</span> and pilot scales for decades while during the last few years the application of planetary <span class="hlt">ball</span> mills has extended to mechanochemical approaches. Processes inside planetary <span class="hlt">ball</span> mills are complex and strongly depend on the processed material and synthesis and, thus, the optimum milling conditions have to be assessed for each individual system. The present review focuses on the insight into several parameters like properties of grinding <span class="hlt">balls</span>, the filling ratio or revolution speed. It gives examples of the aspects of grinding and illustrates some general guidelines to follow for modelling processes in planetary <span class="hlt">ball</span> mills in terms of refinement, synthesis' yield and contamination from wear. The amount of energy transferred from the milling tools to the powder is significant and hardly measurable for processes in planetary <span class="hlt">ball</span> mills. Thus numerical simulations based on a discrete-element-method are used to describe the energy transfer to give an adequate description of the process by correlation with experiments. The simulations illustrate the effect of the geometry of planetary <span class="hlt">ball</span> mills on the energy entry. In addition the imaging of motion patterns inside a planetary <span class="hlt">ball</span> mill from simulations and video recordings is shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PhDT........94L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PhDT........94L"><span>Investigating <span class="hlt">lightning</span>-to-ionosphere energy coupling based on VLF <span class="hlt">lightning</span> propagation characterization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lay, Erin Hoffmann</p> <p></p> <p>In this dissertation, the capabilities of the World-Wide <span class="hlt">Lightning</span> Location Network (WWLLN) are analyzed in order to study the interactions of <span class="hlt">lightning</span> energy with the lower ionosphere. WWLLN is the first global ground-based <span class="hlt">lightning</span> location network and the first <span class="hlt">lightning</span> detection network that continuously monitors <span class="hlt">lightning</span> around the world in real time. For this reason, a better characterization of the WWLLN could allow many global atmospheric science problems to be addressed, including further investigation into the global electric circuit and global mapping of regions of the lower ionosphere likely to be impacted by strong <span class="hlt">lightning</span> and transient luminous events. This dissertation characterizes the World-Wide Location Network (WWLLN) in terms of detection efficiency, location and timing accuracy, and <span class="hlt">lightning</span> type. This investigation finds excellent timing and location accuracy for WWLLN. It provides the first experimentally-determined estimate of relative global detection efficiency that is used to normalize <span class="hlt">lightning</span> counts based on location. These normalized global <span class="hlt">lightning</span> data from the WWLLN are used to map intense storm regions around the world with high time and spatial resolution as well as to provide information on energetic emissions known as elves and terrestrial gamma-ray flashes (TGFs). This dissertation also improves WWLLN by developing a procedure to provide the first estimate of relative <span class="hlt">lightning</span> stroke radiated energy in the 1-24 kHz frequency range by a global <span class="hlt">lightning</span> detection network. These characterizations and improvements to WWLLN are motivated by the desire to use WWLLN data to address the problem of <span class="hlt">lightning</span>-to-ionosphere energy coupling. Therefore, WWLLN stroke rates are used as input to a model, developed by Professor Mengu Cho at the Kyushu Institute of Technology in Japan, that describes the non-linear effect of <span class="hlt">lightning</span> electromagnetic pulses (EMP) on the ionosphere by accumulating electron density changes resulting</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1320238','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1320238"><span>A Survey of <span class="hlt">Lightning</span> Policy in Selected Division I Colleges</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Walsh, Katie M.; Hanley, Michael J.; Graner, Susanne J.; Beam, Dwayne; Bazluki, Jim</p> <p>1997-01-01</p> <p>Objective: The purpose of this research was to investigate the hazards of <span class="hlt">lightning</span> for participants in outdoor athletics and to determine the existence of, and assess the nature of, <span class="hlt">lightning</span> safety policy at the collegiate level. Design and Setting: We used data from the National Severe Storms <span class="hlt">Laboratory</span> in Norman, Oklahoma, and from a survey of Division I institutions. Subjects: The 48 National Collegiate Athletic Association Division I (football) universities in Florida, Michigan, Pennsylvania, North Carolina, and New York. Measurements: Athletic trainers at all of the selected 48 Division I institutions responded to the telephone survey. Results: Florida, Michigan, Pennsylvania, North Carolina, and New York led the country in <span class="hlt">lightning</span> deaths and injuries from 1959-1994. Only 8% (n = 4) of the institutions surveyed in these states have a written policy regarding <span class="hlt">lightning</span> safety. Conclusions: This study demonstrated the lack of <span class="hlt">lightning</span> safety policy in the surveyed universities and the need for a systematic plan of action to make fields safer for all who are involved in outdoor sport activities. PMID:16558450</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800013445','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800013445"><span>Measurement of Electromagnetic Properties of <span class="hlt">Lightning</span> with 10 Nanosecond Resolution</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Baum, C. E.; Breen, E. L.; Oneill, J. P.; Moore, C. B.; Hall, D. L.</p> <p>1980-01-01</p> <p>Electromagnetic data recorded from <span class="hlt">lightning</span> strikes are presented. The data analysis reveals general characteristics of fast electromagnetic fields measured at the ground including rise times, amplitudes, and time patterns. A look at the electromagnetic structure of <span class="hlt">lightning</span> shows that the shortest rise times in the vicinity of 30 ns are associated with leader leader streamers. <span class="hlt">Lightning</span> location is based on electromagnetic field characteristics and is compared to a nearby sky camera. The fields from both leaders and return strokes were measured and are discussed. The data were obtained during 1978 and 1979 from <span class="hlt">lightning</span> strikes occuring within 5 kilometers of an underground metal instrumentation room located on South Baldy peak near Langmuir <span class="hlt">Laboratory</span>, New Mexico. The computer controlled instrumentation consisted of sensors previously used for measuring the nuclear electromagnetic pulse (EMP) and analog-digital recorders with 10 ns sampling, 256 levels of resolution, and 2 kilobytes of internal memory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19810002018','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19810002018"><span>Electrostatic protection of the solar power satellite and rectenna. Part 2: <span class="hlt">Lightning</span> protection of the rectenna</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1980-01-01</p> <p>Computer simulations and <span class="hlt">laboratory</span> tests were used to evaluate the hazard posed by <span class="hlt">lightning</span> flashes to ground on the Solar Power Satellite rectenna and to make recommendations on a <span class="hlt">lightning</span> protection system for the rectenna. The distribution of <span class="hlt">lightning</span> over the lower 48 of the continental United States was determined, as were the interactions of <span class="hlt">lightning</span> with the rectenna and the modes in which those interactions could damage the rectenna. <span class="hlt">Lightning</span> protection was both required and feasible. Several systems of <span class="hlt">lightning</span> protection were considered and evaluated. These included two systems that employed <span class="hlt">lightning</span> rods of different lengths and placed on top of the rectenna's billboards and a third, distribution companies; it consists of short <span class="hlt">lightning</span> rods all along the length of each billboard that are connected by a horizontal wire above the billboard. The distributed <span class="hlt">lightning</span> protection system afforded greater protection than the other systems considered and was easier to integrate into the rectenna's structural design.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004EOSTr..85..110O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004EOSTr..85..110O"><span><span class="hlt">Lightning</span> Physics and Effects</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Orville, Richard E.</p> <p>2004-03-01</p> <p><span class="hlt">Lightning</span> Physics and Effects is not a <span class="hlt">lightning</span> book; it is a <span class="hlt">lightning</span> encyclopedia. Rarely in the history of science has one contribution covered a subject with such depth and thoroughness as to set the enduring standard for years, perhaps even decades, to come. This contribution covers all aspects of <span class="hlt">lightning</span>, including <span class="hlt">lightning</span> physics, <span class="hlt">lightning</span> protection, and the interaction of <span class="hlt">lightning</span> with a variety of objects and systems as well as the environment. The style of writing is well within the ability of the technical non-expert and anyone interested in <span class="hlt">lightning</span> and its effects. Potential readers will include physicists; engineers working in the power industry, communications, computer, and aviation industries; atmospheric scientists; geophysicists; meteorologists; atmospheric chemists; foresters; ecologists; physicians working in the area of electrical trauma; and, lastly, architects. This comprehensive reference volume contains over 300 illustrations, 70 tables with quantitative information, and over 6000 reference and bibliography entries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140007286','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140007286"><span>A Total <span class="hlt">Lightning</span> Perspective of the 20 May 2013 Moore, Oklahoma Supercell</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stano, Geoffrey T.; Schultz, Christopher J.; Carey, Lawrence D.; MacGorman, Don R.; Calhoun, Kristin M.</p> <p>2014-01-01</p> <p>In the early afternoon of 20 May 2013, a storm initiated to the west-southwest of Newcastle, Oklahoma. This storm would rapidly intensify into the parent supercell of the tornado that struck the city of Moore, Oklahoma. This article describes what contributions total <span class="hlt">lightning</span> observations from the Oklahoma <span class="hlt">Lightning</span> Mapping Array could provide to operational forecasters had these observations been available in real-time. This effort includes a focus on the GOES-R pseudo-geostationary <span class="hlt">lightning</span> mapper demonstration product as well as the NASA SPoRT / Meteorological Development <span class="hlt">Laboratory</span>'s total <span class="hlt">lightning</span> tracking tool. These observations and tools identified several contributions. Two distinct <span class="hlt">lightning</span> jumps at 1908 and 1928 UTC provided a lead time of 19 minutes ahead of severe hail and 26 minutes ahead of the Moore, Oklahoma tornado's touchdown. These observations provide strong situational awareness to forecasters, as the <span class="hlt">lightning</span> jumps are related to the rapid strengthening of the storm's updraft and mesocyclone and serve as a precursor to the stretching of the storm vortex ahead severe weather.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5965181','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5965181"><span><span class="hlt">Lightning</span> Burns and Electrical Trauma in a Couple Simultaneously Struck by <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Eyerly-Webb, Stephanie A.; Solomon, Rachele; Lee, Seong K.; Sanchez, Rafael; Carrillo, Eddy H.; Davare, Dafney L.; Kiffin, Chauniqua; Rosenthal, Andrew</p> <p>2017-01-01</p> <p>More people are struck and killed by <span class="hlt">lightning</span> each year in Florida than any other state in the United States. This report discusses a couple that was simultaneously struck by <span class="hlt">lightning</span> while walking arm-in-arm. Both patients presented with characteristic <span class="hlt">lightning</span> burns and were admitted for hemodynamic monitoring, serum labs, and observation and were subsequently discharged home. Despite the superficial appearance of <span class="hlt">lightning</span> burns, serious internal electrical injuries are common. Therefore, <span class="hlt">lightning</span> strike victims should be admitted and evaluated for cardiac arrhythmias, renal injury, and neurological sequelae.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA01096&hterms=Dark+web&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DDark%2Bweb','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA01096&hterms=Dark+web&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DDark%2Bweb"><span>Jovian <span class="hlt">Lightning</span> and Moonlit Clouds</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1997-01-01</p> <p>Jovian <span class="hlt">lightning</span> and moonlit clouds. These two images, taken 75 minutes apart, show <span class="hlt">lightning</span> storms on the night side of Jupiter along with clouds dimly lit by moonlight from Io, Jupiter's closest moon. The images were taken in visible light and are displayed in shades of red. The images used an exposure time of about one minute, and were taken when the spacecraft was on the opposite side of Jupiter from the Earth and Sun. Bright storms are present at two latitudes in the left image, and at three latitudes in the right image. Each storm was made visible by multiple <span class="hlt">lightning</span> strikes during the exposure. Other Galileo images were deliberately scanned from east to west in order to separate individual flashes. The images show that Jovian and terrestrial <span class="hlt">lightning</span> storms have similar flash rates, but that Jovian <span class="hlt">lightning</span> strikes are a few orders of magnitude brighter in visible light.<p/>The moonlight from Io allows the <span class="hlt">lightning</span> storms to be correlated with visible cloud features. The latitude bands where the storms are seen seem to coincide with the 'disturbed regions' in daylight images, where short-lived chaotic motions push clouds to high altitudes, much like thunderstorms on Earth. The storms in these images are roughly one to two thousand kilometers across, while individual flashes appear hundreds of kilometer across. The <span class="hlt">lightning</span> probably originates from the deep water cloud layer and illuminates a large region of the visible ammonia cloud layer from 100 kilometers below it.<p/>There are several small light and dark patches that are artifacts of data compression. North is at the top of the picture. The images span approximately 50 degrees in latitude and longitude. The lower edges of the images are aligned with the equator. The images were taken on October 5th and 6th, 1997 at a range of 6.6 million kilometers by the Solid State Imaging (SSI) system on NASA's Galileo spacecraft.<p/>The Jet Propulsion <span class="hlt">Laboratory</span>, Pasadena, CA manages the Galileo mission for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMAE33D..01K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMAE33D..01K"><span>How <span class="hlt">Lightning</span> Works Inside Thunderstorms: A Half-Century of <span class="hlt">Lightning</span> Studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Krehbiel, P. R.</p> <p>2015-12-01</p> <p><span class="hlt">Lightning</span> is a fascinating and intriguing natural phenomenon, but the most interesting parts of <span class="hlt">lightning</span> discharges are inside storms where they are obscured from view by the storm cloud. Although clouds are essentially opaque at optical frequencies, they are fully transparent at radio frequencies (RF). This, coupled with the fact that <span class="hlt">lightning</span> produces prodigious RF emissions, has allowed us to image and study <span class="hlt">lightning</span> inside storms using various RF and lower-frequency remote sensing techniques. As in all other scientific disciplines, the technology for conducting the studies has evolved to an incredible extent over the past 50 years. During this time, we have gone from having very little or no knowledge of how <span class="hlt">lightning</span> operates inside storms, to being able to 'see' its detailed structure and development with an increasing degree of spatial and temporal resolution. In addition to studying the discharge processes themselves, <span class="hlt">lightning</span> mapping observations provide valuable information on the electrical charge structure of storms, and on the mechanisms by which storms become strongly electrified. In this presentation we briefly review highlights of previous observations, focussing primarily on the long string of remote-sensing studies I have been involved in. We begin with the study of <span class="hlt">lightning</span> charge centers of cloud-to-ground discharges in central New Mexico in the late 1960s and continue up to the present day with interferometric and 3-dimensional time-of-arrival VHF mapping observations of <span class="hlt">lightning</span> in normally- and anomalously electrified storms. A particularly important aspect of the investigations has been comparative studies of <span class="hlt">lightning</span> in different climatological regimes. We conclude with observations being obtained by a high-speed broadband VHF interferometer, which show in unprecedented detail how individual <span class="hlt">lightning</span> discharges develop inside storms. From combined interferometer and 3-D mapping data, we are beginning to unlock nature's secrets</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040121107','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040121107"><span><span class="hlt">Lightning</span> Instrumentation at KSC</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Colon, Jose L.; Eng, D.</p> <p>2003-01-01</p> <p>This report summarizes <span class="hlt">lightning</span> phenomena with a brief explanation of <span class="hlt">lightning</span> generation and <span class="hlt">lightning</span> activity as related to KSC. An analysis of the instrumentation used at launching Pads 39 A&B for measurements of <span class="hlt">lightning</span> effects is included with alternatives and recommendations to improve the protection system and upgrade the actual instrumentation system. An architecture for a new data collection system to replace the present one is also included. A novel architecture to obtain <span class="hlt">lightning</span> current information from several sensors using only one high speed recording channel while monitoring all sensors to replace the actual manual <span class="hlt">lightning</span> current recorders and a novel device for the protection system are described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080013627&hterms=bateman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbateman','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080013627&hterms=bateman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbateman"><span>A Comparison of <span class="hlt">Lightning</span> Flashes as Observed by the <span class="hlt">Lightning</span> Imaging Sensor and the North Alabama <span class="hlt">Lightning</span> Mapping Array</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bateman, M. G.; Mach, D. M.; McCaul, M. G.; Bailey, J. C.; Christian, H. J.</p> <p>2008-01-01</p> <p>The <span class="hlt">Lightning</span> Imaging Sensor (LIS) aboard the TRMM satellite has been collecting optical <span class="hlt">lightning</span> data since November 1997. A <span class="hlt">Lightning</span> Mapping Array (LMA) that senses VHF impulses from <span class="hlt">lightning</span> was installed in North Alabama in the Fall of 2001. A dataset has been compiled to compare data from both instruments for all times when the LIS was passing over the domain of our LMA. We have algorithms for both instruments to group pixels or point sources into <span class="hlt">lightning</span> flashes. This study presents the comparison statistics of the flash data output (flash duration, size, and amplitude) from both algorithms. We will present the results of this comparison study and show "point-level" data to explain the differences. AS we head closer to realizing a Global <span class="hlt">Lightning</span> Mapper (GLM) on GOES-R, better understanding and ground truth of each of these instruments and their respective flash algorithms is needed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140007319','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140007319"><span><span class="hlt">Lightning</span> Tracking Tool for Assessment of Total Cloud <span class="hlt">Lightning</span> within AWIPS II</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burks, Jason E.; Stano, Geoffrey T.; Sperow, Ken</p> <p>2014-01-01</p> <p>Total <span class="hlt">lightning</span> (intra-cloud and cloud-to-ground) has been widely researched and shown to be a valuable tool to aid real-time warning forecasters in the assessment of severe weather potential of convective storms. The trend of total <span class="hlt">lightning</span> has been related to the strength of a storm's updraft. Therefore a rapid increase in total <span class="hlt">lightning</span> signifies the strengthening of the parent thunderstorm. The assessment of severe weather potential occurs in a time limited environment and therefore constrains the use of total <span class="hlt">lightning</span>. A tool has been developed at NASA's Short-term Prediction Research and Transition (SPoRT) Center to assist in quickly analyzing the total <span class="hlt">lightning</span> signature of multiple storms. The development of this tool comes as a direct result of forecaster feedback from numerous assessments requesting a real-time display of the time series of total <span class="hlt">lightning</span>. This tool also takes advantage of the new architecture available within the AWIPS II environment. SPoRT's <span class="hlt">lightning</span> tracking tool has been tested in the Hazardous Weather Testbed (HWT) Spring Program and significant changes have been made based on the feedback. In addition to the updates in response to the HWT assessment, the <span class="hlt">lightning</span> tracking tool may also be extended to incorporate other requested displays, such as the intra-cloud to cloud-to-ground ratio as well as incorporate the <span class="hlt">lightning</span> jump algorithm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19790010865','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790010865"><span>High current <span class="hlt">lightning</span> test of space shuttle external tank <span class="hlt">lightning</span> protection system</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mumme, E.; Anderson, A.; Schulte, E. H.</p> <p>1977-01-01</p> <p>During lift-off, the shuttle launch vehicle (external tank, solid rocket booster and orbiter) may be subjected to a <span class="hlt">lightning</span> strike. Tests of a proposed <span class="hlt">lightning</span> protection method for the external tank and development materials which were subjected to simulated <span class="hlt">lightning</span> strikes are described. Results show that certain of the high resistant paint strips performed remarkably well in diverting the 50 kA <span class="hlt">lightning</span> strikes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150016925','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150016925"><span><span class="hlt">Ball</span> Screw Actuator Including a Compliant <span class="hlt">Ball</span> Screw Stop</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wingett, Paul T. (Inventor); Hanlon, Casey (Inventor)</p> <p>2015-01-01</p> <p>An actuator includes a <span class="hlt">ball</span> nut, a <span class="hlt">ball</span> screw, and a <span class="hlt">ball</span> screw stop. The <span class="hlt">ball</span> nut is adapted to receive an input torque and in response rotates and supplies a drive force. The <span class="hlt">ball</span> screw extends through the <span class="hlt">ball</span> nut and has a first end and a second end. The <span class="hlt">ball</span> screw receives the drive force from the <span class="hlt">ball</span> nut and in response selectively translates between a retract position and a extend position. The <span class="hlt">ball</span> screw stop is mounted on the <span class="hlt">ball</span> screw proximate the first end to translate therewith. The <span class="hlt">ball</span> screw stop engages the <span class="hlt">ball</span> nut when the <span class="hlt">ball</span> screw is in the extend position, translates, with compliance, a predetermined distance toward the first end upon engaging the <span class="hlt">ball</span> nut, and prevents further rotation of the <span class="hlt">ball</span> screw upon translating the predetermined distance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170002889','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170002889"><span><span class="hlt">Ball</span> Screw Actuator Including a Compliant <span class="hlt">Ball</span> Screw Stop</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wingett, Paul T. (Inventor); Hanlon, Casey (Inventor)</p> <p>2017-01-01</p> <p>An actuator includes a <span class="hlt">ball</span> nut, a <span class="hlt">ball</span> screw, and a <span class="hlt">ball</span> screw stop. The <span class="hlt">ball</span> nut is adapted to receive an input torque and in response rotates and supplies a drive force. The <span class="hlt">ball</span> screw extends through the <span class="hlt">ball</span> nut and has a first end and a second end. The <span class="hlt">ball</span> screw receives the drive force from the <span class="hlt">ball</span> nut and in response selectively translates between a retract position and a extend position. The <span class="hlt">ball</span> screw stop is mounted on the <span class="hlt">ball</span> screw proximate the first end to translate therewith. The <span class="hlt">ball</span> screw stop engages the <span class="hlt">ball</span> nut when the <span class="hlt">ball</span> screw is in the extend position, translates, with compliance, a predetermined distance toward the first end upon engaging the <span class="hlt">ball</span> nut, and prevents further rotation of the <span class="hlt">ball</span> screw upon translating the predetermined distance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29087928','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29087928"><span>Case Report: Mass Casualty <span class="hlt">Lightning</span> Strike at Ranger Training Camp.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Thompson, Shannon N; Wilson, Zachary W; Cole, Christopher B; Kennedy, Andrew R; Aycock, Ryan D</p> <p>2017-05-01</p> <p>Although <span class="hlt">lightning</span> strikes are a rare occurrence, their significance cannot be ignored given military operations in the field during all types of weather. With proper medical management, patients with <span class="hlt">lightning</span> injuries can return to duty. Information for this case report comes from eyewitness account at the 6th Ranger Training Battalion and from review of physician documentation from the 96th Medical Group, Eglin Air Force Base, Florida. A <span class="hlt">lightning</span> strike injured 44 Ranger School participants during a training exercise on August 12, 2015, at Camp Rudder, Florida. These patients were triaged in the field and transported to emergency department of Eglin Air Force Base. Of the 44 casualties, 20 were admitted. All were returned to duty the following day. One patient had cardiac arrest. This patient, along with two others, was admitted to the intensive care unit. Seventeen other patients were admitted for observation for rhabdomyolysis and/or cardiac arrhythmias. One patient was admitted with suspected acute kidney injury indicated by an elevated creatinine. All patients, including those admitted to the intensive care unit, were released on the day following the <span class="hlt">lightning</span> strike without restrictions and were allowed to return to duty with increased medical monitoring. This case report highlights the need for proper triage and recognition of <span class="hlt">lightning</span> strike injury, coordination of care between field operations and emergency department personnel, and close follow-up for patients presenting with <span class="hlt">lightning</span> injury. Symptoms, physical exam, and <span class="hlt">laboratory</span> findings from rigorous training can be difficult to distinguish from those resulting from <span class="hlt">lightning</span> injury. Secondary injuries resulting from blunt trauma from falls may have been prevented by the use of the <span class="hlt">lightning</span> strike posture. Further analysis of procedures and standard operating protocols to mitigate risk during thunderstorms may be required to prevent <span class="hlt">lightning</span>'s effects on large groups of military personnel</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AtmRe.197..255L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AtmRe.197..255L"><span>Spatio-temporal dimension of <span class="hlt">lightning</span> flashes based on three-dimensional <span class="hlt">Lightning</span> Mapping Array</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>López, Jesús A.; Pineda, Nicolau; Montanyà, Joan; Velde, Oscar van der; Fabró, Ferran; Romero, David</p> <p>2017-11-01</p> <p>3D mapping system like the LMA - <span class="hlt">Lightning</span> Mapping Array - are a leap forward in <span class="hlt">lightning</span> observation. LMA measurements has lead to an improvement on the analysis of the fine structure of <span class="hlt">lightning</span>, allowing to characterize the duration and maximum extension of the cloud fraction of a <span class="hlt">lightning</span> flash. During several years of operation, the first LMA deployed in Europe has been providing a large amount of data which now allows a statistical approach to compute the full duration and horizontal extension of the in-cloud phase of a <span class="hlt">lightning</span> flash. The "Ebro <span class="hlt">Lightning</span> Mapping Array" (ELMA) is used in the present study. Summer and winter lighting were analyzed for seasonal periods (Dec-Feb and Jun-Aug). A simple method based on an ellipse fitting technique (EFT) has been used to characterize the spatio-temporal dimensions from a set of about 29,000 <span class="hlt">lightning</span> flashes including both summer and winter events. Results show an average <span class="hlt">lightning</span> flash duration of 440 ms (450 ms in winter) and a horizontal maximum length of 15.0 km (18.4 km in winter). The uncertainties for summer <span class="hlt">lightning</span> lengths were about ± 1.2 km and ± 0.7 km for the mean and median values respectively. In case of winter <span class="hlt">lightning</span>, the level of uncertainty reaches up to 1 km and 0.7 km of mean and median value. The results of the successful correlation of CG discharges with the EFT method, represent 6.9% and 35.5% of the total LMA flashes detected in summer and winter respectively. Additionally, the median value of <span class="hlt">lightning</span> lengths calculated through this correlative method was approximately 17 km for both seasons. On the other hand, the highest median ratios of <span class="hlt">lightning</span> length to CG discharges in both summer and winter were reported for positive CG discharges.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA239988','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA239988"><span>A Survey of Laser <span class="hlt">Lightning</span> Rod Techniques</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1991-08-21</p> <p>impossibility of the LLR concept. 4 REFERENCES 1. Hagen, 1969: "Diffraction-limited high irradiance Nd- glass laser system, J. Appl. Phys., 40, 511-516. 2. Greig...study", Air Force Flight Dynamics <span class="hlt">Laboratory</span>,, Technical Report AFFDL-TR-78-60. AD A063 847. 8. Schubert, C.N., Jr. and J.R. Lippert , 1979...pp. 132-135. 9. Lippert , J.R.,1978: "Laser-Induced <span class="hlt">Lightning</span> Concept Exper- iment", Air Force Flight Dynamics <span class="hlt">Laboratory</span>, Technical Report AFFDL-TR</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950057365&hterms=paper+airplanes&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dpaper%2Bairplanes','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950057365&hterms=paper+airplanes&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dpaper%2Bairplanes"><span><span class="hlt">Lightning</span> protection technology for small general aviation composite material aircraft</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Plumer, J. A.; Setzer, T. E.; Siddiqi, S.</p> <p>1993-01-01</p> <p>An on going NASA (Small Business Innovative Research) SBIR Phase II design and development program will produce the first <span class="hlt">lightning</span> protected, fiberglass, General Aviation aircraft that is available as a kit. The results obtained so far in development testing of typical components of the aircraft kit, such as the wing and fuselage panels indicate that the <span class="hlt">lightning</span> protection design methodology and materials chosen are capable of protecting such small composite airframes from <span class="hlt">lightning</span> puncture and structural damage associated with severe threat <span class="hlt">lightning</span> strikes. The primary objective of the program has been to develop a lightening protection design for full scale test airframe and verify its adequacy with full scale <span class="hlt">laboratory</span> testing, thus enabling production and sale of owner-built, <span class="hlt">lightning</span>-protected, Stoddard-Hamilton Aircraft, Inc. Glasair II airplanes. A second objective has been to provide <span class="hlt">lightning</span> protection design guidelines for the General Aviation industry, and to enable these airplanes to meet lightening protection requirements for certification of small airplanes. This paper describes the protection design approaches and development testing results obtained thus far in the program, together with design methodology which can achieve the design goals listed above. The presentation of this paper will also include results of some of the full scale verification tests, which will have been completed by the time of this conference.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100033571','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100033571"><span>Situational <span class="hlt">Lightning</span> Climatologies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bauman, William; Crawford, Winifred</p> <p>2010-01-01</p> <p>Research has revealed distinct spatial and temporal distributions of <span class="hlt">lightning</span> occurrence that are strongly influenced by large-scale atmospheric flow regimes. It was believed there were two flow systems, but it has been discovered that actually there are seven distinct flow regimes. The Applied Meteorology Unit (AMU) has recalculated the <span class="hlt">lightning</span> climatologies for the Shuttle Landing Facility (SLF), and the eight airfields in the National Weather Service in Melbourne (NWS MLB) County Warning Area (CWA) using individual <span class="hlt">lightning</span> strike data to improve the accuracy of the climatologies. The software determines the location of each CG <span class="hlt">lightning</span> strike with 5-, 10-, 20-, and 30-nmi (.9.3-, 18.5-, 37-, 55.6-km) radii from each airfield. Each CG <span class="hlt">lightning</span> strike is binned at 1-, 3-, and 6-hour intervals at each specified radius. The software merges the CG <span class="hlt">lightning</span> strike time intervals and distance with each wind flow regime and creates probability statistics for each time interval, radii, and flow regime, and stratifies them by month and warm season. The AMU also updated the graphical user interface (GUI) with the new data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23799482','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23799482"><span><span class="hlt">Lightning</span> burns.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Russell, Katie W; Cochran, Amalia L; Mehta, Sagar T; Morris, Stephen E; McDevitt, Marion C</p> <p>2014-01-01</p> <p>We present the case of a <span class="hlt">lightning</span>-strike victim. This case illustrates the importance of in-field care, appropriate referral to a burn center, and the tendency of <span class="hlt">lightning</span> burns to progress to full-thickness injury.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/959070','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/959070"><span>Indirect <span class="hlt">Lightning</span> Safety Assessment Methodology</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Ong, M M; Perkins, M P; Brown, C G</p> <p>2009-04-24</p> <p><span class="hlt">Lightning</span> is a safety hazard for high-explosives (HE) and their detonators. In the However, the current flowing from the strike point through the rebar of the building The methodology for estimating the risk from indirect lighting effects will be presented. It has two parts: a method to determine the likelihood of a detonation given a <span class="hlt">lightning</span> strike, and an approach for estimating the likelihood of a strike. The results of these two parts produce an overall probability of a detonation. The probability calculations are complex for five reasons: (1) <span class="hlt">lightning</span> strikes are stochastic and relatively rare, (2) the quality ofmore » the Faraday cage varies from one facility to the next, (3) RF coupling is inherently a complex subject, (4) performance data for abnormally stressed detonators is scarce, and (5) the arc plasma physics is not well understood. Therefore, a rigorous mathematical analysis would be too complex. Instead, our methodology takes a more practical approach combining rigorous mathematical calculations where possible with empirical data when necessary. Where there is uncertainty, we compensate with conservative approximations. The goal is to determine a conservative estimate of the odds of a detonation. In Section 2, the methodology will be explained. This report will discuss topics at a high-level. The reasons for selecting an approach will be justified. For those interested in technical details, references will be provided. In Section 3, a simple hypothetical example will be given to reinforce the concepts. While the methodology will touch on all the items shown in Figure 1, the focus of this report is the indirect effect, i.e., determining the odds of a detonation from given EM fields. Professor Martin Uman from the University of Florida has been characterizing and defining extreme <span class="hlt">lightning</span> strikes. Using Professor Uman's research, Dr. Kimball Merewether at Sandia National <span class="hlt">Laboratory</span> in Albuquerque calculated the EM fields inside a Faraday</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.weather.gov/safety/lightning','NIH-MEDLINEPLUS'); return false;" href="https://www.weather.gov/safety/lightning"><span><span class="hlt">Lightning</span> Safety Tips and Resources</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Safety Brochure U.S. <span class="hlt">Lightning</span> Deaths in 2018 : 5 Youtube: <span class="hlt">Lightning</span> Safety for the Deaf and Hard of ... for Hard of Hearing: jpg , high res png YouTube: <span class="hlt">Lightning</span> Safety Tips <span class="hlt">Lightning</span> Safety When Working Outdoors : ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930040920&hterms=quantitative+research&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dquantitative%2Bresearch','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930040920&hterms=quantitative+research&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dquantitative%2Bresearch"><span>MSFC shuttle <span class="hlt">lightning</span> research</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Vaughan, Otha H., Jr.</p> <p>1993-01-01</p> <p>The shuttle mesoscale <span class="hlt">lightning</span> experiment (MLE), flown on earlier shuttle flights, and most recently flown on the following space transportation systems (STS's), STS-31, -32, -35, -37, -38, -40, -41, and -48, has continued to focus on obtaining additional quantitative measurements of <span class="hlt">lightning</span> characteristics and to create a data base for use in demonstrating observation simulations for future spaceborne <span class="hlt">lightning</span> mapping systems. These flights are also providing design criteria data for the design of a proposed shuttle MLE-type <span class="hlt">lightning</span> research instrument called mesoscale <span class="hlt">lightning</span> observational sensors (MELOS), which are currently under development here at MSFC.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/380319','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/380319"><span>New mechanism for <span class="hlt">lightning</span> initiation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Roussel-Dupre, R.; Buchwald, M.; Gurevich, A.</p> <p>1996-10-01</p> <p>This is the final report of a three-year, <span class="hlt">Laboratory</span>-Directed Research and Development (LDRD) project at the Los Alamos National <span class="hlt">Laboratory</span> (LANL). To distinguish radio-frequency (rf) signals generated by <span class="hlt">lightning</span> from the electromagnetic pulse produced by a nuclear explosion, it is necessary to understand the fundamental nature of thunderstorm discharges. The recent debate surrounding the origin of transionospheric pulse pairs (TIPPs) detected by the BLACKBEARD experiment aboard the ALEXIS satellite illustrates this point. We have argued that TIPP events could originate from the upward propagating discharges recently identified by optical images taken from the ground, from airplanes, and from the spacemore » shuttle. In addition, the Gamma Ray Observatory (GRO) measurements of x-ray bursts originating from thunderstorms are almost certainly associated with these upward propagating discharges. When taken together, these three measurements point directly to the runaway electron mechanism as the source of the upward discharges. The primary goal of this research effort was to identify the specific role played by the runaway-air-breakdown mechanism in the general area of thunderstorm electricity and in so doing develop <span class="hlt">lightning</span> models that predict the optical, rf, and x-ray emissions that are observable from space.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19860065522&hterms=Measuring+strategic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DMeasuring%2Bstrategic','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19860065522&hterms=Measuring+strategic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DMeasuring%2Bstrategic"><span>A wide bandwidth electrostatic field sensor for <span class="hlt">lightning</span> research</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zaepfel, K. P.</p> <p>1986-01-01</p> <p>Data obtained from UHF Radar observation of direct-<span class="hlt">lightning</span> strikes to the NASA F-106B airplane have indicated that most of the 690 strikes acquired during direct-strike <span class="hlt">lightning</span> tests were triggered by the aircraft. As an aid in understanding the triggered <span class="hlt">lightning</span> process, a wide bandwidth electric field measuring system was designed for the F-106B by implementing a clamped-detection signal processing concept originated at the Air Force Cambridge Research Lab in 1953. The detection scheme combines the signals from complementary stator pairs clamped to zero volts at the exact moment when each stator pair is maximally shielded by the rotor, a process that restores the dc level lost by the charge amplifier. The new system was implemented with four shutter-type field mills located at strategic points on the airplane. The bandwidth of the new system was determined in the <span class="hlt">laboratory</span> to be from dc to over 100 Hz, whereas past designs had upper limits of 10 Hz to 100 Hz. To obtain the undisturbed electric field vector and total aircraft charge, the airborne field mill system is calibrated by using techniques involving results from ground and flight calibrations of the F-106B, <span class="hlt">laboratory</span> tests of a metallized model, and a finite-difference time-domain electromagnetic computer code.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890010412','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890010412"><span>A wide bandwidth electrostatic field sensor for <span class="hlt">lightning</span> research</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zaepfel, Klaus P.</p> <p>1989-01-01</p> <p>Data obtained from UHF radar observation of direct-<span class="hlt">lightning</span> strikes to the NASA F-106B aircraft have indicated that most of the 690 strikes acquired during direct-strike <span class="hlt">lightning</span> tests were triggered by the aircraft. As an aid in understanding the triggered <span class="hlt">lightning</span> process, a wide bandwidth electric field measuring system was designed for the F-106B by implementing a clamped-detection signal processing concept originated at the Air Force Cambridge Research Lab in 1953. The detection scheme combines the signals from complementary stator pairs clamped to zero bolts at the exact moment when each stator pair is maximally shielded by the rotor, a process that restores the dc level lost by the charge amplifier. The system was implemented with four shutter-type field mills located at strategic points on the aircraft. The bandwidth of the system was determined in the <span class="hlt">laboratory</span> to be from dc to over 100 Hz, whereas past designs had upper limits of 10 to 100 Hz. To obtain the undisturbed electric field vector and total aircraft charge, the airborne field mill system is calibrated by using techniques involving results from ground and flight calibrations of the F-106B, <span class="hlt">laboratory</span> tests of a metallized model, and a finite difference time-domain electromagnetic computer code.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850000462&hterms=stroke&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dstroke','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850000462&hterms=stroke&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dstroke"><span>Plotting <span class="hlt">Lightning</span>-Stroke Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tatom, F. B.; Garst, R. A.</p> <p>1986-01-01</p> <p>Data on <span class="hlt">lightning</span>-stroke locations become easier to correlate with cloudcover maps with aid of new graphical treatment. Geographic region divided by grid into array of cells. Number of <span class="hlt">lightning</span> strokes in each cell tabulated, and value representing density of <span class="hlt">lightning</span> strokes assigned to each cell. With contour-plotting routine, computer draws contours of <span class="hlt">lightning</span>-stroke density for region. Shapes of contours compared directly with shapes of storm cells.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20090017495&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DG%2526T','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20090017495&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DG%2526T"><span>The North Alabama <span class="hlt">Lightning</span> Warning Product</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Buechler, Dennis E.; Blakeslee, R. J.; Stano, G. T.</p> <p>2009-01-01</p> <p>The North Alabama <span class="hlt">Lightning</span> Mapping Array NALMA has been collecting total <span class="hlt">lightning</span> data on storms in the Tennessee Valley region since 2001. Forecasters from nearby National Weather Service (NWS) offices have been ingesting this data for display with other AWIPS products. The current <span class="hlt">lightning</span> product used by the offices is the <span class="hlt">lightning</span> source density plot. The new product provides a probabalistic, short-term, graphical forecast of the probability of <span class="hlt">lightning</span> activity occurring at 5 min intervals over the next 30 minutes . One of the uses of the current <span class="hlt">lightning</span> source density product by the Huntsville National Weather Service Office is to identify areas of potential for cloud-to-ground flashes based on where LMA total <span class="hlt">lightning</span> is occurring. This product quantifies that observation. The <span class="hlt">Lightning</span> Warning Product is derived from total <span class="hlt">lightning</span> observations from the Washington, D.C. (DCLMA) and North Alabama <span class="hlt">Lightning</span> Mapping Arrays and cloud-to-ground <span class="hlt">lightning</span> flashes detected by the National <span class="hlt">Lightning</span> Detection Network (NLDN). Probability predictions are provided for both intracloud and cloud-to-ground flashes. The gridded product can be displayed on AWIPS workstations in a manner similar to that of the <span class="hlt">lightning</span> source density product.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMAE31A0273A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMAE31A0273A"><span>Infrasound Observations from <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arechiga, R. O.; Johnson, J. B.; Edens, H. E.; Thomas, R. J.; Jones, K. R.</p> <p>2008-12-01</p> <p>To provide additional insight into the nature of <span class="hlt">lightning</span>, we have investigated its infrasound manifestations. An array of three stations in a triangular configuration, with three sensors each, was deployed during the Summer of 2008 (July 24 to July 28) in the Magdalena mountains of New Mexico, to monitor infrasound (below 20 Hz) sources due to <span class="hlt">lightning</span>. Hyperbolic formulations of time of arrival (TOA) measurements and interferometric techniques were used to locate <span class="hlt">lightning</span> sources occurring over and outside the network. A comparative analysis of simultaneous <span class="hlt">Lightning</span> Mapping Array (LMA) data and infrasound measurements operating in the same area was made. The LMA locates the sources of impulsive RF radiation produced by <span class="hlt">lightning</span> flashes in three spatial dimensions and time, operating in the 60 - 66 MHz television band. The comparison showed strong evidence that <span class="hlt">lightning</span> does produce infrasound. This work is a continuation of the study of the frequency spectrum of thunder conducted by Holmes et al., who reported measurements of infrasound frequencies. The integration of infrasound measurements with RF source localization by the LMA shows great potential for improved understanding of <span class="hlt">lightning</span> processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020090858','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020090858"><span>Bowling <span class="hlt">Ball</span> Spotting</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1985-01-01</p> <p>Exactatron, an accurate weighing and spotting system in bowling <span class="hlt">ball</span> manufacture, was developed by Ebonite International engineers with the assistance of a NASA computer search which identified Jet Propulsion <span class="hlt">Laboratory</span> (JPL) technology. The JPL research concerned a means of determining the center of an object's mass, and an apparatus for measuring liquid viscosity, enabling Ebonite to identify the exact spotting of the drilling point for top weighting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=The+AND+lightning&pg=2&id=EJ464567','ERIC'); return false;" href="https://eric.ed.gov/?q=The+AND+lightning&pg=2&id=EJ464567"><span>A <span class="hlt">Lightning</span> Safety Primer for Camps.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Attarian, Aram</p> <p>1992-01-01</p> <p>Provides the following information about <span class="hlt">lightning</span>, which is necessary for camp administrators and staff: (1) warning signs of <span class="hlt">lightning</span>; (2) dangers of <span class="hlt">lightning</span>; (3) types of <span class="hlt">lightning</span> injuries; (4) prevention of <span class="hlt">lightning</span> injury; and (5) helpful training tips. (KS)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040085918&hterms=probability+statistical+inference&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dprobability%2Bstatistical%2Binference','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040085918&hterms=probability+statistical+inference&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dprobability%2Bstatistical%2Binference"><span>Multivariate Statistical Inference of <span class="hlt">Lightning</span> Occurrence, and Using <span class="hlt">Lightning</span> Observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Boccippio, Dennis</p> <p>2004-01-01</p> <p>Two classes of multivariate statistical inference using TRMM <span class="hlt">Lightning</span> Imaging Sensor, Precipitation Radar, and Microwave Imager observation are studied, using nonlinear classification neural networks as inferential tools. The very large and globally representative data sample provided by TRMM allows both training and validation (without overfitting) of neural networks with many degrees of freedom. In the first study, the flashing / or flashing condition of storm complexes is diagnosed using radar, passive microwave and/or environmental observations as neural network inputs. The diagnostic skill of these simple <span class="hlt">lightning/no-lightning</span> classifiers can be quite high, over land (above 80% Probability of Detection; below 20% False Alarm Rate). In the second, passive microwave and <span class="hlt">lightning</span> observations are used to diagnose radar reflectivity vertical structure. A priori diagnosis of hydrometeor vertical structure is highly important for improved rainfall retrieval from either orbital radars (e.g., the future Global Precipitation Mission "mothership") or radiometers (e.g., operational SSM/I and future Global Precipitation Mission passive microwave constellation platforms), we explore the incremental benefit to such diagnosis provided by <span class="hlt">lightning</span> observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19930005198','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19930005198"><span>Evidence for <span class="hlt">lightning</span> on Venus</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Strangeway, R. J.</p> <p>1992-01-01</p> <p><span class="hlt">Lightning</span> is an interesting phenomenon both for atmospheric and ionospheric science. At the Earth <span class="hlt">lightning</span> is generated in regions where there is strong convection. <span class="hlt">Lightning</span> also requires the generation of large charge-separation electric fields. The energy dissipated in a <span class="hlt">lightning</span> discharge can, for example, result in chemical reactions that would not normally occur. From an ionospheric point of view, <span class="hlt">lightning</span> generates a broad spectrum of electromagnetic radiation. This radiation can propagate through the ionosphere as whistler mode waves, and at the Earth the waves propagate to high altitudes in the plasmasphere where they can cause energetic particle precipitation. The atmosphere and ionosphere of Venus are quite different from those on the Earth, and the presence of <span class="hlt">lightning</span> at Venus has important consequences for our knowledge of why <span class="hlt">lightning</span> occurs and how the energy is dissipated in the atmosphere and ionosphere. As discussed here, it now appears that <span class="hlt">lightning</span> occurs in the dusk local time sector at Venus.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815451H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815451H"><span>Structural and erosive Effects of <span class="hlt">Lightning</span> on Sandstone: An Experimental Investigation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Haddad, Houssam; Ebert, Matthias; Kenkmann, Thomas; Thoma, Klaus; Nau, Siegfried; Schäfer, Frank</p> <p>2016-04-01</p> <p>Recent prognoses predict an average temperature increase of the world's climate of about 1.5 to 2 °C until the end of 21st century. This change leads not only to a rise of the sea level but also to an increase of thunderstorms and therefore to a ~25 percent increase of cloud-to-ground <span class="hlt">lightning</span> events (Romps et al., 2014). It is known that (i) <span class="hlt">lightning</span> strikes are able to fragment surface rocks, which probably influences the erosion rates at exposed mountain areas (Knight and Grab, 2014), and (ii) the efficiency of the process increases due to the predicted climate change. However, our knowledge about the electro-mechanical destruction of rocks caused by high energetic <span class="hlt">lightning</span> is incomplete. In this study, <span class="hlt">laboratory</span> experiments of <span class="hlt">lightning</span> strikes were performed in order to understand the fragmentation of rocks and changes to landforms by <span class="hlt">lightning</span>. The artificial <span class="hlt">lightning</span> with known electric current was simulated by a high-current generator in the <span class="hlt">laboratories</span> of the Fraunhofer Ernst-Mach Institute for High-Speed Dynamics (Freiburg, Germany). Different currents were transferred over a distance of ~2mm onto water-saturated sandstones by using a copper cathode (3 experiments; U, I, E, Δt: 6 kV, 200 kA, 0.1 MJ, 0.7 ms; 9 kV, 300 kA, 0.19 MJ, 0.9 ms; 12 kV, 400 kA, 0.35 MJ, 0.5 ms). The damaged sandstones were investigated by means of optical and electron-optical methods as well as by X-ray computed tomography to determine the modes and dimensions of melting and fragmentation. Digital elevation models of craters formed by ejection were obtained by white-light interferometry. The <span class="hlt">lightning</span> experiments produced small craters (~1 cm in diameter, ~0.5 cm depth) which surfaces and sub-surfaces consist of silicate melts (molten quartz and phyllosilicates). The silicate melts reach several hundred micrometers into the sub-surface and resemble the appearance of natural fulgurites. Melting of quartz indicate temperatures of at least 1650 °C. In addition, the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Electric+AND+discharge&id=EJ081790','ERIC'); return false;" href="https://eric.ed.gov/?q=Electric+AND+discharge&id=EJ081790"><span>Thunderclouds and <span class="hlt">Lightning</span> Conductors</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Martin, P. F.</p> <p>1973-01-01</p> <p>Discusses the historical background of the development of <span class="hlt">lightning</span> conductors, describes the nature of thunderclouds and the <span class="hlt">lightning</span> flash, and provides a calculation of the electric field under a thundercloud. Also discussed are point discharge currents and the attraction theory of the <span class="hlt">lightning</span> conductor. (JR)</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PlST...19l5301Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PlST...19l5301Y"><span>Experimental and analytical investigation on metal damage suffered from simulated <span class="hlt">lightning</span> currents</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yakun, LIU; Zhengcai, FU; Quanzhen, LIU; Baoquan, LIU; Anirban, GUHA</p> <p>2017-12-01</p> <p>The damage of two typical metal materials, Al alloy 3003 and steel alloy Q235B, subjected to four representative <span class="hlt">lightning</span> current components are investigated by <span class="hlt">laboratory</span> and analytical studies to provide fundamental data for <span class="hlt">lightning</span> protection. The four <span class="hlt">lightning</span> components simulating the natural <span class="hlt">lightning</span> consist of the first return stroke, the continuing current of interval stroke, the long continuing current, and the subsequent stroke, with amplitudes 200 kA, 8 kA, 400 A, and 100 kA, respectively. The damage depth and area suffered from different <span class="hlt">lightning</span> components are measured by the ultrasonic scanning system. And the temperature rise is measured by the thermal imaging camera. The results show that, for both Al 3003 and steel Q235B, the first return stroke component results in the largest damage area with damage depth 0.02 mm uttermost. The long continuing current component leads to the deepest damage depth of 3.3 mm for Al 3003 and much higher temperature rise than other components. The correlation analysis between damage results and <span class="hlt">lightning</span> parameters indicates that the damage depth has a positive correlation with charge transfer. The damage area is mainly determined by the current amplitude and the temperature rise increases linearly with the charge transfer larger.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22215021','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22215021"><span><span class="hlt">Lightning</span> safety of animals.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gomes, Chandima</p> <p>2012-11-01</p> <p>This paper addresses a concurrent multidisciplinary problem: animal safety against <span class="hlt">lightning</span> hazards. In regions where <span class="hlt">lightning</span> is prevalent, either seasonally or throughout the year, a considerable number of wild, captive and tame animals are injured due to <span class="hlt">lightning</span> generated effects. The paper discusses all possible injury mechanisms, focusing mainly on animals with commercial value. A large number of cases from several countries have been analyzed. Economically and practically viable engineering solutions are proposed to address the issues related to the <span class="hlt">lightning</span> threats discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21909737','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21909737"><span>[<span class="hlt">Lightning</span> strikes and <span class="hlt">lightning</span> injuries in prehospital emergency medicine. Relevance, results, and practical implications].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hinkelbein, J; Spelten, O; Wetsch, W A</p> <p>2013-01-01</p> <p>Up to 32.2% of patients in a burn center suffer from electrical injuries. Of these patients, 2-4% present with <span class="hlt">lightning</span> injuries. In Germany, approximately 50 people per year are injured by a <span class="hlt">lightning</span> strike and 3-7 fatally. Typically, people involved in outdoor activities are endangered and affected. A <span class="hlt">lightning</span> strike usually produces significantly higher energy doses as compared to those in common electrical injuries. Therefore, injury patterns vary significantly. Especially in high voltage injuries and <span class="hlt">lightning</span> injuries, internal injuries are of special importance. Mortality ranges between 10 and 30% after a <span class="hlt">lightning</span> strike. Emergency medical treatment is similar to common electrical injuries. Patients with <span class="hlt">lightning</span> injuries should be transported to a regional or supraregional trauma center. In 15% of all cases multiple people may be injured. Therefore, it is of outstanding importance to create emergency plans and evacuation plans in good time for mass gatherings endangered by possible <span class="hlt">lightning</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140008582','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140008582"><span><span class="hlt">Lightning</span> Jump Algorithm Development for the GOES·R Geostationary <span class="hlt">Lightning</span> Mapper</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schultz. E.; Schultz. C.; Chronis, T.; Stough, S.; Carey, L.; Calhoun, K.; Ortega, K.; Stano, G.; Cecil, D.; Bateman, M.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20140008582'); toggleEditAbsImage('author_20140008582_show'); toggleEditAbsImage('author_20140008582_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20140008582_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20140008582_hide"></p> <p>2014-01-01</p> <p>Current work on the <span class="hlt">lightning</span> jump algorithm to be used in GOES-R Geostationary <span class="hlt">Lightning</span> Mapper (GLM)'s data stream is multifaceted due to the intricate interplay between the storm tracking, GLM proxy data, and the performance of the <span class="hlt">lightning</span> jump itself. This work outlines the progress of the last year, where analysis and performance of the <span class="hlt">lightning</span> jump algorithm with automated storm tracking and GLM proxy data were assessed using over 700 storms from North Alabama. The cases analyzed coincide with previous semi-objective work performed using total <span class="hlt">lightning</span> mapping array (LMA) measurements in Schultz et al. (2011). Analysis shows that key components of the algorithm (flash rate and sigma thresholds) have the greatest influence on the performance of the algorithm when validating using severe storm reports. Automated objective analysis using the GLM proxy data has shown probability of detection (POD) values around 60% with false alarm rates (FAR) around 73% using similar methodology to Schultz et al. (2011). However, when applying verification methods similar to those employed by the National Weather Service, POD values increase slightly (69%) and FAR values decrease (63%). The relationship between storm tracking and <span class="hlt">lightning</span> jump has also been tested in a real-time framework at NSSL. This system includes fully automated tracking by radar alone, real-time LMA and radar observations and the <span class="hlt">lightning</span> jump. Results indicate that the POD is strong at 65%. However, the FAR is significantly higher than in Schultz et al. (2011) (50-80% depending on various tracking/<span class="hlt">lightning</span> jump parameters) when using storm reports for verification. Given known issues with Storm Data, the performance of the real-time jump algorithm is also being tested with high density radar and surface observations from the NSSL Severe Hazards Analysis & Verification Experiment (SHAVE).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMAE31A0420A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMAE31A0420A"><span>Acoustic vs Interferometric Measurements of <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arechiga, R. O.; Erives, H.; Sonnenfeld, R. G.; Stanley, M. A.; Rison, W.; Thomas, R. J.; Edens, H. E.; Lapierre, J. L.; Stock, M.; Jensen, D.; Morris, K.</p> <p>2015-12-01</p> <p>During the summer of 2015 we acquired acoustic and RF data on severalflashes from thunderstorms over Fort Morgan CO. and Langmuir Laboratoryin the Magdalena mountains of central New Mexico. The acoustic arrayswere located at a distance of roughly 150 m from the interferometers.<span class="hlt">Lightning</span> mapping array and slow antenna data were also obtained. Theacoustic arrays consist of arrays of five audio-range and six infrasoundmicrophones operating at 50 KHz and 1 KHz respectively. The lightninginterferometer at Fort Morgan CO. consists of three flat-plate, 13" diameterantennas at the vertices of an equilateral 50 m per side triangle. Theinterferometer at Langmuir <span class="hlt">Laboratory</span> consists of three 13" dishes separatedby about 15 m. Both interferometers, operating at 180 Megasamples persecond, use the analysis software and digitizer hardware pioneered byStanley, Stock et al. The high data rate allows for excellent spatialresolution of high speed (and typically high current) processes such asK-changes, return strokes and dart-leaders. In previous studies, we haveshown the usefulness of acoustic recordings to locate thunder sources aswell as infrasound pulses from <span class="hlt">lightning</span>. This work will present acomparison of Acoustic and Interferometric measurements from <span class="hlt">lightning</span>,using some interesting flashes, including a positive cloud to ground,that occurred in these campaigns.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950007857','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950007857"><span>Produce documents and media information. [on <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Alzmann, Melanie A.; Miller, G.A.</p> <p>1994-01-01</p> <p><span class="hlt">Lightning</span> data and information were collected from the United States, Germany, France, Brazil, China, and Australia for the dual purposes of compiling a global <span class="hlt">lightning</span> data base and producing publications on the Marshall Space Flight Center's <span class="hlt">lightning</span> program. Research covers the history of <span class="hlt">lightning</span>, the characteristics of a storm, types of lightningdischarges, observations from airplanes and spacecraft, the future fole of planes and spacecraft in <span class="hlt">lightning</span> studies, <span class="hlt">lightning</span> detection networks, and the relationships between <span class="hlt">lightning</span> and rainfall. Descriptions of the Optical Transient Dectector, the <span class="hlt">Lightning</span> Imaging Sensor, and the <span class="hlt">Lightning</span> Mapper Sensor are included.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006IJTFM.126...61K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006IJTFM.126...61K"><span><span class="hlt">Lightning</span> Phenomenology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kawasaki, Zen</p> <p></p> <p>This paper presents a phenomenological idea about <span class="hlt">lightning</span> flash to share the back ground understanding for this special issue. <span class="hlt">Lightning</span> discharges are one of the terrible phenomena, and Benjamin Franklin has led this natural phenomenon to the stage of scientific investigation. Technical aspects like monitoring and location are also summarized in this article.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-GRC-1945-C-08983.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-GRC-1945-C-08983.html"><span>Lockheed P–38J <span class="hlt">Lightning</span> at the Aircraft Engine Research <span class="hlt">Laboratory</span></span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>1945-03-21</p> <p>The National Advisory Committee for Aeronautics (NACA) Aircraft Engine Research <span class="hlt">Laboratory</span> acquired two Lockheed P–38J <span class="hlt">Lightning</span> in October 1944 to augment their burgeoning icing research program. The P–38 was a high-altitude interceptor with a unique twin fuselage configuration. Lockheed designed the aircraft in 1938 and 1939. Its two Allison V–1710 engines carried the aircraft to altitudes up to 40,000 feet. The P–38 was used extensively during World War II in a variety of roles. In August 1943, Lockheed began producing an improved version, the P–38J that included better cockpit heating, engine cooling, and dive flaps. The military loaned the NACA two P–38Js to determine the amount of ice formation on the induction system of the turbosupercharger-equipped engines. In 1944 and 1945 one of the aircraft was subjected to ground tests using an engine blower on the hangar apron. The V–1710 was run over a full range of speeds as different levels of water were injected into the blower and sprayed onto the engine. The other P–38J was flown at 10,000 feet altitude with water sprayed into the engine to simulate rain. The tests confirmed that closing the intercooler flap added protection against the ice by blocking water ingestion and increasing engine heat. NACA pilot Joseph Walker joined the Cleveland <span class="hlt">laboratory</span> in early 1945 as a physicist. Walker had flown P–38s during World, and later claimed that seeing the NACA’s two P–38Js inspired him to return to his earlier calling as a pilot, this time with the NACA. Walker was particularly active in the icing flight program during his five years of flying in Cleveland.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21570915-number-lightning-discharges-causing-damage-lightning-arrester-cables-aerial-transmission-lines-power-systems','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21570915-number-lightning-discharges-causing-damage-lightning-arrester-cables-aerial-transmission-lines-power-systems"><span>Number of <span class="hlt">lightning</span> discharges causing damage to <span class="hlt">lightning</span> arrester cables for aerial transmission lines in power systems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Nikiforov, E. P.</p> <p>2009-07-15</p> <p>Damage by <span class="hlt">lightning</span> discharges to <span class="hlt">lightning</span> arrester cables for 110-175 kV aerial transmission lines is analyzed using data from power systems on incidents with aerial transmission lines over a ten year operating period (1997-2006). It is found that failures of <span class="hlt">lightning</span> arrester cables occur when a tensile force acts on a cable heated to the melting point by a <span class="hlt">lightning</span> current. The <span class="hlt">lightning</span> currents required to heat a cable to this extent are greater for larger cable cross sections. The probability that a <span class="hlt">lightning</span> discharge will develop decreases as the amplitude of the <span class="hlt">lightning</span> current increases, which greatly reduces themore » number of <span class="hlt">lightning</span> discharges which damage TK-70 cables compared to TK-50 cables. In order to increase the reliability of <span class="hlt">lightning</span> arrester cables for 110 kV aerial transmission lines, TK-70 cables should be used in place of TK-50 cables. The number of <span class="hlt">lightning</span> discharges per year which damage <span class="hlt">lightning</span> arrester cables is lowered when the density of aerial transmission lines is reduced within the territory of electrical power systems. An approximate relationship between these two parameters is obtained.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29028438','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29028438"><span>Laser Sintering Technology and <span class="hlt">Balling</span> Phenomenon.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Oyar, Perihan</p> <p>2018-02-01</p> <p>The aim of this review was to evaluate the <span class="hlt">balling</span> phenomenon which occurs typically in Selective Laser Sintering (SLS). The <span class="hlt">balling</span> phenomenon is a typical SLS defect, and observed in laser sintered powder, significantly reduces the quality of SLS, and hinders the further development of SLS Technology. Electronic database searches were performed using Google Scholar. The keywords "laser sintering, selective laser sintering, direct metal laser melting, and <span class="hlt">balling</span> phenomenon" were searched in title/abstract of publications, limited to December 31, 2016. The inclusion criteria were SLS, <span class="hlt">balling</span> phenomenon, some alloys (such as Cr-Co, iron, stainless steel, and Cu-based alloys) mechanical properties, microstructure and bond strength between metal-ceramic crown, <span class="hlt">laboratory</span> studies, full text, and in English language. A total of 100 articles were found the initial search and yielded a total of 50 studies, 30 of which did not fulfill the inclusion criteria and were therefore excluded. In addition, 20 studies were found by screening the reference list of all included publications. Finally, 40 studies were selected for this review. The method in question is regulated by powder material characteristics and the conditions of laser processing. The procedure of formation, affecting factors, and the mechanism of the <span class="hlt">balling</span> effect are very complex.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27665937','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27665937"><span>Measuring Method for <span class="hlt">Lightning</span> Channel Temperature.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, X; Zhang, J; Chen, L; Xue, Q; Zhu, R</p> <p>2016-09-26</p> <p>In this paper, we demonstrate the temperature of <span class="hlt">lightning</span> channel utilizing the theory of <span class="hlt">lightning</span> spectra and the model of local thermodynamic equilibrium (LTE). The impulse current generator platform (ICGS) was used to simulate the <span class="hlt">lightning</span> discharge channel, and the spectral energy of infrared spectroscopy (930 nm) and the visible spectroscopy (648.2 nm) of the simulated <span class="hlt">lightning</span> has been calculated. Results indicate that the peaks of luminous intensity of both infrared and visible spectra increase with the <span class="hlt">lightning</span> current intensity in range of 5-50 kA. Based on the results, the temperature of the <span class="hlt">lightning</span> channel is derived to be 6140.8-10424 K. Moreover, the temperature of the channel is approximately exponential to the <span class="hlt">lightning</span> current intensity, which shows good agreement with that of the natural <span class="hlt">lightning</span> cases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...633906L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...633906L"><span>Measuring Method for <span class="hlt">Lightning</span> Channel Temperature</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, X.; Zhang, J.; Chen, L.; Xue, Q.; Zhu, R.</p> <p>2016-09-01</p> <p>In this paper, we demonstrate the temperature of <span class="hlt">lightning</span> channel utilizing the theory of <span class="hlt">lightning</span> spectra and the model of local thermodynamic equilibrium (LTE). The impulse current generator platform (ICGS) was used to simulate the <span class="hlt">lightning</span> discharge channel, and the spectral energy of infrared spectroscopy (930 nm) and the visible spectroscopy (648.2 nm) of the simulated <span class="hlt">lightning</span> has been calculated. Results indicate that the peaks of luminous intensity of both infrared and visible spectra increase with the <span class="hlt">lightning</span> current intensity in range of 5-50 kA. Based on the results, the temperature of the <span class="hlt">lightning</span> channel is derived to be 6140.8-10424 K. Moreover, the temperature of the channel is approximately exponential to the <span class="hlt">lightning</span> current intensity, which shows good agreement with that of the natural <span class="hlt">lightning</span> cases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023353','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023353"><span>Global <span class="hlt">lightning</span> studies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodman, Steven J.; Wright, Pat; Christian, Hugh; Blakeslee, Richard; Buechler, Dennis; Scharfen, Greg</p> <p>1991-01-01</p> <p>The global <span class="hlt">lightning</span> signatures were analyzed from the DMSP Optical Linescan System (OLS) imagery archived at the National Snow and Ice Data Center. Transition to analysis of the digital archive becomes available and compare annual, interannual, and seasonal variations with other global data sets. An initial survey of the quality of the existing film archive was completed and <span class="hlt">lightning</span> signatures were digitized for the summer months of 1986 to 1987. The relationship is studied between: (1) global and regional <span class="hlt">lightning</span> activity and rainfall, and (2) storm electrical development and environment. Remote sensing data sets obtained from field programs are used in conjunction with satellite/radar/<span class="hlt">lightning</span> data to develop and improve precipitation estimation algorithms, and to provide a better understanding of the co-evolving electrical, microphysical, and dynamical structure of storms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20030011406&hterms=Earth+fire&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DEarth%2Bfire','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20030011406&hterms=Earth+fire&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DEarth%2Bfire"><span>Great (Flame) <span class="hlt">Balls</span> of Fire! Structure of Flame <span class="hlt">Balls</span> at Low Lewis-number-2 (SOFBALL-2)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ronney, Paul; Weiland, Karen J.; Over, Ann (Technical Monitor)</p> <p>2002-01-01</p> <p>Everyone knows that an automobile engine wastes fuel and energy when it runs with a fuel-rich mixture. 'Lean' burning, mixing in more air and less fuel, is better for the environment. But lean mixtures also lead to engine misfiring and rough operation. No one knows the ultimate limits for lean operation, for 'weak' combustion that is friendly to the environment while still moving us around. This is where the accidental verification of a decades-old prediction may have strong implications for designing and running low-emissions engines in the 21st century. In 1944, Soviet physicist Yakov Zeldovich predicted that stationary, spherical flames are possible under limited conditions in lean fuel-air mixtures. Dr. Paul Ronney of the University of Southern California accidentally discovered such 'flame <span class="hlt">balls</span>' in experiments with lean hydrogen-air mixtures in 1984 during drop-tower experiments that provided just 2.2 seconds of near weightlessness. Experiments aboard NASA's low-g aircraft confirmed the results, but a thorough investigation was hampered by the aircraft's bumpy ride. And stable flame <span class="hlt">balls</span> can only exist in microgravity. The potential for investigating combustion at the limits of flammability, and the implications for spacecraft fire safety, led to the Structure of Flame <span class="hlt">Balls</span> at Low Lewis-number (SOFBALL) experiment flown twice aboard the Space Shuttle on the Microgravity Sciences <span class="hlt">Laboratory</span>-1 (MSL-1) in 1997. Success there led to the planned reflight on STS-107. Flame <span class="hlt">balls</span> are the weakest fires yet produced in space or on Earth. Typically each flame <span class="hlt">ball</span> produced only 1 watt of thermal power. By comparison, a birthday candle produces 50 watts. The Lewis-number measures the rate of diffusion of fuel into the flame <span class="hlt">ball</span> relative to the rate of diffusion of heat away from the flame <span class="hlt">ball</span>. Lewis-number mixtures conduct heat poorly. Hydrogen and methane are the only fuels that provide low enough Lewis-numbers to produce stable flame <span class="hlt">balls</span>, and even then only for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=The+AND+lightning&pg=2&id=EJ130237','ERIC'); return false;" href="https://eric.ed.gov/?q=The+AND+lightning&pg=2&id=EJ130237"><span>The <span class="hlt">Lightning</span> Discharge</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Orville, Richard E.</p> <p>1976-01-01</p> <p>Correspondence of Benjamin Franklin provides authenticity to a historical account of early work in the field of <span class="hlt">lightning</span>. Present-day theories concerning the formation and propagation of <span class="hlt">lightning</span> are expressed and photographic evidence provided. (CP)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2607583','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2607583"><span>Air traffic controller <span class="hlt">lightning</span> strike.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Spieth, M. E.; Kimura, R. L.; Schryer, T. D.</p> <p>1994-01-01</p> <p>Andersen Air Force Base in Guam boasts the tallest control tower in the Air Force. In 1986, an air traffic controller was struck by <span class="hlt">lightning</span> as the bolt proceeded through the tower. Although he received only a backache, the <span class="hlt">lightning</span> left a hole with surrounding scorch marks on his fatigue shirt and his undershirt. The <span class="hlt">lightning</span> strike also ignited a portion of the field lighting panel, which caused the runway lights to go out immediately. Lack of a <span class="hlt">lightning</span> rod is the most likely reason the controller was struck. Proper precautions against <span class="hlt">lightning</span> strikes can prevent such occupational safety hazards. PMID:7966436</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5036177','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5036177"><span>Measuring Method for <span class="hlt">Lightning</span> Channel Temperature</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Li, X.; Zhang, J.; Chen, L.; Xue, Q.; Zhu, R.</p> <p>2016-01-01</p> <p>In this paper, we demonstrate the temperature of <span class="hlt">lightning</span> channel utilizing the theory of <span class="hlt">lightning</span> spectra and the model of local thermodynamic equilibrium (LTE). The impulse current generator platform (ICGS) was used to simulate the <span class="hlt">lightning</span> discharge channel, and the spectral energy of infrared spectroscopy (930 nm) and the visible spectroscopy (648.2 nm) of the simulated <span class="hlt">lightning</span> has been calculated. Results indicate that the peaks of luminous intensity of both infrared and visible spectra increase with the <span class="hlt">lightning</span> current intensity in range of 5–50 kA. Based on the results, the temperature of the <span class="hlt">lightning</span> channel is derived to be 6140.8–10424 K. Moreover, the temperature of the channel is approximately exponential to the <span class="hlt">lightning</span> current intensity, which shows good agreement with that of the natural <span class="hlt">lightning</span> cases. PMID:27665937</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-PIA12575.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-PIA12575.html"><span>First <span class="hlt">Lightning</span> Flashes on Saturn</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2010-04-14</p> <p>NASA Cassini spacecraft captured the first <span class="hlt">lightning</span> flashes on Saturn. The storm that generated the <span class="hlt">lightning</span> lasted from January to October 2009, making it the longest-lasting <span class="hlt">lightning</span> storm known in the solar system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20180001922','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20180001922"><span>ENSO Related Interannual <span class="hlt">Lightning</span> Variability from the Full TRMM LIS <span class="hlt">Lightning</span> Climatology</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Clark, Austin; Cecil, Daniel J.</p> <p>2018-01-01</p> <p>It has been shown that the El Nino/Southern Oscillation (ENSO) contributes to inter-annual variability of <span class="hlt">lightning</span> production in the tropics and subtropics more than any other atmospheric oscillation. This study further investigated how ENSO phase affects <span class="hlt">lightning</span> production in the tropics and subtropics. Using the Tropical Rainfall Measuring Mission (TRMM) <span class="hlt">Lightning</span> Imaging Sensor (LIS) and the Oceanic Nino Index (ONI) for ENSO phase, <span class="hlt">lightning</span> data were averaged into corresponding mean annual warm, cold, and neutral 'years' for analysis of the different phases. An examination of the regional sensitivities and preliminary analysis of three locations was conducted using model reanalysis data to determine the leading convective mechanisms in these areas and how they might respond to the ENSO phases. These processes were then studied for inter-annual variance and subsequent correlation to ENSO during the study period to best describe the observed <span class="hlt">lightning</span> deviations from year to year at each location.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140003896','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140003896"><span>An Intrinsic Fiber-Optic Sensor for Structure <span class="hlt">Lightning</span> Current Measurement</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.; Mata, Carlos T.; Mata, Angel. G.; Snyder, Gary P.</p> <p>2014-01-01</p> <p>An intrinsic optical-fiber sensor based on Faraday Effect is developed that is highly suitable for measuring <span class="hlt">lightning</span> current on aircraft, towers and complex structures. Originally developed specifically for aircraft installations, it is light-weight, non-conducting, structure conforming, and is immune to electromagnetic interference, hysteresis and saturation. It can measure total current down to DC. When used on <span class="hlt">lightning</span> towers, the sensor can help validate other sensors and <span class="hlt">lightning</span> detection network measurements. Faraday Effect causes light polarization to rotate when the fiber is exposed to a magnetic field in the direction of light propagation. Thus, the magnetic field strength can be determined from the light polarization change. By forming closed fiber loops and applying Ampere's law, measuring the total light rotation yields the total current enclosed. A broadband, dual-detector, reflective polarimetric scheme allows measurement of both DC component and AC waveforms with a 60 dB dynamic range. Two systems were built that are similar in design but with slightly different sensitivities. The 1310nm laser system can measure 300 A - 300 kA, and has a 15m long sensing fiber. It was used in <span class="hlt">laboratory</span> testing, including measuring current on an aluminum structure simulating an aircraft fuselage or a <span class="hlt">lightning</span> tower. High current capabilities were demonstrated up to 200 kA at a <span class="hlt">lightning</span> test facility. The 1550nm laser system can measure 400 A - 400 kA and has a 25m fiber length. Used in field measurements, excellent results were achieved in the summer of 2012 measuring rocket-triggered <span class="hlt">lightning</span> at the International Center for <span class="hlt">Lightning</span> Research and Testing (ICLRT), Camp Blanding, Florida. In both systems increased sensitivity can be achieved with multiple fiber loops. The fiber optic sensor provides many unique capabilities not currently possible with traditional sensors. It represents an important new tool for <span class="hlt">lightning</span> current measurement where low weight</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21617740','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21617740"><span>Rad<span class="hlt">Ball</span> Technology Testing and MCNP Modeling of the Tungsten Collimator.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Farfán, Eduardo B; Foley, Trevor Q; Coleman, J Rusty; Jannik, G Timothy; Holmes, Christopher J; Oldham, Mark; Adamovics, John; Stanley, Steven J</p> <p>2010-01-01</p> <p>The United Kingdom's National Nuclear <span class="hlt">Laboratory</span> (NNL) has developed a remote, non-electrical, radiation-mapping device known as Rad<span class="hlt">Ball</span>(™), which can locate and quantify radioactive hazards within contaminated areas of the nuclear industry. Rad<span class="hlt">Ball</span>(™) consists of a colander-like outer shell that houses a radiation-sensitive polymer sphere. The outer shell works to collimate radiation sources and those areas of the polymer sphere that are exposed react, becoming increasingly more opaque, in proportion to the absorbed dose. The polymer sphere is imaged in an optical-CT scanner, which produces a high resolution 3D map of optical attenuation coefficients. Subsequent analysis of the optical attenuation matrix provides information on the spatial distribution of sources in a given area forming a 3D characterization of the area of interest. Rad<span class="hlt">Ball</span>(™) has no power requirements and can be positioned in tight or hard-to reach locations. The Rad<span class="hlt">Ball</span>(™) technology has been deployed in a number of technology trials in nuclear waste reprocessing plants at Sellafield in the United Kingdom and facilities of the Savannah River National <span class="hlt">Laboratory</span> (SRNL). This study focuses on the Rad<span class="hlt">Ball</span>(™) testing and modeling accomplished at SRNL.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19790010065','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790010065"><span>Space Shuttle <span class="hlt">Lightning</span> Protection</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Suiter, D. L.; Gadbois, R. D.; Blount, R. L.</p> <p>1979-01-01</p> <p>The technology for <span class="hlt">lightning</span> protection of even the most advanced spacecraft is available and can be applied through cost-effective hardware designs and design-verification techniques. In this paper, the evolution of the Space Shuttle <span class="hlt">Lightning</span> Protection Program is discussed, including the general types of protection, testing, and anlayses being performed to assess the <span class="hlt">lightning</span>-transient-damage susceptibility of solid-state electronics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title14-vol1/pdf/CFR-2011-title14-vol1-sec25-581.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title14-vol1/pdf/CFR-2011-title14-vol1-sec25-581.pdf"><span>14 CFR 25.581 - <span class="hlt">Lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-01-01</p> <p>... STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure <span class="hlt">Lightning</span> Protection § 25.581 <span class="hlt">Lightning</span> protection. (a) The airplane must be protected against catastrophic effects from <span class="hlt">lightning</span>. (b) For metallic... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false <span class="hlt">Lightning</span> protection. 25.581 Section 25.581...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title14-vol1/pdf/CFR-2014-title14-vol1-sec25-581.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title14-vol1/pdf/CFR-2014-title14-vol1-sec25-581.pdf"><span>14 CFR 25.581 - <span class="hlt">Lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-01-01</p> <p>... STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure <span class="hlt">Lightning</span> Protection § 25.581 <span class="hlt">Lightning</span> protection. (a) The airplane must be protected against catastrophic effects from <span class="hlt">lightning</span>. (b) For metallic... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false <span class="hlt">Lightning</span> protection. 25.581 Section 25.581...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title14-vol1/pdf/CFR-2013-title14-vol1-sec25-581.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title14-vol1/pdf/CFR-2013-title14-vol1-sec25-581.pdf"><span>14 CFR 25.581 - <span class="hlt">Lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-01-01</p> <p>... STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure <span class="hlt">Lightning</span> Protection § 25.581 <span class="hlt">Lightning</span> protection. (a) The airplane must be protected against catastrophic effects from <span class="hlt">lightning</span>. (b) For metallic... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false <span class="hlt">Lightning</span> protection. 25.581 Section 25.581...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title14-vol1/pdf/CFR-2012-title14-vol1-sec25-581.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title14-vol1/pdf/CFR-2012-title14-vol1-sec25-581.pdf"><span>14 CFR 25.581 - <span class="hlt">Lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-01-01</p> <p>... STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure <span class="hlt">Lightning</span> Protection § 25.581 <span class="hlt">Lightning</span> protection. (a) The airplane must be protected against catastrophic effects from <span class="hlt">lightning</span>. (b) For metallic... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false <span class="hlt">Lightning</span> protection. 25.581 Section 25.581...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130014258','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130014258"><span><span class="hlt">Lightning</span> NOx Statistics Derived by NASA <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) Data Analyses</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William; Peterson, Harold</p> <p>2013-01-01</p> <p>What is the LNOM? The NASA Marshall Space Flight Center (MSFC) <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) [Koshak et al., 2009, 2010, 2011; Koshak and Peterson 2011, 2013] analyzes VHF <span class="hlt">Lightning</span> Mapping Array (LMA) and National <span class="hlt">Lightning</span> Detection Network(TradeMark) (NLDN) data to estimate the <span class="hlt">lightning</span> nitrogen oxides (LNOx) produced by individual flashes. Figure 1 provides an overview of LNOM functionality. Benefits of LNOM: (1) Does away with unrealistic "vertical stick" <span class="hlt">lightning</span> channel models for estimating LNOx; (2) Uses ground-based VHF data that maps out the true channel in space and time to < 100 m accuracy; (3) Therefore, true channel segment height (ambient air density) is used to compute LNOx; (4) True channel length is used! (typically tens of kilometers since channel has many branches and "wiggles"); (5) Distinction between ground and cloud flashes are made; (6) For ground flashes, actual peak current from NLDN used to compute NOx from <span class="hlt">lightning</span> return stroke; (7) NOx computed for several other <span class="hlt">lightning</span> discharge processes (based on Cooray et al., 2009 theory): (a) Hot core of stepped leaders and dart leaders, (b) Corona sheath of stepped leader, (c) K-change, (d) Continuing Currents, and (e) M-components; and (8) LNOM statistics (see later) can be used to parameterize LNOx production for regional air quality models (like CMAQ), and for global chemical transport models (like GEOS-Chem).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820000305&hterms=thunderstorm+protection&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dthunderstorm%2Bprotection','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820000305&hterms=thunderstorm+protection&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dthunderstorm%2Bprotection"><span>The Design of <span class="hlt">Lightning</span> Protection</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1983-01-01</p> <p>Engineering study guides design and monitoring of <span class="hlt">lightning</span> protection. Design studies for project are collected in 150-page report, containing wealth of information on design of <span class="hlt">lightning</span> protection systems and on instrumentation for monitoring current waveforms of <span class="hlt">lightning</span> strokes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EOSTr..91...57S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EOSTr..91...57S"><span>Effects of <span class="hlt">Lightning</span> in the Upper Atmosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sentman, Davis D.; Pasko, Victor P.; Morrill, Jeff S.</p> <p>2010-02-01</p> <p>AGU Chapman Conference on Effects of Thunderstorms and <span class="hlt">Lightning</span> in the Upper Atmosphere; University Park, Pennsylvania, 10-14 May 2009; The serendipitous observation in 1989 of electrical discharge in the high atmosphere induced by thundercloud <span class="hlt">lightning</span> launched a new field of geophysical investigation. From this single unexpected observation sprang a vigorous and fertile new research field that simultaneously encompasses geophysical disciplines that are normally pursued independently, such as meteorology and <span class="hlt">lightning</span>, plasma and gas discharge physics, atmospheric chemistry, ionospheric physics, and energetic particle physics. Transient electrical discharge in the upper atmosphere spans the full range of altitudes between the tropopause and the ionosphere and takes a variety of forms that carry the whimsical names red sprites, blue jets, gigantic jets, elves (emissions of light and very low frequency perturbations from electromagnetic pulse sources), and sprite halos, collectively known as transient luminous events (TLEs). To date, TLEs have been observed from ground and airborne or spaceborne platforms above thunderstorm systems worldwide, and radio observations made concomitantly with optical observations have shown that they are produced by the transient far fields of thundercloud <span class="hlt">lightning</span>. TLEs appear to be large-scale (tens of kilometers in dimension), upper atmospheric versions of conventional gas discharge akin to weakly ionized, collision-dominated systems found in <span class="hlt">laboratory</span> discharge devices (millimeter-centimeter dimensions), with characteristic energies of a few electron volts. The dominant physical processes have been identified as described by the familiar kinetic theory of the photochemistry of the upper atmosphere, but with electric field-driven electron impact ionization playing the role of photolysis or energetic precipitating particle-induced ionization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19820019046','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19820019046"><span>Correlation of satellite <span class="hlt">lightning</span> observations with ground-based <span class="hlt">lightning</span> experiments in Florida, Texas and Oklahoma</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Edgar, B. C.; Turman, B. N.</p> <p>1982-01-01</p> <p>Satellite observations of <span class="hlt">lightning</span> were correlated with ground-based measurements of <span class="hlt">lightning</span> from data bases obtained at three separate sites. The percentage of ground-based observations of <span class="hlt">lightning</span> that would be seen by an orbiting satellite was determined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA614923','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA614923"><span>Utilizing Four Dimensional <span class="hlt">Lightning</span> and Dual-Polarization Radar to Develop <span class="hlt">Lightning</span> Initiation Forecast Guidance</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2015-03-26</p> <p>Electrification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.3 <span class="hlt">Lightning</span> Discharge ...charge is caused by falling graupel that is positively charged (Wallace and Hobbs 2006). 2.3 <span class="hlt">Lightning</span> Discharge <span class="hlt">Lightning</span> occurs when the electric...emission of positive corona from the surface of precipitation particles, causing the electric field to become locally enhanced and supporting the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013GeoJI.195..117S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013GeoJI.195..117S"><span><span class="hlt">Lightning</span>-induced remanent magnetization—the Vredefort impact structure, South Africa</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Salminen, Johanna; Pesonen, Lauri J.; Lahti, Kari; Kannus, Kari</p> <p>2013-10-01</p> <p>Earlier studies at the large Vredefort impact structure since 1960 have shown that values of natural remanent magnetizations (NRMs) and, hence, Koenigsberger's Q values (ratio of remanent over induced magnetization), for different rock lithologies are elevated compared to the values for similar rock types around the world. Three origins for the high Q values have been suggested, namely shock by meteorite impact, enhanced plasma field and <span class="hlt">lightning</span> strikes. We have studied whether <span class="hlt">laboratory</span> <span class="hlt">lightning</span> experiments can produce enhanced NRMs in the Vredefort target rocks. For comparison, we also included rocks from the Johannesburg dome, which is not a meteorite impact site. The results revealed increased NRMs, susceptibility and Q values of the rocks from both Vredefort and Johannesburg domes. Rock magnetic measurements and scanning electron microscope analyses of <span class="hlt">lightning</span> pulsed and unpulsed samples showed that the <span class="hlt">lightning</span> included changes in magnetic properties of the rocks. We suggest that in some samples <span class="hlt">lightning</span> have changed magnetic mineralogy by oxidizing magnetite to maghemite. Indication of this oxidation came from the low-temperature variation of the remanent magnetization where we observed several hallmarks of maghemitization in samples treated by <span class="hlt">lightning</span> strikes. Further indications of mineralogical changes include increased Curie points above the magnetite's Curie point (580 °C) and appearance of pronounced lower temperature (200-400 °C) phases in susceptibility versus temperature curves. These changes are interpreted to indicate partially oxidized magnetite (maghemitization) coupled with grain fragmentations and by this way grain size reduction. High-temperature hysteresis and REM (= NRM/saturation isothermal remanent magnetization) studies support these conclusions. Our results were analogous with the ones for lodestones and protolodestones where partially oxidized magnetite is thought to make magnetization more intense.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990009077','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990009077"><span><span class="hlt">Lightning</span> Characteristics and <span class="hlt">Lightning</span> Strike Peak Current Probabilities as Related to Aerospace Vehicle Operations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Johnson, Dale L.; Vaughan, William W.</p> <p>1998-01-01</p> <p>A summary is presented of basic <span class="hlt">lightning</span> characteristics/criteria for current and future NASA aerospace vehicles. The paper estimates the probability of occurrence of a 200 kA peak <span class="hlt">lightning</span> return current, should <span class="hlt">lightning</span> strike an aerospace vehicle in various operational phases, i.e., roll-out, on-pad, launch, reenter/land, and return-to-launch site. A literature search was conducted for previous work concerning occurrence and measurement of peak lighting currents, modeling, and estimating probabilities of launch vehicles/objects being struck by <span class="hlt">lightning</span>. This paper presents these results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20180001961','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20180001961"><span>ENSO Related Inter-Annual <span class="hlt">Lightning</span> Variability from the Full TRMM LIS <span class="hlt">Lightning</span> Climatology</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Clark, Austin; Cecil, Daniel</p> <p>2018-01-01</p> <p>The El Nino/Southern Oscillation (ENSO) contributes to inter-annual variability of <span class="hlt">lightning</span> production more than any other atmospheric oscillation. This study further investigated how ENSO phase affects <span class="hlt">lightning</span> production in the tropics and subtropics using the Tropical Rainfall Measuring Mission (TRMM) <span class="hlt">Lightning</span> Imaging Sensor (LIS). <span class="hlt">Lightning</span> data were averaged into mean annual warm, cold, and neutral 'years' for analysis of the different phases and compared to model reanalysis data. An examination of the regional sensitivities and preliminary analysis of three locations was conducted using model reanalysis data to determine the leading convective mechanisms in these areas and how they might respond to the ENSO phases</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20090037586','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20090037586"><span>NASA Manned Launch Vehicle <span class="hlt">Lightning</span> Protection Development</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>McCollum, Matthew B.; Jones, Steven R.; Mack, Jonathan D.</p> <p>2009-01-01</p> <p>Historically, the National Aeronautics and Space Administration (NASA) relied heavily on <span class="hlt">lightning</span> avoidance to protect launch vehicles and crew from <span class="hlt">lightning</span> effects. As NASA transitions from the Space Shuttle to the new Constellation family of launch vehicles and spacecraft, NASA engineers are imposing design and construction standards on the spacecraft and launch vehicles to withstand both the direct and indirect effects of <span class="hlt">lightning</span>. A review of current Space Shuttle <span class="hlt">lightning</span> constraints and protection methodology will be presented, as well as a historical review of Space Shuttle <span class="hlt">lightning</span> requirements and design. The Space Shuttle <span class="hlt">lightning</span> requirements document, NSTS 07636, <span class="hlt">Lightning</span> Protection, Test and Analysis Requirements, (originally published as document number JSC 07636, <span class="hlt">Lightning</span> Protection Criteria Document) was developed in response to the Apollo 12 <span class="hlt">lightning</span> event and other experiences with NASA and the Department of Defense launch vehicles. This document defined the <span class="hlt">lightning</span> environment, vehicle protection requirements, and design guidelines for meeting the requirements. The criteria developed in JSC 07636 were a precursor to the Society of Automotive Engineers (SAE) <span class="hlt">lightning</span> standards. These SAE standards, along with Radio Technical Commission for Aeronautics (RTCA) DO-160, Environmental Conditions and Test Procedures for Airborne Equipment, are the basis for the current Constellation <span class="hlt">lightning</span> design requirements. The development and derivation of these requirements will be presented. As budget and schedule constraints hampered <span class="hlt">lightning</span> protection design and verification efforts, the Space Shuttle elements waived the design requirements and relied on <span class="hlt">lightning</span> avoidance in the form of launch commit criteria (LCC) constraints and a catenary wire system for <span class="hlt">lightning</span> protection at the launch pads. A better understanding of the <span class="hlt">lightning</span> environment has highlighted the vulnerability of the protection schemes and associated risk to the vehicle</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMAE12A..05A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMAE12A..05A"><span>Where are the <span class="hlt">lightning</span> hotspots on Earth?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Albrecht, R. I.; Goodman, S. J.; Buechler, D. E.; Blakeslee, R. J.; Christian, H. J., Jr.</p> <p>2015-12-01</p> <p>The first <span class="hlt">lightning</span> observations from space date from the early 1960s and more than a dozen spacecraft orbiting the Earth have flown instruments that recorded <span class="hlt">lightning</span> signals from thunderstorms over the past 45 years. In this respect, the Tropical Rainfall Measuring Mission (TRMM) <span class="hlt">Lightning</span> Imaging Sensor (LIS), having just completed its mission (1997-2015), provides the longest and best total (intracloud and cloud-to-ground) <span class="hlt">lightning</span> data base over the tropics.We present a 16 year (1998-2013) reprocessed data set to create very high resolution (0.1°) TRMM LIS total <span class="hlt">lightning</span> climatology. This detailed very high resolution climatology is used to identify the Earth's <span class="hlt">lightning</span> hotspots and other regional features. Earlier studies located the <span class="hlt">lightning</span> hotspot within the Congo Basin in Africa, but our very high resolution <span class="hlt">lightning</span> climatology found that the highest <span class="hlt">lightning</span> flash rate on Earth actually occurs in Venezuela over Lake Maracaibo, with a distinct maximum during the night. The higher resolution dataset clearly shows that similar phenomenon also occurs over other inland lakes with similar conditions, i.e., locally forced convergent flow over a warm lake surface which drives deep nocturnal convection. Although Africa does not have the top <span class="hlt">lightning</span> hotspot, it comes in a close second and it is the continent with the highest number of <span class="hlt">lightning</span> hotspots, followed by Asia, South America, North America, and Oceania. We also present climatological maps for local hour and month of <span class="hlt">lightning</span> maxima, along with a ranking of the highest five hundred <span class="hlt">lightning</span> maxima, focusing discussion on each continent's 10 highest <span class="hlt">lightning</span> maxima. Most of the highest continental maxima are located near major mountain ranges, revealing the importance of local topography in thunderstorm development. These results are especially relevant in anticipation of the upcoming availability of continuous total <span class="hlt">lightning</span> observations from the Geostationary <span class="hlt">Lightning</span> Mapping (GLM</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29073666','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29073666"><span>Trigeminal Neuralgia Following <span class="hlt">Lightning</span> Injury.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>López Chiriboga, Alfonso S; Cheshire, William P</p> <p>2017-01-01</p> <p><span class="hlt">Lightning</span> and other electrical incidents are responsible for more than 300 injuries and 100 deaths per year in the United States alone. <span class="hlt">Lightning</span> strikes can cause a wide spectrum of neurologic manifestations affecting any part of the neuraxis through direct strikes, side flashes, touch voltage, connecting leaders, or acoustic shock waves. This article describes the first case of trigeminal neuralgia induced by <span class="hlt">lightning</span> injury to the trigeminal nerve, thereby adding a new syndrome to the list of possible <span class="hlt">lightning</span>-mediated neurologic injuries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20817399','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20817399"><span>Industrial accidents triggered by <span class="hlt">lightning</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Renni, Elisabetta; Krausmann, Elisabeth; Cozzani, Valerio</p> <p>2010-12-15</p> <p>Natural disasters can cause major accidents in chemical facilities where they can lead to the release of hazardous materials which in turn can result in fires, explosions or toxic dispersion. <span class="hlt">Lightning</span> strikes are the most frequent cause of major accidents triggered by natural events. In order to contribute towards the development of a quantitative approach for assessing <span class="hlt">lightning</span> risk at industrial facilities, <span class="hlt">lightning</span>-triggered accident case histories were retrieved from the major industrial accident databases and analysed to extract information on types of vulnerable equipment, failure dynamics and damage states, as well as on the final consequences of the event. The most vulnerable category of equipment is storage tanks. <span class="hlt">Lightning</span> damage is incurred by immediate ignition, electrical and electronic systems failure or structural damage with subsequent release. Toxic releases and tank fires tend to be the most common scenarios associated with <span class="hlt">lightning</span> strikes. Oil, diesel and gasoline are the substances most frequently released during <span class="hlt">lightning</span>-triggered Natech accidents. Copyright © 2010 Elsevier B.V. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1983RvGSP..21..892W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1983RvGSP..21..892W"><span>Planetary <span class="hlt">lightning</span> - Earth, Jupiter, and Venus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Williams, M. A.; Krider, E. P.; Hunten, D. M.</p> <p>1983-05-01</p> <p>The principal characteristics of <span class="hlt">lightning</span> on earth are reviewed, and the evidence for <span class="hlt">lightning</span> on Venus and Jupiter is examined. The mechanisms believed to be important to the electrification of terrestrial clouds are reviewed, with attention given to the applicability of some of these mechanisms to the atmospheres of Venus and Jupiter. The consequences of the existence of <span class="hlt">lightning</span> on Venus and Jupiter for their atmospheres and for theories of cloud electrification on earth are also considered. Since spacecraft observations do not conclusively show that <span class="hlt">lightning</span> does occur on Venus, it is suggested that alternative explanations for the experimental results be explored. Since Jupiter has no true surface, the Jovian <span class="hlt">lightning</span> flashes are cloud dischargaes. Observations suggest that Jovian <span class="hlt">lightning</span> emits, on average, 10 to the 10 J of optical energy per flash, whereas on earth <span class="hlt">lightning</span> radiates only about 10 to the 6th J per flash. Estimates of the average planetary <span class="hlt">lightning</span> rate on Jupiter range from 0.003 per sq km per yr to 40 per sq km per yr.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMAE41A..06S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE41A..06S"><span>Combining GOES-16 Geostationary <span class="hlt">Lightning</span> Mapper with the ground based Earth Networks Total <span class="hlt">Lightning</span> Network</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stock, M.; Lapierre, J. L.; Zhu, Y.</p> <p>2017-12-01</p> <p>Recently, the Geostationary <span class="hlt">Lightning</span> Mapper (GLM) began collecting optical data to locate <span class="hlt">lightning</span> events and flashes over the North and South American continents. This new instrument promises uniformly high detection efficiency (DE) over its entire field of view, with location accuracy on the order of 10 km. In comparison, Earth Networks Total <span class="hlt">Lightning</span> Networks (ENTLN) has a less uniform coverage, with higher DE in regions with dense sensor coverage, and lower DE with sparse sensor coverage. ENTLN also offers better location accuracy, <span class="hlt">lightning</span> classification, and peak current estimation for their <span class="hlt">lightning</span> locations. It is desirable to produce an integrated dataset, combining the strong points of GLM and ENTLN. The easiest way to achieve this is to simply match located <span class="hlt">lightning</span> processes from each system using time and distance criteria. This simple method will be limited in scope by the uneven coverage of the ground based network. Instead, we will use GLM group locations to look up the electric field change data recorded by ground sensors near each GLM group, vastly increasing the coverage of the ground network. The ground waveforms can then be used for: improvements to differentiation between glint and <span class="hlt">lightning</span> for GLM, higher precision lighting location, current estimation, and <span class="hlt">lightning</span> process classification. Presented is an initial implementation of this type of integration using preliminary GLM data, and waveforms from ENTLN.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920000497&hterms=faraday&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dfaraday','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920000497&hterms=faraday&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dfaraday"><span>Faraday Cage Protects Against <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jafferis, W.; Hasbrouck, R. T.; Johnson, J. P.</p> <p>1992-01-01</p> <p>Faraday cage protects electronic and electronically actuated equipment from <span class="hlt">lightning</span>. Follows standard <span class="hlt">lightning</span>-protection principles. Whether <span class="hlt">lightning</span> strikes cage or cables running to equipment, current canceled or minimized in equipment and discharged into ground. Applicable to protection of scientific instruments, computers, radio transmitters and receivers, and power-switching equipment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70045428','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70045428"><span><span class="hlt">Ball</span> clay</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Virta, R.L.</p> <p>2001-01-01</p> <p>Part of the 2000 annual review of the industrial minerals sector. A general overview of the <span class="hlt">ball</span> clay industry is provided. In 2000, sales of <span class="hlt">ball</span> clay reached record levels, with sanitary ware and tile applications accounting for the largest sales. <span class="hlt">Ball</span> clay production, consumption, prices, foreign trade, and industry news are summarized. The outlook for the <span class="hlt">ball</span> clay industry is also outlined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850008037&hterms=cookbook&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcookbook','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850008037&hterms=cookbook&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcookbook"><span><span class="hlt">Lightning</span> research: A user's lament</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Golub, C. N.</p> <p>1984-01-01</p> <p>As a user of devices and procedures for <span class="hlt">lightning</span> protection, the author is asking the <span class="hlt">lightning</span> research community for cookbook recipes to help him solve his problems. He is lamenting that realistic devices are scarce and that his mission does not allow him the time nor the wherewithal to bridge the gap between research and applications. A few case histories are presented. In return for their help he is offering researchers a key to <span class="hlt">lightning</span> technology--the use of the Eastern Test Range and its extensive resources as a proving ground for their experiment in the <span class="hlt">lightning</span> capital of the United States. A current example is given--a joint <span class="hlt">lightning</span> characterization project to take place there. Typical resources are listed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21143289-approach-lightning-overvoltage-protection-medium-voltage-lines-severe-lightning-areas','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21143289-approach-lightning-overvoltage-protection-medium-voltage-lines-severe-lightning-areas"><span>An Approach to the <span class="hlt">Lightning</span> Overvoltage Protection of Medium Voltage Lines in Severe <span class="hlt">Lightning</span> Areas</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Omidiora, M. A.; Lehtonen, M.</p> <p>2008-05-08</p> <p>This paper deals with the effect of shield wires on <span class="hlt">lightning</span> overvoltage reduction and the energy relief of MOV (Metal Oxide Varistor) arresters from direct strokes to distribution lines. The subject of discussion is the enhancement of <span class="hlt">lightning</span> protection in Finnish distribution networks where <span class="hlt">lightning</span> is most severe. The true index of <span class="hlt">lightning</span> severity in these areas is based on the ground flash densities and return stroke data collected from the Finnish meteorological institute. The presented test case is the IEEE 34-node test feeder injected with multiple <span class="hlt">lightning</span> strokes and simulated with the Alternative Transients Program/Electromagnetic Transients program (ATP/EMTP). Themore » response of the distribution line to <span class="hlt">lightning</span> strokes was modeled with three different cases: no protection, protection with surge arresters and protection with a combination of shield wire and arresters. Simulations were made to compare the resulting overvoltages on the line for all the analyzed cases.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMAE31A0267Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMAE31A0267Z"><span>Statistical Patterns in Natural <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zoghzoghy, F. G.; Cohen, M.; Said, R.; Inan, U. S.</p> <p>2011-12-01</p> <p>Every day millions of <span class="hlt">lightning</span> flashes occur around the globe but the understanding of this natural phenomenon is still lacking. Fundamentally, <span class="hlt">lightning</span> is nature's way of destroying charge separation in clouds and restoring electric neutrality. Thus, statistical patterns of <span class="hlt">lightning</span> activity indicate the scope of these electric discharges and offer a surrogate measure of timescales for charge buildup in thunderclouds. We present a statistical method to investigate spatio-temporal correlations among <span class="hlt">lightning</span> flashes using National <span class="hlt">Lightning</span> Detection Network (NLDN) stroke data. By monitoring the distribution of <span class="hlt">lightning</span> activity, we can observe the charging and discharging processes in a given thunderstorm. In particular, within a given storm, the flashes do not occur as a memoryless random process. We introduce the No Flash Zone (NFZ) which results from the suppressed probability of two consecutive neighboring flashes. This effect lasts for tens of seconds and can extend up to 15 km around the location of the initial flash, decaying with time. This suppression effect may be a function of variables such as storm location, storm phase, and stroke peak current. We develop a clustering algorithm, Storm-Locator, which groups strokes into flashes, storm cells, and thunderstorms, and enables us to study <span class="hlt">lightning</span> and the NFZ in different geographical regions, and for different storms. The recursive algorithm also helps monitor the interaction among spatially displaced storm cells, and can provide more insight into the spatial and temporal impacts of <span class="hlt">lightning</span> discharges.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFMHG31A..02A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFMHG31A..02A"><span>The Power of the Point: Benjamin Franklin, the <span class="hlt">Lightning</span> Rod and Two Misconceptions That Have Plagued Us to This Day</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aulich, G. D.; Moore, C. B.; Rison, W.</p> <p>2006-12-01</p> <p>Most people know that Ben Franklin invented the <span class="hlt">lightning</span> rod and that his rods have successfully protected structures for over 250 years. What people don't know is that he invented them on the basis of two misconceptions. The first, that an elevated pointed conductor would discharge a thunderstorm, thereby preventing <span class="hlt">lightning</span>. The second, that, should the first process fail, the elevated conductor, by virtue of its pointed tip, would serve as a preferred receptor for any <span class="hlt">lightning</span> strokes that did occur. It has long been known that grounded, elevated, pointed conductors can not discharge thunderstorms and experiments conducted at the Langmuir <span class="hlt">Laboratory</span> during the 1990s have shown that moderately blunt, rather than pointed, rods are the best receptors for <span class="hlt">lightning</span> strokes. Nevertheless, Franklin's incorrect ideas about <span class="hlt">lightning</span> rods persist in many minds, even among some people in the <span class="hlt">lightning</span> protection business.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800013441','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800013441"><span><span class="hlt">Lightning</span> Technology: Proceedings of a Technical Symposium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1980-01-01</p> <p>Several facets of <span class="hlt">lightning</span> technology are considered including phenomenology, measurement, detection, protection, interaction, and testing. <span class="hlt">Lightning</span> electromagnetics, protection of ground systems, and simulated <span class="hlt">lightning</span> testing are emphasized. The <span class="hlt">lightning</span>-instrumented F-106 aircraft is described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1805e0002S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1805e0002S"><span>Kinetic study of ferronickel slag grinding at variation of <span class="hlt">ball</span> filling and ratio of feed to grinding <span class="hlt">balls</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sanwani, Edy; Ikhwanto, Muhammad</p> <p>2017-01-01</p> <p>The objective of this paper is to investigate the effect of <span class="hlt">ball</span> filling and ratio of feed to grinding <span class="hlt">balls</span> on the kinetic of grinding of ferronickel slag in a <span class="hlt">laboratory</span> scale <span class="hlt">ball</span> mill. The experiments were started by crushing the ferronickel slag samples using a roll crusher to produce -3 mesh (-6.7 mm) product. This product, after sampling and sample dividing processes, was then used as feed for grinding process. The grinding was performed with variations of <span class="hlt">ball</span> filling and ratio of feed to grinding <span class="hlt">balls</span> for 150 minutes. At every certain time interval, particle size analysis was carried out on the grinding product. The results of the experiments were also used to develop linear regression model of the effect of grinding variables on the P80 of the product. Based on this study, it was shown that P80 values of the grinding products declined sharply until 70 minutes of grinding time due to the dominant mechanism of impact breakage and then decreased slowly after 70 minutes until 150 minutes of grinding time due to dominant mechanism of attrition breakage. Kinetics study of the grinding process on variations of grinding <span class="hlt">ball</span> filling showed that the optimum rate of formation of fine particles for 20%, 30%, 40% and 50% mill volume was achieved at a particle size of 400 µm in which the best initial rate of formation occurred at 50% volume of mill. At the variations of ratio of feed to grinding <span class="hlt">balls</span> it was shown that the optimum rate of grinding for the ratio of 1:10, 1: 8 and 1: 6 was achieved at a particle size of 400 µm and for the ratio of 1: 4 was at 841 µm in which the best initial rate of formation occurred at a 1:10 ratio. In this study, it was also produced two regression models that can predict the P80 value of the grinding product as a function of the variables of grinding time, <span class="hlt">ball</span> filling and the ratio of the feed to grinding <span class="hlt">balls</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/7236988-lightning-protection-distribution-lines','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/7236988-lightning-protection-distribution-lines"><span><span class="hlt">Lightning</span> protection of distribution lines</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>McDermott, T.E.; Short, T.A.; Anderson, J.G.</p> <p>1994-01-01</p> <p>This paper reports a study of distribution line <span class="hlt">lightning</span> performance, using computer simulations of <span class="hlt">lightning</span> overvoltages. The results of previous investigations are extended with a detailed model of induced voltages from nearby strokes, coupled into a realistic power system model. The paper also considers the energy duty of distribution-class surge arresters exposed to direct strokes. The principal result is that widely separated pole-top arresters can effectively protect a distribution line from induced-voltage flashovers. This means that nearby <span class="hlt">lightning</span> strokes need not be a significant <span class="hlt">lightning</span> performance problem for most distribution lines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19790006134','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790006134"><span><span class="hlt">Lightning</span> current detector</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Livermore, S. F. (Inventor)</p> <p>1978-01-01</p> <p>An apparatus for measuring the intensity of current produced in an elongated electrical conductive member by a <span class="hlt">lightning</span> strike for determining the intensity of the <span class="hlt">lightning</span> strike is presented. The apparatus includes an elongated strip of magnetic material that is carried within an elongated tubular housing. A predetermined electrical signal is recorded along the length of said elongated strip of magnetic material. One end of the magnetic material is positioned closely adjacent to the electrically conductive member so that the magnetic field produced by current flowing through said electrically conductive member disturbs a portion of the recorded electrical signal directly proportional to the intensity of the <span class="hlt">lightning</span> strike.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=The+AND+lightning&pg=2&id=EJ610411','ERIC'); return false;" href="https://eric.ed.gov/?q=The+AND+lightning&pg=2&id=EJ610411"><span>Updated <span class="hlt">Lightning</span> Safety Recommendations.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Vavrek, R. James; Holle, Ronald L.; Lopez, Raul E.</p> <p>1999-01-01</p> <p>Summarizes the recommendations of the <span class="hlt">Lightning</span> Safety Group (LSG), which was first convened during the 1998 American Meteorological Society Conference. Findings outline appropriate actions under various circumstances when <span class="hlt">lightning</span> threatens. (WRM)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMAE33A2530H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE33A2530H"><span>Characteristics of the <span class="hlt">Lightning</span> Activities in Southwest China from Low-Earth Orbiting and Geostationary Satellites-, and Ground-based <span class="hlt">Lightning</span> Observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hui, W.; Huang, F.; Guo, Q.; Li, D.; Yao, Z.; Zou, W.</p> <p>2017-12-01</p> <p>The development of <span class="hlt">lightning</span> detection technology accumulates a large amount of long-term data for investigating the <span class="hlt">lightning</span> activities. Ground-based <span class="hlt">lightning</span> networks provide continuous <span class="hlt">lightning</span> location but offer limited spatial coverage because of the complex underlying surface conditions. Space-based optical sensors can detect <span class="hlt">lightning</span> with global homogeneity. However, observing from satellites in low-earth orbit has fixed locations at the ground very shortly during its overpasses. The latest launched geostationary satellite-based <span class="hlt">lightning</span> imagers can detect <span class="hlt">lightning</span> in real time, and provide complete life-cycle coverage of each observed thunderstorm. In this study, based on multi-source <span class="hlt">lightning</span> data, the <span class="hlt">lightning</span> activities in southwest China, which with complex terrain and prone to appear <span class="hlt">lightning</span>, are researched. Firstly, the climatological characteristics of <span class="hlt">lightning</span> activities in this region from 1998 to 2013 are analyzed by using very-high resolution (0.1°) <span class="hlt">Lightning</span> Imaging Sensor (LIS)-derived data. The results indicate that the <span class="hlt">lightning</span> activity is more intense in eastern and southern regions of southwest China than in western and northern regions; the monthly and hourly flash densities also show its obvious seasonal and diurnal variation respectively, which is consistent with the development of the convective systems in the region. The results show that the spatial and temporal distribution of <span class="hlt">lightning</span> activities in southwest China is related to its topography, water vapor, and atmospheric conditions. Meanwhile, by comparing with the analysis derived data from Chinese Ground-based <span class="hlt">Lightning</span> Location System, the LIS-based detection results are confirmed. Furthermore, the process of a thunderstorm in southwest China from 29 to 30 March 2017 is investigated by using the new-generation monitoring data of Chinese Fengyun-4 geostationary satellite-based <span class="hlt">Lightning</span> Mapping Imager (LMI) and the rainfall data. The results tell us more about the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023400','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023400"><span><span class="hlt">Lightning</span> testing at the subsystem level</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Luteran, Frank</p> <p>1991-01-01</p> <p>Testing at the subsystem or black box level for <span class="hlt">lightning</span> hardness is required if system hardness is to be assured at the system level. The often applied philosophy of lighting testing only at the system level leads to extensive end of the line design changes which result in excessive costs and time delays. In order to perform testing at the subsystem level two important factors must be defined to make the testing simulation meaningful. The first factor is the definition of the test stimulus appropriate to the subsystem level. Application of system level stimulations to the subsystem level usually leads to significant overdesign of the subsystem which is not necessary and may impair normal subsystem performance. The second factor is the availability of test equipment needed to provide the subsystem level <span class="hlt">lightning</span> stimulation. Equipment for testing at this level should be portable or at least movable to enable efficient testing in a design <span class="hlt">laboratory</span> environment. Large fixed test installations for system level tests are not readily available for use by the design engineers at the subsystem level and usually require special operating skills. The two factors, stimulation level and test equipment availability, must be evaluated together in order to produce a practical, workable test standard. The neglect or subordination of either factor will guarantee failure in generating the standard. It is not unusual to hear that test standards or specifications are waived because a specified stimulation level cannot be accomplished by in-house or independent test facilities. Determination of subsystem <span class="hlt">lightning</span> simulation level requires a knowledge and evaluation of field coupling modes, peak and median levels of voltages and currents, bandwidths, and repetition rates. Practical limitations on test systems may require tradeoffs in <span class="hlt">lightning</span> stimulation parameters in order to build practical test equipment. Peak power levels that can be generated at specified bandwidths with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AtmRe.169..485M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AtmRe.169..485M"><span>Cloud-to-ground <span class="hlt">lightning</span> activity over Greece: Spatio-temporal analysis and impacts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Matsangouras, I. T.; Nastos, P. T.; Kapsomenakis, J.</p> <p>2016-03-01</p> <p>Cloud-to-ground (CG) <span class="hlt">lightning</span> activity recorded by the Hellenic National Meteorological Service (HNMS) Precision <span class="hlt">Lightning</span> Network (PLN) is analysed over the wider area of Greece. In addition, the spatial and temporal relationships between TRMM 3B42 (Tropical Rainfall Measuring Mission) datasets and <span class="hlt">lightning</span> are presented. The analyses concern the period from January 14, 2008 to December 31, 2012. The <span class="hlt">Laboratory</span> of Climatology and Atmospheric Environment, University of Athens, has established a detailed dataset of <span class="hlt">lightning</span> impacts over Greece from 1895 to 2013, based on digitized archive editions of newspapers. The mean seasonal variability of CG <span class="hlt">lightning</span> activity revealed autumn as the most dominant season with 303 LD, while the mean monthly variability of CG indicated October as the most <span class="hlt">lightning</span> active month and May as the month with a mean of 27 LD. The mean annual spatial distribution of CG <span class="hlt">lightning</span> per km2, depicted the maximum frequency over Pindus mountain range (> 7 CG/km2). During the autumn season, the northern Ionian Sea experienced a mean frequency of more than 5 CG/km2, compared to the southern Ionian Sea and NW Peloponnesus, where values of more than 7 CG/km2 are depicted. During the summer season, the maximum frequency appeared along Pindus mountain range, around Attica, Thessaly and central Macedonia highlands. The spatial distribution of seasonal correlations between the number of CG flashes/day and gridded (TRMM 3B42) daily rainfall totals for the period 2008-2012 over Greece, indicated that correlations were mainly positive all over the under study area, within all seasons, and especially during summer and autumn. Regarding the <span class="hlt">lightning</span> impacts in Greece, based on the 1895-2013 study period, more than 343 fatalities and at least 224 injured people have been recorded. The spatial analysis of <span class="hlt">lightning</span> impacts, showed that the majority of events has been recorded over Greek mainland and only few scattered events have been reported over</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SGeo...34..731R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SGeo...34..731R"><span>Electromagnetic Methods of <span class="hlt">Lightning</span> Detection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rakov, V. A.</p> <p>2013-11-01</p> <p>Both cloud-to-ground and cloud <span class="hlt">lightning</span> discharges involve a number of processes that produce electromagnetic field signatures in different regions of the spectrum. Salient characteristics of measured wideband electric and magnetic fields generated by various <span class="hlt">lightning</span> processes at distances ranging from tens to a few hundreds of kilometers (when at least the initial part of the signal is essentially radiation while being not influenced by ionospheric reflections) are reviewed. An overview of the various <span class="hlt">lightning</span> locating techniques, including magnetic direction finding, time-of-arrival technique, and interferometry, is given. <span class="hlt">Lightning</span> location on global scale, when radio-frequency electromagnetic signals are dominated by ionospheric reflections, is also considered. <span class="hlt">Lightning</span> locating system performance characteristics, including flash and stroke detection efficiencies, percentage of misclassified events, location accuracy, and peak current estimation errors, are discussed. Both cloud and cloud-to-ground flashes are considered. Representative examples of modern <span class="hlt">lightning</span> locating systems are reviewed. Besides general characterization of each system, the available information on its performance characteristics is given with emphasis on those based on formal ground-truth studies published in the peer-reviewed literature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20070038289&hterms=Geostationary&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DGeostationary','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20070038289&hterms=Geostationary&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DGeostationary"><span>Geostationary <span class="hlt">Lightning</span> Mapper for GOES-R</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodman, Steven; Blakeslee, Richard; Koshak, William</p> <p>2007-01-01</p> <p>The Geostationary <span class="hlt">Lightning</span> Mapper (GLM) is a single channel, near-IR optical detector, used to detect, locate and measure total <span class="hlt">lightning</span> activity over the full-disk as part of a 3-axis stabilized, geostationary weather satellite system. The next generation NOAA Geostationary Operational Environmental Satellite (GOES-R) series with a planned launch in 2014 will carry a GLM that will provide continuous day and night observations of <span class="hlt">lightning</span> from the west coast of Africa (GOES-E) to New Zealand (GOES-W) when the constellation is fully operational. The mission objectives for the GLM are to 1) provide continuous, full-disk <span class="hlt">lightning</span> measurements for storm warning and Nowcasting, 2) provide early warning of tornadic activity, and 3) accumulate a long-term database to track decadal changes of <span class="hlt">lightning</span>. The GLM owes its heritage to the NASA <span class="hlt">Lightning</span> Imaging Sensor (1997-Present) and the Optical Transient Detector (1995-2000), which were developed for the Earth Observing System and have produced a combined 11 year data record of global <span class="hlt">lightning</span> activity. Instrument formulation studies begun in January 2006 will be completed in March 2007, with implementation expected to begin in September 2007. Proxy total <span class="hlt">lightning</span> data from the NASA <span class="hlt">Lightning</span> Imaging Sensor on the Tropical Rainfall Measuring Mission (TRMM) satellite, airborne science missions (e.g., African Monsoon Multi-disciplinary Analysis, AMMA), and regional test beds (e.g, <span class="hlt">Lightning</span> Mapping Arrays) are being used to develop the pre-launch algorithms and applications, and also improve our knowledge of thunderstorm initiation and evolution. Real time <span class="hlt">lightning</span> mapping data now being provided to selected forecast offices will lead to improved understanding of the application of these data in the severe storm warning process and accelerate the development of the pre-launch algorithms and Nowcasting applications. Proxy data combined with MODIS and Meteosat Second Generation SEVERI observations will also lead to new</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040170489&hterms=Atlantic+Forest&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DAtlantic%2BForest','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040170489&hterms=Atlantic+Forest&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DAtlantic%2BForest"><span>The GOES-R <span class="hlt">Lightning</span> Mapper Sensor</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Buechler, Dennis; Christian, Hugh; Goodman, Steve</p> <p>2004-01-01</p> <p>The <span class="hlt">Lightning</span> Mapper Sensor on GOES-R builds on previous measurements of <span class="hlt">lightning</span> from low earth orbit by the OTD (Optical Transient Detector) and LIS (<span class="hlt">Lightning</span> Imaging Sensor) sensors. Unlike observations from low earth orbit, the GOES-R platform will allow continuous monitoring of <span class="hlt">lightning</span> activity over the Continental United States and southern Canada, Central and South America, and portions of the Atlantic and Pacific Oceans. The LMS will detect total (cloud-to-ground and intracloud) <span class="hlt">lightning</span> at storm scale resolution (approx. 8 km) using a highly sensitive Charge Coupled Device (CCD) detector array. Discrimination between <span class="hlt">lightning</span> optical transients and a bright sunlit background scene is accomplished by employing spectral, spatial, and temporal filtering along with a background subtraction technique. The result is 24 hour detection capability of total <span class="hlt">lightning</span>. These total <span class="hlt">lightning</span> observations can be made available to users within about 20 seconds. Research indicates a number of ways that total <span class="hlt">lightning</span> observations from LMS could benefit operational activities, including 1) potential increases in lead times and reduced false alarms for severe thunderstorm and tornado Warnings, 2) improved routing of &rail around thunderstorms, 3) support for spacecraft launches and landings, 4) improved ability to monitor tropical cyclone intensity, 5) ability to monitor thunderstorm intensification/weakening during radar outages or where radar coverage is poor, 6) better identification of deep convection for the initialization of numerical prediction models, 7) improved forest fire forecasts, 8) identification of convective initiation, 9) identification of heavy convective snowfall, and 10) enhanced temporal resolution of storm evolution (1 minute) than is available from radar observations. Total <span class="hlt">lightning</span> data has been used in an operational environment since July 2003 at the Huntsville, Alabama National Weather Service office. Total <span class="hlt">lightning</span> measurements are</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMAE42A..01C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE42A..01C"><span>Fifty Years of <span class="hlt">Lightning</span> Observations from Space</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Christian, H. J., Jr.</p> <p>2017-12-01</p> <p>Some of the earliest satellites, starting with OSO (1965), ARIEL (1967), and RAE (1968), detected <span class="hlt">lightning</span> using either optical and RF sensors, although that was not their intent. One of the earliest instruments designed to detect <span class="hlt">lightning</span> was the PBE (1977). The use of space to study <span class="hlt">lightning</span> activity has exploded since these early days. The advent of focal-plane imaging arrays made it possible to develop high performance optical <span class="hlt">lightning</span> sensors. Prior to the use of charged-coupled devices (CCD), most space-based <span class="hlt">lightning</span> sensors used only a few photo-diodes, which limited the location accuracy and detection efficiency (DE) of the instruments. With CCDs, one can limit the field of view of each detector (pixel), and thus improve the signal to noise ratio over single-detectors that summed the light reflected from many clouds with the <span class="hlt">lightning</span> produced by a single cloud. This pixelization enabled daytime DE to increase from a few percent to close to 90%. The OTD (1995), and the LIS (1997), were the first <span class="hlt">lightning</span> sensors to utilize focal-plane arrays. Together they detected global <span class="hlt">lightning</span> activity for more than twenty years, providing the first detailed information on the distribution of global <span class="hlt">lightning</span> and its variability. The FORTE satellite was launched shortly after LIS, and became the first dedicated satellite to simultaneously measure RF and optical <span class="hlt">lightning</span> emissions. It too used a CCD focal plane to detect and locate <span class="hlt">lightning</span>. In November 2016, the GLM became the first <span class="hlt">lightning</span> instrument in geostationary orbit. Shortly thereafter, China placed its GLI in orbit. <span class="hlt">Lightning</span> sensors in geostationary orbit significantly increase the value of space-based observations. For the first time, <span class="hlt">lightning</span> activity can be monitored continuously, over large areas of the Earth with high, uniform DE and location accuracy. In addition to observing standard <span class="hlt">lightning</span>, a number of sensors have been placed in orbit to detect transient luminous events and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1449067','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1449067"><span>Natural Electrotransformation of <span class="hlt">Lightning</span>-Competent Pseudomonas sp. Strain N3 in Artificial Soil Microcosms</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cérémonie, Hélène; Buret, François; Simonet, Pascal; Vogel, Timothy M.</p> <p>2006-01-01</p> <p>The <span class="hlt">lightning</span>-competent Pseudomonas sp. strain N3, recently isolated from soil, has been used to study the extent of natural electrotransformation (NET) or <span class="hlt">lightning</span> transformation as a horizontal gene transfer mechanism in soil. The variation of electrical fields applied to the soil with a <span class="hlt">laboratory</span>-scale <span class="hlt">lightning</span> system provides an estimate of the volume of soil affected by NET. Based on the range of the electric field that induces NET of Pseudomonas strain N3, the volume of soil, where NET could occur, ranges from 2 to 950 m3 per <span class="hlt">lightning</span> strike. The influence of DNA parameters (amount, size, and purity) and DNA soil residence time were also investigated. NET frequencies (electrotransformants/recipient cells) ranged from 10−8 for cell lysate after 1 day of residence in soil to 4 × 10−7 with a purified plasmid added immediately before the <span class="hlt">lightning</span>. The electrical field gradient (in kilovolts per cm) also played a role as NET frequencies ranging from 1 × 10−5 at 2.3 kV/cm to 1.7 × 10−4 at 6.5 kV/cm. PMID:16597934</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910010714','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910010714"><span>Rocket-triggered <span class="hlt">lightning</span> strikes and forest fire ignition</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fenner, James</p> <p>1990-01-01</p> <p>The following are presented: (1) background information on the rocket-triggered <span class="hlt">lightning</span> project an Kennedy Space Center (KSC); (2) a summary of the forecasting problem; (3) the facilities and equipment available for undertaking field experiments at KSC; (4) previous research activity performed; (5) a description of the atmospheric science field <span class="hlt">laboratory</span> near Mosquito Lagoon on the KSC complex; (6) methods of data acquisition; and (7) present results. New sources of data for the 1990 field experiment include measuring the electric field in the lower few thousand feet of the atmosphere by suspending field measuring devices below a tethered balloon, and measuring the electric field intensity in clouds and in the atmosphere with aircraft. The latter program began in July of 1990. Also, future prospects for both triggered <span class="hlt">lightning</span> and forest fire research at KSC are listed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840005664','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840005664"><span><span class="hlt">Lightning</span> mapper sensor design study</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Eaton, L. R.; Poon, C. W.; Shelton, J. C.; Laverty, N. P.; Cook, R. D.</p> <p>1983-01-01</p> <p>World-wide continuous measurement of <span class="hlt">lightning</span> location, intensity, and time during both day and night is to be provided by the <span class="hlt">Lightning</span> Mapper (LITMAP) instrument. A technology assessment to determine if the LITMAP requirements can be met using existing sensor and electronic technologies is presented. The baseline concept discussed in this report is a compromise among a number of opposing requirements (e.g., ground resolution versus array size; large field of view versus narrow bandpass filter). The concept provides coverage for more than 80 percent of the <span class="hlt">lightning</span> events as based on recent above-cloud NASA/U2 <span class="hlt">lightning</span> measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/20764570-bead-lightning-formation','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/20764570-bead-lightning-formation"><span>Bead <span class="hlt">lightning</span> formation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Ludwig, G.O.; Saba, M.M.F.; Division of Space Geophysics, National Space Research Institute, 12227-010, Sao Jose dos Campos, SP</p> <p>2005-09-15</p> <p>Formation of beaded structures in triggered <span class="hlt">lightning</span> discharges is considered in the framework of both magnetohydrodynamic (MHD) and hydrodynamic instabilities. It is shown that the space periodicity of the structures can be explained in terms of the kink and sausage type instabilities in a cylindrical discharge with anomalous viscosity. In particular, the fast growth rate of the hydrodynamic Rayleigh-Taylor instability, which is driven by the backflow of air into the channel of the decaying return stroke, dominates the initial evolution of perturbations during the decay of the return current. This instability is responsible for a significant enhancement of the anomalousmore » viscosity above the classical level. Eventually, the damping introduced at the current channel edge by the high level of anomalous viscous stresses defines the final length scale of bead <span class="hlt">lightning</span>. Later, during the continuing current stage of the <span class="hlt">lightning</span> flash, the MHD pinch instability persists, although with a much smaller growth rate that can be enhanced in a M-component event. The combined effect of these instabilities may explain various aspects of bead <span class="hlt">lightning</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70039773','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70039773"><span>Combining satellite-based fire observations and ground-based <span class="hlt">lightning</span> detections to identify <span class="hlt">lightning</span> fires across the conterminous USA</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Bar-Massada, A.; Hawbaker, T.J.; Stewart, S.I.; Radeloff, V.C.</p> <p>2012-01-01</p> <p><span class="hlt">Lightning</span> fires are a common natural disturbance in North America, and account for the largest proportion of the area burned by wildfires each year. Yet, the spatiotemporal patterns of <span class="hlt">lightning</span> fires in the conterminous US are not well understood due to limitations of existing fire databases. Our goal here was to develop and test an algorithm that combined MODIS fire detections with <span class="hlt">lightning</span> detections from the National <span class="hlt">Lightning</span> Detection Network to identify <span class="hlt">lightning</span> fires across the conterminous US from 2000 to 2008. The algorithm searches for spatiotemporal conjunctions of MODIS fire clusters and NLDN detected <span class="hlt">lightning</span> strikes, given a spatiotemporal lag between <span class="hlt">lightning</span> strike and fire ignition. The algorithm revealed distinctive spatial patterns of <span class="hlt">lightning</span> fires in the conterminous US While a sensitivity analysis revealed that the algorithm is highly sensitive to the two thresholds that are used to determine conjunction, the density of fires it detected was moderately correlated with ground based fire records. When only fires larger than 0.4 km2 were considered, correlations were higher and the root-mean-square error between datasets was less than five fires per 625 km2 for the entire study period. Our algorithm is thus suitable for detecting broad scale spatial patterns of <span class="hlt">lightning</span> fire occurrence, and especially <span class="hlt">lightning</span> fire hotspots, but has limited detection capability of smaller fires because these cannot be consistently detected by MODIS. These results may enhance our understanding of large scale patterns of <span class="hlt">lightning</span> fire activity, and can be used to identify the broad scale factors controlling fire occurrence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080001446','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080001446"><span>Reexamination of <span class="hlt">Ball</span>-Race Conformity Effects on <span class="hlt">Ball</span> Bearing Life</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zaretsky, Erwin V.; Poplawski, Joseph V.; Root, Lawrence E.</p> <p>2007-01-01</p> <p>The analysis in this report considers the life of the <span class="hlt">ball</span> set as well as the respective lives of the races to reassess the effect of <span class="hlt">ball</span>-race conformity on <span class="hlt">ball</span> bearing life. The related changes in <span class="hlt">ball</span> bearing life are incorporated in life factors that can be used to modify the bearing predicted life using the Lundberg-Palmgren equations and the ANSI/ABMA and ISO Standards. Two simple algebraic relationships were established to calculate life factors LF(sub c) to determine the effect of inner- and outer-race conformity combinations on bearing L(sub 10) life for deepgroove and angular-contact <span class="hlt">ball</span> bearings, respectively. Depending on the bearing type and series as well as conformity combinations, the calculated life for deep-groove <span class="hlt">ball</span> bearings can be over 40 percent less than that calculated by the Lundberg-Palmgren equations. For angular-contact <span class="hlt">ball</span> bearings, the life can vary between +16 and -39 percent from that calculated by the Lundberg-Palmgren equations. Comparing the two <span class="hlt">ball</span> bearing types, the life factors LF(sub c) for the deep-groove bearings can be as much as 40 percent lower than that for angular-contact <span class="hlt">ball</span> bearings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/48025','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/48025"><span><span class="hlt">Lightning</span> fires in southwestern forests</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Jack S. Barrows</p> <p>1978-01-01</p> <p><span class="hlt">Lightning</span> is the leading cause of fires in southwestern forests. On all protected private, state and federal lands in Arizona and New Mexico, nearly 80 percent of the forest, brush and range fires are ignited by <span class="hlt">lightning</span>. The Southwestern region leads all other regions of the United States both in total number of <span class="hlt">lightning</span> fires and in the area burned by these fires...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160006716&hterms=air+quality&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dair%2Bquality','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160006716&hterms=air+quality&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dair%2Bquality"><span><span class="hlt">Lightning</span> NOx and Impacts on Air Quality</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Murray, Lee T.</p> <p>2016-01-01</p> <p><span class="hlt">Lightning</span> generates relatively large but uncertain quantities of nitrogen oxides, critical precursors for ozone and hydroxyl radical (OH), the primary tropospheric oxidants. <span class="hlt">Lightning</span> nitrogen oxide strongly influences background ozone and OH due to high ozone production efficiencies in the free troposphere, effecting small but non-negligible contributions to surface pollutant concentrations. <span class="hlt">Lightning</span> globally contributes 3-4 ppbv of simulated annual-mean policy-relevant background (PRB) surface ozone, comprised of local, regional, and hemispheric components, and up to 18 ppbv during individual events. Feedbacks via methane may counter some of these effects on decadal time scales. <span class="hlt">Lightning</span> contributes approximately 1 percent to annual-mean surface particulate matter, as a direct precursor and by promoting faster oxidation of other precursors. <span class="hlt">Lightning</span> also ignites wildfires and contributes to nitrogen deposition. Urban pollution influences <span class="hlt">lightning</span> itself, with implications for regional <span class="hlt">lightning</span>-nitrogen oxide production and feedbacks on downwind surface pollution. How <span class="hlt">lightning</span> emissions will change in a warming world remains uncertain.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SGeo...34..755P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SGeo...34..755P"><span><span class="hlt">Lightning</span> Applications in Weather and Climate Research</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Price, Colin G.</p> <p>2013-11-01</p> <p>Thunderstorms, and <span class="hlt">lightning</span> in particular, are a major natural hazard to the public, aviation, power companies, and wildfire managers. <span class="hlt">Lightning</span> causes great damage and death every year but also tells us about the inner working of storms. Since <span class="hlt">lightning</span> can be monitored from great distances from the storms themselves, <span class="hlt">lightning</span> may allow us to provide early warnings for severe weather phenomena such as hail storms, flash floods, tornadoes, and even hurricanes. <span class="hlt">Lightning</span> itself may impact the climate of the Earth by producing nitrogen oxides (NOx), a precursor of tropospheric ozone, which is a powerful greenhouse gas. Thunderstorms themselves influence the climate system by the redistribution of heat, moisture, and momentum in the atmosphere. What about future changes in <span class="hlt">lightning</span> and thunderstorm activity? Many studies show that higher surface temperatures produce more <span class="hlt">lightning</span>, but future changes will depend on what happens to the vertical temperature profile in the troposphere, as well as changes in water balance, and even aerosol loading of the atmosphere. Finally, <span class="hlt">lightning</span> itself may provide a useful tool for tracking climate change in the future, due to the nonlinear link between <span class="hlt">lightning</span>, temperature, upper tropospheric water vapor, and cloud cover.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023326','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023326"><span>Damage to metallic samples produced by measured <span class="hlt">lightning</span> currents</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fisher, Richard J.; Schnetzer, George H.</p> <p>1991-01-01</p> <p>A total of 10 sample disks of 2024-T3 aluminum and 4130 ferrous steel were exposed to rocket-triggered <span class="hlt">lightning</span> currents at the Kennedy Space Center test site. The experimental configuration was arranged so that the samples were not exposed to the preliminary streamer, wire-burn, or following currents that are associated with an upward-initiated rocket-triggered flash but which are atypical of naturally initiated <span class="hlt">lightning</span>. Return-stroke currents and continuing currents actually attaching to the sample were measured, augmented by close-up video recordings of approximately 3 feet of the channel above the sample and by 16-mm movies with 5-ms resolution. From these data it was possible to correlate individual damage spots with streamer, return-stroke, and continuing currents that produced them. Substantial penetration of 80-mil aluminum was produced by a continuing current of submedian amplitude and duration, and full penetration of a 35-mil steel sample occurred under an eightieth percentile continuing current. The primary purpose of the data acquired in these experiments is for use in improving and quantifying the fidelity of <span class="hlt">laboratory</span> simulations of <span class="hlt">lightning</span> burnthrough.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title14-vol1/pdf/CFR-2010-title14-vol1-sec25-581.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title14-vol1/pdf/CFR-2010-title14-vol1-sec25-581.pdf"><span>14 CFR 25.581 - <span class="hlt">Lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-01-01</p> <p>... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false <span class="hlt">Lightning</span> protection. 25.581 Section 25.581 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure <span class="hlt">Lightning</span> Protection § 25.581 <span class="hlt">Lightning</span> protection. (a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRD..12212296W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRD..12212296W"><span>Improving <span class="hlt">Lightning</span> and Precipitation Prediction of Severe Convection Using <span class="hlt">Lightning</span> Data Assimilation With NCAR WRF-RTFDDA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Haoliang; Liu, Yubao; Cheng, William Y. Y.; Zhao, Tianliang; Xu, Mei; Liu, Yuewei; Shen, Si; Calhoun, Kristin M.; Fierro, Alexandre O.</p> <p>2017-11-01</p> <p>In this study, a <span class="hlt">lightning</span> data assimilation (LDA) scheme was developed and implemented in the National Center for Atmospheric Research Weather Research and Forecasting-Real-Time Four-Dimensional Data Assimilation system. In this LDA method, graupel mixing ratio (qg) is retrieved from observed total <span class="hlt">lightning</span>. To retrieve qg on model grid boxes, column-integrated graupel mass is first calculated using an observation-based linear formula between graupel mass and total <span class="hlt">lightning</span> rate. Then the graupel mass is distributed vertically according to the empirical qg vertical profiles constructed from model simulations. Finally, a horizontal spread method is utilized to consider the existence of graupel in the adjacent regions of the <span class="hlt">lightning</span> initiation locations. Based on the retrieved qg fields, latent heat is adjusted to account for the latent heat releases associated with the formation of the retrieved graupel and to promote convection at the observed <span class="hlt">lightning</span> locations, which is conceptually similar to the method developed by Fierro et al. Three severe convection cases were studied to evaluate the LDA scheme for short-term (0-6 h) <span class="hlt">lightning</span> and precipitation forecasts. The simulation results demonstrated that the LDA was effective in improving the short-term <span class="hlt">lightning</span> and precipitation forecasts by improving the model simulation of the qg fields, updrafts, cold pool, and front locations. The improvements were most notable in the first 2 h, indicating a highly desired benefit of the LDA in <span class="hlt">lightning</span> and convective precipitation nowcasting (0-2 h) applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=335478','PESTICIDES'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=335478"><span>On the Relationship between Observed NLDN <span class="hlt">Lightning</span> ...</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p><span class="hlt">Lightning</span>-produced nitrogen oxides (NOX=NO+NO2) in the middle and upper troposphere play an essential role in the production of ozone (O3) and influence the oxidizing capacity of the troposphere. Despite much effort in both observing and modeling <span class="hlt">lightning</span> NOX during the past decade, considerable uncertainties still exist with the quantification of <span class="hlt">lightning</span> NOX production and distribution in the troposphere. It is even more challenging for regional chemistry and transport models to accurately parameterize <span class="hlt">lightning</span> NOX production and distribution in time and space. The Community Multiscale Air Quality Model (CMAQ) parameterizes the <span class="hlt">lightning</span> NO emissions using local scaling factors adjusted by the convective precipitation rate that is predicted by the upstream meteorological model; the adjustment is based on the observed <span class="hlt">lightning</span> strikes from the National <span class="hlt">Lightning</span> Detection Network (NLDN). For this parameterization to be valid, the existence of an a priori reasonable relationship between the observed <span class="hlt">lightning</span> strikes and the modeled convective precipitation rates is needed. In this study, we will present an analysis leveraged on the observed NLDN <span class="hlt">lightning</span> strikes and CMAQ model simulations over the continental United States for a time period spanning over a decade. Based on the analysis, new parameterization scheme for <span class="hlt">lightning</span> NOX will be proposed and the results will be evaluated. The proposed scheme will be beneficial to modeling exercises where the obs</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990079433&hterms=rain+storm&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Drain%2Bstorm','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990079433&hterms=rain+storm&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Drain%2Bstorm"><span>Characterizing the Relationships Among <span class="hlt">Lightning</span> and Storm Parameters: <span class="hlt">Lightning</span> as a Proxy Variable</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodman, S. J.; Raghavan, R.; William, E.; Weber, M.; Boldi, B.; Matlin, A.; Wolfson, M.; Hodanish, S.; Sharp. D.</p> <p>1997-01-01</p> <p>We have gained important insights from prior studies that have suggested relationships between <span class="hlt">lightning</span> and storm growth, decay, convective rain flux, vertical distribution of storm mass and echo volume in the region, and storm energetics. A study was initiated in the Summer of 1996 to determine how total (in-cloud plus ground) <span class="hlt">lightning</span> observations might provide added knowledge to the forecaster in the determination and identification of severe thunderstorms and weather hazards in real-time. The Melbourne Weather Office was selected as a primary site to conduct this study because Melbourne is the only site in the world with continuous and open access to total <span class="hlt">lightning</span> (LDAR) data and a Doppler (WSR-88D) radar. A <span class="hlt">Lightning</span> Imaging Sensor Data Applications Demonstration (LISDAD) system was integrated into the forecaster's workstation during the Summer 1996 to allow the forecaster to interact in real-time with the multi-sensor data being displayed. LISDAD currently ingests LDAR data, the cloud-to-ground National <span class="hlt">Lightning</span> Detection Network (NLDN) data, and the Melbourne radar data in f real-time. The interactive features provide the duty forecaster the ability to perform quick diagnostics on storm cells of interest. Upon selection of a storm cell, a pop-up box appears displaying the time-history of various storm parameters (e.g., maximum radar reflectivity, height of maximum reflectivity, echo-top height, NLDN and LDAR <span class="hlt">lightning</span> flash rates, storm-based vertically integrated liquid water content). This product is archived to aid on detailed post-analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70046526','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70046526"><span><span class="hlt">Ball</span> clay</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Virta, R.L.</p> <p>2013-01-01</p> <p>Four companies — H.C. Spinks Clay Co., Inc., Imerys, Old Hickory Clay Co. and Unimin Corp. — mined <span class="hlt">ball</span> clay in five U.S. states in 2012. Production, on the basis of preliminary data, was 900 kt (992,000 st), with an estimated value of $42.3 million. This was a slight increase in tonnage from 886 kt (977,000 st), with a value of $40.9 million in 2011. Tennessee was the leading <span class="hlt">ball</span> clay producing state, with 63 percent of domestic production, followed by Texas, Mississippi, Kentucky and Indiana. Reported <span class="hlt">ball</span> clay production from Indiana probably was fire clay rather than <span class="hlt">ball</span> clay. About 69 percent of total <span class="hlt">ball</span> clay production was airfloat, 20 percent was crude and 11 percent was water-slurried.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/874377','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/874377"><span><span class="hlt">Ball</span> valve extractor</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Herndon, Charles; Brown, Roger A.</p> <p>2002-01-01</p> <p>An apparatus and process for removing a <span class="hlt">ball</span> valve is provided. The <span class="hlt">ball</span> valve removal tool provides a handle sliding along the length of a shaft. One end of the shaft is secured within an interior cavity of a <span class="hlt">ball</span> valve while the opposite end of the shaft defines a stop member. By providing a manual sliding force to the handle, the handle impacts the stop member and transmits the force to the <span class="hlt">ball</span> valve. The direction of the force is along the shaft of the removal tool and disengages the <span class="hlt">ball</span> valve from the <span class="hlt">ball</span> valve housing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMAE23A..01L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMAE23A..01L"><span>Toward a Time-Domain Fractal <span class="hlt">Lightning</span> Simulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liang, C.; Carlson, B. E.; Lehtinen, N. G.; Cohen, M.; Lauben, D.; Inan, U. S.</p> <p>2010-12-01</p> <p>Electromagnetic simulations of <span class="hlt">lightning</span> are useful for prediction of <span class="hlt">lightning</span> properties and exploration of the underlying physical behavior. Fractal <span class="hlt">lightning</span> models predict the spatial structure of the discharge, but thus far do not provide much information about discharge behavior in time and therefore cannot predict electromagnetic wave emissions or current characteristics. Here we develop a time-domain fractal <span class="hlt">lightning</span> simulation from Maxwell's equations, the method of moments with the thin wire approximation, an adaptive time-stepping scheme, and a simplified electrical model of the <span class="hlt">lightning</span> channel. The model predicts current pulse structure and electromagnetic wave emissions and can be used to simulate the entire duration of a <span class="hlt">lightning</span> discharge. The model can be used to explore the electrical characteristics of the <span class="hlt">lightning</span> channel, the temporal development of the discharge, and the effects of these characteristics on observable electromagnetic wave emissions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850067258&hterms=ATLA&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DATLA','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850067258&hterms=ATLA&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DATLA"><span><span class="hlt">Lightning</span> on Venus</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scarf, F. L.</p> <p>1985-01-01</p> <p>On the night side of Venus, the plasma wave instrument on the Pioneer-Venus Orbiter frequently detects strong and impulsive low-frequency noise bursts when the local magnetic field is strong and steady and when the field is oriented to point down to the ionosphere. The signals have characteristics of <span class="hlt">lightning</span> whistlers, and an attempt was made to identify the sources by tracing rays along the B-field from the Orbiter down toward the surface. An extensive data set strongly indicates a clustering of <span class="hlt">lightning</span> sources near the Beta and Phoebe Regios, with additional significant clustering near the Atla Regio at the eastern edge of Aphrodite Terra. These results suggest that there are localized <span class="hlt">lightning</span> sources at or near the planetary surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006IJTFM.126...71D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006IJTFM.126...71D"><span>Analysis of <span class="hlt">Lightning</span>-induced Impulse Magnetic Fields in the Building with an Insulated Down Conductor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Du, Patrick Y.; Zhou, Qi-Bin</p> <p></p> <p>This paper presents an analysis of <span class="hlt">lightning</span>-induced magnetic fields in a building. The building of concern is protected by the <span class="hlt">lightning</span> protection system with an insulated down conductor. In this paper a system model for metallic structure of the building is constructed first using the circuit approach. The circuit model of the insulated down conductor is discussed extensively, and explicit expressions of the circuit parameters are presented. The system model was verified experimentally in the <span class="hlt">laboratory</span>. The modeling approach is applied to analyze the impulse magnetic fields in a full-scale building during a direct <span class="hlt">lightning</span> strike. It is found that the impulse magnetic field is significantly high near the down conductor. The field is attenuated if the down conductor is moved to a column in the building. The field can be reduced further if the down conductor is housed in an earthed metal pipe. Recommendations for protecting critical equipment against <span class="hlt">lightning</span>-induced magnetic fields are also provided in the paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27872403','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27872403"><span>Biomechanical Analysis of Weighted-<span class="hlt">Ball</span> Exercises for Baseball Pitchers.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fleisig, Glenn S; Diffendaffer, Alek Z; Aune, Kyle T; Ivey, Brett; Laughlin, Walter A</p> <p></p> <p>Weighted-<span class="hlt">ball</span> throwing programs are commonly used in training baseball pitchers to increase <span class="hlt">ball</span> velocity. The purpose of this study was to compare kinematics and kinetics among weighted-<span class="hlt">ball</span> exercises with values from standard pitching (ie, pitching standard 5-oz baseballs from a mound). <span class="hlt">Ball</span> and arm velocities would be greater with lighter <span class="hlt">balls</span> and joint kinetics would be greater with heavier <span class="hlt">balls</span>. Controlled <span class="hlt">laboratory</span> study. Twenty-five high school and collegiate baseball pitchers experienced with weighted-<span class="hlt">ball</span> throwing were tested with an automated motion capture system. Each participant performed 3 trials of 10 different exercises: pitching 4-, 5-, 6-, and 7-oz baseballs from a mound; flat-ground crow hop throws with 4-, 5-, 6-, and 7-oz baseballs; and flat-ground hold exercises with 14- and 32-oz <span class="hlt">balls</span>. Twenty-six biomechanical parameters were computed for each trial. Data among the 10 exercises were compared with repeated measures analysis of variance and post hoc paired t tests against the standard pitching data. <span class="hlt">Ball</span> velocity increased as <span class="hlt">ball</span> mass decreased. There were no differences in arm and trunk velocities between throwing a standard baseball and an underweight baseball (4 oz), while arm and trunk velocities steadily decreased as <span class="hlt">ball</span> weight increased from 5 to 32 oz. Compared with values pitching from a mound, velocities of the pelvis, shoulder, and <span class="hlt">ball</span> were increased for flat-ground throws. In general, as <span class="hlt">ball</span> mass increased arm torques and forces decreased; the exception was elbow flexion torque, which was significantly greater for the flat-ground holds. There were significant differences in body positions when pitching on the mound, flat-ground throws, and holds. While <span class="hlt">ball</span> velocity was greatest throwing underweight baseballs, results from the study did not support the rest of the hypothesis. Kinematics and kinetics were similar between underweight and standard baseballs, while overweight <span class="hlt">balls</span> correlated with decreased arm forces, torques</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010ems..confE.192G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010ems..confE.192G"><span>Ten years of <span class="hlt">Lightning</span> Imaging Sensor (LIS) data: Preparing the way for geostationary <span class="hlt">lightning</span> imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grandell, J.; Stuhlmann, R.</p> <p>2010-09-01</p> <p>The <span class="hlt">Lightning</span> Imaging Sensor (LIS) onboard the Tropical Rainfall Measurement Mission (TRMM) platform has provided a continuous source of <span class="hlt">lightning</span> observations in the +/- 35 deg latitude region since 1998. LIS, together with its predecessor Optical Transient Detector (OTD) have established an unprecedented database of optical observations of <span class="hlt">lightning</span> from a low-earth orbit, allowing a more consistent and uniform view of <span class="hlt">lightning</span> that has been available from any ground-based system so far. The main disadvantage of LIS is that, since it operates on a low-earth orbit with a low inclination, only a small part of the globe is viewed at a time and only for a duration of ~2 minutes, and for a rapidly changing phenomenon like convection and the <span class="hlt">lightning</span> related thereto this is far from optimal. This temporal sampling deficiency can, however, be overcome with observations from a geostationary orbit. One such mission in preparation is the <span class="hlt">Lightning</span> Imager on-board the Meteosat Third Generation (MTG) satellite, which will provide service continuation to the Meteosat Second Generation (MSG) system from 2018 onwards. The current MSG system has become the primary European source of geostationary observations over Europe and Africa with the start of nominal operations in January 2004, and will be delivering observations and services at least until 2017. However, considering the typical development cycle for a new complex space system, it was already for a longer time necessary to plan for and define the MTG system. MTG needs to be available around 2016, before the end of the nominal lifetime of MSG-3. One of the new missions selected for MTG is the previously mentioned <span class="hlt">Lightning</span> Imager (LI) mission, detecting continuously over almost the full disc the <span class="hlt">lightning</span> discharges taking place in clouds or between cloud and ground with a resolution around 10 km. The LI mission is intended to provide a real time <span class="hlt">lightning</span> detection (cloud-to-cloud and cloud-to-ground strokes) and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140008786','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140008786"><span>Total <span class="hlt">Lightning</span> as an Indicator of Mesocyclone Behavior</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stough, Sarah M.; Carey, Lawrence D.; Schultz, Christopher J.</p> <p>2014-01-01</p> <p>Apparent relationship between total <span class="hlt">lightning</span> (in-cloud and cloud to ground) and severe weather suggests its operational utility. Goal of fusion of total <span class="hlt">lightning</span> with proven tools (i.e., radar <span class="hlt">lightning</span> algorithms. Preliminary work here investigates circulation from Weather Suveilance Radar- 1988 Doppler (WSR-88D) coupled with total <span class="hlt">lightning</span> data from <span class="hlt">Lightning</span> Mapping Arrays.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70045429','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70045429"><span><span class="hlt">Ball</span> clay</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Virta, R.L.</p> <p>2000-01-01</p> <p>Part of the 1999 Industrial Minerals Review. The state of the <span class="hlt">ball</span> clay industry in 1999 is presented. Record highs in the sales and use of <span class="hlt">ball</span> clay were attained in 1999 due to the continued strength of the U.S. economy. U.S. production was estimated at 1.25 million st for the year, with more than half of that amount mined in Tennessee. Details of the consumption, price, imports, and exports of <span class="hlt">ball</span> clay in 1999 and the outlook for <span class="hlt">ball</span> clay over the next few years are provided.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/9614008','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/9614008"><span><span class="hlt">Lightning</span>-associated deaths--United States, 1980-1995.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p></p> <p>1998-05-22</p> <p>A <span class="hlt">lightning</span> strike can cause death or various injuries to one or several persons. The mechanism of injury is unique, and the manifestations differ from those of other electrical injuries. In the United States, <span class="hlt">lightning</span> causes more deaths than do most other natural hazards (e.g., hurricanes and tornadoes), although the incidence of <span class="hlt">lightning</span>-related deaths has decreased since the 1950s. The cases described in this report illustrate diverse circumstances in which deaths attributable to <span class="hlt">lightning</span> can occur. This report also summarizes data from the Compressed Mortality File of CDC's National Center for Health Statistics on <span class="hlt">lightning</span> fatalities in the United States from 1980 through 1995, when 1318 deaths were attributed to <span class="hlt">lightning</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25478304','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25478304"><span>Tropic <span class="hlt">lightning</span>: myth or menace?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>McCarthy, John</p> <p>2014-11-01</p> <p><span class="hlt">Lightning</span> is one of the leading causes of death related to environmental disaster. Of all <span class="hlt">lightning</span> fatalities documented between 2006 and 2012, leisure activities contributed the largest proportion of deaths, with water-associated, sports, and camping being the most common. Despite the prevalence of these activities throughout the islands, Hawai'i has had zero documented <span class="hlt">lightning</span> fatalities since weather data tracking was initiated in 1959. There is a common misconception that <span class="hlt">lightning</span> does not strike the ground in Hawai'i. This myth may contribute to a potentially dangerous false sense of security, and recognition of warning signs and risk factor modification remain the most important prevention strategies. <span class="hlt">Lightning</span> damage occurs on a spectrum, from minor burns to multi-organ dysfunction. After injury, initial treatment should focus on "reverse triage" and immediate cardiopulmonary resuscitation when indicated, followed by transfer to a healthcare facility. Definitive treatment entails monitoring and management of potential sequelae, to include cardiovascular, neurologic, dermatologic, ophthalmologic, audiovestibular, and psychiatric complications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1982fugv.rept.....D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1982fugv.rept.....D"><span><span class="hlt">Lightning</span> protection of distribution systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Darveniza, M.; Uman, M. A.</p> <p>1982-09-01</p> <p>Research work on the <span class="hlt">lightning</span> protection of distribution systems is described. The rationale behind the planning of the first major phase of the work - the field experiments conducted in the Tampa Bay area during August 1978 and July to September 1979 is explained. The aims of the field work were to characterize <span class="hlt">lightning</span> in the Tampa Bay area, and to identify the <span class="hlt">lightning</span> parameters associated with the occurrence of line outages and equipment damage on the distribution systems of the participating utilities. The equipment developed for these studies is fully described. The field work provided: general data on <span class="hlt">lightning</span> - e.g., electric and magnetic fields of cloud and ground flashes; data from automated monitoring of <span class="hlt">lightning</span> activity; stroke current waveshapes and peak currents measured at distribution arresters; and line outage and equipment damage on 13 kV networks in the Tampa Bay area. Computer aided analyses were required to collate and to process the accumulated data. The computer programs developed for this work are described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4244891','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4244891"><span>Tropic <span class="hlt">Lightning</span>: Myth or Menace?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2014-01-01</p> <p><span class="hlt">Lightning</span> is one of the leading causes of death related to environmental disaster. Of all <span class="hlt">lightning</span> fatalities documented between 2006 and 2012, leisure activities contributed the largest proportion of deaths, with water-associated, sports, and camping being the most common. Despite the prevalence of these activities throughout the islands, Hawai‘i has had zero documented <span class="hlt">lightning</span> fatalities since weather data tracking was initiated in 1959. There is a common misconception that <span class="hlt">lightning</span> does not strike the ground in Hawai‘i. This myth may contribute to a potentially dangerous false sense of security, and recognition of warning signs and risk factor modification remain the most important prevention strategies. <span class="hlt">Lightning</span> damage occurs on a spectrum, from minor burns to multi-organ dysfunction. After injury, initial treatment should focus on “reverse triage” and immediate cardiopulmonary resuscitation when indicated, followed by transfer to a healthcare facility. Definitive treatment entails monitoring and management of potential sequelae, to include cardiovascular, neurologic, dermatologic, ophthalmologic, audiovestibular, and psychiatric complications. PMID:25478304</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19704405','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19704405"><span>Fatal <span class="hlt">lightning</span> strikes in Malaysia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Murty, O P; Kian, Chong Kah; Ari Husin, Mohammed Husrul; Nanta Kumar, Ranjeev Kumar; Mohammed Yusuf, Wan Yuhana W</p> <p>2009-09-01</p> <p><span class="hlt">Lightning</span> strike is a natural phenomenon with potentially devastating effects and represents one of the important causes of deaths from environmental phenomena. Almost every organ system may be affected as <span class="hlt">lightning</span> current passes through the human body taking the shortest pathways between the contact points. A 10 years retrospective study (1996-2005) was conducted at University Hospital Kuala Lumpur (20 cases) also including cases during last 3 years from Hospital Tengku Ampuan Rahimah, Klang (7 cases) from the autopsy reports at Forensic Pathology Units of these 2 hospitals. Both these hospitals are attached to University of Malaya. There were 27 fatal cases of <span class="hlt">lightning</span> strike with male preponderance(92.59%) and male to female ratio of 12.5:1. Majority of victims of <span class="hlt">lightning</span> strike were from the age group between 30 and 39 years old. Most of the victims were foreign workers. Indonesians workers contributed to 59.26% of overall cases. Majority of them were construction workers who attributed i.e.11 of 27 cases (40.74%). Most of the victims were brought in dead (37.04%). In majority of the cases the <span class="hlt">lightning</span> incidence occurred in the evenings, with the frequency of 15 of 27 cases (62.5%). The month of December represented with the highest number of cases (5 cases of 23 cases); 2004 had the highest incidence of <span class="hlt">lightning</span> strike which was 5 (19.23%). <span class="hlt">Lightning</span> strike incidence occurred when victims had taken shelter (25.9%) under trees or shades. <span class="hlt">Lightning</span> strike in open areas occurred in 10 of 27 cases (37.0%). Head and neck were the most commonly affected sites with the incidence of 77.78% and 74% respectively in all the victims. Only 29.63% of the cases presented with ear bleeding.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Inertia&pg=2&id=EJ984077','ERIC'); return false;" href="https://eric.ed.gov/?q=Inertia&pg=2&id=EJ984077"><span>Moment of Inertia of a Ping-Pong <span class="hlt">Ball</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Cao, Xian-Sheng</p> <p>2012-01-01</p> <p>This note describes how to theoretically calculate and experimentally measure the moment of inertia of a Ping-Pong[R] <span class="hlt">ball</span>. The theoretical calculation results are in good agreement with the experimental measurements that can be reproduced in an introductory physics <span class="hlt">laboratory</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940018765','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940018765"><span><span class="hlt">Lightning</span> studies using LDAR and LLP data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Forbes, Gregory S.</p> <p>1993-01-01</p> <p>This study intercompared <span class="hlt">lightning</span> data from LDAR and LLP systems in order to learn more about the spatial relationships between thunderstorm electrical discharges aloft and <span class="hlt">lightning</span> strikes to the surface. The ultimate goal of the study is to provide information that can be used to improve the process of real-time detection and warning of <span class="hlt">lightning</span> by weather forecasters who issue <span class="hlt">lightning</span> advisories. The <span class="hlt">Lightning</span> Detection and Ranging (LDAR) System provides data on electrical discharges from thunderstorms that includes cloud-ground flashes as well as <span class="hlt">lightning</span> aloft (within cloud, cloud-to-cloud, and sometimes emanating from cloud to clear air outside or above cloud). The <span class="hlt">Lightning</span> Location and Protection (LLP) system detects primarily ground strikes from <span class="hlt">lightning</span>. Thunderstorms typically produce LDAR signals aloft prior to the first ground strike, so that knowledge of preferred positions of ground strikes relative to the LDAR data pattern from a thunderstorm could allow advance estimates of enhanced ground strike threat. Studies described in the report examine the position of LLP-detected ground strikes relative to the LDAR data pattern from the thunderstorms. The report also describes other potential approaches to the use of LDAR data in the detection and forecasting of <span class="hlt">lightning</span> ground strikes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120016612','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120016612"><span>Camp Blanding <span class="hlt">Lightning</span> Mapping Array</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Blakeslee,Richard; Christian, Hugh; Bailey, Jeffrey; Hall, John; Uman, Martin; Jordan, Doug; Krehbiel, Paul; Rison, William; Edens, Harald</p> <p>2011-01-01</p> <p>A seven station, short base-line <span class="hlt">Lightning</span> Mapping Array was installed at the Camp Blanding International Center for <span class="hlt">Lightning</span> Research and Testing (ICLRT) during April 2011. This network will support science investigations of Terrestrial Gamma-Ray Flashes (TGFs) and <span class="hlt">lightning</span> initiation using rocket triggered <span class="hlt">lightning</span> at the ICLRT. The network operations and data processing will be carried out through a close collaboration between several organizations, including the NASA Marshall Space Flight Center, University of Alabama in Huntsville, University of Florida, and New Mexico Tech. The deployment was sponsored by the Defense Advanced Research Projects Agency (DARPA). The network does not have real-time data dissemination. Description, status and plans will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhDT........48T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhDT........48T"><span>A comparison of two ground-based <span class="hlt">lightning</span> detection networks against the satellite-based <span class="hlt">lightning</span> imaging sensor (LIS)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thompson, Kelsey B.</p> <p></p> <p>We compared <span class="hlt">lightning</span> stroke data from the ground-based World Wide <span class="hlt">Lightning</span> Location Network (WWLLN) and <span class="hlt">lightning</span> stroke data from the ground-based Earth Networks Total <span class="hlt">Lightning</span> Network (ENTLN) to <span class="hlt">lightning</span> group data from the satellite-based <span class="hlt">Lightning</span> Imaging Sensor (LIS) from 1 January 2010 through 30 June 2011. The region of study, about 39°S to 39°N latitude, 164°E to 17°W longitude, chosen to approximate the Geostationary <span class="hlt">Lightning</span> Mapper (GLM) field of view, was considered in its entirety and then divided into four geographical sub-regions. We found the highest 18-mon WWLLN coincidence percent (CP) value in the Pacific Ocean at 18.9% and the highest 18-mon ENTLN CP value in North America at 63.3%. We found the lowest 18-mon CP value for both WWLLN and ENTLN in South America at 6.2% and 2.2% respectively. Daily CP values and how often large radiance LIS groups had a coincident stroke varied. Coincidences between LIS groups and ENTLN strokes often resulted in more cloud than ground coincidences in North America and more ground than cloud coincidences in the other three sub-regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title14-vol4/pdf/CFR-2011-title14-vol4-sec420-71.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title14-vol4/pdf/CFR-2011-title14-vol4-sec420-71.pdf"><span>14 CFR 420.71 - <span class="hlt">Lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-01-01</p> <p>... path connecting an air terminal to an earth electrode system. (iii) Earth electrode system. An earth... to the initiation of explosives by <span class="hlt">lightning</span>. (1) Elements of a lighting protection system. Unless an... facilities shall have a <span class="hlt">lightning</span> protection system to ensure explosives are not initiated by <span class="hlt">lightning</span>. A...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title14-vol4/pdf/CFR-2012-title14-vol4-sec420-71.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title14-vol4/pdf/CFR-2012-title14-vol4-sec420-71.pdf"><span>14 CFR 420.71 - <span class="hlt">Lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-01-01</p> <p>... path connecting an air terminal to an earth electrode system. (iii) Earth electrode system. An earth... to the initiation of explosives by <span class="hlt">lightning</span>. (1) Elements of a lighting protection system. Unless an... facilities shall have a <span class="hlt">lightning</span> protection system to ensure explosives are not initiated by <span class="hlt">lightning</span>. A...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title14-vol4/pdf/CFR-2014-title14-vol4-sec420-71.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title14-vol4/pdf/CFR-2014-title14-vol4-sec420-71.pdf"><span>14 CFR 420.71 - <span class="hlt">Lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-01-01</p> <p>... path connecting an air terminal to an earth electrode system. (iii) Earth electrode system. An earth... to the initiation of explosives by <span class="hlt">lightning</span>. (1) Elements of a lighting protection system. Unless an... facilities shall have a <span class="hlt">lightning</span> protection system to ensure explosives are not initiated by <span class="hlt">lightning</span>. A...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title14-vol4/pdf/CFR-2013-title14-vol4-sec420-71.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title14-vol4/pdf/CFR-2013-title14-vol4-sec420-71.pdf"><span>14 CFR 420.71 - <span class="hlt">Lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-01-01</p> <p>... path connecting an air terminal to an earth electrode system. (iii) Earth electrode system. An earth... to the initiation of explosives by <span class="hlt">lightning</span>. (1) Elements of a lighting protection system. Unless an... facilities shall have a <span class="hlt">lightning</span> protection system to ensure explosives are not initiated by <span class="hlt">lightning</span>. A...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18395987','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18395987"><span><span class="hlt">Lightning</span> injury: a review.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ritenour, Amber E; Morton, Melinda J; McManus, John G; Barillo, David J; Cancio, Leopoldo C</p> <p>2008-08-01</p> <p><span class="hlt">Lightning</span> is an uncommon but potentially devastating cause of injury in patients presenting to burn centers. These injuries feature unusual symptoms, high mortality, and significant long-term morbidity. This paper will review the epidemiology, physics, clinical presentation, management principles, and prevention of <span class="hlt">lightning</span> injuries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22104330','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22104330"><span>Secondary missile injury from <span class="hlt">lightning</span> strike.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Blumenthal, Ryan</p> <p>2012-03-01</p> <p>A 48-year-old-woman was struck dead by <span class="hlt">lightning</span> on October 24, 2010, in Pretoria, South Africa. The cause of death was due to direct <span class="hlt">lightning</span> strike. Examination showed secondary missile injury on her legs. This secondary missile (shrapnel) injury was caused by the <span class="hlt">lightning</span> striking the concrete pavement next to her. Small pieces of concrete were located embedded within the shrapnel wounds. This case report represents the first documented case of secondary missile formation (shrapnel injury) due to <span class="hlt">lightning</span> strike in the literature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910062167&hterms=How+tornadoes+formed&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DHow%2Btornadoes%2Bformed','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910062167&hterms=How+tornadoes+formed&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DHow%2Btornadoes%2Bformed"><span>Cloud-to-ground <span class="hlt">lightning</span> in a tornadic storm on 8 May 1986</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Macgorman, Donald R.; Nielsen, Kurt E.</p> <p>1991-01-01</p> <p>The National Severe Storms <span class="hlt">Laboratory</span> (NSSL) gathered Doppler radar and <span class="hlt">lightning</span> ground strike data on a supercell storm that produced three tornadoes, including an F3 tornado in Edmond, Oklahoma, approximately 40 km north of NSSL. The Edmond storm formed 30 km ahead of a storm complex and developed its first and most damaging tornado just as the storm complex started to overtake it from the west. <span class="hlt">Lightning</span> strike locations tended to concentrate just north of the mesocyclone, close to and inside a 50 dBZ reflectivity core. Positive ground flashes began just prior to the storm becoming tornadic, and positive flash rates peaked during the tornadic stage of the storm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22486500-note-lightning-temperature','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22486500-note-lightning-temperature"><span>Note on <span class="hlt">lightning</span> temperature</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Alanakyan, Yu. R., E-mail: yralanak@mail.ru</p> <p>2015-10-15</p> <p>In this paper, some features of the dynamics of a <span class="hlt">lightning</span> channel that emerges after the leader-streamer process, are theoretically studied. It is shown that the dynamic pinch effect in the channel becomes possible if a discharge current before the main (quasi-steady) stage of a <span class="hlt">lightning</span> discharge increases rapidly. The ensuing magnetic compression of the channel increases plasma temperature to several million degrees leading to a soft x-ray flash within the highly ionized plasma. The relation between the plasma temperature and the channel radius during the main stage of a <span class="hlt">lightning</span> discharge is derived.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17520964','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17520964"><span>Filigree burn of <span class="hlt">lightning</span>: two case reports.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kumar, Virendra</p> <p>2007-04-01</p> <p><span class="hlt">Lightning</span> is a powerful natural electrostatic discharge produced during a thunderstorm. The electric current passing through the discharge channels is direct with a potential of 1000 million volts or more. <span class="hlt">Lightning</span> can kill or injure a person by a direct strike, a side-flash, or conduction through another object. <span class="hlt">Lightning</span> can cause a variety of injuries in the skin and the cardiovascular, neurological and ophthalmic systems. Filigree burn of <span class="hlt">lightning</span> is a superficial burn and very rare. Two cases of death from <span class="hlt">lightning</span> which have this rare finding are reported and discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMAE24A..05F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMAE24A..05F"><span>Monitoring <span class="hlt">lightning</span> from space with TARANIS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farges, T.; Blanc, E.; Pinçon, J.</p> <p>2010-12-01</p> <p>Some recent space experiments, e.g. OTD, LIS, show the large interest of <span class="hlt">lightning</span> monitoring from space and the efficiency of optical measurement. Future instrumentations are now defined for the next generation of geostationary meteorology satellites. Calibration of these instruments requires ground truth events provided by <span class="hlt">lightning</span> location networks, as NLDN in US, and EUCLID or LINET in Europe, using electromagnetic observations at a regional scale. One of the most challenging objectives is the continuous monitoring of the <span class="hlt">lightning</span> activity over the tropical zone (Africa, America, and Indonesia). However, one difficulty is the lack of <span class="hlt">lightning</span> location networks at regional scale in these areas to validate the data quality. TARANIS (Tool for the Analysis of Radiations from <span class="hlt">lightNings</span> and Sprites) is a CNES micro satellite project. It is dedicated to the study of impulsive transfers of energy, between the Earth atmosphere and the space environment, from nadir observations of Transient Luminous Events (TLEs), Terrestrial Gamma ray Flashes (TGFs) and other possible associated emissions. Its orbit will be sun-synchronous at 10:30 local time; its altitude will be 700 km. Its lifetime will be nominally 2 years. Its payload is composed of several electromagnetic instruments in different wavelengths: X and gamma-ray detectors, optical cameras and photometers, electromagnetic wave sensors from DC to 30 MHz completed by high energy electron detectors. The optical instrument includes 2 cameras and 4 photometers. All sensors are equipped with filters for sprite and <span class="hlt">lightning</span> differentiation. The filters of cameras are designed for sprite and <span class="hlt">lightning</span> observations at 762 nm and 777 nm respectively. However, differently from OTD or LIS instruments, the filter bandwidth and the exposure time (respectively 10 nm and 91 ms) prevent <span class="hlt">lightning</span> optical observations during daytime. The camera field of view is a square of 500 km at ground level with a spatial sampling frequency of</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120003532','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120003532"><span>Using Cloud-to-Ground <span class="hlt">Lightning</span> Climatologies to Initialize Gridded <span class="hlt">Lightning</span> Threat Forecasts for East Central Florida</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lambert, Winnie; Sharp, David; Spratt, Scott; Volkmer, Matthew</p> <p>2005-01-01</p> <p>Each morning, the forecasters at the National Weather Service in Melbourn, FL (NWS MLB) produce an experimental cloud-to-ground (CG) <span class="hlt">lightning</span> threat index map for their county warning area (CWA) that is posted to their web site (http://www.srh.weather.gov/mlb/ghwo/<span class="hlt">lightning</span>.shtml) . Given the hazardous nature of <span class="hlt">lightning</span> in central Florida, especially during the warm season months of May-September, these maps help users factor the threat of <span class="hlt">lightning</span>, relative to their location, into their daily plans. The maps are color-coded in five levels from Very Low to Extreme, with threat level definitions based on the probability of <span class="hlt">lightning</span> occurrence and the expected amount of CG activity. On a day in which thunderstorms are expected, there are typically two or more threat levels depicted spatially across the CWA. The locations of relative <span class="hlt">lightning</span> threat maxima and minima often depend on the position and orientation of the low-level ridge axis, forecast propagation and interaction of sea/lake/outflow boundaries, expected evolution of moisture and stability fields, and other factors that can influence the spatial distribution of thunderstorms over the CWA. The <span class="hlt">lightning</span> threat index maps are issued for the 24-hour period beginning at 1200 UTC (0700 AM EST) each day with a grid resolution of 5 km x 5 km. Product preparation is performed on the AWIPS Graphical Forecast Editor (GFE), which is the standard NWS platform for graphical editing. Currently, the forecasters create each map manually, starting with a blank map. To improve efficiency of the forecast process, NWS MLB requested that the Applied Meteorology Unit (AMU) create gridded warm season <span class="hlt">lightning</span> climatologies that could be used as first-guess inputs to initialize <span class="hlt">lightning</span> threat index maps. The gridded values requested included CG strike densities and frequency of occurrence stratified by synoptic-scale flow regime. The intent is to increase consistency between forecasters while enabling them to focus on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70044846','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70044846"><span><span class="hlt">Ball</span> clay</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Virta, Robert L.</p> <p>2010-01-01</p> <p>The article reports on the global market performance of <span class="hlt">ball</span> clay in 2009 and presents an outlook for its 2010 performance. Several companies mined <span class="hlt">ball</span> call in the country including Old Hickey Clay Co., Kentucky-Tennessee Clay Co., and H.C. Spinks Clay Co. Information on the decline in <span class="hlt">ball</span> clay imports and exports is also presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28738899','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28738899"><span>A rare manifestation of burns after <span class="hlt">lightning</span> strike in rural Ghana: a case report.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Apanga, Paschal Awingura; Azumah, John Atigiba; Yiranbon, Joseph Bayewala</p> <p>2017-07-25</p> <p><span class="hlt">Lightning</span> is a natural phenomenon that mostly affects countries in the tropical and subtropical regions of the globe, including Ghana. <span class="hlt">Lightning</span> strikes pose a global public health issue. Although strikes to humans are uncommon, it is associated with high morbidity and mortality. We present a case of a 10-year-old Ghanaian girl who got second-degree burns after being struck by <span class="hlt">lightning</span>. She was put on an intravenous broad-spectrum antibiotic (ceftriaxone), Ringer's lactate, and her burns were dressed with sterile gauze impregnated with Vaseline (petroleum jelly) and silver sulfadiazine ointment. There was marked improvement on the 16 th day of treatment despite the lack in capacity of the hospital to carry out some <span class="hlt">laboratory</span> diagnostic tests. On the 21 st day of treatment, the burns were completely healed without scars and contractures. This is evidence of burns due to <span class="hlt">lightning</span> strike, despite its rare occurrence. This report will help inform those in doubt, particularly in communities where <span class="hlt">lightning</span> injuries are associated with widespread superstition. The case report also revealed how rural healthcare can be challenging amid a lack of basic diagnostic equipment and logistics. However, in resource-limited settings, Vaseline (petroleum jelly) and silver sulfadiazine could be used in the treatment of burns.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018EP%26S...70...88T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018EP%26S...70...88T"><span>Initiation of a <span class="hlt">lightning</span> search using the <span class="hlt">lightning</span> and airglow camera onboard the Venus orbiter Akatsuki</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takahashi, Yukihiro; Sato, Mitsuteru; Imai, Masataka; Lorenz, Ralph; Yair, Yoav; Aplin, Karen; Fischer, Georg; Nakamura, Masato; Ishii, Nobuaki; Abe, Takumi; Satoh, Takehiko; Imamura, Takeshi; Hirose, Chikako; Suzuki, Makoto; Hashimoto, George L.; Hirata, Naru; Yamazaki, Atsushi; Sato, Takao M.; Yamada, Manabu; Murakami, Shin-ya; Yamamoto, Yukio; Fukuhara, Tetsuya; Ogohara, Kazunori; Ando, Hiroki; Sugiyama, Ko-ichiro; Kashimura, Hiroki; Ohtsuki, Shoko</p> <p>2018-05-01</p> <p>The existence of <span class="hlt">lightning</span> discharges in the Venus atmosphere has been controversial for more than 30 years, with many positive and negative reports published. The <span class="hlt">lightning</span> and airglow camera (LAC) onboard the Venus orbiter, Akatsuki, was designed to observe the light curve of possible flashes at a sufficiently high sampling rate to discriminate <span class="hlt">lightning</span> from other sources and can thereby perform a more definitive search for optical emissions. Akatsuki arrived at Venus during December 2016, 5 years following its launch. The initial operations of LAC through November 2016 have included a progressive increase in the high voltage applied to the avalanche photodiode detector. LAC began <span class="hlt">lightning</span> survey observations in December 2016. It was confirmed that the operational high voltage was achieved and that the triggering system functions correctly. LAC <span class="hlt">lightning</span> search observations are planned to continue for several years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100040471','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100040471"><span>Triggered-<span class="hlt">Lightning</span> Interaction with a <span class="hlt">Lightning</span> Protective System: Current Distribution and Electromagnetic Environment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mata, C. T.; Rakov, V. A.; Mata, A. G.</p> <p>2010-01-01</p> <p>A new comprehensive <span class="hlt">lightning</span> instrumentation system has been designed for Launch Complex 39B (LC3913) at the Kennedy Space Center, Florida. This new instrumentation system includes the synchronized recording of six high-speed video cameras; currents through the nine downconductors of the new <span class="hlt">lightning</span> protection system for LC3913; four dH/dt, 3-axis measurement stations; and five dE/dt stations composed of two antennas each. A 20:1 scaled down model of the new <span class="hlt">Lightning</span> Protection System (LPS) of LC39B was built at the International Center for <span class="hlt">Lightning</span> Research and Testing, Camp Blanding, FL. This scaled down <span class="hlt">lightning</span> protection system was instrumented with the transient recorders, digitizers, and sensors to be used in the final instrumentation installation at LC3913. The instrumentation used at the ICLRT is also a scaled-down instrumentation of the LC39B instrumentation. The scaled-down LPS was subjected to seven direct <span class="hlt">lightning</span> strikes and six (four triggered and two natural nearby flashes) in 2010. The following measurements were acquired at the ICLRT: currents through the nine downconductors; two dl-/dt, 3-axis stations, one at the center of the LPS (underneath the catenary wires), and another 40 meters south from the center of the LPS; ten dE/dt stations, nine of them on the perimeter of the LPS and one at the center of the LPS (underneath the catenary wire system); and the incident current. Data from representative events are presented and analyzed in this paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NatCC...8..210F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NatCC...8..210F"><span>A projected decrease in <span class="hlt">lightning</span> under climate change</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Finney, Declan L.; Doherty, Ruth M.; Wild, Oliver; Stevenson, David S.; MacKenzie, Ian A.; Blyth, Alan M.</p> <p>2018-03-01</p> <p><span class="hlt">Lightning</span> strongly influences atmospheric chemistry1-3, and impacts the frequency of natural wildfires4. Most previous studies project an increase in global <span class="hlt">lightning</span> with climate change over the coming century1,5-7, but these typically use parameterizations of <span class="hlt">lightning</span> that neglect cloud ice fluxes, a component generally considered to be fundamental to thunderstorm charging8. As such, the response of <span class="hlt">lightning</span> to climate change is uncertain. Here, we compare <span class="hlt">lightning</span> projections for 2100 using two parameterizations: the widely used cloud-top height (CTH) approach9, and a new upward cloud ice flux (IFLUX) approach10 that overcomes previous limitations. In contrast to the previously reported global increase in <span class="hlt">lightning</span> based on CTH, we find a 15% decrease in total <span class="hlt">lightning</span> flash rate with IFLUX in 2100 under a strong global warming scenario. Differences are largest in the tropics, where most <span class="hlt">lightning</span> occurs, with implications for the estimation of future changes in tropospheric ozone and methane, as well as differences in their radiative forcings. These results suggest that <span class="hlt">lightning</span> schemes more closely related to cloud ice and microphysical processes are needed to robustly estimate future changes in <span class="hlt">lightning</span> and atmospheric composition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18814638','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18814638"><span>Beyond the basics: <span class="hlt">lightning</span>-strike injuries.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mistovich, Joseph J; Krost, William S; Limmer, Daniel D</p> <p>2008-03-01</p> <p>It is estimated that a <span class="hlt">lightning</span> flash occurs approximately 8 million times per day throughout the world. Most strikes are benign and cause little damage to property and physical structures; however, when <span class="hlt">lightning</span> strikes a person or group of people, it is a significant medical and potentially traumatic event that could lead to immediate death or permanent disability. By understanding some basic physics of <span class="hlt">lightning</span> and pathophysiology of injuries associated with <span class="hlt">lightning</span> strikes, EMS providers will be better prepared to identify assessment findings, anticipate complications and provide effective emergency care.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19980237715','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19980237715"><span><span class="hlt">Lightning</span> Radio Source Retrieval Using Advanced <span class="hlt">Lightning</span> Direction Finder (ALDF) Networks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William J.; Blakeslee, Richard J.; Bailey, J. C.</p> <p>1998-01-01</p> <p>A linear algebraic solution is provided for the problem of retrieving the location and time of occurrence of <span class="hlt">lightning</span> ground strikes from an Advanced <span class="hlt">Lightning</span> Direction Finder (ALDF) network. The ALDF network measures field strength, magnetic bearing and arrival time of <span class="hlt">lightning</span> radio emissions. Solutions for the plane (i.e., no Earth curvature) are provided that implement all of tile measurements mentioned above. Tests of the retrieval method are provided using computer-simulated data sets. We also introduce a quadratic planar solution that is useful when only three arrival time measurements are available. The algebra of the quadratic root results are examined in detail to clarify what portions of the analysis region lead to fundamental ambiguities in source location. Complex root results are shown to be associated with the presence of measurement errors when the <span class="hlt">lightning</span> source lies near an outer sensor baseline of the ALDF network. In the absence of measurement errors, quadratic root degeneracy (no source location ambiguity) is shown to exist exactly on the outer sensor baselines for arbitrary non-collinear network geometries. The accuracy of the quadratic planar method is tested with computer generated data sets. The results are generally better than those obtained from the three station linear planar method when bearing errors are about 2 deg. We also note some of the advantages and disadvantages of these methods over the nonlinear method of chi(sup 2) minimization employed by the National <span class="hlt">Lightning</span> Detection Network (NLDN) and discussed in Cummins et al.(1993, 1995, 1998).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=fitness&pg=4&id=EJ945983','ERIC'); return false;" href="https://eric.ed.gov/?q=fitness&pg=4&id=EJ945983"><span>Having a <span class="hlt">Ball</span> with Fitness <span class="hlt">Balls</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>McNulty, Betty</p> <p>2011-01-01</p> <p>Fitness programs can be greatly enhanced with the addition of fitness <span class="hlt">balls</span>. They are a fun, challenging, economical, and safe way to incorporate a cardiovascular, strength, and stretching program for all fitness levels in a physical education setting. The use of these <span class="hlt">balls</span> has become more popular during the last decade, and their benefits and…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMAE24A..03Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMAE24A..03Z"><span>Analysis and Modeling of Intense Oceanic <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zoghzoghy, F. G.; Cohen, M.; Said, R.; Lehtinen, N. G.; Inan, U.</p> <p>2014-12-01</p> <p>Recent studies using <span class="hlt">lightning</span> data from geo-location networks such as GLD360 suggest that <span class="hlt">lightning</span> strokes are more intense over the ocean than over land, even though they are less common [Said et al. 2013]. We present an investigation of the physical differences between oceanic and land <span class="hlt">lightning</span>. We have deployed a sensitive Low Frequency (1 MHz sampling rate) radio receiver system aboard the NOAA Ronald W. Brown research vessel and have collected thousands of <span class="hlt">lightning</span> waveforms close to deep oceanic <span class="hlt">lightning</span>. We analyze the captured waveforms, describe our modeling efforts, and summarize our findings. We model the ground wave (gw) portion of the <span class="hlt">lightning</span> sferics using a numerical method built on top of the Stanford Full Wave Method (FWM) [Lehtinen and Inan 2008]. The gwFWM technique accounts for propagation over a curved Earth with finite conductivity, and is used to simulate an arbitrary current profile along the <span class="hlt">lightning</span> channel. We conduct a sensitivity analysis and study the current profiles for land and for oceanic <span class="hlt">lightning</span>. We find that the effect of ground conductivity is minimal, and that stronger oceanic radio intensity does not result from shorter current rise-time or from faster return stroke propagation speed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140007287','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140007287"><span>Assessment of the Pseudo Geostationary <span class="hlt">Lightning</span> Mapper Products at the Spring Program and Summer Experiment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stano, Geoffrey T.; Calhoun, Kristin K.; Terborg, Amanda M.</p> <p>2014-01-01</p> <p>Since 2010, the de facto Geostationary <span class="hlt">Lightning</span> Mapper (GLM) demonstration product has been the Pseudo-Geostationary <span class="hlt">Lightning</span> Mapper (PGLM) product suite. Originally prepared for the Hazardous Weather Testbed's Spring Program (specifically the Experimental Warning Program) when only four ground-based <span class="hlt">lightning</span> mapping arrays were available, the effort now spans collaborations with several institutions and eight collaborative networks. For 2013, NASA's Short-term Prediction Research and Transition (SPoRT) Center and NOAA's National Severe Storms <span class="hlt">Laboratory</span> have worked to collaborate with each network to obtain data in real-time. This has gone into producing the SPoRT variant of the PGLM that was demonstrated in AWIPS II for the 2013 Spring Program. Alongside the PGLM products, the SPoRT / Meteorological Development <span class="hlt">Laboratory</span>'s total <span class="hlt">lightning</span> tracking tool also was evaluated to assess not just another visualization of future GLM data but how to best extract more information while in the operational environment. Specifically, this tool addressed the leading request by forecasters during evaluations; provide a time series trend of total <span class="hlt">lightning</span> in real-time. In addition to the Spring Program, SPoRT is providing the PGLM "mosaic" to the Aviation Weather Center (AWC) and Storm Prediction Center. This is the same as what is used at the Hazardous Weather Testbed, but combines all available networks into one display for use at the national centers. This year, the mosaic was evaluated during the AWC's Summer Experiment. An important distinction between this and the Spring Program is that the Summer Experiment focuses on the national center perspective and not at the local forecast office level. Specifically, the Summer Experiment focuses on aviation needs and concerns and brings together operational forecaster, developers, and FAA representatives. This presentation will focus on the evaluation of SPoRT's pseudo-GLM products in these separate test beds. The emphasis</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.6487I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.6487I"><span>Nowcasting of <span class="hlt">Lightning</span>-Related Accidents in Africa</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ihrlich, Laura; Price, Colin</p> <p>2016-04-01</p> <p>Tropical Africa is the world capital of thunderstorm activity with the highest density of strikes per square kilometer per year. As a result it is also the continent with perhaps the highest casualties and injuries from direct <span class="hlt">lightning</span> strikes. This region of the globe also has little <span class="hlt">lightning</span> protection of rural homes and schools, while many casualties occur during outdoor activities (e.g. farming, fishing, sports, etc.) In this study we investigated two <span class="hlt">lightning</span>-caused accidents that got wide press coverage: A <span class="hlt">lightning</span> strike to a Cheetah Center in Namibia which caused a huge fire and great destruction (16 October 2013), and a plane crash in Mali where 116 people died (24 July 2014). Using data from the World Wide <span class="hlt">Lightning</span> Location Network (WWLLN) we show that the <span class="hlt">lightning</span> data alone can provide important early warning information that can be used to reduce risks and damages and loss of life from <span class="hlt">lightning</span> strikes. We have developed a now-casting scheme that allows for early warnings across Africa with a relatively low false alarm rate. To verify the accuracy of our now-cast, we have performed some statistical analysis showing relatively high skill at providing early warnings (lead time of a few hours) based on <span class="hlt">lightning</span> alone. Furthermore, our analysis can be used in forensic meteorology for determining if such accidents are caused by <span class="hlt">lightning</span> strikes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.6604N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.6604N"><span>Spatio-temporal activity of <span class="hlt">lightnings</span> over Greece</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nastos, P. T.; Matsangouras, I. T.; Chronis, T. G.</p> <p>2012-04-01</p> <p>Extreme precipitation events are always associated with convective weather conditions driving to intense <span class="hlt">lightning</span> activity: Cloud to Ground (CG), Ground to Cloud (GC) and Cloud to Cloud (CC). Thus, the study of <span class="hlt">lightnings</span>, which typically occur during thunderstorms, gives evidence of the spatio-temporal variability of intense precipitation. <span class="hlt">Lightning</span> is a natural phenomenon in the atmosphere, being a major cause of storm related with deaths and main trigger of forest fires during dry season. <span class="hlt">Lightning</span> affects the many electrochemical systems of the body causing nerve damage, memory loss, personality change, and emotional problems. Besides, among the various nitrogen oxides sources, the contribution from <span class="hlt">lightning</span> likely represents the largest uncertainty. An operational <span class="hlt">lightning</span> detection network (LDN) has been established since 2007 by HNMS, consisting of eight time-of-arrival sensors (TOA), spatially distributed across Greek territory. In this study, the spatial and temporal variability of recorded <span class="hlt">lightnings</span> (CG, GC and CC) are analyzed over Greece, during the period from January 14, 2008 to December 31, 2009, for the first time. The data for retrieving the location and time-of-occurrence of <span class="hlt">lightning</span> were acquired from Hellenic National Meteorological Service (HNMS). In addition to the analysis of spatio-temporal activity over Greece, the HNMS-LDN characteristics are also presented. The results of the performed analysis reveal the specific geographical sub-regions associated with <span class="hlt">lightnings</span> incidence. <span class="hlt">Lightning</span> activity occurs mainly during the autumn season, followed by summer and spring. Higher frequencies of flashes appear over Ionian and Aegean Sea than over land during winter period against continental mountainous regions during summer period.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/48980','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/48980"><span><span class="hlt">Lightning</span> fire research in the Rocky Mountains</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>J. S. Barrows</p> <p>1954-01-01</p> <p><span class="hlt">Lightning</span> is the major cause of fires in Rocky Mountain forests. The <span class="hlt">lightning</span> fire problem is the prime target of a broad research program now known as Project Skyfire. KEYWORDS: <span class="hlt">lightning</span>, fire research</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PrAeS..64....1G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PrAeS..64....1G"><span><span class="hlt">Lightning</span> strike protection of composites</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gagné, Martin; Therriault, Daniel</p> <p>2014-01-01</p> <p>Aircraft structures are being redesigned to use fiber-reinforced composites mainly due to their high specific stiffness and strength. One of the main drawbacks from changing from electrically conductive metals to insulating or semi-conducting composites is the higher vulnerability of the aircraft to <span class="hlt">lightning</span> strike damage. The current protection approach consists of bonding a metal mesh to the surface of the composite structure, but this weight increase negatively impact the fuel efficiency. This review paper presents an overview of the <span class="hlt">lightning</span> strike problematic, the regulations, the <span class="hlt">lightning</span> damage to composite, the current protection solutions and other material or technology alternatives. Advanced materials such as polymer-based nanocomposites and carbon nanotube buckypapers are promising candidates for lightweight <span class="hlt">lightning</span> strike protection technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMAE12A..02F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMAE12A..02F"><span>Infrasound from <span class="hlt">lightning</span> measured in Ivory Coast</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farges, T.; Matoza, R. S.</p> <p>2011-12-01</p> <p>It is well established that more than 2,000 thunderstorms occur continuously around the world and that about 45 <span class="hlt">lightning</span> flashes are produced per second over the globe. More than two thirds (42) of the infrasound stations of the International Monitoring System (IMS) of the CTBTO (Comprehensive nuclear Test Ban Treaty Organisation) are now certified and routinely measure signals due to natural activity (e.g., airflow over mountains, aurora, microbaroms, surf, volcanoes, severe weather including <span class="hlt">lightning</span> flashes, ...). Some of the IMS stations are located where worldwide <span class="hlt">lightning</span> detection networks (e.g. WWLLN) have a weak detection capability but <span class="hlt">lightning</span> activity is high (e.g. Africa, South America). These infrasound stations are well localised to study <span class="hlt">lightning</span> flash activity and its disparity, which is a good proxy for global warming. Progress in infrasound array data processing over the past ten years makes such <span class="hlt">lightning</span> studies possible. For example, Farges and Blanc (2010) show clearly that it is possible to measure <span class="hlt">lightning</span> infrasound from thunderstorms within a range of distances from the infrasound station. Infrasound from <span class="hlt">lightning</span> can be detected when the thunderstorm is within about 75 km from the station. The motion of the squall zone is very well measured inside this zone. Up to 25% of <span class="hlt">lightning</span> flashes can be detected with this technique, giving better results locally than worldwide <span class="hlt">lightning</span> detection networks. An IMS infrasound station has been installed in Ivory Coast for 8 years. The optical space-based instrument OTD measured a rate of 10-20 flashes/km^2/year in that country and showed strong seasonal variations (Christian et al., 2003). Ivory Coast is therefore a good place to study infrasound data associated with <span class="hlt">lightning</span> activity and its temporal variation. First statistical results will be presented in this paper based on 3 years of data (2005-2008).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA093128','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA093128"><span>Corona from Ice, Thunderstorm Electrification and <span class="hlt">Lightning</span> Suppression.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1980-11-01</p> <p>rates of droplets highly charged by interaction with corona streamers. <span class="hlt">Laboratory</span> and theoretical studies have been performed in an effort to explore in...CORONA FROM ICE, THUNDERSTORM ELECTRIFICATION Final AND <span class="hlt">LIGHTNING</span> SUPPRESSION 1 Sep 77 to 31 Aug 80 6. Performing Org. Report Number 7. Author(s) 8...Contract or Grant Number J. Latham AFOSR-77-3429 O"o 9. Performing Organization Name and Address 10. Program Element, Project, Task Physics Department</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140017446','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140017446"><span>First Cloud-to-Ground <span class="hlt">Lightning</span> Timing Study</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Huddleston, Lisa L.</p> <p>2013-01-01</p> <p>NASA's LSP, GSDO and other programs use the probability of cloud-to-ground (CG) <span class="hlt">lightning</span> occurrence issued by the 45th Weather Squadron (45 WS) in their daily and weekly <span class="hlt">lightning</span> probability forecasts. These organizations use this information when planning potentially hazardous outdoor activities, such as working with fuels, or rolling a vehicle to a launch pad, or whenever personnel will work outside and would be at-risk from <span class="hlt">lightning</span>. These organizations would benefit greatly if the 45 WS could provide more accurate timing of the first CG <span class="hlt">lightning</span> strike of the day. The Applied Meteorology Unit (AMU) has made significant improvements in forecasting the probability of <span class="hlt">lightning</span> for the day, but forecasting the time of the first CG <span class="hlt">lightning</span> with confidence has remained a challenge. To address this issue, the 45 WS requested the AMU to determine if flow regimes, wind speed categories, or a combination of the two could be used to forecast the timing of the first strike of the day in the Kennedy Space Center (KSC)/Cape Canaveral Air Force Station (CCAFS) <span class="hlt">lightning</span> warning circles. The data was stratified by various sea breeze flow regimes and speed categories in the surface to 5,000-ft layer. The surface to 5,000-ft layer was selected since that is the layer the 45 WS uses to predict the behavior of sea breeze fronts, which are the dominant influence on the occurrence of first <span class="hlt">lightning</span> in Florida during the warm season. Due to small data sample sizes after stratification, the AMU could not determine a statistical relationship between flow regimes or speed categories and the time of the first CG strike.. As expected, although the amount and timing of <span class="hlt">lightning</span> activity varies by time of day based on the flow regimes and speed categories, there are extended tails of low <span class="hlt">lightning</span> activity making it difficult to specify times when the threat of the first <span class="hlt">lightning</span> flash can be avoided. However, the AMU developed a graphical user interface with input from the 45 WS</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.1285F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.1285F"><span>Infrasound from <span class="hlt">lightning</span> measured in Ivory Coast</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farges, T.; Millet, C.; Matoza, R. S.</p> <p>2012-04-01</p> <p>It is well established that more than 2,000 thunderstorms occur continuously around the world and that about 45 <span class="hlt">lightning</span> flashes are produced per second over the globe. More than two thirds (42) of the infrasound stations of the International Monitoring System (IMS) of the CTBTO (Comprehensive nuclear Test Ban Treaty Organisation) are now certified and routinely measure signals due to natural activity (e.g., airflow over mountains, aurora, microbaroms, surf, volcanoes, severe weather including <span class="hlt">lightning</span> flashes, …). Some of the IMS stations are located where worldwide <span class="hlt">lightning</span> detection networks (e.g. WWLLN) have a weak detection capability but <span class="hlt">lightning</span> activity is high (e.g. Africa, South America). These infrasound stations are well localised to study <span class="hlt">lightning</span> flash activity and its disparity, which is a good proxy for global warming. Progress in infrasound array data processing over the past ten years makes such <span class="hlt">lightning</span> studies possible. For example, Farges and Blanc (2010) show clearly that it is possible to measure <span class="hlt">lightning</span> infrasound from thunderstorms within a range of distances from the infrasound station. Infrasound from <span class="hlt">lightning</span> can be detected when the thunderstorm is within about 75 km from the station. The motion of the squall zone is very well measured inside this zone. Up to 25% of <span class="hlt">lightning</span> flashes can be detected with this technique, giving better results locally than worldwide <span class="hlt">lightning</span> detection networks. An IMS infrasound station has been installed in Ivory Coast for 9 years. The <span class="hlt">lightning</span> rate of this region is 10-20 flashes/km2/year from space-based instrument OTD (Christian et al., 2003). Ivory Coast is therefore a good place to study infrasound data associated with <span class="hlt">lightning</span> activity and its temporal variation. First statistical results will be presented in this paper based on 4 years of data (2005-2009). For short <span class="hlt">lightning</span> distances (less than 20 km), up to 60 % of <span class="hlt">lightning</span> detected by WWLLN has been one-to-one correlated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27466230','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27466230"><span>A Fossilized Energy Distribution of <span class="hlt">Lightning</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pasek, Matthew A; Hurst, Marc</p> <p>2016-07-28</p> <p>When <span class="hlt">lightning</span> strikes soil, it may generate a cylindrical tube of glass known as a fulgurite. The morphology of a fulgurite is ultimately a consequence of the energy of the <span class="hlt">lightning</span> strike that formed it, and hence fulgurites may be useful in elucidating the energy distribution frequency of cloud-to-ground <span class="hlt">lightning</span>. Fulgurites from sand mines in Polk County, Florida, USA were collected and analyzed to determine morphologic properties. Here we show that the energy per unit length of <span class="hlt">lightning</span> strikes within quartz sand has a geometric mean of ~1.0 MJ/m, and that the distribution is lognormal with respect to energy per length and frequency. Energy per length is determined from fulgurites as a function of diameter, and frequency is determined both by cumulative number and by cumulative length. This distribution parallels those determined for a number of <span class="hlt">lightning</span> parameters measured in actual atmospheric discharge events, such as charge transferred, voltage, and action integral. This methodology suggests a potential useful pathway for elucidating <span class="hlt">lightning</span> energy and damage potential of strikes.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4964350','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4964350"><span>A Fossilized Energy Distribution of <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Pasek, Matthew A.; Hurst, Marc</p> <p>2016-01-01</p> <p>When <span class="hlt">lightning</span> strikes soil, it may generate a cylindrical tube of glass known as a fulgurite. The morphology of a fulgurite is ultimately a consequence of the energy of the <span class="hlt">lightning</span> strike that formed it, and hence fulgurites may be useful in elucidating the energy distribution frequency of cloud-to-ground <span class="hlt">lightning</span>. Fulgurites from sand mines in Polk County, Florida, USA were collected and analyzed to determine morphologic properties. Here we show that the energy per unit length of <span class="hlt">lightning</span> strikes within quartz sand has a geometric mean of ~1.0 MJ/m, and that the distribution is lognormal with respect to energy per length and frequency. Energy per length is determined from fulgurites as a function of diameter, and frequency is determined both by cumulative number and by cumulative length. This distribution parallels those determined for a number of <span class="hlt">lightning</span> parameters measured in actual atmospheric discharge events, such as charge transferred, voltage, and action integral. This methodology suggests a potential useful pathway for elucidating <span class="hlt">lightning</span> energy and damage potential of strikes. PMID:27466230</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29303164','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29303164"><span>Automated Storm Tracking and the <span class="hlt">Lightning</span> Jump Algorithm Using GOES-R Geostationary <span class="hlt">Lightning</span> Mapper (GLM) Proxy Data.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schultz, Elise V; Schultz, Christopher J; Carey, Lawrence D; Cecil, Daniel J; Bateman, Monte</p> <p>2016-01-01</p> <p>This study develops a fully automated <span class="hlt">lightning</span> jump system encompassing objective storm tracking, Geostationary <span class="hlt">Lightning</span> Mapper proxy data, and the <span class="hlt">lightning</span> jump algorithm (LJA), which are important elements in the transition of the LJA concept from a research to an operational based algorithm. Storm cluster tracking is based on a product created from the combination of a radar parameter (vertically integrated liquid, VIL), and <span class="hlt">lightning</span> information (flash rate density). Evaluations showed that the spatial scale of tracked features or storm clusters had a large impact on the <span class="hlt">lightning</span> jump system performance, where increasing spatial scale size resulted in decreased dynamic range of the system's performance. This framework will also serve as a means to refine the LJA itself to enhance its operational applicability. Parameters within the system are isolated and the system's performance is evaluated with adjustments to parameter sensitivity. The system's performance is evaluated using the probability of detection (POD) and false alarm ratio (FAR) statistics. Of the algorithm parameters tested, sigma-level (metric of <span class="hlt">lightning</span> jump strength) and flash rate threshold influenced the system's performance the most. Finally, verification methodologies are investigated. It is discovered that minor changes in verification methodology can dramatically impact the evaluation of the <span class="hlt">lightning</span> jump system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160009780','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160009780"><span>Automated Storm Tracking and the <span class="hlt">Lightning</span> Jump Algorithm Using GOES-R Geostationary <span class="hlt">Lightning</span> Mapper (GLM) Proxy Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schultz, Elise; Schultz, Christopher Joseph; Carey, Lawrence D.; Cecil, Daniel J.; Bateman, Monte</p> <p>2016-01-01</p> <p>This study develops a fully automated <span class="hlt">lightning</span> jump system encompassing objective storm tracking, Geostationary <span class="hlt">Lightning</span> Mapper proxy data, and the <span class="hlt">lightning</span> jump algorithm (LJA), which are important elements in the transition of the LJA concept from a research to an operational based algorithm. Storm cluster tracking is based on a product created from the combination of a radar parameter (vertically integrated liquid, VIL), and <span class="hlt">lightning</span> information (flash rate density). Evaluations showed that the spatial scale of tracked features or storm clusters had a large impact on the <span class="hlt">lightning</span> jump system performance, where increasing spatial scale size resulted in decreased dynamic range of the system's performance. This framework will also serve as a means to refine the LJA itself to enhance its operational applicability. Parameters within the system are isolated and the system's performance is evaluated with adjustments to parameter sensitivity. The system's performance is evaluated using the probability of detection (POD) and false alarm ratio (FAR) statistics. Of the algorithm parameters tested, sigma-level (metric of <span class="hlt">lightning</span> jump strength) and flash rate threshold influenced the system's performance the most. Finally, verification methodologies are investigated. It is discovered that minor changes in verification methodology can dramatically impact the evaluation of the <span class="hlt">lightning</span> jump system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5749929','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5749929"><span>Automated Storm Tracking and the <span class="hlt">Lightning</span> Jump Algorithm Using GOES-R Geostationary <span class="hlt">Lightning</span> Mapper (GLM) Proxy Data</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>SCHULTZ, ELISE V.; SCHULTZ, CHRISTOPHER J.; CAREY, LAWRENCE D.; CECIL, DANIEL J.; BATEMAN, MONTE</p> <p>2017-01-01</p> <p>This study develops a fully automated <span class="hlt">lightning</span> jump system encompassing objective storm tracking, Geostationary <span class="hlt">Lightning</span> Mapper proxy data, and the <span class="hlt">lightning</span> jump algorithm (LJA), which are important elements in the transition of the LJA concept from a research to an operational based algorithm. Storm cluster tracking is based on a product created from the combination of a radar parameter (vertically integrated liquid, VIL), and <span class="hlt">lightning</span> information (flash rate density). Evaluations showed that the spatial scale of tracked features or storm clusters had a large impact on the <span class="hlt">lightning</span> jump system performance, where increasing spatial scale size resulted in decreased dynamic range of the system’s performance. This framework will also serve as a means to refine the LJA itself to enhance its operational applicability. Parameters within the system are isolated and the system’s performance is evaluated with adjustments to parameter sensitivity. The system’s performance is evaluated using the probability of detection (POD) and false alarm ratio (FAR) statistics. Of the algorithm parameters tested, sigma-level (metric of <span class="hlt">lightning</span> jump strength) and flash rate threshold influenced the system’s performance the most. Finally, verification methodologies are investigated. It is discovered that minor changes in verification methodology can dramatically impact the evaluation of the <span class="hlt">lightning</span> jump system. PMID:29303164</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....3339P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....3339P"><span>Positive <span class="hlt">lightning</span> and severe weather</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Price, C.; Murphy, B.</p> <p>2003-04-01</p> <p>In recent years researchers have noticed that severe weather (tornados, hail and damaging winds) are closely related to the amount of positive <span class="hlt">lightning</span> occurring in thunderstorms. On 4 July 1999, a severe derecho (wind storm) caused extensive damage to forested regions along the United States/Canada border, west of Lake Superior. There were 665,000 acres of forest destroyed in the Boundary Waters Canoe Area Wilderness (BWCAW) in Minnesota and Quetico Provincial Park in Canada, with approximately 12.5 million trees blown down. This storm resulted in additional severe weather before and after the occurrence of the derecho, with continuous cloud-to-ground (CG) <span class="hlt">lightning</span> occurring for more than 34 hours during its path across North America. At the time of the derecho the percentage of positive cloud-to-ground (+CG) <span class="hlt">lightning</span> measured by the Canadian <span class="hlt">Lightning</span> Detection Network (CLDN) was greater than 70% for more than three hours, with peak values reaching 97% positive CG <span class="hlt">lightning</span>. Such high ratios of +CG are rare, and may be useful indicators for short-term forecasts of severe weather.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUSMAE11A..03M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUSMAE11A..03M"><span>Modern Protection Against <span class="hlt">Lightning</span> Strikes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moore, C.</p> <p>2005-05-01</p> <p>The application of science to provide protection against <span class="hlt">lightning</span> strikes began around 1750 when Benjamin Franklin who invented the <span class="hlt">lightning</span> rod in an effort to discharge thunderclouds. Instead of preventing <span class="hlt">lightning</span> as he expected, his rods have been quite successful as strike receptors, intercepting cloud-to ground discharges and conducting them to Earth without damage to the structures on which they are mounted. In the years since Franklin's invention there has been little attention paid to the rod configuration that best serves as a strike receptor but Franklin's original ideas continue to be rediscovered and promoted. Recent measurements of the responses of variously configured rods to nearby strikes indicate that sharp-tipped rods are not the optimum configuration to serve as strike receptors since the ionization of the air around their tips limits the strength of the local electric fields created by an approaching <span class="hlt">lightning</span> leader. In these experiments, fourteen blunt-tipped rods exposed in strike-reception competitions with nearby sharp-tipped rods were struck by <span class="hlt">lightning</span> but none of the sharp-tipped rods were struck.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AtmRe.172....1M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AtmRe.172....1M"><span>The verification of <span class="hlt">lightning</span> location accuracy in Finland deduced from <span class="hlt">lightning</span> strikes to trees</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mäkelä, Antti; Mäkelä, Jakke; Haapalainen, Jussi; Porjo, Niko</p> <p>2016-05-01</p> <p>We present a new method to determine the ground truth and accuracy of <span class="hlt">lightning</span> location systems (LLS), using natural <span class="hlt">lightning</span> strikes to trees. Observations of strikes to trees are being collected with a Web-based survey tool at the Finnish Meteorological Institute. Since the Finnish thunderstorms tend to have on average a low flash rate, it is often possible to identify from the LLS data unambiguously the stroke that caused damage to a given tree. The coordinates of the tree are then the ground truth for that stroke. The technique has clear advantages over other methods used to determine the ground truth. Instrumented towers and rocket launches measure upward-propagating <span class="hlt">lightning</span>. Video and audio records, even with triangulation, are rarely capable of high accuracy. We present data for 36 quality-controlled tree strikes in the years 2007-2008. We show that the average inaccuracy of the <span class="hlt">lightning</span> location network for that period was 600 m. In addition, we show that the 50% confidence ellipse calculated by the <span class="hlt">lightning</span> location network and used operationally for describing the location accuracy is physically meaningful: half of all the strikes were located within the uncertainty ellipse of the nearest recorded stroke. Using tree strike data thus allows not only the accuracy of the LLS to be estimated but also the reliability of the uncertainty ellipse. To our knowledge, this method has not been attempted before for natural <span class="hlt">lightning</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1713577H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1713577H"><span>Severe weather detection by using Japanese Total <span class="hlt">Lightning</span> Network</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hobara, Yasuhide; Ishii, Hayato; Kumagai, Yuri; Liu, Charlie; Heckman, Stan; Price, Colin</p> <p>2015-04-01</p> <p>In this paper we demonstrate the preliminary results from the first Japanese Total <span class="hlt">Lightning</span> Network. The University of Electro-Communications (UEC) recently deployed Earth Networks Total <span class="hlt">Lightning</span> System over Japan to conduct various <span class="hlt">lightning</span> research projects. Here we analyzed the total <span class="hlt">lightning</span> data in relation with 10 severe events such as gust fronts and tornadoes occurred in 2014 in mainland Japan. For the analysis of these events, <span class="hlt">lightning</span> jump algorithm was used to identify the increase of the flash rate in prior to the severe weather events. We found that <span class="hlt">lightning</span> jumps associated with significant increasing <span class="hlt">lightning</span> activities for total <span class="hlt">lightning</span> and IC clearly indicate the severe weather occurrence than those for CGs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23478564','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23478564"><span><span class="hlt">Lightning</span> injuries in sports and recreation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Thomson, Eric M; Howard, Thomas M</p> <p>2013-01-01</p> <p>The powers of <span class="hlt">lightning</span> have been worshiped and feared by all known human cultures. While the chance of being struck by <span class="hlt">lightning</span> is statistically very low, that risk becomes much greater in those who frequently work or play outdoors. Over the past 2 yr, there have been nearly 50 <span class="hlt">lightning</span>-related deaths reported within the United States, with a majority of them associated with outdoor recreational activities. Recent publications primarily have been case studies, review articles, and a discussion of a sixth method of injury. The challenge in reducing <span class="hlt">lightning</span>-related injuries in organized sports has been addressed well by both the National Athletic Trainers' Association and the National Collegiate Athletic Association in their guidelines on <span class="hlt">lightning</span> safety. Challenges remain in educating the general population involved in recreational outdoor activities that do not fall under the guidelines of organized sports.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008GeoRL..3515802A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008GeoRL..3515802A"><span>Characterization of infrasound from <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Assink, J. D.; Evers, L. G.; Holleman, I.; Paulssen, H.</p> <p>2008-08-01</p> <p>During thunderstorm activity in the Netherlands, electromagnetic and infrasonic signals are emitted due to the process of <span class="hlt">lightning</span> and thunder. It is shown that correlating infrasound detections with results from a electromagnetic <span class="hlt">lightning</span> detection network is successful up to distances of 50 km from the infrasound array. Infrasound recordings clearly show blastwave characteristics which can be related to cloud-ground discharges, with a dominant frequency between 1-5 Hz. Amplitude measurements of CG discharges can partly be explained by the beam pattern of a line source with a dominant frequency of 3.9 Hz, up to a distance of 20 km. The ability to measure <span class="hlt">lightning</span> activity with infrasound arrays has both positive and negative implications for CTBT verification purposes. As a scientific application, <span class="hlt">lightning</span> studies can benefit from the worldwide infrasound verification system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970024904','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970024904"><span><span class="hlt">Lightning</span> Effects in the Payload Changeout Room</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thomas, Garland L.; Fisher, Franklin A.; Collier, Richard S.; Medelius, Pedro J.</p> <p>1997-01-01</p> <p>Analytical and empirical studies have been performed to provide better understanding of the electromagnetic environment inside the Payload Changeout Room and Orbiter payload bay resulting from <span class="hlt">lightning</span> strikes to the launch pad <span class="hlt">lightning</span> protection system. The analytical studies consisted of physical and mathematical modeling of the pad structure and the Payload Changeout Room. Empirical testing was performed using a <span class="hlt">lightning</span> simulator to simulate controlled (8 kA) <span class="hlt">lightning</span> strikes to the catenary wire <span class="hlt">lightning</span> protection system. In addition to the analyses and testing listed above, an analysis of the configuration with the vehicle present was conducted, in lieu of testing, by the Finite Difference, Time Domain method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/362646-grounding-lightning-protection-volume','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/362646-grounding-lightning-protection-volume"><span>Grounding and <span class="hlt">lightning</span> protection. Volume 5</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Robinson, M.D.</p> <p>1987-12-31</p> <p>Grounding systems protect personnel and equipment by isolating faulted systems and dissipating transient currents. <span class="hlt">Lightning</span> protection systems minimize the possible consequences of a direct strike by <span class="hlt">lightning</span>. This volume focuses on design requirements of the grounding system and on present-day concepts used in the design of <span class="hlt">lightning</span> protection systems. Various types of grounding designs are presented, and their advantages and disadvantages discussed. Safety, of course, is the primary concern of any grounding system. Methods are shown for grounding the non-current-carrying parts of electrical equipment to reduce shock hazards to personnel. <span class="hlt">Lightning</span> protection systems are installed on tall structures (such asmore » chimneys and cooling towers) to minimize the possibility of structural damage caused by direct <span class="hlt">lightning</span> strokes. These strokes may carry currents of 200,000 A or more. The volume examines the formation and characteristics of <span class="hlt">lightning</span> strokes and the way stroke characteristics influence the design of <span class="hlt">lightning</span> protection systems. Because a large portion of the grounding system is buried in soil or concrete, it is not readily accessible for inspection or repair after its installation. The volume details the careful selection and sizing of materials needed to ensure a long, maintenance-free life for the system. Industry standards and procedures for testing the adequacy of the grounding system are also discussed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUSMSA54A..02K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUSMSA54A..02K"><span><span class="hlt">Laboratory</span> Experiments of Helicity or Vortex Generation in an Electric Quadrupole: Simulation of Tonadoes with and without <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kikuchi, H.</p> <p>2007-05-01</p> <p><span class="hlt">Laboratory</span> Experiments of Helicity or Vortex Generation in an Electric Quadrupole: Simulation of Tornadoes with and without <span class="hlt">Lightning</span> H. Kikuchi Institute for Environmental Electromagnetics 3-8-18, Komagome, Toshima-ku, Tokyo 170, Japan e-mail: hkikuchi@mars.dti.ne.jp Abstract Usually the source-origins of helicity or vortex generation have been considered to be thermohydrodynamic in the hydrodynamic (HD) regime and/or magnetohydrodynamic in the magnetohydrodynamic (MHD) regime. It has been shown, however, by the present author that an electric quadrupole is also capable for helicity or vortex generation and a new electric helic- ity defined as hE= v·E (v: flow velocity; E: electric field) has been introduced. Accordingly, we have now three kinds of helicity, namely fluid, magnetic, and electric helicity. In many cases of atmospheric and space electricity phenomena in nature, electric helicity or vortex generation of electric origin is involved as typically seen in tornadic thunderstorms. Conventional theory of tornadoes, however, space- charge and electric fields have never been considered properly so far, surprisingly in spite of their effects of significance, because of no theorv for such cases, although those effects have been recognized implicitly by field experiments. This paper fills up these demands by newly introducing the concept of 'Electric Helicity' based on 'Electrohydrodynamics' (EHD) established and developed over the last more than two decades and such a whole theory is applied to tornadioes with and without <span class="hlt">lightning</span>. Further, experimental evidence of this theory is presented for the first time by using a 'universal electric-cusp type plasma reactor' designed more than a decade ago [1]. This device is composed of two positive and negative electrodes of lead spheres 1.5 cm in diameter suspended 2~5 cm above a copper plane on which a semispherical lead 1.25 cm in diameter or its modified object is placed. A whole setup is arranged in a wooden box</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-88_DarkLightning.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-88_DarkLightning.html"><span>ScienceCast 88: Dark <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2013-01-07</p> <p>Researchers studying thunderstorms have made a surprising discovery: The <span class="hlt">lightning</span> we see with our eyes has a dark competitor that discharges storm clouds and flings antimatter into space. Scientists are scrambling to understand "dark <span class="hlt">lightning</span>."</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70044899','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70044899"><span><span class="hlt">Ball</span> clay</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Virta, R.L.</p> <p>2011-01-01</p> <p>The article discusses the latest developments in the global <span class="hlt">ball</span> clay mining industry, particularly in the U.S., as of June 2011. It cites several firms that are involved in <span class="hlt">ball</span> clay mining in the U.S., including HC Spins Clay Co. Inc., the Imerys Group and Old Hickory Clay Co. Among the products made from <span class="hlt">ball</span> clay are ceramic tiles, sanitaryware, as well as fillers, extenders and binders.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AtmRe.203..164H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AtmRe.203..164H"><span>Cloud-to-ground <span class="hlt">lightning</span> activity in Colombia: A 14-year study using <span class="hlt">lightning</span> location system data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Herrera, J.; Younes, C.; Porras, L.</p> <p>2018-05-01</p> <p>This paper presents the analysis of 14 years of cloud-to-ground <span class="hlt">lightning</span> activity observation in Colombia using <span class="hlt">lightning</span> location systems (LLS) data. The first Colombian LLS operated from 1997 to 2001. After a few years, this system was upgraded and a new LLS has been operating since 2007. Data obtained from these two systems was analyzed in order to obtain <span class="hlt">lightning</span> parameters used in designing <span class="hlt">lightning</span> protection systems. The flash detection efficiency was estimated using average peak current maps and some theoretical results previously published. <span class="hlt">Lightning</span> flash multiplicity was evaluated using a stroke grouping algorithm resulting in average values of about 1.0 and 1.6 for positive and negative flashes respectively and for both LLS. The time variation of this parameter changes slightly for the years considered in this study. The first stroke peak current for negative and positive flashes shows median values close to 29 kA and 17 kA respectively for both networks showing a great dependence on the flash detection efficiency. The average percentage of negative and positive flashes shows a 74.04% and 25.95% of occurrence respectively. The daily variation shows a peak between 23 and 02 h. The monthly variation of this parameter exhibits a bimodal behavior typical of the regions located near The Equator. The <span class="hlt">lightning</span> flash density was obtained dividing the study area in 3 × 3 km cells and resulting in maximum average values of 25 and 35 flashes km- 2 year- 1 for each network respectively. A comparison of these results with global <span class="hlt">lightning</span> activity hotspots was performed showing good correlation. Besides, the <span class="hlt">lightning</span> flash density variation with altitude shows an inverse relation between these two variables.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3990883','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3990883"><span><span class="hlt">Ball</span> Machine Usage in Tennis: Movement Initiation and Swing Timing While Returning <span class="hlt">Balls</span> from a <span class="hlt">Ball</span> Machine and from a Real Server</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Carboch, Jan; Süss, Vladimir; Kocib, Tomas</p> <p>2014-01-01</p> <p>Practicing with the use of a <span class="hlt">ball</span> machine could handicap a player compared to playing against an actual opponent. Recent studies have shown some differences in swing timing and movement coordination, when a player faces a <span class="hlt">ball</span> projection machine as opposed to a human opponent. We focused on the time of movement initiation and on stroke timing during returning tennis serves (simulated by a <span class="hlt">ball</span> machine or by a real server). Receivers’ movements were measured on a tennis court. In spite of using a serving <span class="hlt">ball</span> speed from 90 kph to 135 kph, results showed significant differences in movement initiation and backswing duration between serves received from a <span class="hlt">ball</span> machine and serves received from a real server. Players had shorter movement initiation when they faced a <span class="hlt">ball</span> machine. Backswing duration was longer for the group using a <span class="hlt">ball</span> machine. That demonstrates different movement timing of tennis returns when players face a <span class="hlt">ball</span> machine. Use of <span class="hlt">ball</span> machines in tennis practice should be limited as it may disrupt stroke timing. Key points Players have shorter initial move time when they are facing the <span class="hlt">ball</span> machine. Using the <span class="hlt">ball</span> machine results in different swing timing and movement coordination. The use of the <span class="hlt">ball</span> machine should be limited. PMID:24790483</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24790483','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24790483"><span><span class="hlt">Ball</span> machine usage in tennis: movement initiation and swing timing while returning <span class="hlt">balls</span> from a <span class="hlt">ball</span> machine and from a real server.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Carboch, Jan; Süss, Vladimir; Kocib, Tomas</p> <p>2014-05-01</p> <p>Practicing with the use of a <span class="hlt">ball</span> machine could handicap a player compared to playing against an actual opponent. Recent studies have shown some differences in swing timing and movement coordination, when a player faces a <span class="hlt">ball</span> projection machine as opposed to a human opponent. We focused on the time of movement initiation and on stroke timing during returning tennis serves (simulated by a <span class="hlt">ball</span> machine or by a real server). Receivers' movements were measured on a tennis court. In spite of using a serving <span class="hlt">ball</span> speed from 90 kph to 135 kph, results showed significant differences in movement initiation and backswing duration between serves received from a <span class="hlt">ball</span> machine and serves received from a real server. Players had shorter movement initiation when they faced a <span class="hlt">ball</span> machine. Backswing duration was longer for the group using a <span class="hlt">ball</span> machine. That demonstrates different movement timing of tennis returns when players face a <span class="hlt">ball</span> machine. Use of <span class="hlt">ball</span> machines in tennis practice should be limited as it may disrupt stroke timing. Key pointsPlayers have shorter initial move time when they are facing the <span class="hlt">ball</span> machine.Using the <span class="hlt">ball</span> machine results in different swing timing and movement coordination.The use of the <span class="hlt">ball</span> machine should be limited.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.2128L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.2128L"><span>Nowcasting and forecasting of <span class="hlt">lightning</span> activity: the Talos project.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lagouvardos, Kostas; Kotroni, Vassiliki; Kazadzis, Stelios; Giannaros, Theodore; Karagiannidis, Athanassios; Galanaki, Elissavet; Proestakis, Emmanouil</p> <p>2015-04-01</p> <p>Thunder And <span class="hlt">Lightning</span> Observing System (TALOS) is a research program funded by the Greek Ministry of Education with the aim to promote excellence in the field of <span class="hlt">lightning</span> meteorology. The study focuses on exploring the real-time observations provided by the ZEUS <span class="hlt">lightning</span> detection system, operated by the National Observatory of Athens since 2005, as well as the 10-year long database of the same system. More precisely the main research issues explored are: - <span class="hlt">lightning</span> climatology over the Mediterranean focusing on <span class="hlt">lightning</span> spatial and temporal distribution, on the relation of <span class="hlt">lightning</span> with topographical features and instability and on the importance of aerosols in <span class="hlt">lightning</span> initiation and enhancement. - nowcasting of <span class="hlt">lightning</span> activity over Greece, with emphasis on the operational aspects of this endeavour. The nowcasting tool is based on the use of <span class="hlt">lightning</span> data complemented by high-time resolution METEOSAT imagery. - forecasting of <span class="hlt">lightning</span> activity over Greece based on the use of WRF numerical weather prediction model. - assimilation of <span class="hlt">lightning</span> with the aim to improve the model precipitation forecast skill. In the frame of this presentation the main findings of each of the aforementioned issues are highlighted.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.epa.gov/cmaq/users-guide-wrf-lightning-assimilation','PESTICIDES'); return false;" href="https://www.epa.gov/cmaq/users-guide-wrf-lightning-assimilation"><span>User's Guide - WRF <span class="hlt">Lightning</span> Assimilation</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>This document describes how to run WRF with the <span class="hlt">lightning</span> assimilation technique described in Heath et al. (2016). The assimilation method uses gridded <span class="hlt">lightning</span> data to trigger and suppress sub-grid deep convection in Kain-Fritsch.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NatCC...8..191M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NatCC...8..191M"><span>An uncertain future for <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Murray, Lee T.</p> <p>2018-03-01</p> <p>The most commonly used method for representing <span class="hlt">lightning</span> in global atmospheric models generally predicts <span class="hlt">lightning</span> increases in a warmer world. A new scheme finds the opposite result, directly challenging the predictive skill of an old stalwart.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title14-vol1/pdf/CFR-2010-title14-vol1-sec25-1316.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title14-vol1/pdf/CFR-2010-title14-vol1-sec25-1316.pdf"><span>14 CFR 25.1316 - System <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-01-01</p> <p>... airplane; (5) Establishing the susceptibility of the systems to the internal and external <span class="hlt">lightning</span>...) Determining the <span class="hlt">lightning</span> strike zones for the airplane; (2) Establishing the external <span class="hlt">lightning</span> environment for the zones; (3) Establishing the internal environment; (4) Identifying all the electrical and...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023316','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023316"><span><span class="hlt">Lightning</span> protection for shuttle propulsion elements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodloe, Carolyn C.; Giudici, Robert J.</p> <p>1991-01-01</p> <p>The results of <span class="hlt">lightning</span> protection analyses and tests are weighed against the present set of waivers to the NASA <span class="hlt">lightning</span> protection specification. The significant analyses and tests are contrasted with the release of a new and more realistic <span class="hlt">lightning</span> protection specification, in September 1990, that resulted in an inordinate number of waivers. A variety of <span class="hlt">lightning</span> protection analyses and tests of the Shuttle propulsion elements, the Solid Rocket Booster, the External Tank, and the Space Shuttle Main Engine, were conducted. These tests range from the sensitivity of solid propellant during shipping to penetration of cryogenic tanks during flight. The Shuttle propulsion elements have the capability to survive certain levels of <span class="hlt">lightning</span> strikes at certain times during transportation, launch site operations, and flight. Changes are being evaluated that may improve the odds of withstanding a major <span class="hlt">lightning</span> strike. The Solid Rocket Booster is the most likely propulsion element to survive if systems tunnel bond straps are improved. Wiring improvements were already incorporated and major protection tests were conducted. The External Tank remains vulnerable to burn-through penetration of its skin. Proposed design improvements include the use of a composite nose cone and conductive or laminated thermal protection system coatings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMGC33E1125K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMGC33E1125K"><span><span class="hlt">Lightning</span>-Related Indicators for National Climate Assessment (NCA) Studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Koshak, W. J.</p> <p>2017-12-01</p> <p>With the recent advent of space-based <span class="hlt">lightning</span> mappers [i.e., the Geostationary <span class="hlt">Lightning</span> Mapper (GLM) on GOES-16, and the <span class="hlt">Lightning</span> Imaging Sensor (LIS) on the International Space Station], improved investigations on the inter-relationships between <span class="hlt">lightning</span> and climate are now possible and can directly support the goals of the National Climate Assessment (NCA) program. <span class="hlt">Lightning</span> nitrogen oxides (LNOx) affect greenhouse gas concentrations such as ozone that influences changes in climate. Conversely, changes in climate (from any causes) can affect the characteristics of <span class="hlt">lightning</span> (e.g., frequency, current amplitudes, multiplicity, polarity) that in turn leads to changes in <span class="hlt">lightning</span>-caused impacts to humans (e.g., fatalities, injuries, crop/property damage, wildfires, airport delays, changes in air quality). This study discusses improvements to, and recent results from, the NASA/MSFC NCA <span class="hlt">Lightning</span> Analysis Tool (LAT). It includes key findings on the development of different types of <span class="hlt">lightning</span> flash energy indicators derived from space-based <span class="hlt">lightning</span> observations, and demonstrates how these indicators can be used to estimate trends in LNOx across the continental US.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMAE22A..02T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE22A..02T"><span><span class="hlt">Lightning</span> Enhancement Over Major Shipping Lanes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thornton, J. A.; Holzworth, R. H., II; Virts, K.; Mitchell, T. P.</p> <p>2017-12-01</p> <p>Using twelve years of high resolution global <span class="hlt">lightning</span> stroke data from the World Wide <span class="hlt">Lightning</span> Location Network (WWLLN), we show that <span class="hlt">lightning</span> density is enhanced by up to a factor of two directly over shipping lanes in the northeastern Indian Ocean and the South China Sea as compared to adjacent areas with similar climatological characteristics. The <span class="hlt">lightning</span> enhancement is most prominent during the convectively active season, November-April for the Indian Ocean and April - December in the South China Sea, and has been detectable from at least 2005 to the present. We hypothesize that emissions of aerosol particles and precursors by maritime vessel traffic leads to a microphysical enhancement of convection and storm electrification in the region of the shipping lanes. These persistent localized anthropogenic perturbations to otherwise clean regions are a unique opportunity to more thoroughly understand the sensitivity of maritime deep convection and <span class="hlt">lightning</span> to aerosol particles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730018655','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730018655"><span>A three-station <span class="hlt">lightning</span> detection system</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ruhnke, L. H.</p> <p>1972-01-01</p> <p>A three-station network is described which senses magnetic and electric fields of <span class="hlt">lightning</span>. Directional and distance information derived from the data are used to redundantly determine <span class="hlt">lightning</span> position. This redundancy is used to correct consistent propagation errors. A comparison is made of the relative accuracy of VLF direction finders with a newer method to determine distance to and location of <span class="hlt">lightning</span> by the ratio of magnetic-to-electric field as observed at 400 Hz. It was found that VLF direction finders can determine <span class="hlt">lightning</span> positions with only one-half the accuracy of the method that uses the ratio of magnetic-to-electric field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000004589','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000004589"><span><span class="hlt">Lightning</span> Protection Guidelines for Aerospace Vehicles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodloe, C. C.</p> <p>1999-01-01</p> <p>This technical memorandum provides <span class="hlt">lightning</span> protection engineering guidelines and technical procedures used by the George C. Marshall Space Flight Center (MSFC) Electromagnetics and Aerospace Environments Branch for aerospace vehicles. The overviews illustrate the technical support available to project managers, chief engineers, and design engineers to ensure that aerospace vehicles managed by MSFC are adequately protected from direct and indirect effects of <span class="hlt">lightning</span>. Generic descriptions of the <span class="hlt">lightning</span> environment and vehicle protection technical processes are presented. More specific aerospace vehicle requirements for <span class="hlt">lightning</span> protection design, performance, and interface characteristics are available upon request to the MSFC Electromagnetics and Aerospace Environments Branch, mail code EL23.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://rosap.ntl.bts.gov/view/dot/5236','DOTNTL'); return false;" href="https://rosap.ntl.bts.gov/view/dot/5236"><span>Electromagnetic Effects Harmonization Working Group (EEHWG) - <span class="hlt">Lightning</span> Task Group : report on aircraft <span class="hlt">lightning</span> strike data</span></a></p> <p><a target="_blank" href="http://ntlsearch.bts.gov/tris/index.do">DOT National Transportation Integrated Search</a></p> <p></p> <p>2002-07-01</p> <p>In 1995, in response to the <span class="hlt">lightning</span> community's desire to revise the zoning criteria on aircraft, the Electromagnetic Effects Harmonization Working Group (EEHWG) decided that <span class="hlt">lightning</span> attachments to aircraft causing damage should be studied and co...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820050176&hterms=thunderstorm+protection&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dthunderstorm%2Bprotection','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820050176&hterms=thunderstorm+protection&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dthunderstorm%2Bprotection"><span><span class="hlt">Lightning</span> protection of wind turbines</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dodd, C. W.</p> <p>1982-01-01</p> <p>Possible damages to wind turbine components due to <span class="hlt">lightning</span> strikes are discussed and means to prevent the damage are presented. A low resistance path to the ground is noted to be essential for any turbine system, including metal paths on nonmetal blades to conduct the strike. Surge arrestors are necessary to protect against overvoltages both from utility lines in normal operation and against <span class="hlt">lightning</span> damage to control equipment and contactors in the generator. MOS structures are susceptible to static discharge injury, as are other semiconductor devices, and must be protected by the presence of static protection circuitry. It is recommended that the electronics be analyzed for the circuit transient response to a <span class="hlt">lightning</span> waveform, to induced and dc current injection, that input/output leads be shielded, everything be grounded, and <span class="hlt">lightning</span>-resistant components be chosen early in the design phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1982ATJSE.104..121D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1982ATJSE.104..121D"><span><span class="hlt">Lightning</span> protection of wind turbines</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dodd, C. W.</p> <p>1982-05-01</p> <p>Possible damages to wind turbine components due to <span class="hlt">lightning</span> strikes are discussed and means to prevent the damage are presented. A low resistance path to the ground is noted to be essential for any turbine system, including metal paths on nonmetal blades to conduct the strike. Surge arrestors are necessary to protect against overvoltages both from utility lines in normal operation and against <span class="hlt">lightning</span> damage to control equipment and contactors in the generator. MOS structures are susceptible to static discharge injury, as are other semiconductor devices, and must be protected by the presence of static protection circuitry. It is recommended that the electronics be analyzed for the circuit transient response to a <span class="hlt">lightning</span> waveform, to induced and dc current injection, that input/output leads be shielded, everything be grounded, and <span class="hlt">lightning</span>-resistant components be chosen early in the design phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1022790','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1022790"><span>Neurologic complications of <span class="hlt">lightning</span> injuries.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cherington, M; Yarnell, P R; London, S F</p> <p>1995-01-01</p> <p>Over the past ten years, we have cared for 13 patients who suffered serious neurologic complications after being struck by <span class="hlt">lightning</span>. The spectrum of neurologic lesions includes the entire neuraxis from the cerebral hemispheres to the peripheral nerves. We describe these various neurologic disorders with regard to the site of the lesion, severity of the deficit, and the outcome. Damage to the nervous system can be a serious problem for patients struck by <span class="hlt">lightning</span>. Fatalities are associated with hypoxic encephalopathy in patients who suffered cardiac arrests. Patients with spinal cord lesions are likely to have permanent sequelae and paralysis. New technology for detecting <span class="hlt">lightning</span> with wideband magnetic direction finders is useful in establishing <span class="hlt">lightning</span>-flash densities in each state. Florida and the Gulf Coast states have the highest densities. Colorado and the Rocky Mountain states have the next highest. Images PMID:7785254</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920045362&hterms=Global+warming&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DGlobal%2Bwarming','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920045362&hterms=Global+warming&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DGlobal%2Bwarming"><span>The effect of global warming on <span class="hlt">lightning</span> frequencies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Price, Colin; Rind, David</p> <p>1990-01-01</p> <p>The first attempt to model global <span class="hlt">lightning</span> distributions by using the Goddard Institute for Space Studies (GISS) GCM is reported. Three sets of observations showing the relationship between <span class="hlt">lightning</span> frequency and cloud top height are shown. Zonally averaged <span class="hlt">lightning</span> frequency observed by satellite are compared with those calculated using the GISS GCM, and fair agreement is found. The change in <span class="hlt">lightning</span> frequency for a double CO2 climate is calculated and found to be nearly 2.23 x 10 exp 6 extra <span class="hlt">lightning</span> flashes per day.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1320247','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1320247"><span>A Model <span class="hlt">Lightning</span> Safety Policy for Athletics</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bennett, Brian L.</p> <p>1997-01-01</p> <p>Objective: The purpose of this paper is to present a model policy on <span class="hlt">lightning</span> safety for athletic trainers. Background: Among college athletic programs in the United States there is a serious lack of written policy on <span class="hlt">lightning</span> safety. Available evidence shows that most National Collegiate Athletic Association (NCAA) Division I institutions, even though they are located in high <span class="hlt">lightning</span> activity areas of the country, do not have formal, written <span class="hlt">lightning</span> safety policies. Clinical Advantages/ Recommendations: The policy presented herein, which is at the forefront of such policies, is the <span class="hlt">lightning</span> safety policy written as part of a policies and procedures manual for the division of sports medicine at a public NCAA Division I university. This is a policy based on practicality that utilizes the “flash-to- bang” method for determining the distance of <span class="hlt">lightning</span> activity from the observer. The policy begins with the importance of prevention, including the daily monitoring of weather reports. The policy defines a “safe shelter” and specifies the chain of command for determining who removes a team or individuals from an athletic site in the event of dangerous <span class="hlt">lightning</span> activity. PMID:16558459</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/587206-sub-from-lightning-global-distribution-based-lightning-physics','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/587206-sub-from-lightning-global-distribution-based-lightning-physics"><span>NO{sub x} from <span class="hlt">lightning</span> 1. Global distribution based on <span class="hlt">lightning</span> physics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Price, C.; Penner, J.; Prather, M.</p> <p>1997-03-01</p> <p>This paper begins a study on the role of <span class="hlt">lightning</span> in maintaining the global distribution of nitrogen oxides (NO{sub x}) in the troposphere. It presents the first global and seasonal distributions of <span class="hlt">lightning</span>-produced NO{sub x} (LNO{sub x}) based on the observed distribution of electrical storms and the physical properties of <span class="hlt">lightning</span> strokes. We derive a global rate for cloud-to-ground (CG) flashes of 20{endash}30 flashes/s with a mean energy per flash of 6.7{times}10{sup 9}J. Intracloud (IC) flashes are more frequent, 50{endash}70 flashes/s but have 10{percent} of the energy of CG strokes and, consequently, produce significantly less NO{sub x}. It appears tomore » us that the majority of previous studies have mistakenly assumed that all <span class="hlt">lightning</span> flashes produce the same amount of NO{sub x}, thus overestimating the NO{sub x} production by a factor of 3. On the other hand, we feel these same studies have underestimated the energy released in CG flashes, resulting in two negating assumptions. For CG energies we adopt a production rate of 10{times}10{sup 16} molecules NO/J based on the current literature. Using a method to simulate global <span class="hlt">lightning</span> frequencies from satellite-observed cloud data, we have calculated the LNO{sub x} on various spatial (regional, zonal, meridional, and global) and temporal scales (daily, monthly, seasonal, and interannual). Regionally, the production of LNO{sub x} is concentrated over tropical continental regions, predominantly in the summer hemisphere. The annual mean production rate is calculated to be 12.2 Tg N/yr, and we believe it extremely unlikely that this number is less than 5 or more than 20 Tg N/yr. Although most of LNO{sub x} is produced in the lowest 5 km by CG <span class="hlt">lightning</span>, convective mixing in the thunderstorms is likely to deposit large amounts of NO{sub x} in the upper troposphere where it is important in ozone production. (Abstract Truncated)« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150001382','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150001382"><span>Exploring <span class="hlt">Lightning</span> Jump Characteristics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chronis, Themis; Carey, Larry D.; Schultz, Christopher J.; Schultz, Elise; Calhoun, Kristin; Goodman, Steven J.</p> <p>2014-01-01</p> <p>This study is concerned with the characteristics of storms exhibiting an abrupt temporal increase in the total <span class="hlt">lightning</span> flash rate (i.e., <span class="hlt">lightning</span> jump, LJ). An automated storm tracking method is used to identify storm "clusters" and total <span class="hlt">lightning</span> activity from three different <span class="hlt">lightning</span> detection systems over Oklahoma, northern Alabama and Washington, D.C. On average and for different employed thresholds, the clusters that encompass at least one LJ (LJ1) last longer, relate to higher Maximum Expected Size of Hail, Vertical Integrated Liquid and <span class="hlt">lightning</span> flash rates (area-normalized) than the clusters that did not exhibit any LJ (LJ0). The respective mean values for LJ1 (LJ0) clusters are 80 min (35 min), 14 mm (8 mm), 25 kg per square meter (18 kg per square meter) and 0.05 flash per min per square kilometer (0.01 flash per min per square kilometer). Furthermore, the LJ1 clusters are also characterized by slower decaying autocorrelation functions, a result that implies a less "random" behavior in the temporal flash rate evolution. In addition, the temporal occurrence of the last LJ provides an estimate of the time remaining to the storm's dissipation. Depending of the LJ strength (i.e., varying thresholds), these values typically range between 20-60 min, with stronger jumps indicating more time until storm decay. This study's results support the hypothesis that the LJ is a proxy for the storm's kinematic and microphysical state rather than a coincidental value.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120004306','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120004306"><span>Stemless <span class="hlt">ball</span> valve</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burgess, Kevin (Inventor); Yakos, David (Inventor); Walthall, Bryan (Inventor)</p> <p>2012-01-01</p> <p>A stemless <span class="hlt">ball</span> valve comprising: a right flange; left flange; <span class="hlt">ball</span> with an axis pin and two travel pins; <span class="hlt">ball</span> seal on either side of the <span class="hlt">ball</span>; guide sleeve with inner walls comprising two channels; cartridge guide holder; inner magnetic cartridge; and outer magnetic cartridge. The <span class="hlt">ball</span> is situated inside of the guide sleeve, and a travel pin is located in each of the two channels. The guide sleeve is situated inside of the cartridge guide holder, which is located adjacent to and outside of the inner magnetic cartridge and secured to the inner magnetic cartridge such that when the inner magnetic cartridge rotates, the cartridge guide holder also rotates. The cartridge guide holder is secured to the guide sleeve such that when the cartridge guide holder rotates, the travel pins move within the channels in the inner walls of the guide sleeve, thereby causing the <span class="hlt">ball</span> to rotate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990008509','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990008509"><span>Optical Detection of <span class="hlt">Lightning</span> from Space</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Boccippio, Dennis J.; Christian, Hugh J.</p> <p>1998-01-01</p> <p>Optical sensors have been developed to detect <span class="hlt">lightning</span> from space during both day and night. These sensors have been fielded in two existing satellite missions and may be included on a third mission in 2002. Satellite-hosted, optically-based <span class="hlt">lightning</span> detection offers three unique capabilities: (1) the ability to reliably detect <span class="hlt">lightning</span> over large, often remote, spatial regions, (2) the ability to sample all (IC and CG) <span class="hlt">lightning</span>, and (3) the ability to detect <span class="hlt">lightning</span> with uniform (i.e., not range-dependent) sensitivity or detection efficiency. These represent significant departures from conventional RF-based detection techniques, which typically have strong range dependencies (biases) or range limitations in their detection capabilities. The atmospheric electricity team of the NASA Marshall Space Flight Center's Global Hydrology and Climate Center has implemented a three-step satellite <span class="hlt">lightning</span> research program which includes three phases: proof-of-concept/climatology, science algorithm development, and operational application. The first instrument in the program, the Optical Transient Detector (OTD), is deployed on a low-earth orbit (LEO) satellite with near-polar inclination, yielding global coverage. The sensor has a 1300 x 1300 sq km field of view (FOV), moderate detection efficiency, moderate localization accuracy, and little data bias. The OTD is a proof-of-concept instrument and its mission is primarily a global <span class="hlt">lightning</span> climatology. The limited spatial accuracy of this instrument makes it suboptimal for use in case studies, although significant science knowledge has been gained from the instrument as deployed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150022939','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150022939"><span>The Intra-Cloud <span class="hlt">Lightning</span> Fraction in the Contiguous United States</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Medici, Gina; Cummins, Kenneth L.; Koshak, William J.; Rudlosky, Scott D.; Blakeslee, Richard J.; Goodman, Steven J.; Cecil, Daniel J.; Bright, David R.</p> <p>2015-01-01</p> <p><span class="hlt">Lightning</span> is dangerous and destructive; cloud-to-ground (CG) <span class="hlt">lightning</span> flashes can start fires, interrupt power delivery, destroy property and cause fatalities. Its rate-of-occurrence reflects storm kinematics and microphysics. For decades <span class="hlt">lightning</span> research has been an important focus, and advances in <span class="hlt">lightning</span> detection technology have been essential contributors to our increasing knowledge of <span class="hlt">lightning</span>. A significant step in detection technology is the Geostationary <span class="hlt">Lightning</span> Mapper (GLM) to be onboard the Geostationary Operational Environment Satellite R-Series (GOES-R) to be launched in early 2016. GLM will provide continuous "Total <span class="hlt">Lightning</span>" observations [CG and intra-cloud <span class="hlt">lightning</span> (IC)] with near-uniform spatial resolution over the Americas by measuring radiance at the cloud tops from the different types of <span class="hlt">lightning</span>. These Total <span class="hlt">Lightning</span> observations are expected to significantly improve our ability to nowcast severe weather. It may be important to understand the long-term regional differences in the relative occurrence of IC and CG <span class="hlt">lightning</span> in order to understand and properly use the short-term changes in Total <span class="hlt">Lightning</span> flash rate for evaluating individual storms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160014743','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160014743"><span>Preparations for Integrating Space-Based Total <span class="hlt">Lightning</span> Observations into Forecast Operations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stano, Geoffrey T.; Fuell, Kevin K.; Molthan, Andrew L.</p> <p>2016-01-01</p> <p>NASA's Short-term Prediction Research and Transition (SPoRT) Center has been a leader in collaborating with the United States National Weather Service (NWS) offices to integrate ground-based total <span class="hlt">lightning</span> (intra-cloud and cloud-to-ground) observations into the real-time operational environment. For much of these collaborations, the emphasis has been on training, dissemination of data to the NWS AWIPS system, and focusing on the utility of these data in the warning decision support process. A shift away from this paradigm has occurred more recently for several reasons. For one, SPoRT's collaborations have expanded to new partners, including emergency managers and the aviation community. Additionally, and most importantly, is the impending launch of the GOES-R Geostationary <span class="hlt">Lightning</span> Mapper (GLM). This has led to collaborative efforts to focus on additional forecast needs, new data displays, develop training for GLM uses based on the lessons learned from ground-based <span class="hlt">lightning</span> mapping arrays, and ways to better relate total <span class="hlt">lightning</span> data to other meteorological parameters. This presentation will focus on these efforts to prepare the operational end user community for GLM with an eye towards sharing lessons learned as EUMETSAT prepares for the Meteosat Third Generation <span class="hlt">Lightning</span> Imager. This will focus on both software and training needs. In particular, SPoRT has worked closely with the Meteorological Development <span class="hlt">Laboratory</span> to create the total <span class="hlt">lightning</span> tracking tool. This software allows for NWS forecasters to manually track storms of interest and display a time series trend of observations. This tool also has been expanded to work on any gridded data set allowing for easy visual comparisons of multiple parameters in addition to total <span class="hlt">lightning</span>. A new web display has been developed for the ground-based observations that can be easily extended to satellite observations. This paves the way for new collaborations outside of the NWS, both domestically and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=335488&Lab=NERL&keyword=forensics&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=335488&Lab=NERL&keyword=forensics&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span><span class="hlt">Lightning</span> NOx Production in CMAQ Part I – Using Hourly NLDN <span class="hlt">Lightning</span> Strike Data</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p><span class="hlt">Lightning</span>-produced nitrogen oxides (NOX=NO+NO2) in the middle and upper troposphere play an essential role in the production of ozone (O3) and influence the oxidizing capacity of the troposphere. Despite much effort in both observing and modeling <span class="hlt">lightning</span> NOX during the past dec...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120014476','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120014476"><span>Using the VAHIRR Radar Algorithm to Investigate <span class="hlt">Lightning</span> Cessation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stano, Geoffrey T.; Schultz, Elise V.; Petersen, Walter A.</p> <p>2012-01-01</p> <p>Accurately determining the threat posed by <span class="hlt">lightning</span> is a major area for improved operational forecasts. Most efforts have focused on the initiation of <span class="hlt">lightning</span> within a storm, with far less effort spent investigating <span class="hlt">lightning</span> cessation. Understanding both components, initiation and cessation, are vital to improving <span class="hlt">lightning</span> safety. Few organizations actively forecast <span class="hlt">lightning</span> onset or cessation. One such organization is the 45th Weather Squadron (45WS) for the Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS). The 45WS has identified that charged anvil clouds remain a major threat of continued <span class="hlt">lightning</span> and can greatly extend the window of a potential <span class="hlt">lightning</span> strike. Furthermore, no discernable trend of total <span class="hlt">lightning</span> activity has been observed consistently for all storms. This highlights the need for more research to find a robust method of knowing when a storm will cease producing <span class="hlt">lightning</span>. Previous <span class="hlt">lightning</span> cessation work has primarily focused on forecasting the cessation of cloud-to -ground <span class="hlt">lightning</span> only. A more recent, statistical study involved total <span class="hlt">lightning</span> (both cloud-to-ground and intracloud). Each of these previous works has helped the 45WS take steps forward in creating improved and ultimately safer <span class="hlt">lightning</span> cessation forecasts. Each study has either relied on radar data or recommended increased use of radar data to improve cessation forecasts. The reasoning is that radar data is able to either directly or by proxy infer more about dynamical environment leading to cloud electrification and eventually <span class="hlt">lightning</span> cessation. The authors of this project are focusing on a two ]step approach to better incorporate radar data and total <span class="hlt">lightning</span> to improve cessation forecasts. This project will utilize the Volume Averaged Height Integrated Radar Reflectivity (VAHIRR) algorithm originally developed during the Airborne Field Mill II (ABFM II) research project. During the project, the VAHIRR product showed a trend of increasing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900005749&hterms=thunderstorm+protection&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dthunderstorm%2Bprotection','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900005749&hterms=thunderstorm+protection&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dthunderstorm%2Bprotection"><span>Effects of <span class="hlt">lightning</span> on operations of aerospace vehicles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fisher, Bruce D.</p> <p>1989-01-01</p> <p>Traditionally, aircraft <span class="hlt">lightning</span> strikes were a major aviation safety issue. However, the increasing use of composite materials and the use of digital avionics for flight critical systems will require that more specific <span class="hlt">lightning</span> protection measures be incorporated in the design of such aircraft in order to maintain the excellent <span class="hlt">lightning</span> safety record presently enjoyed by transport aircraft. In addition, several recent <span class="hlt">lightning</span> mishaps, most notably the loss of the Atlas/Centaur-67 vehicle at Cape Canaveral Air Force Station, Florida in March 1987, have shown the susceptibility of aircraft and launch vehicles to the phenomenon of vehicle-triggered <span class="hlt">lightning</span>. The recent findings of the NASA Storm Hazards Program were reviewed as they pertain to the atmospheric conditions conducive to aircraft <span class="hlt">lightning</span> strikes. These data are then compared to recent summaries of <span class="hlt">lightning</span> strikes to operational aircraft fleets. Finally, the new launch commit criteria for triggered <span class="hlt">lightning</span> being used by NASA and the U.S. Defense Department are summarized. The NASA Research data show that the greatest probability of a direct strike in a thunderstorm occurs at ambient temperatures of about -40 C. Relative precipitation and turbulence levels were characterized as negligible to light for these conditions. However, operational fleet data have shown that most aircraft <span class="hlt">lightning</span> strikes in routine operations occur at temperatures near the freezing level in non-cumulonimbus clouds. The non-thunderstorm environment was not the subject of dedicated airborne <span class="hlt">lightning</span> research.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27336208','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27336208"><span>Novel device for male infertility screening with single-<span class="hlt">ball</span> lens microscope and smartphone.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kobori, Yoshitomo; Pfanner, Peter; Prins, Gail S; Niederberger, Craig</p> <p>2016-09-01</p> <p>To investigate the usefulness of a novel semen analysis device consisting of a single-<span class="hlt">ball</span> lens microscope paired with a state-of-the-art smartphone equipped with a camera. <span class="hlt">Laboratory</span> investigation. University research <span class="hlt">laboratory</span>. A total of 50 semen samples obtained from volunteers were analyzed for count, concentration, and motility with an 0.8-mm <span class="hlt">ball</span> lens and three types of smartphone. Comparisons were made with results obtained with a <span class="hlt">laboratory</span>-based computer-assisted sperm analysis (CASA) system. None. Sperm concentration; sperm motility. Sperm concentration counted with a <span class="hlt">ball</span> lens and each smartphone showed a very strong correlation with the CASA results. Likewise, sperm motility calculated with our device showed significant correlations to CASA. If eight spermatozoa or fewer were found on the field of view of an iPhone 6s, the semen specimens were considered to be below the lower reference limit for sperm concentration of World Health Organization 2010 guidelines (15 × 10(6) spermatozoa/mL). The sensitivity was 87.5%, and specificity was 90.9%. Smartphones have great potential to analyze semen because they are portable, contain excellent digital cameras, and can be easily attached to a microscope. A single-<span class="hlt">ball</span> lens microscope is inexpensive and easy to use for acquiring digital microscopic movies. Given its small size and weight, the device can support testing for male fertility at home or in the field, making it much more convenient and economical than current practice. This single-<span class="hlt">ball</span> lens microscope provides an easy solution for global users to rapidly screen for male infertility. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730002931','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730002931"><span><span class="hlt">Lightning</span> criteria relative to space shuttles: Currents and electric field intensity in Florida <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Uman, M. A.; Mclain, D. K.</p> <p>1972-01-01</p> <p>The measured electric field intensities of 161 <span class="hlt">lightning</span> strokes in 39 flashes which occurred between 1 and 35 km from an observation point at Kennedy Space Center, Florida during June and July of 1971 have been analyzed to determine the <span class="hlt">lightning</span> channel currents which produced the fields. In addition, typical channel currents are derived and from these typical electric fields at distances between 0.5 and 100 km are computed and presented. On the basis of the results recommendations are made for changes in the specification of <span class="hlt">lightning</span> properties relative to space vehicle design as given in NASA TMX-64589 (Daniels, 1971). The small sample of <span class="hlt">lightning</span> analyzed yielded several peak currents in the 100 kA range. Several current rise-times from zero to peak of 0.5 microsec or faster were found; and the fastest observed current rate-of-rise was near 200 kA/microsec. The various sources of error are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19960020732','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19960020732"><span><span class="hlt">Lightning</span> electromagnetics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wahid, Parveen</p> <p>1995-01-01</p> <p>This project involved the determination of the effective radiated power of <span class="hlt">lightning</span> sources and the polarization of the radiating source. This requires the computation of the antenna patterns at all the LDAR site receiving antennas. The known radiation patterns and RF signal levels measured at the antennas will be used to determine the effective radiated power of the <span class="hlt">lightning</span> source. The azimuth and elevation patterns of the antennas in the LDAR system were computed using flight test data that was gathered specifically for this purpose. The results presented in this report deal with the azimuth patterns for all the antennas and the elevation patterns for three of the seven sites.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28465545','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28465545"><span>On the initiation of <span class="hlt">lightning</span> in thunderclouds.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chilingarian, Ashot; Chilingaryan, Suren; Karapetyan, Tigran; Kozliner, Lev; Khanikyants, Yeghia; Hovsepyan, Gagik; Pokhsraryan, David; Soghomonyan, Suren</p> <p>2017-05-02</p> <p>The relationship of <span class="hlt">lightning</span> and elementary particle fluxes in the thunderclouds is not fully understood to date. Using the particle beams (the so-called Thunderstorm Ground Enhancements - TGEs) as a probe we investigate the characteristics of the interrelated atmospheric processes. The well-known effect of the TGE dynamics is the abrupt termination of the particle flux by the <span class="hlt">lightning</span> flash. With new precise electronics, we can see that particle flux decline occurred simultaneously with the rearranging of the charge centers in the cloud. The analysis of the TGE energy spectra before and after the <span class="hlt">lightning</span> demonstrates that the high-energy part of the TGE energy spectra disappeared just after <span class="hlt">lightning</span>. The decline of particle flux coincides on millisecond time scale with first atmospheric discharges and we can conclude that Relativistic Runaway Electron Avalanches (RREA) in the thundercloud assist initiation of the negative cloud to ground <span class="hlt">lightning</span>. Thus, RREA can provide enough ionization to play a significant role in the unleashing of the <span class="hlt">lightning</span> flash.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMAE31B0430S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMAE31B0430S"><span>Scientific <span class="hlt">Lightning</span> Detection Network for Kazakhstan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Streltsov, A. V.; Lozbin, A.; Inchin, A.; Shpadi, Y.; Inchin, P.; Shpadi, M.; Ayazbayev, G.; Bykayev, R.; Mailibayeva, L.</p> <p>2015-12-01</p> <p>In the frame of grant financing of the scientific research in 2015-2017 the project "To Develop Electromagnetic System for <span class="hlt">lightning</span> location and atmosphere-lithosphere coupling research" was found. The project was start in January, 2015 and should be done during 3 years. The purpose is to create a system of electromagnetic measurements for <span class="hlt">lightning</span> location and atmosphere-lithosphere coupling research consisting of a network of electric and magnetic sensors and the dedicated complex for data processing and transfer to the end user. The main tasks are to set several points for electromagnetic measurements with 100-200 km distance between them, to develop equipment for these points, to develop the techniques and software for <span class="hlt">lightning</span> location (Time-of-arrival and Direction Finding (TOA+DF)) and provide a <span class="hlt">lightning</span> activity research in North Tien-Shan region with respect to seismicity and other natural and manmade activities. Also, it is planned to use <span class="hlt">lightning</span> data for Global Electric Circuit (GEC) investigation. Currently, there are <span class="hlt">lightning</span> detection networks in many countries. In Kazakhstan we have only separate units in airports. So, we don't have full <span class="hlt">lightning</span> information for our region. It is planned, to setup 8-10 measurement points with magnetic and electric filed antennas for VLF range. The final data set should be including each stroke location, time, type (CG+, CG-, CC+ or CC-) and waveform from each station. As the magnetic field <span class="hlt">lightning</span> antenna the ferrite rod VLF antenna will be used. As the electric field antenna the wide range antenna with specific frequencies filters will be used. For true event detection TOA and DF methods needs detected stroke from minimum 4 stations. In this case we can get location accuracy about 2-3 km and better.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/36768','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/36768"><span>Relating <span class="hlt">lightning</span> data to fire occurrence data</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Frank H. Koch</p> <p>2009-01-01</p> <p><span class="hlt">Lightning</span> disturbance can affect forest health at various scales. <span class="hlt">Lightning</span> strikes may kill or weaken individual trees. <span class="hlt">Lightning</span>-damaged trees may in turn function as epicenters of pest outbreaks in forest stands, as is the case with the southern pine beetle and other bark beetles (Rykiel and others 1988).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title14-vol1/pdf/CFR-2011-title14-vol1-sec25-1316.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title14-vol1/pdf/CFR-2011-title14-vol1-sec25-1316.pdf"><span>14 CFR 25.1316 - System <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-01-01</p> <p>... systems to perform these functions are not adversely affected when the airplane is exposed to <span class="hlt">lightning</span>... these functions can be recovered in a timely manner after the airplane is exposed to <span class="hlt">lightning</span>. (c) Compliance with the <span class="hlt">lightning</span> protection criteria prescribed in paragraphs (a) and (b) of this section must...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990036563','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990036563"><span>Electro-optic <span class="hlt">Lightning</span> Detector</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William J.; Solakiewicz, Richard J.</p> <p>1996-01-01</p> <p>The design, alignment, calibration, and field deployment of a solid-state <span class="hlt">lightning</span> detector is described. The primary sensing component of the detector is a potassium dihydrogen phosphate (KDP) electro-optic crystal that is attached in series to a flat plate aluminum antenna; the antenna is exposed to the ambient thundercloud electric field. A semiconductor laser diode (lambda = 685 nm), polarizing optics, and the crystal are arranged in a Pockels cell configuration. <span class="hlt">Lightning</span>-caused electric field changes are related to small changes in the transmission of laser light through the optical cell. Several hundred <span class="hlt">lightning</span> electric field change excursions were recorded during five thunderstorms that occurred in the summer of 1998 at the NASA Marshall Space Flight Center (MSFC) in northern Alabama.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFMSA21B0084H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFMSA21B0084H"><span>Ionospheric signatures of <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hsu, M.; Liu, J.</p> <p>2003-12-01</p> <p>The geostationary metrology satellite (GMS) monitors motions of thunderstorm cloud, while the <span class="hlt">lightning</span> detection network (LDN) in Taiwan and the very high Frequency (VHF) radar in Chung-Li (25.0›XN, 121.2›XE) observed occurrences of <span class="hlt">lightning</span> during May and July, 1997. Measurements from the digisonde portable sounder (DPS) at National Central University shows that <span class="hlt">lightning</span> results in occurrence of the sporadic E-layer (Es), as well as increase and decrease of plasma density at the F2-peak and E-peak in the ionosphere, respectively. A network of ground-based GPS receivers is further used to monitor the spatial distribution of the ionospheric TEC. To explain the plasma density variations, a model is proposed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990106243&hterms=applied+optics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dapplied%2Boptics','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990106243&hterms=applied+optics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dapplied%2Boptics"><span>Electro-Optic <span class="hlt">Lightning</span> Detector</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, Willliam; Solakiewicz, Richard</p> <p>1998-01-01</p> <p>The design, alignment, calibration, and field deployment of a solid-state <span class="hlt">lightning</span> detector is described. The primary sensing component of the detector is a potassium dihydrogen phosphate (KDP) electro-optic crystal that is attached in series to a flat plate aluminum antenna; the antenna is exposed to the ambient thundercloud electric field. A semiconductor laser diode (lambda = 685 nm), polarizing optics, and the crystal are arranged in a Pockels cell configuration. <span class="hlt">Lightning</span>-caused electric field changes are then related to small changes in the transmission of laser light through the optical cell. Several hundred <span class="hlt">lightning</span> electric field change excursions were recorded during 4 thunderstorms that occurred in the summer of 1998 at the NASA Marshall Space Flight Center (MSFC) in Northern Alabama.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=thunder&pg=3&id=EJ027314','ERIC'); return false;" href="https://eric.ed.gov/?q=thunder&pg=3&id=EJ027314"><span><span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Pampe, William R.</p> <p>1970-01-01</p> <p>Presents basic physical theory for movement of electric charges in clouds, earth, and air during production of <span class="hlt">lightning</span> and thunder. Amount of electrical energy produced and heating effects during typical thunderstorms is described. Generalized safety practices are given. (JM)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19970012901&hterms=nasa+shuttle&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dnasa%2Bshuttle','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19970012901&hterms=nasa+shuttle&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dnasa%2Bshuttle"><span>NASA Shuttle <span class="hlt">Lightning</span> Research: Observations of Nocturnal Thunderstorms and <span class="hlt">Lightning</span> Displays as Seen During Recent Space Shuttle Missions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Vaughan, Otha H., Jr.</p> <p>1994-01-01</p> <p>A number of interesting <span class="hlt">lightning</span> events have been observed using the low light level TV camera of the space shuttle during nighttime observations of thunderstorms near the limb of the Earth. Some of the vertical type <span class="hlt">lightning</span> events that have been observed will be presented. Using TV cameras for observing <span class="hlt">lightning</span> near the Earth's limb allows one to determine the location of the <span class="hlt">lightning</span> and other characteristics by using the star field data and the shuttle's orbital position to reconstruct the geometry of the scene being viewed by the shuttle's TV cameras which are located in the payload bay of the shuttle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023303','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023303"><span><span class="hlt">Lightning</span> location system supervising Swedish power transmission network</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Melin, Stefan A.</p> <p>1991-01-01</p> <p>For electric utilities, the ability to prevent or minimize <span class="hlt">lightning</span> damage on personnel and power systems is of great importance. Therefore, the Swedish State Power Board, has been using data since 1983 from a nationwide <span class="hlt">lightning</span> location system (LLS) for accurately locating <span class="hlt">lightning</span> ground strikes. <span class="hlt">Lightning</span> data is distributed and presented on color graphic displays at regional power network control centers as well as at the national power system control center for optimal data use. The main objectives for use of LLS data are: supervising the power system for optimal and safe use of the transmission and generating capacity during periods of thunderstorms; warning service to maintenance and service crews at power line and substations to end operations hazardous when <span class="hlt">lightning</span>; rapid positioning of emergency crews to locate network damage at areas of detected <span class="hlt">lightning</span>; and post analysis of power outages and transmission faults in relation to <span class="hlt">lightning</span>, using archived <span class="hlt">lightning</span> data for determination of appropriate design and insulation levels of equipment. Staff have found LLS data useful and economically justified since the availability of power system has increased as well as level of personnel safety.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMAE23A..03J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMAE23A..03J"><span>High-Speed Video Observations of a Natural <span class="hlt">Lightning</span> Stepped Leader</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jordan, D. M.; Hill, J. D.; Uman, M. A.; Yoshida, S.; Kawasaki, Z.</p> <p>2010-12-01</p> <p>High-speed video images of one branch of a natural negative <span class="hlt">lightning</span> stepped leader were obtained at a frame rate of 300 kfps (3.33 us exposure) on June 18th, 2010 at the International Center for <span class="hlt">Lightning</span> Research and Testing (ICLRT) located on the Camp Blanding Army National Guard Base in north-central Florida. The images were acquired using a 20 mm Nikon lens mounted on a Photron SA1.1 high-speed camera. A total of 225 frames (about 0.75 ms) of the downward stepped leader were captured, followed by 45 frames of the leader channel re-illumination by the return stroke and subsequent decay following the ground attachment of the primary leader channel. Luminous characteristics of dart-stepped leader propagation in triggered <span class="hlt">lightning</span> obtained by Biagi et al. [2009, 2010] and of long <span class="hlt">laboratory</span> spark formation [e.g., Bazelyan and Raizer, 1998; Gallimberti et al., 2002] are evident in the frames of the natural <span class="hlt">lightning</span> stepped leader. Space stems/leaders are imaged in twelve different frames at various distances in front of the descending leader tip, which branches into two distinct components 125 frames after the channel enters the field of view. In each case, the space stem/leader appears to connect to the leader tip above in the subsequent frame, forming a new step. Each connection is associated with significant isolated brightening of the channel at the connection point followed by typically three or four frames of upward propagating re-illumination of the existing leader channel. In total, at least 80 individual steps were imaged.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMAE33A0273A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMAE33A0273A"><span>Acoustic Network Localization and Interpretation of Infrasonic Pulses from <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arechiga, R. O.; Johnson, J. B.; Badillo, E.; Michnovicz, J. C.; Thomas, R. J.; Edens, H. E.; Rison, W.</p> <p>2011-12-01</p> <p>We improve on the localization accuracy of thunder sources and identify infrasonic pulses that are correlated across a network of acoustic arrays. We attribute these pulses to electrostatic charge relaxation (collapse of the electric field) and attempt to model their spatial extent and acoustic source strength. Toward this objective we have developed a single audio range (20-15,000 Hz) acoustic array and a 4-station network of broadband (0.01-500 Hz) microphone arrays with aperture of ~45 m. The network has an aperture of 1700 m and was installed during the summers of 2009-2011 in the Magdalena mountains of New Mexico, an area that is subject to frequent <span class="hlt">lightning</span> activity. We are exploring a new technique based on inverse theory that integrates information from the audio range and the network of broadband acoustic arrays to locate thunder sources more accurately than can be achieved with a single array. We evaluate the performance of the technique by comparing the location of thunder sources with RF sources located by the <span class="hlt">lightning</span> mapping array (LMA) of Langmuir <span class="hlt">Laboratory</span> at New Mexico Tech. We will show results of this technique for <span class="hlt">lightning</span> flashes that occurred in the vicinity of our network of acoustic arrays and over the LMA. We will use acoustic network detection of infrasonic pulses together with LMA data and electric field measurements to estimate the spatial distribution of the charge (within the cloud) that is used to produce a <span class="hlt">lightning</span> flash, and will try to quantify volumetric charges (charge magnitude) within clouds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-PIA22474.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-PIA22474.html"><span>Artist's Concept of Jupiter <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2018-06-06</p> <p>This artist's concept of <span class="hlt">lightning</span> distribution in Jupiter's northern hemisphere incorporates a JunoCam image with artistic embellishments. Data from NASA's Juno mission indicates that most of the <span class="hlt">lightning</span> activity on Jupiter is near its poles. https://photojournal.jpl.nasa.gov/catalog/PIA22474</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15...32P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15...32P"><span>Visual Analytics approach for <span class="hlt">Lightning</span> data analysis and cell nowcasting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Peters, Stefan; Meng, Liqiu; Betz, Hans-Dieter</p> <p>2013-04-01</p> <p>Thunderstorms and their ground effects, such as flash floods, hail, <span class="hlt">lightning</span>, strong wind and tornadoes, are responsible for most weather damages (Bonelli & Marcacci 2008). Thus to understand, identify, track and predict <span class="hlt">lightning</span> cells is essential. An important aspect for decision makers is an appropriate visualization of weather analysis results including the representation of dynamic <span class="hlt">lightning</span> cells. This work focuses on the visual analysis of <span class="hlt">lightning</span> data and <span class="hlt">lightning</span> cell nowcasting which aim to detect and understanding spatial-temporal patterns of moving thunderstorms. <span class="hlt">Lightnings</span> are described by 3D coordinates and the exact occurrence time of <span class="hlt">lightnings</span>. The three-dimensionally resolved total <span class="hlt">lightning</span> data used in our experiment are provided by the European <span class="hlt">lightning</span> detection network LINET (Betz et al. 2009). In all previous works, <span class="hlt">lightning</span> point data, detected <span class="hlt">lightning</span> cells and derived cell tracks are visualized in 2D. <span class="hlt">Lightning</span> cells are either displayed as 2D convex hulls with or without the underlying <span class="hlt">lightning</span> point data. Due to recent improvements of <span class="hlt">lightning</span> data detection and accuracy, there is a growing demand on multidimensional and interactive visualization in particular for decision makers. In a first step <span class="hlt">lightning</span> cells are identified and tracked. Then an interactive graphic user interface (GUI) is developed to investigate the dynamics of the <span class="hlt">lightning</span> cells: e.g. changes of cell density, location, extension as well as merging and splitting behavior in 3D over time. In particular a space time cube approach is highlighted along with statistical analysis. Furthermore a <span class="hlt">lightning</span> cell nowcasting is conducted and visualized. The idea thereby is to predict the following cell features for the next 10-60 minutes including location, centre, extension, density, area, volume, lifetime and cell feature probabilities. The main focus will be set to a suitable interactive visualization of the predicted featured within the GUI. The developed visual</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080013550&hterms=Geostationary&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DGeostationary','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080013550&hterms=Geostationary&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DGeostationary"><span>Geostationary <span class="hlt">Lightning</span> Mapper for GOES-R and Beyond</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodman, Steven J.; Blakeslee, R. J.; Koshak, W.</p> <p>2008-01-01</p> <p>The Geostationary <span class="hlt">Lightning</span> Mapper (GLM) is a single channel, near-IR imager/optical transient event detector, used to detect, locate and measure total <span class="hlt">lightning</span> activity over the full-disk as part of a 3-axis stabilized, geostationary weather satellite system. The next generation NOAA Geostationary Operational Environmental Satellite (GOES-R) series with a planned launch readiness in December 2014 will carry a GLM that will provide continuous day and night observations of <span class="hlt">lightning</span> from the west coast of Africa (GOES-E) to New Zealand (GOES-W) when the constellation is fUlly operational. The mission objectives for the GLM are to 1) provide continuous, full-disk <span class="hlt">lightning</span> measurements for storm warning and nowcasting, 2) provide early warning of tornadic activity, and 3) accumulate a long-term database to track decadal changes of <span class="hlt">lightning</span>. The GLM owes its heritage to the NASA <span class="hlt">Lightning</span> Imaging Sensor (1997-Present) and the Optical Transient Detector (1995-2000), which were developed for the Earth Observing System and have produced a combined 13 year data record of global <span class="hlt">lightning</span> activity. Instrument formulation studies were completed in March 2007 and the implementation phase to develop a prototype model and up to four flight models will be underway in the latter part of 2007. In parallel with the instrument development, a GOES-R Risk Reduction Team and Algorithm Working Group <span class="hlt">Lightning</span> Applications Team have begun to develop the Level 2 algorithms and applications. Proxy total <span class="hlt">lightning</span> data from the NASA <span class="hlt">Lightning</span> Imaging Sensor on the Tropical Rainfall Measuring Mission (TRMM) satellite and regional test beds (e.g., <span class="hlt">Lightning</span> Mapping Arrays in North Alabama and the Washington DC Metropolitan area) are being used to develop the pre-launch algorithms and applications, and also improve our knowledge of thunderstorm initiation and evolution. Real time <span class="hlt">lightning</span> mapping data are being provided in an experimental mode to selected National Weather Service (NWS</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/949855-lightning-vulnerability-fiber-optic-cables','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/949855-lightning-vulnerability-fiber-optic-cables"><span><span class="hlt">Lightning</span> vulnerability of fiber-optic cables.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Martinez, Leonard E.; Caldwell, Michele</p> <p>2008-06-01</p> <p>One reason to use optical fibers to transmit data is for isolation from unintended electrical energy. Using fiber optics in an application where the fiber cable/system penetrates the aperture of a grounded enclosure serves two purposes: first, it allows for control signals to be transmitted where they are required, and second, the insulating properties of the fiber system help to electrically isolate the fiber terminations on the inside of the grounded enclosure. A fundamental question is whether fiber optic cables can allow electrical energy to pass through a grounded enclosure, with a <span class="hlt">lightning</span> strike representing an extreme but very importantmore » case. A DC test bed capable of producing voltages up to 200 kV was used to characterize electrical properties of a variety of fiber optic cable samples. Leakage current in the samples were measured with a micro-Ammeter. In addition to the leakage current measurements, samples were also tested to DC voltage breakdown. After the fiber optic cables samples were tested with DC methods, they were tested under representative <span class="hlt">lightning</span> conditions at the Sandia <span class="hlt">Lightning</span> Simulator (SLS). Simulated <span class="hlt">lightning</span> currents of 30 kA and 200 kA were selected for this test series. This paper documents measurement methods and test results for DC high voltage and simulated <span class="hlt">lightning</span> tests performed at the Sandia <span class="hlt">Lightning</span> Simulator on fiber optic cables. The tests performed at the SLS evaluated whether electrical energy can be conducted inside or along the surface of a fiber optic cable into a grounded enclosure under representative <span class="hlt">lightning</span> conditions.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=336118&keyword=air&subject=air%20research&showcriteria=2&fed_org_id=111&datebeginpublishedpresented=09/03/2012&dateendpublishedpresented=09/03/2017&sortby=pubdateyear','PESTICIDES'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=336118&keyword=air&subject=air%20research&showcriteria=2&fed_org_id=111&datebeginpublishedpresented=09/03/2012&dateendpublishedpresented=09/03/2017&sortby=pubdateyear"><span>A simple <span class="hlt">lightning</span> assimilation technique for improving ...</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>Convective rainfall is often a large source of error in retrospective modeling applications. In particular, positive rainfall biases commonly exist during summer months due to overactive convective parameterizations. In this study, <span class="hlt">lightning</span> assimilation was applied in the Kain-Fritsch (KF) convective scheme to improve retrospective simulations using the Weather Research and Forecasting (WRF) model. The assimilation method has a straightforward approach: force KF deep convection where <span class="hlt">lightning</span> is observed and, optionally, suppress deep convection where <span class="hlt">lightning</span> is absent. WRF simulations were made with and without <span class="hlt">lightning</span> assimilation over the continental United States for July 2012, July 2013, and January 2013. The simulations were evaluated against NCEP stage-IV precipitation data and MADIS near-surface meteorological observations. In general, the use of <span class="hlt">lightning</span> assimilation considerably improves the simulation of summertime rainfall. For example, the July 2012 monthly averaged bias of 6 h accumulated rainfall is reduced from 0.54 to 0.07 mm and the spatial correlation is increased from 0.21 to 0.43 when <span class="hlt">lightning</span> assimilation is used. Statistical measures of near-surface meteorological variables also are improved. Consistent improvements also are seen for the July 2013 case. These results suggest that this <span class="hlt">lightning</span> assimilation technique has the potential to substantially improve simulation of warm-season rainfall in retrospective WRF applications. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=325491&keyword=air&subject=air%20research&showcriteria=2&fed_org_id=111&datebeginpublishedpresented=02/27/2012&dateendpublishedpresented=02/27/2017&sortby=pubdateyear','PESTICIDES'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=325491&keyword=air&subject=air%20research&showcriteria=2&fed_org_id=111&datebeginpublishedpresented=02/27/2012&dateendpublishedpresented=02/27/2017&sortby=pubdateyear"><span>A Simple <span class="hlt">Lightning</span> Assimilation Technique For Improving ...</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>Convective rainfall is often a large source of error in retrospective modeling applications. In particular, positive rainfall biases commonly exist during summer months due to overactive convective parameterizations. In this study, <span class="hlt">lightning</span> assimilation was applied in the Kain-Fritsch (KF) convective scheme to improve retrospective simulations using the Weather Research and Forecasting (WRF) model. The assimilation method has a straightforward approach: Force KF deep convection where <span class="hlt">lightning</span> is observed and, optionally, suppress deep convection where <span class="hlt">lightning</span> is absent. WRF simulations were made with and without <span class="hlt">lightning</span> assimilation over the continental United States for July 2012, July 2013, and January 2013. The simulations were evaluated against NCEP stage-IV precipitation data and MADIS near-surface meteorological observations. In general, the use of <span class="hlt">lightning</span> assimilation considerably improves the simulation of summertime rainfall. For example, the July 2012 monthly-averaged bias of 6-h accumulated rainfall is reduced from 0.54 mm to 0.07 mm and the spatial correlation is increased from 0.21 to 0.43 when <span class="hlt">lightning</span> assimilation is used. Statistical measures of near-surface meteorological variables also are improved. Consistent improvements also are seen for the July 2013 case. These results suggest that this <span class="hlt">lightning</span> assimilation technique has the potential to substantially improve simulation of warm-season rainfall in retrospective WRF appli</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009pcms.confE..98P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009pcms.confE..98P"><span>Relationship between convective precipitation and <span class="hlt">lightning</span> activity using radar quantitative precipitation estimates and total <span class="hlt">lightning</span> data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pineda, N.; Rigo, T.; Bech, J.; Argemí, O.</p> <p>2009-09-01</p> <p>Thunderstorms can be characterized by both rainfall and <span class="hlt">lightning</span>. The relationship between convective precipitation and <span class="hlt">lightning</span> activity may be used as an indicator of the rainfall regime. Besides, a better knowledge of local thunderstorm phenomenology can be very useful to assess weather surveillance tasks. Two types of approach can be distinguished in the bibliography when analyzing the rainfall and <span class="hlt">lightning</span> activity. On one hand, rain yields (ratio of rain mass to cloud-to-ground flash over a common area) calculated for long temporal and spatial domains and using rain-gauge records to estimate the amounts of precipitation. On the other hand, a case-by-case approach has been used in many studies to analyze the relationship between convective precipitation and <span class="hlt">lightning</span> in individual storms, using weather radar data to estimate rainfall volumes. Considering a local thunderstorm case study approach, the relation between rainfall and <span class="hlt">lightning</span> is usually quantified as the Rainfall-<span class="hlt">Lightning</span> ratio (RLR). This ratio estimates the convective rainfall volume per <span class="hlt">lightning</span> flash. Intense storms tend to produce lower RLR values than moderate storms, but the range of RLR found in diverse studies is quite wide. This relationship depends on thunderstorm type, local climatology, convective regime, type of <span class="hlt">lightning</span> flashes considered, oceanic and continental storms, etc. The objective of this paper is to analyze the relationship between convective precipitation and <span class="hlt">lightning</span> in a case-by-case approach, by means of daily radar-derived quantitative precipitation estimates (QPE) and total <span class="hlt">lightning</span> data, obtained from observations of the Servei Meteorològic de Catalunya remote sensing systems, which covers an area of approximately 50000 km2 in the NE of the Iberian Peninsula. The analyzed dataset is composed by 45 thunderstorm days from April to October 2008. A good daily correlation has been found between the radar QPE and the CG flash counts (best linear fit with a R^2</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.loc.gov/pictures/collection/hh/item/ca2594.photos.382580p/','SCIGOV-HHH'); return false;" href="https://www.loc.gov/pictures/collection/hh/item/ca2594.photos.382580p/"><span>17. DETAIL, FOURTEENINCH LIQUID OXYGEN <span class="hlt">BALL</span> VALVE. Looking south southeast. ...</span></a></p> <p><a target="_blank" href="http://www.loc.gov/pictures/collection/hh/">Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey</a></p> <p></p> <p></p> <p>17. DETAIL, FOURTEEN-INCH LIQUID OXYGEN <span class="hlt">BALL</span> VALVE. Looking south southeast. - Edwards Air Force Base, Air Force Rocket Propulsion <span class="hlt">Laboratory</span>, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19740020845','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19740020845"><span>Fatigue life of high-speed <span class="hlt">ball</span> bearings with silicon nitride <span class="hlt">balls</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Parker, R. J.; Zaretsky, E. V.</p> <p>1974-01-01</p> <p>Hot-pressed silicon nitride was evaluated as a rolling-element bearing material. The five-<span class="hlt">ball</span> fatigue tester was used to test 12.7-mm- diameter silicon nitride <span class="hlt">balls</span> at maximum Hertz stresses ranging from 4.27 x 10 to the 9th power n/sq m to 6.21 x 10 to the 9th power n/sq m at a race temperature of 328K. The fatigue life of NC-132 hot-pressed silicon nitride was found to be equal to typical bearing steels and much greater than other ceramic or cermet materials at the same stress levels. A digital computer program was used to predict the fatigue life of 120-mm- bore angular-contact <span class="hlt">ball</span> bearings containing either steel or silicon nitride <span class="hlt">balls</span>. The analysis indicates that there is no improvement in the lives of bearings of the same geometry operating at DN values from 2 to 4 million where silicon nitride <span class="hlt">balls</span> are used in place of steel <span class="hlt">balls</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5677374','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5677374"><span>Assessing <span class="hlt">Lightning</span> and Wildfire Hazard by Land Properties and Cloud to Ground <span class="hlt">Lightning</span> Data with Association Rule Mining in Alberta, Canada</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cha, DongHwan; Wang, Xin; Kim, Jeong Woo</p> <p>2017-01-01</p> <p>Hotspot analysis was implemented to find regions in the province of Alberta (Canada) with high frequency Cloud to Ground (CG) <span class="hlt">lightning</span> strikes clustered together. Generally, hotspot regions are located in the central, central east, and south central regions of the study region. About 94% of annual <span class="hlt">lightning</span> occurred during warm months (June to August) and the daily <span class="hlt">lightning</span> frequency was influenced by the diurnal heating cycle. The association rule mining technique was used to investigate frequent CG <span class="hlt">lightning</span> patterns, which were verified by similarity measurement to check the patterns’ consistency. The similarity coefficient values indicated that there were high correlations throughout the entire study period. Most wildfires (about 93%) in Alberta occurred in forests, wetland forests, and wetland shrub areas. It was also found that <span class="hlt">lightning</span> and wildfires occur in two distinct areas: frequent wildfire regions with a high frequency of <span class="hlt">lightning</span>, and frequent wild-fire regions with a low frequency of <span class="hlt">lightning</span>. Further, the preference index (PI) revealed locations where the wildfires occurred more frequently than in other class regions. The wildfire hazard area was estimated with the CG <span class="hlt">lightning</span> hazard map and specific land use types. PMID:29065564</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29065564','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29065564"><span>Assessing <span class="hlt">Lightning</span> and Wildfire Hazard by Land Properties and Cloud to Ground <span class="hlt">Lightning</span> Data with Association Rule Mining in Alberta, Canada.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cha, DongHwan; Wang, Xin; Kim, Jeong Woo</p> <p>2017-10-23</p> <p>Hotspot analysis was implemented to find regions in the province of Alberta (Canada) with high frequency Cloud to Ground (CG) <span class="hlt">lightning</span> strikes clustered together. Generally, hotspot regions are located in the central, central east, and south central regions of the study region. About 94% of annual <span class="hlt">lightning</span> occurred during warm months (June to August) and the daily <span class="hlt">lightning</span> frequency was influenced by the diurnal heating cycle. The association rule mining technique was used to investigate frequent CG <span class="hlt">lightning</span> patterns, which were verified by similarity measurement to check the patterns' consistency. The similarity coefficient values indicated that there were high correlations throughout the entire study period. Most wildfires (about 93%) in Alberta occurred in forests, wetland forests, and wetland shrub areas. It was also found that <span class="hlt">lightning</span> and wildfires occur in two distinct areas: frequent wildfire regions with a high frequency of <span class="hlt">lightning</span>, and frequent wild-fire regions with a low frequency of <span class="hlt">lightning</span>. Further, the preference index (PI) revealed locations where the wildfires occurred more frequently than in other class regions. The wildfire hazard area was estimated with the CG <span class="hlt">lightning</span> hazard map and specific land use types.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Natur.558...87B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Natur.558...87B"><span>Prevalent <span class="hlt">lightning</span> sferics at 600 megahertz near Jupiter's poles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brown, Shannon; Janssen, Michael; Adumitroaie, Virgil; Atreya, Sushil; Bolton, Scott; Gulkis, Samuel; Ingersoll, Andrew; Levin, Steven; Li, Cheng; Li, Liming; Lunine, Jonathan; Misra, Sidharth; Orton, Glenn; Steffes, Paul; Tabataba-Vakili, Fachreddin; Kolmašová, Ivana; Imai, Masafumi; Santolík, Ondřej; Kurth, William; Hospodarsky, George; Gurnett, Donald; Connerney, John</p> <p>2018-06-01</p> <p><span class="hlt">Lightning</span> has been detected on Jupiter by all visiting spacecraft through night-side optical imaging and whistler (<span class="hlt">lightning</span>-generated radio waves) signatures1-6. Jovian <span class="hlt">lightning</span> is thought to be generated in the mixed-phase (liquid-ice) region of convective water clouds through a charge-separation process between condensed liquid water and water-ice particles, similar to that of terrestrial (cloud-to-cloud) <span class="hlt">lightning</span>7-9. Unlike terrestrial <span class="hlt">lightning</span>, which emits broadly over the radio spectrum up to gigahertz frequencies10,11, <span class="hlt">lightning</span> on Jupiter has been detected only at kilohertz frequencies, despite a search for signals in the megahertz range12. Strong ionospheric attenuation or a <span class="hlt">lightning</span> discharge much slower than that on Earth have been suggested as possible explanations for this discrepancy13,14. Here we report observations of Jovian <span class="hlt">lightning</span> sferics (broadband electromagnetic impulses) at 600 megahertz from the Microwave Radiometer15 onboard the Juno spacecraft. These detections imply that Jovian <span class="hlt">lightning</span> discharges are not distinct from terrestrial <span class="hlt">lightning</span>, as previously thought. In the first eight orbits of Juno, we detected 377 <span class="hlt">lightning</span> sferics from pole to pole. We found <span class="hlt">lightning</span> to be prevalent in the polar regions, absent near the equator, and most frequent in the northern hemisphere, at latitudes higher than 40 degrees north. Because the distribution of <span class="hlt">lightning</span> is a proxy for moist convective activity, which is thought to be an important source of outward energy transport from the interior of the planet16,17, increased convection towards the poles could indicate an outward internal heat flux that is preferentially weighted towards the poles9,16,18. The distribution of moist convection is important for understanding the composition, general circulation and energy transport on Jupiter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/890612','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/890612"><span><span class="hlt">Lightning</span> Protection System for HE Facilities at LLNL - Certification Template</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Clancy, T J; Ong, M M; Brown, C G</p> <p>2005-12-08</p> <p>This document is meant as a template to assist in the development of your own lighting certification process. Aside from this introduction and the mock representative name of the building (Building A), this document is nearly identical to a <span class="hlt">lightning</span> certification report issued by the Engineering Directorate at Lawrence Livermore National <span class="hlt">Laboratory</span>. At the date of this release, we have certified over 70 HE processing and storage cells at our Site 300 facilities. In Chapters 1 and 2 respectively, we address the need and methods of <span class="hlt">lightning</span> certification for HE processing and storage facilities at LLNL. We present the preferredmore » method of <span class="hlt">lightning</span> protection in Chapter 3, as well as the likely building modifications that are needed to comply with this method. In Chapter 4, we present the threat assessment and resulting safe work areas within a cell. After certification, there may be changes to operations during a <span class="hlt">lightning</span> alert, and this is discussed in Chapter 5. Chapter 6 lists the maintenance requirements for the continuation of lighting certification status. Appendices of this document are meant as an aid in developing your own certification process, and they include a bonding list, an inventory of measurement equipment, surge suppressors in use at LLNL, an Integrated Work and Safety form (IWS), and a template certification sign-off sheet. The <span class="hlt">lightning</span> certification process involves more that what is spelled out in this document. The first steps involve considerable planning, the securing of funds, and management and explosives safety buy-in. Permits must be obtained, measurement equipment must be assembled and tested, and engineers and technicians must be trained in their use. Cursory building inspections are also recommended, and surge suppression for power systems must be addressed. Upon completion of a certification report and its sign-off by management, additional work is required. Training will be needed in order to educate workers and facility</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130012450','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130012450"><span>Comparison of the KSC-ER Cloud-to-Ground <span class="hlt">Lightning</span> Surveillance System (CGLSS) and the U.S. National <span class="hlt">Lightning</span> Detection Network (NLDN)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ward, Jennifer G.; Cummins, Kenneth L.; Krider, E. Philip</p> <p>2008-01-01</p> <p>The NASA Kennedy Space Center (KSC) and Air Force Eastern Range (ER) are located in a region of Florida that experiences the highest area density of <span class="hlt">lightning</span> strikes to ground in the United States, with values approaching 16 fl/km 2/yr when accumulated in 10x10 km (100 sq km) grids (see Figure 1). Consequently, the KSC-ER use data derived from two cloud-to-ground (CG) <span class="hlt">lightning</span> detection networks to detect hazardous weather, the "Cloud-to-Ground <span class="hlt">Lightning</span> Surveillance System" (CGLSS) that is owned and operated by the Air Force and the U.S. National <span class="hlt">Lightning</span> Detection Network (NLDN) that is owned and operated by Vaisala, Inc. These systems are used to provide <span class="hlt">lightning</span> warnings for ground operations and to insure mission safety during space launches at the KSC-ER. In order to protect the rocket and shuttle fleets, NASA and the Air Force follow a set of <span class="hlt">lightning</span> safety guidelines that are called the <span class="hlt">Lightning</span> Launch Commit Criteria (LLCC). These rules are designed to insure that vehicles are not exposed to the hazards of natural or triggered <span class="hlt">lightning</span> that would in any way jeopardize a mission or cause harm to the shuttle astronauts. Also, if any CG <span class="hlt">lightning</span> strikes too close to a vehicle on a launch pad, it can cause time-consuming mission delays due to the extensive retests that are often required for vehicles and/or payloads when this occurs. If any CG <span class="hlt">lightning</span> strike is missed or mis-located by even a small amount, the result could have significant safety implications, require expensive retests, or create unnecessary delays or scrubs in launches. Therefore, it is important to understand the performance of each <span class="hlt">lightning</span> detection system in considerable detail.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100026543','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100026543"><span>Recent Advancements in <span class="hlt">Lightning</span> Jump Algorithm Work</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schultz, Christopher J.; Petersen, Walter A.; Carey, Lawrence D.</p> <p>2010-01-01</p> <p>In the past year, the primary objectives were to show the usefulness of total <span class="hlt">lightning</span> as compared to traditional cloud-to-ground (CG) networks, test the <span class="hlt">lightning</span> jump algorithm configurations in other regions of the country, increase the number of thunderstorms within our thunderstorm database, and to pinpoint environments that could prove difficult for any <span class="hlt">lightning</span> jump configuration. A total of 561 thunderstorms have been examined in the past year (409 non-severe, 152 severe) from four regions of the country (North Alabama, Washington D.C., High Plains of CO/KS, and Oklahoma). Results continue to indicate that the 2 <span class="hlt">lightning</span> jump algorithm configuration holds the most promise in terms of prospective operational <span class="hlt">lightning</span> jump algorithms, with a probability of detection (POD) at 81%, a false alarm rate (FAR) of 45%, a critical success index (CSI) of 49% and a Heidke Skill Score (HSS) of 0.66. The second best performing algorithm configuration was the Threshold 4 algorithm, which had a POD of 72%, FAR of 51%, a CSI of 41% and an HSS of 0.58. Because a more complex algorithm configuration shows the most promise in terms of prospective operational <span class="hlt">lightning</span> jump algorithms, accurate thunderstorm cell tracking work must be undertaken to track <span class="hlt">lightning</span> trends on an individual thunderstorm basis over time. While these numbers for the 2 configuration are impressive, the algorithm does have its weaknesses. Specifically, low-topped and tropical cyclone thunderstorm environments are present issues for the 2 <span class="hlt">lightning</span> jump algorithm, because of the suppressed vertical depth impact on overall flash counts (i.e., a relative dearth in <span class="hlt">lightning</span>). For example, in a sample of 120 thunderstorms from northern Alabama that contained 72 missed events by the 2 algorithm 36% of the misses were associated with these two environments (17 storms).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1817550D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1817550D"><span>Learning from concurrent <span class="hlt">Lightning</span> Imaging Sensor and <span class="hlt">Lightning</span> Mapping Array observations in preparation for the MTG-LI mission</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Defer, Eric; Bovalo, Christophe; Coquillat, Sylvain; Pinty, Jean-Pierre; Farges, Thomas; Krehbiel, Paul; Rison, William</p> <p>2016-04-01</p> <p>The upcoming decade will see the deployment and the operation of French, European and American space-based missions dedicated to the detection and the characterization of the <span class="hlt">lightning</span> activity on Earth. For instance the Tool for the Analysis of Radiation from <span class="hlt">lightNIng</span> and Sprites (TARANIS) mission, with an expected launch in 2018, is a CNES mission dedicated to the study of impulsive energy transfers between the atmosphere of the Earth and the space environment. It will carry a package of Micro Cameras and Photometers (MCP) to detect and locate <span class="hlt">lightning</span> flashes and triggered Transient Luminous Events (TLEs). At the European level, the Meteosat Third Generation Imager (MTG-I) satellites will carry in 2019 the <span class="hlt">Lightning</span> Imager (LI) aimed at detecting and locating the <span class="hlt">lightning</span> activity over almost the full disk of Earth as usually observed with Meteosat geostationary infrared/visible imagers. The American community plans to operate a similar instrument on the GOES-R mission for an effective operation in early 2016. In addition NASA will install in 2016 on the International Space Station the spare version of the <span class="hlt">Lightning</span> Imaging Sensor (LIS) that has proved its capability to optically detect the tropical <span class="hlt">lightning</span> activity from the Tropical Rainfall Measuring Mission (TRMM) spacecraft. We will present concurrent observations recorded by the optical space-borne <span class="hlt">Lightning</span> Imaging Sensor (LIS) and the ground-based Very High Frequency (VHF) <span class="hlt">Lightning</span> Mapping Array (LMA) for different types of <span class="hlt">lightning</span> flashes. The properties of the cloud environment will also be considered in the analysis thanks to coincident observations of the different TRMM cloud sensors. The characteristics of the optical signal will be discussed according to the nature of the parent flash components and the cloud properties. This study should provide some insights not only on the expected optical signal that will be recorded by LI, but also on the definition of the validation strategy of LI, and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170001583','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170001583"><span>Rationales for the <span class="hlt">Lightning</span> Launch Commit Criteria</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Willett, John C. (Editor); Merceret, Francis J. (Editor); Krider, E. Philip; O'Brien, T. Paul; Dye, James E.; Walterscheid, Richard L.; Stolzenburg, Maribeth; Cummins, Kenneth; Christian, Hugh J.; Madura, John T.</p> <p>2016-01-01</p> <p>Since natural and triggered <span class="hlt">lightning</span> are demonstrated hazards to launch vehicles, payloads, and spacecraft, NASA and the Department of Defense (DoD) follow the <span class="hlt">Lightning</span> Launch Commit Criteria (LLCC) for launches from Federal Ranges. The LLCC were developed to prevent future instances of a rocket intercepting natural <span class="hlt">lightning</span> or triggering a <span class="hlt">lightning</span> flash during launch from a Federal Range. NASA and DoD utilize the <span class="hlt">Lightning</span> Advisory Panel (LAP) to establish and develop robust rationale from which the criteria originate. The rationale document also contains appendices that provide additional scientific background, including detailed descriptions of the theory and observations behind the rationales. The LLCC in whole or part are used across the globe due to the rigor of the documented criteria and associated rationale. The Federal Aviation Administration (FAA) adopted the LLCC in 2006 for commercial space transportation and the criteria were codified in the FAA's Code of Federal Regulations (CFR) for Safety of an Expendable Launch Vehicle (Appendix G to 14 CFR Part 417, (G417)) and renamed <span class="hlt">Lightning</span> Flight Commit Criteria in G417.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMAE13A0368Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMAE13A0368Z"><span>Statistical Evolution of the <span class="hlt">Lightning</span> Flash</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zoghzoghy, F. G.; Cohen, M.; Said, R.; Inan, U. S.</p> <p>2012-12-01</p> <p>Natural <span class="hlt">lightning</span> is one of the most fascinating and powerful electrical processes on Earth. To date, the physics behind this natural phenomenon are not fully understood, due primarily to the difficulty of obtaining measurements inside thunderstorms and to the wide range of timescales involved (from nanoseconds to seconds). Our aim is to use accurate <span class="hlt">lightning</span> geo-location data from the National <span class="hlt">Lightning</span> Detection Network (NLDN) to study statistical patterns in <span class="hlt">lightning</span>, taking advantage of the fact that millions of <span class="hlt">lightning</span> flashes occur around the globe every day. We present two sets of results, one involving the patterns of flashes in a storm, and a second involving the patterns of strokes in a flash. These patterns can provide a surrogate measure of the timescales and the spatial extents of the underlying physical processes. First, we study the timescales of charge buildup inside thunderstorms. We find that, following a <span class="hlt">lightning</span> flash, the probability of another neighboring flash decreases and takes tens of seconds to recover. We find that this suppression effect is a function of flash type, stroke peak current, cloud-to-ground (CG) stroke multiplicity, and other <span class="hlt">lightning</span> and geographical parameters. We find that the probabilities of subsequent flashes are more suppressed following oceanic <span class="hlt">lightning</span>, or following flashes with higher peak currents and/or higher multiplicities (for CG flashes). Second, we use NLDN data to study the evolution of the strokes within a CG flash. A CG flash typically includes multiple return strokes, which can occur in the same channel or in multiple channels within a few kilometers. We cluster NLDN stroke data into flashes and produce the probability density function of subsequent strokes as a function of distance and time-delays relative to the previous stroke. Using this technique, we investigate processes which occur during the CG <span class="hlt">lightning</span> flash with nanosecond to millisecond timescales. For instance, our results suggest</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMAE22B..04W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMAE22B..04W"><span>a review and an update on the winter <span class="hlt">lightning</span> that occurred on a rotating windmill and its standalone <span class="hlt">lightning</span> protection tower</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, D.; Takagi, N.</p> <p>2012-12-01</p> <p>We have observed the <span class="hlt">lightning</span> occurred on a 100 m high windmill and its 105 m high standalone <span class="hlt">lightning</span>-protection tower about 45 m separated from the windmill in the Hokuriku area of Japan for 7 consecutive winter seasons from 2005 to 2012. Our main observation items include: (1) <span class="hlt">Lightning</span> current at the bottom of both the windmill and the tower. (2) Thunderstorm electric fields and the electric field changes caused by <span class="hlt">lightning</span> at multiple sites. (3) Optical images by both low and high speed imaging systems. During the 7 winter seasons, over 100 <span class="hlt">lightning</span> have hit either the tower or the windmill or both. All the <span class="hlt">lightning</span> but two observed are of upward <span class="hlt">lightning</span>. Those upward <span class="hlt">lightning</span> can be sub-classified into self-initiated types and other-triggered types according to whether there is a discharge activity prior to the upward leaders or not. Self-initiated and other-triggered upward <span class="hlt">lightning</span> tend to have biased percentages in terms of striking locations (windmill versus tower) and thunderstorm types (active versus weak). All the upward <span class="hlt">lightning</span> but one contained only initial continuous current stages. In the presentation, we will first give a review on those results we have reported before [1-3]. As an update, we will report the following results. (1) The electric field change required for triggering a negative upward leader is usually more than twice bigger than that for triggering a positive upward leader. (2) An electric current pulse with an amplitude of several tens of Amperes along a high structure has been observed to occur in response to a rapid electric change generated by either a nearby return stroke or K-change. References [1] D.Wang, N.Takagi, T.Watanebe, H. Sakurano, M. Hashimoto, Observed characteristics of upward leaders that are initiated from a windmill and its <span class="hlt">lightning</span> protection tower, Geophys. Res. Lett., Vol.35, L02803, doi:10.1029/2007GL032136, 2008. [2] W. Lu, D.Wang, Y. Zhang and N. Takagi, Two associated upward <span class="hlt">lightning</span> flashes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.loc.gov/pictures/collection/hh/item/ca2594.photos.382579p/','SCIGOV-HHH'); return false;" href="https://www.loc.gov/pictures/collection/hh/item/ca2594.photos.382579p/"><span>16. DETAIL SHOWING LIQUID OXYGEN TANK FOURTEENINCH <span class="hlt">BALL</span> VALVE. Looking ...</span></a></p> <p><a target="_blank" href="http://www.loc.gov/pictures/collection/hh/">Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey</a></p> <p></p> <p></p> <p>16. DETAIL SHOWING LIQUID OXYGEN TANK FOURTEEN-INCH <span class="hlt">BALL</span> VALVE. Looking southwest. - Edwards Air Force Base, Air Force Rocket Propulsion <span class="hlt">Laboratory</span>, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840035732&hterms=Electromagnetic+Pulse&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DElectromagnetic%2BPulse','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840035732&hterms=Electromagnetic+Pulse&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DElectromagnetic%2BPulse"><span>Analysis of electromagnetic fields on an F-106B aircraft during <span class="hlt">lightning</span> strikes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Trost, T. F.; Pitts, F. L.</p> <p>1982-01-01</p> <p>Information on the exterior electromagnetic environment of an aircraft when it is struck by <span class="hlt">lightning</span> has been obtained during thunderstorm penetrations with an F-106B aircraft. Electric and magnetic fields were observed, using mainly time-derivative type sensors, with bandwidths to 50 MHz. <span class="hlt">Lightning</span> pulse lengths ranging from 25 ns to 7 microsec have been recorded. Sufficient high-frequency content was present to excite electromagnetic resonances of the aircraft, and peaks in the frequency spectra of the waveforms in the range 7 to 23 MHz are in agreement with the resonant frequencies determined in <span class="hlt">laboratory</span> scale-model tests. Both positively and negatively charged strikes were experienced, and most of the data suggest low values of peak current.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMAE31A0422S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMAE31A0422S"><span>Multi-mode Observations of Cloud-to-Ground <span class="hlt">Lightning</span> Strokes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Smith, M. W.; Smith, B. J.; Clemenson, M. D.; Zollweg, J. D.</p> <p>2015-12-01</p> <p>We present hyper-temporal and hyper-spectral data collected using a suite of three Phantom high-speed cameras configured to observe cloud-to-ground <span class="hlt">lightning</span> strokes. The first camera functioned as a contextual imager to show the location and structure of the strokes. The other two cameras were operated as slit-less spectrometers, with resolutions of 0.2 to 1.0 nm. The imaging camera was operated at a readout rate of 48,000 frames per second and provided an image-based trigger mechanism for the spectrometers. Each spectrometer operated at a readout rate of 400,000 frames per second. The sensors were deployed on the southern edge of Albuquerque, New Mexico and collected data over a 4 week period during the thunderstorm season in the summer of 2015. Strikes observed by the sensor suite were correlated to specific strikes recorded by the National <span class="hlt">Lightning</span> Data Network (NLDN) and thereby geo-located. Sensor calibration factors, distance to each strike, and calculated values of atmospheric transmission were used to estimate absolute radiometric intensities for the spectral-temporal data. The data that we present show the intensity and time evolution of broadband and line emission features for both leader and return strokes. We highlight several key features and overall statistics of the observations. A companion poster describes a <span class="hlt">lightning</span> model that is being developed at Sandia National <span class="hlt">Laboratories</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=MSFC-9800760&hterms=golf&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dgolf','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=MSFC-9800760&hterms=golf&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dgolf"><span>Golf <span class="hlt">Ball</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1998-01-01</p> <p>The Ultra 500 Series golf <span class="hlt">balls</span>, introduced in 1995 by Wilson Sporting Goods Company, has 500 dimples arranged in a pattern of 60 spherical triangles. The design employs NASA's aerodynamics technology analysis of air loads of the tank and Shuttle orbiter that was performed under the Space Shuttle External Tank program. According to Wilson, this technology provides 'the most symmetrical <span class="hlt">ball</span> surface available, sustaining initial velocity longer and producing the most stable <span class="hlt">ball</span> flight for unmatched accuracy and distance.' The dimples are in three sizes, shapes and depths mathematically positioned for the best effect. The selection of dimples and their placement optimizes the interaction of opposing forces of lift and drag. Large dimples reduce air drag, enhance lift, and maintain spin for distance. Small dimples prevent excessive lift that destabilizes the <span class="hlt">ball</span> flight and the medium size dimples blend the other two.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19830041715&hterms=radiofrequency+measurement&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dradiofrequency%2Bmeasurement','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19830041715&hterms=radiofrequency+measurement&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dradiofrequency%2Bmeasurement"><span><span class="hlt">Lightning</span> activity on Jupiter</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Borucki, W. J.; Bar-Nun, A.; Scarf, F. L.; Look, A. F.; Hunt, G. E.</p> <p>1982-01-01</p> <p>Photographic observations of the nightside of Jupiter by the Voyager 1 spacecraft show the presence of extensive <span class="hlt">lightning</span> activity. Detection of whistlers by the plasma wave analyzer confirms the optical observations and implies that many flashes were not recorded by the Voyager camera because the intensity of the flashes was below the threshold sensitivity of the camera. Measurements of the optical energy radiated per flash indicate that the observed flashes had energies similar to that for terrestrial superbolts. The best estimate of the <span class="hlt">lightning</span> energy dissipation rate of 0.0004 W/sq m was derived from a consideration of the optical and radiofrequency measurements. The ratio of the energy dissipated by <span class="hlt">lightning</span> compared to the convective energy flux is estimated to be between 0.000027 and 0.00005. The terrestrial value is 0.0001.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760013394','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760013394"><span>Effect of <span class="hlt">ball</span> geometry on endurance limit in bending of drilled <span class="hlt">balls</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Munson, H. E.</p> <p>1975-01-01</p> <p>Four designs of drilled (cylindrically hollow) <span class="hlt">balls</span> were tested for resistance to bending fatigue. Bending fatigue has been demonstrated to be a limiting factor in previous evaluations of the drilled <span class="hlt">ball</span> concept. A web reinforced drilled <span class="hlt">ball</span> was most successful in resisting bending fatigue. Another design of through drilled design, involving a heavier wall than the standard reference <span class="hlt">ball</span>, also showed significant improvement in resistance to bending fatigue.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/976585','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/976585"><span>Detection of VHF <span class="hlt">lightning</span> from GPS orbit</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Suszcynsky, D. M.</p> <p>2003-01-01</p> <p>Satellite-based VHF' <span class="hlt">lightning</span> detection is characterized at GPS orbit by using a VHF receiver system recently launched on the GPS SVN 54 satellite. Collected <span class="hlt">lightning</span> triggers consist of Narrow Bipolar Events (80%) and strong negative return strokes (20%). The results are used to evaluate the performance of a future GPS-satellite-based VHF global <span class="hlt">lightning</span> monitor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28770051','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28770051"><span>Quantification and identification of <span class="hlt">lightning</span> damage in tropical forests.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yanoviak, Stephen P; Gora, Evan M; Burchfield, Jeffrey M; Bitzer, Phillip M; Detto, Matteo</p> <p>2017-07-01</p> <p>Accurate estimates of tree mortality are essential for the development of mechanistic forest dynamics models, and for estimating carbon storage and cycling. However, identifying agents of tree mortality is difficult and imprecise. Although <span class="hlt">lightning</span> kills thousands of trees each year and is an important agent of mortality in some forests, the frequency and distribution of <span class="hlt">lightning</span>-caused tree death remain unknown for most forests. Moreover, because all evidence regarding the effects of <span class="hlt">lightning</span> on trees is necessarily anecdotal and post hoc, rigorous tests of hypotheses regarding the ecological effects of <span class="hlt">lightning</span> are impossible. We developed a combined electronic sensor/camera-based system for the location and characterization of <span class="hlt">lightning</span> strikes to the forest canopy in near real time and tested the system in the forest of Barro Colorado Island, Panama. Cameras mounted on towers provided continuous video recordings of the forest canopy that were analyzed to determine the locations of <span class="hlt">lightning</span> strikes. We used a preliminary version of this system to record and locate 18 <span class="hlt">lightning</span> strikes to the forest over a 3-year period. Data from field surveys of known <span class="hlt">lightning</span> strike locations (obtained from the camera system) enabled us to develop a protocol for reliable, ground-based identification of suspected <span class="hlt">lightning</span> damage to tropical trees. In all cases, <span class="hlt">lightning</span> damage was relatively inconspicuous; it would have been overlooked by ground-based observers having no knowledge of the event. We identified three types of evidence that can be used to consistently identify <span class="hlt">lightning</span> strike damage in tropical forests: (1) localized and directionally biased branch mortality associated with flashover among tree and sapling crowns, (2) mortality of lianas or saplings near lianas, and (3) scorched or wilting epiphytic and hemiepiphytic plants. The longitudinal trunk scars that are typical of <span class="hlt">lightning</span>-damaged temperate trees were never observed in this study. Given the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080037560','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080037560"><span>GOES-R Geostationary <span class="hlt">Lightning</span> Mapper Performance Specifications and Algorithms</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mach, Douglas M.; Goodman, Steven J.; Blakeslee, Richard J.; Koshak, William J.; Petersen, William A.; Boldi, Robert A.; Carey, Lawrence D.; Bateman, Monte G.; Buchler, Dennis E.; McCaul, E. William, Jr.</p> <p>2008-01-01</p> <p>The Geostationary <span class="hlt">Lightning</span> Mapper (GLM) is a single channel, near-IR imager/optical transient event detector, used to detect, locate and measure total <span class="hlt">lightning</span> activity over the full-disk. The next generation NOAA Geostationary Operational Environmental Satellite (GOES-R) series will carry a GLM that will provide continuous day and night observations of <span class="hlt">lightning</span>. The mission objectives for the GLM are to: (1) Provide continuous, full-disk <span class="hlt">lightning</span> measurements for storm warning and nowcasting, (2) Provide early warning of tornadic activity, and (2) Accumulate a long-term database to track decadal changes of <span class="hlt">lightning</span>. The GLM owes its heritage to the NASA <span class="hlt">Lightning</span> Imaging Sensor (1997- present) and the Optical Transient Detector (1995-2000), which were developed for the Earth Observing System and have produced a combined 13 year data record of global <span class="hlt">lightning</span> activity. GOES-R Risk Reduction Team and Algorithm Working Group <span class="hlt">Lightning</span> Applications Team have begun to develop the Level 2 algorithms and applications. The science data will consist of <span class="hlt">lightning</span> "events", "groups", and "flashes". The algorithm is being designed to be an efficient user of the computational resources. This may include parallelization of the code and the concept of sub-dividing the GLM FOV into regions to be processed in parallel. Proxy total <span class="hlt">lightning</span> data from the NASA <span class="hlt">Lightning</span> Imaging Sensor on the Tropical Rainfall Measuring Mission (TRMM) satellite and regional test beds (e.g., <span class="hlt">Lightning</span> Mapping Arrays in North Alabama, Oklahoma, Central Florida, and the Washington DC Metropolitan area) are being used to develop the prelaunch algorithms and applications, and also improve our knowledge of thunderstorm initiation and evolution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APh....82...21C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APh....82...21C"><span>Extensive air showers, <span class="hlt">lightning</span>, and thunderstorm ground enhancements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chilingarian, A.; Hovsepyan, G.; Kozliner, L.</p> <p>2016-09-01</p> <p>For <span class="hlt">lightning</span> research, we monitor particle fluxes from thunderclouds, the so-called thunderstorm ground enhancements (TGEs) initiated by runaway electrons, and extensive air showers (EASs) originating from high-energy protons or fully stripped nuclei that enter the Earth's atmosphere. We also monitor the near-surface electric field and atmospheric discharges using a network of electric field mills. The Aragats "electron accelerator" produced several TGEs and <span class="hlt">lightning</span> events in the spring of 2015. Using 1-s time series, we investigated the relationship between <span class="hlt">lightning</span> and particle fluxes. <span class="hlt">Lightning</span> flashes often terminated the particle flux; in particular, during some TGEs, <span class="hlt">lightning</span> events would terminate the particle flux thrice after successive recovery. It was postulated that a <span class="hlt">lightning</span> terminates a particle flux mostly in the beginning of a TGE or in its decay phase; however, we observed two events (19 October 2013 and 20 April 2015) when the huge particle flux was terminated just at the peak of its development. We discuss the possibility of a huge EAS facilitating <span class="hlt">lightning</span> leader to find its path to the ground.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMAE33A2524B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE33A2524B"><span>A first look at <span class="hlt">lightning</span> energy determined from GLM</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bitzer, P. M.; Burchfield, J. C.; Brunner, K. N.</p> <p>2017-12-01</p> <p>The Geostationary <span class="hlt">Lightning</span> Mapper (GLM) was launched in November 2016 onboard GOES-16 has been undergoing post launch and product post launch testing. While these have typically focused on <span class="hlt">lightning</span> metrics such as detection efficiency, false alarm rate, and location accuracy, there are other attributes of the <span class="hlt">lightning</span> discharge that are provided by GLM data. Namely, the optical energy radiated by <span class="hlt">lightning</span> may provide information useful for <span class="hlt">lightning</span> physics and the relationship of <span class="hlt">lightning</span> energy to severe weather development. This work presents initial estimates of the <span class="hlt">lightning</span> optical energy detected by GLM during this initial testing, with a focus on observations during field campaign during spring 2017 in Huntsville. This region is advantageous for the comparison due to the proliferation of ground-based <span class="hlt">lightning</span> instrumentation, including a <span class="hlt">lightning</span> mapping array, interferometer, HAMMA (an array of electric field change meters), high speed video cameras, and several long range VLF networks. In addition, the field campaign included airborne observations of the optical emission and electric field changes. The initial estimates will be compared with previous observations using TRMM-LIS. In addition, a comparison between the operational and scientific GLM data sets will also be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=physics+AND+glass&pg=2&id=EJ984075','ERIC'); return false;" href="https://eric.ed.gov/?q=physics+AND+glass&pg=2&id=EJ984075"><span>Fizz-<span class="hlt">Ball</span> Fizzics</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Moinester, Murray; Gerland, Lars; Liger-Belair, Gerard; Ocherashvili, Aharon</p> <p>2012-01-01</p> <p>We describe the fluid dynamics principles governing the up-down oscillatory cycling of a bubble-covered, low-density, low-mass <span class="hlt">ball</span> of material (referred to henceforth as a "fizz-<span class="hlt">ball</span>") immersed inside a glass of bubbling (super-saturated) carbonated liquid. The bubbles serve to desaturate the liquid of excess CO[subscript 2]. The fizz-<span class="hlt">ball</span> acts…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900005214','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900005214"><span>JPS heater and sensor <span class="hlt">lightning</span> qualification</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cook, M.</p> <p>1989-01-01</p> <p>Simulated <span class="hlt">lightning</span> strike testing of the Redesigned Solid Rocket Motor (RSRM) field joint protection system heater assembly was performed at Thiokol Corp., Wendover <span class="hlt">Lightning</span> Facility. Testing consisted of subjecting the <span class="hlt">lightning</span> evaluation test article to simulated <span class="hlt">lightning</span> strikes and evaluating the effects of heater cable transients on cables within the systems tunnel. The maximum short circuit current coupled onto a United Space Boosters, Inc. operational flight cable within the systems tunnel, induced by transients from all cables external to the systems tunnel, was 92 amperes. The maximum open-circuit voltage coupled was 316 volts. The maximum short circuit current coupled onto a United Space Boosters, Inc. operational flight cable within the systems tunnel, induced by heater power cable transients only, was 2.7 amperes; the maximum open-circuit voltage coupled was 39 volts. All heater power cable induced coupling was due to simulated <span class="hlt">lightning</span> discharges only, no heater operating power was applied during the test. The results showed that, for a worst-case <span class="hlt">lightning</span> discharge, the heater power cable is responsible for a 3.9 decibel increase in voltage coupling to operational flight cables within the systems tunnel. Testing also showed that current and voltage levels coupled onto cables within the systems tunnel are partially dependant on the relative locations of the cables within the systems tunnel.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880019875','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880019875"><span>The 1983 direct strike <span class="hlt">lightning</span> data, part 1</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thomas, Mitchel E.</p> <p>1985-01-01</p> <p>Data waveforms are presented which were obtained during the 1983 direct strike <span class="hlt">lightning</span> tests utilizing the NASA F106-B aircraft specially instrumented for <span class="hlt">lightning</span> electromagnetic measurements. The aircraft was operated in the vicinity of the NASA Langley Research Center, Hampton, Virginia, in a thunderstorm environment to elicit strikes. Electromagnetic field data and conduction currents on the aircraft were recorded for attached <span class="hlt">lightning</span>. Part 1 contains 435 pages of <span class="hlt">lightning</span> strike data in chart form.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880019876','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880019876"><span>The 1983 direct strike <span class="hlt">lightning</span> data, part 2</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thomas, Mitchel E.</p> <p>1985-01-01</p> <p>Data waveforms are presented which were obtained during the 1983 direct strike <span class="hlt">lightning</span> tests utilizing the NASA F106-B aircraft specially instrumented for <span class="hlt">lightning</span> electromagnetic measurements. The aircraft was operated in the vicinity of the NASA Langley Research Center, Hampton, Virginia, in a thunderstorm environment to elicit strikes. Electromagnetic field data and conduction currents on the aircraft were recorded for attached <span class="hlt">lightning</span>. Part 2 contains 443 pages of <span class="hlt">lightning</span> strike data in chart form.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMAE13A0414L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMAE13A0414L"><span>High Speed Video Observations of Natural <span class="hlt">Lightning</span> and Their Implications to Fractal Description of <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, N.; Tilles, J.; Boggs, L.; Bozarth, A.; Rassoul, H.; Riousset, J. A.</p> <p>2016-12-01</p> <p>Recent high speed video observations of triggered and natural <span class="hlt">lightning</span> flashes have significantly advanced our understanding of <span class="hlt">lightning</span> initiation and propagation. For example, they have helped resolve the initiation of <span class="hlt">lightning</span> leaders [Stolzenburg et al., JGR, 119, 12198, 2014; Montanyà et al, Sci. Rep., 5, 15180, 2015], the stepping of negative leaders [Hill et al., JGR, 116, D16117, 2011], the structure of streamer zone around the leader [Gamerota et al., GRL, 42, 1977, 2015], and transient rebrightening processes occurring during the leader propagation [Stolzenburg et al., JGR, 120, 3408, 2015]. We started an observational campaign in the summer of 2016 to study <span class="hlt">lightning</span> by using a Phantom high-speed camera on the campus of Florida Institute of Technology, Melbourne, FL. A few interesting natural cloud-to-ground and intracloud <span class="hlt">lightning</span> discharges have been recorded, including a couple of 8-9 stroke flashes, high peak current flashes, and upward propagating return stroke waves from ground to cloud. The videos show that the propagation of the downward leaders of cloud-to-ground <span class="hlt">lightning</span> discharges is very complex, particularly for the high-peak current flashes. They tend to develop as multiple branches, and each of them splits repeatedly. For some cases, the propagation characteristics of the leader, such as speed, are subject to sudden changes. In this talk, we present several selected cases to show the complexity of the leader propagation. One of the effective approaches to characterize the structure and propagation of <span class="hlt">lightning</span> leaders is the fractal description [Mansell et al., JGR, 107, 4075, 2002; Riousset et al., JGR, 112, D15203, 2007; Riousset et al., JGR, 115, A00E10, 2010]. We also present a detailed analysis of the high-speed images of our observations and formulate useful constraints to the fractal description. Finally, we compare the obtained results with fractal simulations conducted by using the model reported in [Riousset et al., 2007</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19810023007','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19810023007"><span><span class="hlt">Ball</span> Bearing Mechanics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hamrock, Bernard J.; Dowson, Duncan</p> <p>1981-01-01</p> <p>Load-deflection relationships for different types of elliptical contacts such as those found in a <span class="hlt">ball</span> bearing are developed. Simplified expressions that allow quick calculations of deformation to be made simply from a knowledge of the applied load, the material properties, and the geometry of the contacting elements are presented. <span class="hlt">Ball</span> bearings subjected to radial, thrust and combined <span class="hlt">ball</span> loads are analyzed. A design criterion for fatigue life of <span class="hlt">ball</span> bearings is developed. The section of a satisfactory lubricant, as well as describing systems that provide a constant flow of lubricant to the contact, is considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3681151','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3681151"><span><span class="hlt">Lightning</span> Sensors for Observing, Tracking and Nowcasting Severe Weather</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Price, Colin</p> <p>2008-01-01</p> <p>Severe and extreme weather is a major natural hazard all over the world, often resulting in major natural disasters such as hail storms, tornados, wind storms, flash floods, forest fires and <span class="hlt">lightning</span> damages. While precipitation, wind, hail, tornados, turbulence, etc. can only be observed at close distances, <span class="hlt">lightning</span> activity in these damaging storms can be monitored at all spatial scales, from local (using very high frequency [VHF] sensors), to regional (using very low frequency [VLF] sensors), and even global scales (using extremely low frequency [ELF] sensors). Using sensors that detect the radio waves emitted by each <span class="hlt">lightning</span> discharge, it is now possible to observe and track continuously distant thunderstorms using ground networks of sensors. In addition to the number of <span class="hlt">lightning</span> discharges, these sensors can also provide information on <span class="hlt">lightning</span> characteristics such as the ratio between intra-cloud and cloud-to-ground <span class="hlt">lightning</span>, the polarity of the <span class="hlt">lightning</span> discharge, peak currents, charge removal, etc. It has been shown that changes in some of these <span class="hlt">lightning</span> characteristics during thunderstorms are often related to changes in the severity of the storms. In this paper different <span class="hlt">lightning</span> observing systems are described, and a few examples are provided showing how <span class="hlt">lightning</span> may be used to monitor storm hazards around the globe, while also providing the possibility of supplying short term forecasts, called nowcasting. PMID:27879700</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.470..187A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.470..187A"><span><span class="hlt">Lightning</span> chemistry on Earth-like exoplanets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ardaseva, Aleksandra; Rimmer, Paul B.; Waldmann, Ingo; Rocchetto, Marco; Yurchenko, Sergey N.; Helling, Christiane; Tennyson, Jonathan</p> <p>2017-09-01</p> <p>We present a model for <span class="hlt">lightning</span> shock-induced chemistry that can be applied to atmospheres of arbitrary H/C/N/O chemistry, hence for extrasolar planets and brown dwarfs. The model couples hydrodynamics and the STAND2015 kinetic gas-phase chemistry. For an exoplanet analogue to the contemporary Earth, our model predicts NO and NO2 yields in agreement with observation. We predict height-dependent mixing ratios during a storm soon after a <span class="hlt">lightning</span> shock of NO ≈10-3 at 40 km and NO2 ≈10-4 below 40 km, with O3 reduced to trace quantities (≪10-10). For an Earth-like exoplanet with a CO2/N2 dominated atmosphere and with an extremely intense <span class="hlt">lightning</span> storm over its entire surface, we predict significant changes in the amount of NO, NO2, O3, H2O, H2 and predict a significant abundance of C2N. We find that, for the Early Earth, O2 is formed in large quantities by <span class="hlt">lightning</span> but is rapidly processed by the photochemistry, consistent with previous work on <span class="hlt">lightning</span>. The chemical effect of persistent global <span class="hlt">lightning</span> storms are predicted to be significant, primarily due to NO2, with the largest spectral features present at ˜3.4 and ˜6.2 μm. The features within the transmission spectrum are on the order of 1 ppm and therefore are not likely detectable with the James Webb Space Telescope. Depending on its spectral properties, C2N could be a key tracer for <span class="hlt">lightning</span> on Earth-like exoplanets with a N2/CO2 bulk atmosphere, unless destroyed by yet unknown chemical reactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA505293','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA505293"><span><span class="hlt">Lightning</span> Initiation and Propagation</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2009-08-22</p> <p>ray (gamma ray ) and multiple-station (>24) cosmic - ray - muon detection network (TERA) pl:esently in place. Upgrade TERA with LaBr3 detectors to...DATES COVERED 4. TITLE AND SUBTITLE <span class="hlt">Lightning</span> Initistion and Propagation Including the Role of X- Rays , Gamma Rays , and Cosmic Rays 5a... rays , gamma rays , and cosmic rays in the initiation and propagation of <span class="hlt">lightning</span> and in the phenomenology of thunderclouds. The experimental</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA627751','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA627751"><span><span class="hlt">Lightning</span> Injury: A Review</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2008-01-01</p> <p>of <span class="hlt">lightning</span> strike; thus, burn-care providers should be familiar with the character- istics and treatment of these injuries. This paper will review...specific treatment is required [55]. Thermal injury may occur if the patient is wearing metal objects (e.g. zippers), or if clothing ignites [53...Some authors have used intravenous steroids for the treatment of optic-nerve injury in these patients. Other ophthalmologic sequelae of <span class="hlt">lightning</span> injury</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120003618','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120003618"><span>Using Flow Regime <span class="hlt">Lightning</span> and Sounding Climatologies to Initialize Gridded <span class="hlt">Lightning</span> Threat Forecasts for East Central Florida</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lambert, Winifred; Short, David; Wolkmer, Matthew; Sharp, David; Spratt, Scott</p> <p>2006-01-01</p> <p>Each morning, the forecasters at the National Weather Service in Melbourne, FL (NWS MLB) produce an experimental cloud-to-ground (CG) <span class="hlt">lightning</span> threat index map for their county warning area (CWA) that is posted to their web site (http://www.srh.weather.gov/mlb/ghwo/<span class="hlt">lightning</span>.shtml) . Given the hazardous nature of <span class="hlt">lightning</span> in East Central Florida, especially during the warm season months of May September, these maps help users factor the threat of <span class="hlt">lightning</span>, relative to their location, into their daily plans. The maps are color-coded in five levels from Very Low to Extreme, with threat level definitions based on the probability of <span class="hlt">lightning</span> occurrence and the expected amount of CG activity. On a day in which thunderstorms are expected, there are typically two or more threat levels depicted spatially across the CWA. The locations of relative <span class="hlt">lightning</span> threat maxima and minima often depend on the position and orientation of the low-level ridge axis, forecast propagation and interaction of sea/lake/outflow boundaries, expected evolution of moisture and stability fields, and other factors that can influence the spatial distribution of thunderstorms over the CWA. The <span class="hlt">lightning</span> threat index maps are issued for the 24-hour period beginning at 1200 UTC each day with a grid resolution of 5 km x 5 km. Product preparation is performed on the AWIPS Graphical Forecast Editor (GFE), which is the standard NWS platform for graphical editing. Currently, the forecasters create each map manually, starting with a blank map. To improve efficiency of the forecast process, NWS MLB requested that the Applied Meteorology Unit (AMU) create gridded warm season <span class="hlt">lightning</span> climatologies that could be used as first-guess inputs to initialize <span class="hlt">lightning</span> threat index maps. The gridded values requested included CG strike densities and frequency of occurrence stratified by synoptic-scale flow regime. The intent is to improve consistency between forecasters while allowing them to focus on the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130012614','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130012614"><span>Using Flow Regime <span class="hlt">Lightning</span> and Sounding Climatologies to Initialize Gridded <span class="hlt">Lightning</span> Threat Forecasts for East Central Florida</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lambert, Winifred; Short, David; Volkmer, Matthew; Sharp, David; Spratt, Scott</p> <p>2007-01-01</p> <p>Each morning, the forecasters at the National Weather Service in Melbourne, FL (NWS MLB) produce an experimental cloud-to-ground (CG) <span class="hlt">lightning</span> threat index map for their county warning area (CWA) that is posted to their web site (httl://www.srh.weather.gov/mlb/ghwo/<span class="hlt">lightning</span>.shtml) . Given the hazardous nature of <span class="hlt">lightning</span> in East Central Florida, especially during the warm season months of May September, these maps help users factor the threat of <span class="hlt">lightning</span>, relative to their location, into their daily plans. The maps are color-coded in five levels from Very Low to Extreme, with threat level definitions based on the probability of <span class="hlt">lightning</span> occurrence and the expected amount of CG activity. On a day in which thunderstorms are expected, there are typically two or more threat levels depicted spatially across the CWA. The locations of relative <span class="hlt">lightning</span> threat maxima and minima often depend on the position and orientation of the low-level ridge axis, forecast propagation and interaction of sea/lake/outflow boundaries, expected evolution of moisture and stability fields, and other factors that can influence the spatial distribution of thunderstorms over the CWA. The <span class="hlt">lightning</span> threat index maps are issued for the 24-hour period beginning at 1200 UTC each day with a grid resolution of 5 km x 5 km. Product preparation is performed on the AWIPS Graphical Forecast Editor (GFE), which is the standard NWS platform for graphical editing. Until recently, the forecasters created each map manually, starting with a blank map. To improve efficiency of the forecast process, NWS MLB requested that the Applied Meteorology Unit (AMU) create gridded warm season <span class="hlt">lightning</span> climatologies that could be used as first-guess inputs to initialize <span class="hlt">lightning</span> threat index maps. The gridded values requested included CG strike densities and frequency of occurrence stratified by synoptic-scale flow regime. The intent was to improve consistency between forecasters while allowing them to focus on the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130009921','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130009921"><span>Objective <span class="hlt">Lightning</span> Forecasting at Kennedy Space Center and Cape Canaveral Air Force Station using Cloud-to-Ground <span class="hlt">Lightning</span> Surveillance System Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lambert, Winfred; Wheeler, Mark; Roeder, William</p> <p>2005-01-01</p> <p>The 45th Weather Squadron (45 WS) at Cape Canaveral Air-Force Station (CCAFS)ln Florida issues a probability of <span class="hlt">lightning</span> occurrence in their daily 24-hour and weekly planning forecasts. This information is used for general planning of operations at CCAFS and Kennedy Space Center (KSC). These facilities are located in east-central Florida at the east end of a corridor known as '<span class="hlt">Lightning</span> Alley', an indication that <span class="hlt">lightning</span> has a large impact on space-lift operations. Much of the current <span class="hlt">lightning</span> probability forecast is based on a subjective analysis of model and observational data and an objective forecast tool developed over 30 years ago. The 45 WS requested that a new <span class="hlt">lightning</span> probability forecast tool based on statistical analysis of more recent historical warm season (May-September) data be developed in order to increase the objectivity of the daily thunderstorm probability forecast. The resulting tool is a set of statistical <span class="hlt">lightning</span> forecast equations, one for each month of the warm season, that provide a <span class="hlt">lightning</span> occurrence probability for the day by 1100 UTC (0700 EDT) during the warm season.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130012960','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130012960"><span>Situational <span class="hlt">Lightning</span> Climatologies for Central Florida: Phase IV: Central Florida Flow Regime Based Climatologies of <span class="hlt">Lightning</span> Probabilities</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bauman, William H., III</p> <p>2009-01-01</p> <p>The threat of <span class="hlt">lightning</span> is a daily concern during the warm season in Florida. Research has revealed distinct spatial and temporal distributions of <span class="hlt">lightning</span> occurrence that are strongly influenced by large-scale atmospheric flow regimes. Previously, the Applied Meteorology Unit (AMU) calculated the gridded <span class="hlt">lightning</span> climatologies based on seven flow regimes over Florida for 1-, 3- and 6-hr intervals in 5-, 10-, 20-, and 30-NM diameter range rings around the Shuttle Landing Facility (SLF) and eight other airfields in the National Weather Service in Melbourne (NWS MLB) county warning area (CWA). In this update to the work, the AMU recalculated the <span class="hlt">lightning</span> climatologies for using individual <span class="hlt">lightning</span> strike data to improve the accuracy of the climatologies. The AMU included all data regardless of flow regime as one of the stratifications, added monthly stratifications, added three years of data to the period of record and used modified flow regimes based work from the AMU's Objective <span class="hlt">Lightning</span> Probability Forecast Tool, Phase II. The AMU made changes so the 5- and 10-NM radius range rings are consistent with the aviation forecast requirements at NWS MLB, while the 20- and 30-NM radius range rings at the SLF assist the Spaceflight Meteorology Group in making forecasts for weather Flight Rule violations during Shuttle landings. The AMU also updated the graphical user interface with the new data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110008654','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110008654"><span>The <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM): Status and Recent Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William; Khan, Maudood; Peterson, Harold</p> <p>2011-01-01</p> <p>Improvements to the NASA Marshall Space Flight Center <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) are discussed. Recent results from an August 2006 run of the Community Multiscale Air Quality (CMAQ) modeling system that employs LNOM <span class="hlt">lightning</span> NOx (= NO + NO2) estimates are provided. The LNOM analyzes <span class="hlt">Lightning</span> Mapping Array (LMA) data to estimate the raw (i.e., unmixed and otherwise environmentally unmodified) vertical profile of <span class="hlt">lightning</span> NOx. The latest LNOM estimates of (a) <span class="hlt">lightning</span> channel length distributions, (b) <span class="hlt">lightning</span> 1-m segment altitude distributions, and (c) the vertical profile of NOx are presented. The impact of including LNOM-estimates of <span class="hlt">lightning</span> NOx on CMAQ output is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=steel&pg=3&id=EJ1143063','ERIC'); return false;" href="https://eric.ed.gov/?q=steel&pg=3&id=EJ1143063"><span>A Comparative Study of Two Types of <span class="hlt">Ball-on-Ball</span> Collision</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>White, Colin</p> <p>2017-01-01</p> <p>This paper describes three methods of measuring the coefficient of restitution (CoR) for two different types of <span class="hlt">ball-on-ball</span> collision. The first collision type (for which two different CoR measurement procedures are described) is a static, hanging steel <span class="hlt">ball</span> forming part of a Newton's cradle arrangement, which is then hit by its adjacent…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRD..11718213Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRD..11718213Y"><span>Aerosol indirect effect on tropospheric ozone via <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yuan, Tianle; Remer, Lorraine A.; Bian, Huisheng; Ziemke, Jerald R.; Albrecht, Rachel; Pickering, Kenneth E.; Oreopoulos, Lazaros; Goodman, Steven J.; Yu, Hongbin; Allen, Dale J.</p> <p>2012-09-01</p> <p>Tropospheric ozone (O3) is a pollutant and major greenhouse gas and its radiative forcing is still uncertain. Inadequate understanding of processes related to O3 production, in particular those natural ones such as <span class="hlt">lightning</span>, contributes to this uncertainty. Here we demonstrate a new effect of aerosol particles on O3production by affecting <span class="hlt">lightning</span> activity and <span class="hlt">lightning</span>-generated NOx (LNOx). We find that <span class="hlt">lightning</span> flash rate increases at a remarkable rate of 30 times or more per unit of aerosol optical depth. We provide observational evidence that indicates the observed increase in <span class="hlt">lightning</span> activity is caused by the influx of aerosols from a volcano. Satellite data analyses show O3is increased as a result of aerosol-induced increase in <span class="hlt">lightning</span> and LNOx, which is supported by modle simulations with prescribed <span class="hlt">lightning</span> change. O3production increase from this aerosol-<span class="hlt">lightning</span>-ozone link is concentrated in the upper troposphere, where O3 is most efficient as a greenhouse gas. In the face of anthropogenic aerosol increase our findings suggest that <span class="hlt">lightning</span> activity, LNOx and O3, especially in the upper troposphere, have all increased substantially since preindustrial time due to the proposed aerosol-<span class="hlt">lightning</span>-ozone link, which implies a stronger O3 historical radiative forcing. Aerosol forcing therefore has a warming component via its effect on O3 production and this component has mostly been ignored in previous studies of climate forcing related to O3and aerosols. Sensitivity simulations suggest that 4-8% increase of column tropospheric ozone, mainly in the tropics, is expected if aerosol-lighting-ozone link is parameterized, depending on the background emission scenario. We note, however, substantial uncertainties remain on the exact magnitude of aerosol effect on tropospheric O3 via <span class="hlt">lightning</span>. The challenges for obtaining a quantitative global estimate of this effect are also discussed. Our results have significant implications for understanding past and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20030061356&hterms=bateman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dbateman','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20030061356&hterms=bateman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dbateman"><span>A Total <span class="hlt">Lightning</span> Climatology for the Tennessee Valley Region</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>McCaul, E. W.; Goodman, S. J.; Buechler, D. E.; Blakeslee, R.; Christian, H.; Boccippio, D.; Koshak, W.; Bailey, J.; Hallm, J.; Bateman, M.</p> <p>2003-01-01</p> <p>Total flash counts derived from the North Alabama <span class="hlt">Lightning</span> Mapping Array are being processed for 2002 to form a climatology of total <span class="hlt">lightning</span> for the Tennessee Valley region. The data from this active and interesting period will be compared to data fiom the National <span class="hlt">Lightning</span> Detection Network, space-based <span class="hlt">lightning</span> sensors, and weather radars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMAE11A..01G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMAE11A..01G"><span>The GOES-R Geostationary <span class="hlt">Lightning</span> Mapper (GLM)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Goodman, S. J.; Blakeslee, R. J.; Koshak, W. J.; Mach, D. M.; Bailey, J. C.; Buechler, D. E.; Carey, L. D.; Schultz, C. J.; Bateman, M. G.; McCaul, E., Jr.; Stano, G. T.</p> <p>2012-12-01</p> <p>The Geostationary Operational Environmental Satellite (GOES-R) series provides the continuity for the existing GOES system currently operating over the Western Hemisphere. New and improved instrument technology will support expanded detection of environmental phenomena, resulting in more timely and accurate forecasts and warnings. Advancements over current GOES include a new capability for total <span class="hlt">lightning</span> detection (cloud and cloud-to-ground flashes) from the Geostationary <span class="hlt">Lightning</span> Mapper (GLM), and improved temporal, spatial, and spectral resolution for the next generation Advanced Baseline Imager (ABI). The GLM will map total <span class="hlt">lightning</span> activity (in-cloud and cloud-to-ground <span class="hlt">lightning</span> flashes) continuously day and night with near-uniform spatial resolution of 8 km with a product refresh rate of less than 20 sec over the Americas and adjacent oceanic regions. This will aid in forecasting severe storms and tornado activity, and convective weather impacts on aviation safety and efficiency among a number of potential applications. In parallel with the instrument development, an Algorithm Working Group (AWG) <span class="hlt">Lightning</span> Detection Science and Applications Team developed the Level 2 (stroke and flash) algorithms from the Level 1 <span class="hlt">lightning</span> event (pixel level) data. Proxy data sets used to develop the GLM operational algorithms as well as cal/val performance monitoring tools were derived from the NASA <span class="hlt">Lightning</span> Imaging Sensor (LIS) and Optical Transient Detector (OTD) instruments in low earth orbit, and from ground-based <span class="hlt">lightning</span> networks and intensive pre-launch field campaigns. GLM will produce the same or similar <span class="hlt">lightning</span> flash attributes provided by the LIS and OTD, and thus extends their combined climatology over the western hemisphere into the coming decades. Science and application development along with pre-operational product demonstrations and evaluations at NWS forecast offices and NOAA testbeds will prepare the forecasters to use GLM as soon as possible after</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170011702','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170011702"><span><span class="hlt">Lightning</span>-Related Indicators for National Climate Assessment (NCA) Studies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, W.</p> <p>2017-01-01</p> <p>Changes in climate can affect the characteristics of <span class="hlt">lightning</span> (e.g., number of flashes that occur in a region, return stroke current and multiplicity, polarity of charge deposited to ground, and the <span class="hlt">lightning</span> cloud-top optical energy emission). The NASA/MSFC <span class="hlt">Lightning</span> Analysis Tool (LAT) monitors these and other quantities in support of the National Climate Assessment (NCA) program. Changes in <span class="hlt">lightning</span> characteristics lead to changes in <span class="hlt">lightning</span>-caused impacts to humans (e.g., fatalities, injuries, crop/property damage, wildfires, airport delays, changes in air quality).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRD..122.8173H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRD..122.8173H"><span>Do cosmic ray air showers initiate <span class="hlt">lightning</span>?: A statistical analysis of cosmic ray air showers and <span class="hlt">lightning</span> mapping array data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hare, B. M.; Dwyer, J. R.; Winner, L. H.; Uman, M. A.; Jordan, D. M.; Kotovsky, D. A.; Caicedo, J. A.; Wilkes, R. A.; Carvalho, F. L.; Pilkey, J. T.; Ngin, T. K.; Gamerota, W. R.; Rassoul, H. K.</p> <p>2017-08-01</p> <p>It has been argued in the technical literature, and widely reported in the popular press, that cosmic ray air showers (CRASs) can initiate <span class="hlt">lightning</span> via a mechanism known as relativistic runaway electron avalanche (RREA), where large numbers of high-energy and low-energy electrons can, somehow, cause the local atmosphere in a thundercloud to transition to a conducting state. In response to this claim, other researchers have published simulations showing that the electron density produced by RREA is far too small to be able to affect the conductivity in the cloud sufficiently to initiate <span class="hlt">lightning</span>. In this paper, we compare 74 days of cosmic ray air shower data collected in north central Florida during 2013-2015, the recorded CRASs having primary energies on the order of 1016 eV to 1018 eV and zenith angles less than 38°, with <span class="hlt">Lightning</span> Mapping Array (LMA) data, and we show that there is no evidence that the detected cosmic ray air showers initiated <span class="hlt">lightning</span>. Furthermore, we show that the average probability of any of our detected cosmic ray air showers to initiate a <span class="hlt">lightning</span> flash can be no more than 5%. If all <span class="hlt">lightning</span> flashes were initiated by cosmic ray air showers, then about 1.6% of detected CRASs would initiate <span class="hlt">lightning</span>; therefore, we do not have enough data to exclude the possibility that <span class="hlt">lightning</span> flashes could be initiated by cosmic ray air showers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810029852&hterms=Grounded+theory&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DGrounded%2Btheory','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810029852&hterms=Grounded+theory&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DGrounded%2Btheory"><span><span class="hlt">Lightning</span> protection design external tank /Space Shuttle/</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Anderson, A.; Mumme, E.</p> <p>1979-01-01</p> <p>The possibility of <span class="hlt">lightning</span> striking the Space Shuttle during liftoff is considered and the <span class="hlt">lightning</span> protection system designed by the Martin Marietta Corporation for the external tank (ET) portion of the Shuttle is discussed. The protection system is based on diverting and/or directing a <span class="hlt">lightning</span> strike to an area of the spacecraft which can sustain the strike. The ET <span class="hlt">lightning</span> protection theory and some test analyses of the system's design are reviewed including studies of conductivity and thermal/stress properties in materials, belly band feasibility, and burn-through plug grounding and puncture voltage. The ET <span class="hlt">lightning</span> protection system design is shown to be comprised of the following: (1) a <span class="hlt">lightning</span> rod on the forward most point of the ET, (2) a continually grounded, one inch wide conductive strip applied circumferentially at station 371 (belly band), (3) a three inch wide conductive belly band applied over the TPS (i.e. the insulating surface of the ET) and grounded to a structure with eight conductive plugs at station 536, and (4) a two inch thick TPS between the belly bands which are located over the weld lands.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20070037461&hterms=Wrf&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DWrf','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20070037461&hterms=Wrf&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DWrf"><span>High-Resolution WRF Forecasts of <span class="hlt">Lightning</span> Threat</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodman, S. J.; McCaul, E. W., Jr.; LaCasse, K.</p> <p>2007-01-01</p> <p>Tropical Rainfall Measuring Mission (TRMM)<span class="hlt">lightning</span> and precipitation observations have confirmed the existence of a robust relationship between <span class="hlt">lightning</span> flash rates and the amount of large precipitating ice hydrometeors in storms. This relationship is exploited, in conjunction with the capabilities of the Weather Research and Forecast (WRF) model, to forecast the threat of <span class="hlt">lightning</span> from convective storms using the output fields from the model forecasts. The simulated vertical flux of graupel at -15C is used in this study as a proxy for charge separation processes and their associated <span class="hlt">lightning</span> risk. Initial experiments using 6-h simulations are conducted for a number of case studies for which three-dimensional <span class="hlt">lightning</span> validation data from the North Alabama <span class="hlt">Lightning</span> Mapping Array are available. The WRF has been initialized on a 2 km grid using Eta boundary conditions, Doppler radar radial velocity and reflectivity fields, and METAR and ACARS data. An array of subjective and objective statistical metrics is employed to document the utility of the WRF forecasts. The simulation results are also compared to other more traditional means of forecasting convective storms, such as those based on inspection of the convective available potential energy field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29362499','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29362499"><span>First experimental observations on melting and chemical modification of volcanic ash during <span class="hlt">lightning</span> interaction.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mueller, S P; Helo, C; Keller, F; Taddeucci, J; Castro, J M</p> <p>2018-01-23</p> <p>Electrification in volcanic ash plumes often leads to syn-eruptive <span class="hlt">lightning</span> discharges. High temperatures in and around <span class="hlt">lightning</span> plasma channels have the potential to chemically alter, re-melt, and possibly volatilize ash fragments in the eruption cloud. In this study, we experimentally simulate temperature conditions of volcanic <span class="hlt">lightning</span> in the <span class="hlt">laboratory</span>, and systematically investigate the effects of rapid melting on the morphology and chemical composition of ash. Samples of different size and composition are ejected towards an artificially generated electrical arc. Post-experiment ash morphologies include fully melted spheres, partially melted particles, agglomerates, and vesiculated particles. High-speed imaging reveals various processes occurring during the short <span class="hlt">lightning</span>-ash interactions, such as particle melting and rounding, foaming, and explosive particle fragmentation. Chemical analyses of the flash-melted particles reveal considerable bulk loss of Cl, S, P and Na through thermal vaporization. Element distribution patterns suggest convection as a key process of element transport from the interior of the melt droplet to rim where volatiles are lost. Modeling the degree of sodium loss delivers maximum melt temperatures between 3290 and 3490 K. Our results imply that natural lighting strikes may be an important agent of syn-eruptive morphological and chemical processing of volcanic ash.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850009173','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850009173"><span>Mathematical physics approaches to <span class="hlt">lightning</span> discharge problems</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kyrala, A.</p> <p>1985-01-01</p> <p>Mathematical physics arguments useful for <span class="hlt">lightning</span> discharge and generation problems are pursued. A soliton Ansatz for the <span class="hlt">lightning</span> stroke is treated including a charge generation term which is the ultimate source for the phenomena. Equations are established for a partially ionized plasma inding the effects of pressure, magnetic field, electric field, gravitation, viscosity, and temperature. From these equations is then derived the non-stationary generalized Ohm's Law essential for describing field/current density relationships in the horizon channel of the <span class="hlt">lightning</span> stroke. The discharge initiation problem is discussed. It is argued that the ionization rate drives both the convective current and electric displacement current to increase exponentially. The statistical distributions of charge in the thundercloud preceding a <span class="hlt">lightning</span> dischage are considered. The stability of the pre-<span class="hlt">lightning</span> charge distributions and the use of Boltzmann relaxational equations to determine them are discussed along with a covered impedance path provided by the aircraft.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990108685&hterms=self+harm&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dself%2Bharm','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990108685&hterms=self+harm&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dself%2Bharm"><span><span class="hlt">Lightning</span> Launch Commit Criteria for America's Space Program</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Roeder, W. P.; Sardonia, J. E.; Jacobs, S. C.; Hinson, M. S.; Harms, D. E.; Madura, J. T.; DeSordi, S. P.</p> <p>1999-01-01</p> <p>The danger of natural and triggered <span class="hlt">lightning</span> significantly impacts space launch operations supported by the USAF. The <span class="hlt">lightning</span> Launch Commit Criteria (LCC) are used by the USAF to avoid these <span class="hlt">lightning</span> threats to space launches. This paper presents a brief overview of the LCC.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130011295','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130011295"><span>Objective <span class="hlt">Lightning</span> Forecasting at Kennedy Space Center/Cape Canaveral Air Force Station using Cloud-to-Ground <span class="hlt">Lightning</span> Surveillance System Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lambert, Winifred; Wheeler, Mark</p> <p>2004-01-01</p> <p>The 45th Weather Squadron (45 WS) forecasters at Cape Canaveral Air Force Station (CCAFS) in Florida include a probability of thunderstorm occurrence in their daily morning briefings. This information is used by personnel involved in determining the possibility of violating Launch Commit Criteria, evaluating Flight Rules for the Space Shuttle, and daily planning for ground operation activities on Kennedy Space Center (KSC)/CCAFS. Much of the current <span class="hlt">lightning</span> probability forecast is based on a subjective analysis of model and observational data. The forecasters requested that a <span class="hlt">lightning</span> probability forecast tool based on statistical analysis of historical warm-season (May - September) data be developed in order to increase the objectivity of the daily thunderstorm probability forecast. The tool is a set of statistical <span class="hlt">lightning</span> forecast equations that provide a <span class="hlt">lightning</span> occurrence probability for the day by 1100 UTC (0700 EDT) during the warm season. This study used 15 years (1989-2003) of warm season data to develop the objective forecast equations. The local CCAFS 1000 UTC sounding was used to calculate stability parameters for equation predictors. The Cloud-to-Ground <span class="hlt">Lightning</span> Surveillance System (CGLSS) data were used to determine <span class="hlt">lightning</span> occurrence for each day. The CGLSS data have been found to be more reliable indicators of <span class="hlt">lightning</span> in the area than surface observations through local informal analyses. This work was based on the results from two earlier research projects. Everitt (1999) used surface observations and rawinsonde data to develop logistic regression equations that forecast the daily thunderstorm probability at CCAFS. The Everitt (1999) equations showed an improvement in skill over the Neumann-Pfeffer thunderstorm index (Neumann 1971), which uses multiple linear regression, and also persistence and climatology forecasts. Lericos et al. (2002) developed <span class="hlt">lightning</span> distributions over the Florida peninsula based on specific flow regimes. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110014415','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110014415"><span>Stemless <span class="hlt">ball</span> valve</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burgess, Kevin (Inventor); Yakos, David (Inventor); Walthall, Bryan (Inventor)</p> <p>2011-01-01</p> <p>A stemless <span class="hlt">ball</span> valve comprising two flanges and a <span class="hlt">ball</span> with a channel, two axis pins and two travel pins. One end of each axis and travel pin is fixedly attached to the <span class="hlt">ball</span>, and the other end of each axis pin is lodged into a notch in the first or second flange such that the axis pin is allowed to rotate in the notch. The guide sleeve comprises two channels, and one end of each travel pin is situated within one of the two channels in the guide sleeve. An outer magnetic cartridge causes the inner magnetic cartridge and guide sleeve to rotate, and when the guide sleeve rotates, the travel pins move up and down within the channels in the guide sleeve. The movement of the travel pins within the channels in the guide sleeve causes the <span class="hlt">ball</span> to rotate, thereby opening and closing the <span class="hlt">ball</span> valve.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27116922','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27116922"><span><span class="hlt">Lightning</span> Strike in Pregnancy With Fetal Injury.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Galster, Kellen; Hodnick, Ryan; Berkeley, Ross P</p> <p>2016-06-01</p> <p>Injuries from <span class="hlt">lightning</span> strikes are an infrequent occurrence, and are only rarely noted to involve pregnant victims. Only 13 cases of <span class="hlt">lightning</span> strike in pregnancy have been previously described in the medical literature, along with 7 additional cases discovered within news media reports. This case report presents a novel case of <span class="hlt">lightning</span>-associated injury in a patient in the third trimester of pregnancy, resulting in fetal ischemic brain injury and long-term morbidity, and reviews the mechanics of <span class="hlt">lightning</span> strikes along with common injury patterns of which emergency providers should be aware. Copyright © 2016 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140007322','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140007322"><span>Correlation of DIAL Ozone Observations with <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Peterson, Harold; Kuang, Shi; Koshak, William; Newchurch, Michael</p> <p>2014-01-01</p> <p>The purpose of this project is to see whether ozone maxima measured by the DIfferential Absorption Lidar (DIAL) instrument in Huntsville, AL may be traced back to <span class="hlt">lightning</span> events occurring 24-48 hours beforehand. The methodology is to start with lidar measurements of ozone from DIAL. The HYbrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model is then used to determine the origin of these ozone maxima 24-48 hours prior. Data from the National <span class="hlt">Lightning</span> Detection Network (NLDN) are used to examine the presence/absence of <span class="hlt">lightning</span> along the trajectory. This type of analysis suggests that <span class="hlt">lightning</span>-produced NOx may be responsible for some of the ozone maxima over Huntsville.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870003628&hterms=thunder+lightning&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dthunder%2Blightning','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870003628&hterms=thunder+lightning&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dthunder%2Blightning"><span>Optical characteristics of <span class="hlt">lightning</span> and thunderstorm currents</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Krider, E. P.; Blakeslee, R. J.</p> <p>1985-01-01</p> <p>Researchers determined that <span class="hlt">lightning</span> can be used to determine the diurnal variations of thunderstorms, i.e., storms that produce audible thunder, and that these variations are also in good agreement with diurnal variations in rainfall and convective activity. Measurements of the Maxwell current density, J sub m, under active thunderstorms show that this physical quantity is quasi-steady between <span class="hlt">lightning</span> discharges and that <span class="hlt">lightning</span> does not produce large changes in J sub m. Maps of J sub m show contours of iso-current density that are consistent with the locations of radar echos and the locations of where <span class="hlt">lightning</span> has altered the cloud charge distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/41133','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/41133"><span>Brown carbon in tar <span class="hlt">balls</span> from smoldering biomass combustion</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>R. K. Chakrabarty; H. Moosmuller; L.-W. A. Chen; K. Lewis; W. P. Arnott; C. Mazzoleni; M. K. Dubey; C. E. Wold; W. M. Hao; S. M. Kreidenweis</p> <p>2010-01-01</p> <p>We report the direct observation of <span class="hlt">laboratory</span> production of spherical, carbonaceous particles - "tar <span class="hlt">balls</span>" - from smoldering combustion of two commonly occurring dry mid-latitude fuels. Real-time measurements of spectrally varying absorption Angstrom coefficients (AAC) indicate that a class of light absorbing organic carbon (OC) with wavelength dependent...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800015163','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800015163"><span>Quartz <span class="hlt">ball</span> valve</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goetz, C.; Ingle, W. M. (Inventor)</p> <p>1980-01-01</p> <p>A <span class="hlt">ball</span> valve particularly suited for use in the handling of highly corrosive fluids is described. It is characterized by a valve housing formed of communicating segments of quartz tubing, a pair of communicating sockets disposed in coaxial alignment with selected segments of tubing for establishing a pair of inlet ports communicating with a common outlet port, a <span class="hlt">ball</span> formed of quartz material supported for displacement between the sockets and configured to be received alternately thereby, and a valve actuator including a rod attached to the <span class="hlt">ball</span> for selectively displacing the <span class="hlt">ball</span> relative to each of the sockets for controlling fluid flow through the inlet ports.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19780011095','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19780011095"><span>Wear-resistant <span class="hlt">ball</span> bearings for space applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Boving, H.; Hintermann, H. E.; Hanni, W.; Bondivenne, E.; Boeto, M.; Conde, E.</p> <p>1977-01-01</p> <p><span class="hlt">Ball</span> bearings consisting of steel parts of which the rings are coated with hard, wear resistant, chemical vapor deposited TiC are described. Experiments conducted in ultrahigh vacuum, using cages of various materials with self-lubricating properties, show that such bearings are suitable for space applications. The results of <span class="hlt">laboratory</span> tests on the ESA Meteosat Radiometer Focalizing mechanism, which contains six coated bearings, are summarized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.5953C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.5953C"><span>The Statistic Results of the ISUAL <span class="hlt">Lightning</span> Survey</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chuang, Chia-Wen; Bing-Chih Chen, Alfred; Liu, Tie-Yue; Lin, Shin-Fa; Su, Han-Tzong; Hsu, Rue-Ron</p> <p>2017-04-01</p> <p>The ISUAL (Imager for Sprites and Upper Atmospheric <span class="hlt">Lightning</span>) onboard FORMOSAT-2 is the first science payload dedicated to the study of the <span class="hlt">lightning</span>-induced transient luminous events (TLEs). Transient events, including TLEs and <span class="hlt">lightning</span>, were recorded by the intensified imager, spectrophotometer (SP), and array photometer (AP) simultaneously while their light variation observed by SP exceeds a programmed threshold. Therefore, ISUAL surveys not only TLEs but also <span class="hlt">lightning</span> globally with a good spatial, temporal and spectral resolution. In the past 12 years (2004-2016), approximately 300,000 transient events were registered, and only 42,000 are classified as TLEs. Since the main mission objective is to explore the distribution and characteristics of TLEs, the remaining transient events, mainly <span class="hlt">lightning</span>, can act as a long-term global <span class="hlt">lightning</span> survey. These huge amount of events cannot be processed manually as TLEs do, therefore, a data pipeline is developed to scan <span class="hlt">lightning</span> patterns and to derive their geolocation with an efficient algorithm. The 12-year statistic results including occurrence rate, global distribution, seasonal variation, and the comparison with the LIS/OTD survey are presented in this report.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5503225','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5503225"><span>Individual <span class="hlt">ball</span> possession in soccer</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hoernig, Martin</p> <p>2017-01-01</p> <p>This paper describes models for detecting individual and team <span class="hlt">ball</span> possession in soccer based on position data. The types of <span class="hlt">ball</span> possession are classified as Individual <span class="hlt">Ball</span> Possession (IBC), Individual <span class="hlt">Ball</span> Action (IBA), Individual <span class="hlt">Ball</span> Control (IBC), Team <span class="hlt">Ball</span> Possession (TBP), Team <span class="hlt">Ball</span> Control (TBC) und Team Playmaking (TPM) according to different starting points and endpoints and the type of <span class="hlt">ball</span> control involved. The machine learning approach used is able to determine how long the <span class="hlt">ball</span> spends in the sphere of influence of a player based on the distance between the players and the <span class="hlt">ball</span> together with their direction of motion, speed and the acceleration of the <span class="hlt">ball</span>. The degree of <span class="hlt">ball</span> control exhibited during this phase is classified based on the spatio-temporal configuration of the player controlling the <span class="hlt">ball</span>, the <span class="hlt">ball</span> itself and opposing players using a Bayesian network. The evaluation and application of this approach uses data from 60 matches in the German Bundesliga season of 2013/14, including 69,667 IBA intervals. The identification rate was F = .88 for IBA and F = .83 for IBP, and the classification rate for IBC was κ = .67. Match analysis showed the following mean values per match: TBP 56:04 ± 5:12 min, TPM 50:01 ± 7:05 min and TBC 17:49 ± 8:13 min. There were 836 ± 424 IBC intervals per match and their number was significantly reduced by -5.1% from the 1st to 2nd half. The analysis of <span class="hlt">ball</span> possession at the player level indicates shortest accumulated IBC times for the central forwards (0:49 ± 0:43 min) and the longest for goalkeepers (1:38 ± 0:58 min), central defenders (1:38 ± 1:09 min) and central midfielders (1:27 ± 1:08 min). The results could improve performance analysis in soccer, help to detect match events automatically, and allow discernment of higher value tactical structures, which is based on individual <span class="hlt">ball</span> possession. PMID:28692649</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=deodorant&id=EJ382825','ERIC'); return false;" href="https://eric.ed.gov/?q=deodorant&id=EJ382825"><span>Ban Deodorant <span class="hlt">Ball</span> Mortar.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Carpenter, D. Rae, Jr.; And Others</p> <p>1988-01-01</p> <p>Discusses a demonstration of vertical collision of two <span class="hlt">balls</span>. Shows the theoretical height ratio using mathematical expression and diagrams. Compares it with researchers' experimental results. Expands the two-<span class="hlt">ball</span> collision to multi-<span class="hlt">ball</span> system. (YP)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AtmRe.197...76S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AtmRe.197...76S"><span>Performance assessment of Beijing <span class="hlt">Lightning</span> Network (BLNET) and comparison with other <span class="hlt">lightning</span> location networks across Beijing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Srivastava, Abhay; Tian, Ye; Qie, Xiushu; Wang, Dongfang; Sun, Zhuling; Yuan, Shanfeng; Wang, Yu; Chen, Zhixiong; Xu, Wenjing; Zhang, Hongbo; Jiang, Rubin; Su, Debin</p> <p>2017-11-01</p> <p>The performances of Beijing <span class="hlt">Lightning</span> Network (BLNET) operated in Beijing-Tianjin-Hebei urban cluster area have been evaluated in terms of detection efficiency and relative location accuracy. A self-reference method has been used to show the detection efficiency of BLNET, for which fast antenna waveforms have been manually examined. Based on the fast antenna verification, the average detection efficiency of BLNET is 97.4% for intracloud (IC) flashes, 73.9% for cloud-to-ground (CG) flashes and 93.2% for the total flashes. Result suggests the CG detection of regional dense network is highly precise when the thunderstorm passes over the network; however it changes day to day when the thunderstorms are outside the network. Further, the CG stroke data from three different <span class="hlt">lightning</span> location networks across Beijing are compared. The relative detection efficiency of World Wide <span class="hlt">Lightning</span> Location Network (WWLLN) and Chinese Meteorology Administration - <span class="hlt">Lightning</span> Detection Network (CMA-LDN, also known as ADTD) are approximately 12.4% (16.8%) and 36.5% (49.4%), respectively, comparing with fast antenna (BLNET). The location of BLNET is in middle, while WWLLN and CMA-LDN average locations are southeast and northwest, respectively. Finally, the IC pulses and CG return stroke pulses have been compared with the S-band Doppler radar. This type of study is useful to know the approximate situation in a region and improve the performance of <span class="hlt">lightning</span> location networks in the absence of ground truth. Two <span class="hlt">lightning</span> flashes occurred on tower in the coverage of BLNET show that the horizontal location error was 52.9 m and 250 m, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/976609','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/976609"><span>Global optical <span class="hlt">lightning</span> flash rates determined with the Forte satellite</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Light, T.; Davis, S. M.; Boeck, W. L.</p> <p>2003-01-01</p> <p>Using FORTE photodiode detector (PDD) observations of <span class="hlt">lightning</span>, we have determined the geographic distribution of nighttime flash rate density. We estimate the PDD flash detection efficiency to be 62% for total <span class="hlt">lightning</span> through comparison to <span class="hlt">lightning</span> observations by the TRMM satellite's <span class="hlt">Lightning</span> Imaging Sensor (LIS), using cases in which FORTE and TRMM viewed the same storm. We present here both seasonal and l,ot,al flash rate maps. We examine some characteristics of the optical emissions of <span class="hlt">lightning</span> in both high and low flash rate environments, and find that while <span class="hlt">lightning</span> occurs less frequently over ocean, oceanic <span class="hlt">lightning</span> flashes are somewhat moremore » powerful, on average, than those over land.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20100002101&hterms=climate+facts&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dclimate%2Bfacts','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20100002101&hterms=climate+facts&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dclimate%2Bfacts"><span>Climate Change and Tropical Total <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Albrecht, R.; Petersen, W.; Buechler, D.; Goodman, S.; Blakeslee, R.; Christian, H.</p> <p>2009-01-01</p> <p>While global warming is regarded as a fact by many in the scientific community, its future impact remains a challenge to be determined and measured. The International Panel on Climate Change (IPCC) assessment report (IPCC, 2007) shows inconclusive answers on global rainfall trends and general agreement on a future drier climate with increased global warming. The relationship between temperature, humidity and convection is not linear and is strongly dependent on regional scale features, such as topography and land cover. Furthermore, the relationship between convective <span class="hlt">lightning</span> production (thunderstorms) and temperature is even more complicated, being subjected to the cloud dynamics and microphysics. Total <span class="hlt">lightning</span> (intracloud and cloud-to-ground) monitoring is a relatively new field of observation. Global and tropical total <span class="hlt">lightning</span> began to be more extensively measured by satellites in the mid 90s. In this scope, the <span class="hlt">Lightning</span> Imaging Sensor (LIS) onboard of the Tropical Rainfall Measurement Mission (TRMM) has been operational for over 11 years. Here we address total <span class="hlt">lightning</span> trends observed by LIS from 1998 to 2008 in different temporal (annual and seasonal) and spatial (large and regional) scales. The observed 11-year trends are then associate to different predicted/hypothesized climate change scenarios.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFMAE21A0296W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFMAE21A0296W"><span>A comparison between initial continuous currents of different types of upward <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, D.; Sawada, N.; Takagi, N.</p> <p>2009-12-01</p> <p>We have observed the <span class="hlt">lightning</span> to a wind turbine and its <span class="hlt">lightning</span>-protection tower for four consecutive winter seasons from 2005 to 2009. Our observation items include (1) thunderstorm electrical fields and <span class="hlt">lightning</span>-caused electric field changes at multi sites around the wind turbine, (2) electrical currents at the bottom of the wind turbine and its <span class="hlt">lightning</span> protection tower, (3) normal video and high speed image of <span class="hlt">lightning</span> optical channels. Totally, we have obtained the data for 42 <span class="hlt">lightning</span> that hit either on wind turbine or its <span class="hlt">lightning</span> protection tower or both. Among these 42 <span class="hlt">lightning</span>, 38 are upward <span class="hlt">lightning</span> and 2 are downward <span class="hlt">lightning</span>. We found the upward <span class="hlt">lightning</span> can be sub-classified into two types. Type 1 upward <span class="hlt">lightning</span> are self-triggered from a high structure, while type 2 <span class="hlt">lightning</span> are triggered by a discharge occurred in other places which could be either a cloud discharge or a cloud-to-ground discharge (other-triggered). In this study, we have compared the two types of upward <span class="hlt">lightning</span> in terms of initial continuous current rise time, peak current and charge transferred to the ground. We found that the initial current of self-triggered <span class="hlt">lightning</span> tends to rise significantly faster and to a bigger peak value than the other-triggered <span class="hlt">lightning</span>, although both types of <span class="hlt">lightning</span> transferred similar amount of charge to the ground.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840002593','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840002593"><span>How to protect a wind turbine from <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dodd, C. W.; Mccalla, T., Jr.; Smith, J. G.</p> <p>1983-01-01</p> <p>Techniques for reducing the chances of <span class="hlt">lightning</span> damage to wind turbines are discussed. The methods of providing a ground for a <span class="hlt">lightning</span> strike are discussed. Then details are given on ways to protect electronic systems, generating and power equipment, blades, and mechanical components from direct and nearby <span class="hlt">lightning</span> strikes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24054789','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24054789"><span>"Thunderstruck": penetrating thoracic injury from <span class="hlt">lightning</span> strike.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>van Waes, Oscar J F; van de Woestijne, Pieter C; Halm, Jens A</p> <p>2014-04-01</p> <p><span class="hlt">Lightning</span> strike victims are rarely presented at an emergency department. Burns are often the primary focus. This case report describes the improvised explosive device like-injury to the thorax due to <span class="hlt">lightning</span> strike and its treatment, which has not been described prior in (kerauno)medicine. Penetrating injury due to blast from <span class="hlt">lightning</span> strike is extremely rare. These "shrapnel" injuries should however be ruled out in all patients struck by <span class="hlt">lightning</span>. Copyright © 2013 American College of Emergency Physicians. Published by Mosby, Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMAE13B..02S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE13B..02S"><span>The Interferometric View of <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stock, M.; Lapierre, J. L.</p> <p>2017-12-01</p> <p>Recent advances in off the shelf high-speed digitizers has enabled vast improvements in broadband, digital VHF interferometers. These simple instruments consist of 3 or more VHF antennas distributed in an array which are then digitized at a speed above the Nyquist frequency of the antenna bandwidth (usually 200+ MHz). Broadband interferometers are capable of creating very detailed maps of <span class="hlt">lightning</span>, with time resolution better than 1us, and angular resolution only limited by their baseline lengths. This is combined with high sensitivity, and the ability to locate both continuously emitting and impulsive radiation sources. They are not without their limitations though. Because the baselines are relatively short, the maps are only 2-dimensional (direction to the source), unless many antennas are used only a single VHF radiation source can be located at any instant, and because the antennas are almost always arranged in a planar array they are better suited for observing <span class="hlt">lightning</span> at high elevation angles. Even though imperfect, VHF interferometers provide one of the most detailed views of the behavior of <span class="hlt">lightning</span> flashes inside a cloud. This presentation will present the overall picture of in-cloud <span class="hlt">lightning</span> as seen by VHF interferometers. Most flashes can be split into 3 general phases of activity. Phase 1 is the initiation phase, covering all activity until the negative leader completes its vertical extension, and includes both <span class="hlt">lightning</span> initiation and initial breakdown pulses. Phase 2 is the active phase and includes all activity during the horizontal extension of the negative leader. During Phase 2, any K-processes which occur tend to be short in duration and extent. Phase 3 is the final phase, and includes all activity after the negative leader stops propagating. During Phase 3, the conductivity of the <span class="hlt">lightning</span> channels starts to decline, and extensive K-processes are seen which traverse the entire channel structure, this is also the period in which regular</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMAE23B0319R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMAE23B0319R"><span>The Colorado <span class="hlt">Lightning</span> Mapping Array</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rison, W.; Krehbiel, P. R.; Thomas, R. J.; Rodeheffer, D.; Fuchs, B.</p> <p>2012-12-01</p> <p>A fifteen station <span class="hlt">Lightning</span> Mapping Array (LMA) was installed in northern Colorado in the spring of 2012. While the driving force for the array was to produce 3-dimensional <span class="hlt">lightning</span> data to support the Deep Convective Clouds and Chemistry (DC3) Experiment (Barth, this conference), data from the array are being used for several other projects. These include: electrification studies in conjunction with the CSU CHILL radar (Lang et al, this conference); observations of the parent <span class="hlt">lightning</span> discharges of sprites (Lyons et al, this conference); trying to detect upward discharges triggered by wind turbines, characterizing conditions in which aircraft flying through clouds produce discharges which can be detected by the LMA, and other opportunities, such as observations of <span class="hlt">lightning</span> in pyrocumulus clouds produced by the High Park Fire west of Fort Collins, CO. All the COLMA stations are solar-powered, and use broadband cellular modems for data communications. This makes the stations completely self-contained and autonomous, allowing a station to be installed anywhere a cellular signal is available. Because most of the stations were installed well away from anthropogenic noise sources, the COLMA is very sensitive. This is evidenced by the numerous plane tracks detected in its the vicinity. The diameter, D, of the COLMA is about 100 km, significantly larger than other LMAs. Because the error in the radial distance r is proportional to (r/D)2, and the error in the altitude z is proportional to (z/D)2, the larger array diameter greatly expands the usable range of the COLMA. The COLMA is able to detect and characterize lighting flashes to a distance of about 350 km from the array center. In addition to a web-based display (<span class="hlt">lightning</span>.nmt.edu/colma), geo-referenced images are produced and updated at one-minute intervals. These geo-referenced images can be used to overlay the real-time <span class="hlt">lightning</span> data on Google Earth and other mapping software. These displays were used by the DC3</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19810016745','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19810016745"><span>Noise and interference study for satellite <span class="hlt">lightning</span> sensor</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Herman, J. R.</p> <p>1981-01-01</p> <p>The use of radio frequency techniques for the detection and monitoring of terrestrial thunderstorms from space are discussed. Three major points are assessed: (1) <span class="hlt">lightning</span> and noise source characteristics; (2) propagation effects imposed by the atmosphere and ionosphere; and (3) the electromagnetic environment in near space within which <span class="hlt">lightning</span> RF signatures must be detected. A composite frequency spectrum of the peak of amplitude from <span class="hlt">lightning</span> flashes is developed. Propagation effects (ionospheric cutoff, refraction, absorption, dispersion and scintillation) are considered to modify the <span class="hlt">lightning</span> spectrum to the geosynchronous case. It is suggested that in comparing the modified spectrum with interfering noise source spectra RF <span class="hlt">lightning</span> pulses on frequencies up to a few GHz are detectable above the natural noise environment in near space.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005EOSTr..86..398S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005EOSTr..86..398S"><span>Katrina and Rita were lit up with <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shao, X.-M.; Harlin, J.; Stock, M.; Stanley, M.; Regan, A.; Wiens, K.; Hamlin, T.; Pongratz, M.; Suszcynsky, D.; Light, T.</p> <p></p> <p>Hurricanes generally produce very little <span class="hlt">lightning</span> activity compared to other noncyclonic storms, and <span class="hlt">lightning</span> is especially sparse in the eye wall and inner regions within tens of kilometers surrounding the eye [Molinari et al., 1994, 1999]. (The eye wall is the wall of clouds that encircles the eye of the hurricane.) <span class="hlt">Lightning</span> can sometimes be detected in the outer, spiral rainbands, but the <span class="hlt">lightning</span> occurrence rate varies significantly from hurricane to hurricane as well as within an individual hurricane's lifetime.Hurricanes Katrina and Rita hit the U.S. Gulf coasts of Louisiana, Mississippi, and Texas, and their distinctions were not just limited to their tremendous intensity and damage caused. They also differed from typical hurricanes in their <span class="hlt">lightning</span> production rate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770011155','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770011155"><span>Status of research into <span class="hlt">lightning</span> effects on aircraft</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Plumer, J. A.</p> <p>1976-01-01</p> <p>Developments in aircraft <span class="hlt">lightning</span> protection since 1938 are reviewed. Potential <span class="hlt">lightning</span> problems resulting from present trends toward the use of electronic controls and composite structures are discussed, along with presently available <span class="hlt">lightning</span> test procedures for problem assessment. The validity of some procedures is being questioned because of pessimistic results and design implications. An in-flight measurement program is needed to provide statistics on <span class="hlt">lightning</span> severity at flight altitudes and to enable more realistic tests, and operators are urged to supply researchers with more details on electronic components damaged by <span class="hlt">lightning</span> strikes. A need for review of certain aspects of fuel system vulnerability is indicated by several recent accidents, and specific areas for examination are identified. New educational materials and standardization activities are also noted.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015811','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015811"><span>The NASA <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM): Recent Updates and Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William; Peterson, Harold; Biazar, Arastoo; Khan, Maudood; Wang, Lihua; Park, Yee-Hun</p> <p>2011-01-01</p> <p>Improvements to the NASA Marshall Space Flight Center <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) and its application to the Community Multiscale Air Quality (CMAQ) modeling system are presented. The LNOM analyzes <span class="hlt">Lightning</span> Mapping Array (LMA) and National <span class="hlt">Lightning</span> Detection Network(tm) (NLDN) data to estimate the raw (i.e., unmixed and otherwise environmentally unmodified) vertical profile of <span class="hlt">lightning</span> NOx (= NO + NO2). <span class="hlt">Lightning</span> channel length distributions and <span class="hlt">lightning</span> 10-m segment altitude distributions are also provided. In addition to NOx production from <span class="hlt">lightning</span> return strokes, the LNOM now includes non-return stroke <span class="hlt">lightning</span> NOx production due to: hot core stepped and dart leaders, stepped leader corona sheath, K-changes, continuing currents, and M-components. The impact of including LNOM-estimates of <span class="hlt">lightning</span> NOx for an August 2006 run of CMAQ is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMAE31B0435H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMAE31B0435H"><span>Performance Study of Earth Networks Total <span class="hlt">Lightning</span> Network using Rocket-Triggered <span class="hlt">Lightning</span> Data in 2014</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Heckman, S.</p> <p>2015-12-01</p> <p>Modern <span class="hlt">lightning</span> locating systems (LLS) provide real-time monitoring and early warning of lightningactivities. In addition, LLS provide valuable data for statistical analysis in <span class="hlt">lightning</span> research. It isimportant to know the performance of such LLS. In the present study, the performance of the EarthNetworks Total <span class="hlt">Lightning</span> Network (ENTLN) is studied using rocket-triggered <span class="hlt">lightning</span> data acquired atthe International Center for <span class="hlt">Lightning</span> Research and Testing (ICLRT), Camp Blanding, Florida.In the present study, 18 flashes triggered at ICLRT in 2014 were analyzed and they comprise of 78negative cloud-to-ground return strokes. The geometric mean, median, minimum, and maximum for thepeak currents of the 78 return strokes are 13.4 kA, 13.6 kA, 3.7 kA, and 38.4 kA, respectively. The peakcurrents represent typical subsequent return strokes in natural cloud-to-ground <span class="hlt">lightning</span>.Earth Networks has developed a new data processor to improve the performance of their network. Inthis study, results are presented for the ENTLN data using the old processor (originally reported in 2014)and the ENTLN data simulated using the new processor. The flash detection efficiency, stroke detectionefficiency, percentage of misclassification, median location error, median peak current estimation error,and median absolute peak current estimation error for the originally reported data from old processorare 100%, 94%, 49%, 271 m, 5%, and 13%, respectively, and those for the simulated data using the newprocessor are 100%, 99%, 9%, 280 m, 11%, and 15%, respectively. The use of new processor resulted inhigher stroke detection efficiency and lower percentage of misclassification. It is worth noting that theslight differences in median location error, median peak current estimation error, and median absolutepeak current estimation error for the two processors are due to the fact that the new processordetected more number of return strokes than the old processor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20070038367','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20070038367"><span>Diurnal <span class="hlt">Lightning</span> Distributions as Observed by the Optical Transient Detector (OTD) and the <span class="hlt">Lightning</span> Imaging Sensor (LIS)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bailey, Jeff C.; Blakeslee, Richard J.; Buechler, Dennis E.; Christian, Hugh J.</p> <p>2007-01-01</p> <p>Data obtained from the Optical Transient Detector (April 1995 to March 2000) and the <span class="hlt">Lightning</span> Imaging Sensor (December 1997 to December 2005) satellites (70 and 35 inclination low earth orbits, respectively) are used to statistically determine the number of flashes in the annual and seasonal diurnal cycle as a function of local and universal time. The data are further subdivided by season, land versus ocean, northern versus southern hemisphere, and other spatial (e.g., continents) and temporal (e.g., time of peak diurnal amplitude) categories. The data include corrections for detection efficiency and instrument view time. Continental results display strong diurnal variation, with a <span class="hlt">lightning</span> peak in the late afternoon and a minimum in late morning. In regions of the world dominated by large mesoscale convective systems the peak in the diurnal curve shifts toward late evening or early morning hours. The maximum diurnal flash rate occurs in June-August, corresponding to the Northern Hemisphere summer, while the minimum occurs in December-February. Summer <span class="hlt">lightning</span> dominates over winter activity and springtime <span class="hlt">lightning</span> dominates over autumn activity at most continental locations. This latter behavior occurs especially strongly over the Amazon region in South America in September-November. Oceanic <span class="hlt">lightning</span> activity in winter and autumn tends to exceed that in summer and spring. Global <span class="hlt">lightning</span> is well correlated in phase but not in amplitude with the Carnegie curve. The diurnal flash rate varies about 4-35 percent about the mean, while the Carnegie curve varies around 4-15 percent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080002889&hterms=nature&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dnature','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080002889&hterms=nature&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dnature"><span><span class="hlt">Lightning</span>: Nature's Probe of Severe Weather for Research and Operations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Blakeslee, R.J.</p> <p>2007-01-01</p> <p><span class="hlt">Lightning</span>, the energetic and broadband electrical discharge produced by thunderstorms, provides a natural remote sensing signal for the study of severe storms and related phenomena on global, regional and local scales. Using this strong signal- one of nature's own probes of severe weather -<span class="hlt">lightning</span> measurements prove to be straightforward and take advantage of a variety of measurement techniques that have advanced considerably in recent years. We briefly review some of the leading <span class="hlt">lightning</span> detection systems including satellite-based optical detectors such as the <span class="hlt">Lightning</span> Imaging Sensor, and ground-based radio frequency systems such as Vaisala's National <span class="hlt">Lightning</span> Detection Network (NLDN), long range <span class="hlt">lightning</span> detection systems, and the <span class="hlt">Lightning</span> Mapping Array (LMA) networks. In addition, we examine some of the exciting new research results and operational capabilities (e.g., shortened tornado warning lead times) derived from these observations. Finally we look forward to the next measurement advance - <span class="hlt">lightning</span> observations from geostationary orbit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140006433','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140006433"><span>Correlation of DIAL Ozone Observations with <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Peterson, Harold; Kuang, Shi; Koshak, William; Newchurch, Michael</p> <p>2013-01-01</p> <p>The purpose of this project is to see whether ozone maxima measured by the DIfferential Absorption Lidar (DIAL) instrument in Huntsville, AL may be traced back to <span class="hlt">lightning</span> events occurring 24- 48 hours beforehand. The methodology is to start with lidar measurements of ozone from DIAL as well as ozonesonde measurements. The HYbrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model is then used to determine the origin of these ozone maxima 24-48 hours prior. Data from the National <span class="hlt">Lightning</span> Detection Network (NLDN) are used to examine the presence/absence of <span class="hlt">lightning</span> along the trajectory. This type of analysis suggests that <span class="hlt">lightning</span>-produced NOx may be responsible for some of the ozone maxima over Huntsville.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/987257','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/987257"><span>X-ray Emission from Thunderstorms and <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Dwyer, Joseph</p> <p>2009-07-08</p> <p>How <span class="hlt">lightning</span> is initiated in the relatively low electric fields inside thunderclouds and how it can then propagate for tens of kilometers through virgin air are two of the great unsolved problems in the atmospheric sciences.  Until very recently it was believed that <span class="hlt">lightning</span> was entirely a conventional discharge, involving only low-energy (a few eV) electrons.  This picture changed completely a few years ago with the discovery of intense x-ray emission from both natural cloud-to-ground <span class="hlt">lightning</span> and rocket-triggered <span class="hlt">lightning</span>.  This energetic emission cannot be produced by a conventional discharge, and so the presence of x-rays strongly implies that runaway breakdownmore » plays a role in <span class="hlt">lightning</span> processes.  During runaway breakdown, electrons are accelerated through air to nearly the speed of light by strong electric fields.  These runaway electrons then emit bremsstrahlung x-rays and gamma-rays during collisions with air.  Indeed, the x-ray and gamma-ray emission produced by runaway breakdown near the tops of thunderstorms is bright enough to be seen from outer space, 600 km away.  As a result, the physics used for decades to describe thunderstorm electrification and <span class="hlt">lightning</span> discharges is incomplete and needs to be revisited. « less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/sciencecinema/biblio/987257','SCIGOVIMAGE-SCICINEMA'); return false;" href="http://www.osti.gov/sciencecinema/biblio/987257"><span>X-ray Emission from Thunderstorms and <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/sciencecinema/">ScienceCinema</a></p> <p>Dwyer, Joseph [Florida Institute of Technology, Melbourne, Florida, United States</p> <p>2017-12-09</p> <p>How <span class="hlt">lightning</span> is initiated in the relatively low electric fields inside thunderclouds and how it can then propagate for tens of kilometers through virgin air are two of the great unsolved problems in the atmospheric sciences.  Until very recently it was believed that <span class="hlt">lightning</span> was entirely a conventional discharge, involving only low-energy (a few eV) electrons.  This picture changed completely a few years ago with the discovery of intense x-ray emission from both natural cloud-to-ground <span class="hlt">lightning</span> and rocket-triggered <span class="hlt">lightning</span>.  This energetic emission cannot be produced by a conventional discharge, and so the presence of x-rays strongly implies that runaway breakdown plays a role in <span class="hlt">lightning</span> processes.  During runaway breakdown, electrons are accelerated through air to nearly the speed of light by strong electric fields.  These runaway electrons then emit bremsstrahlung x-rays and gamma-rays during collisions with air.  Indeed, the x-ray and gamma-ray emission produced by runaway breakdown near the tops of thunderstorms is bright enough to be seen from outer space, 600 km away.  As a result, the physics used for decades to describe thunderstorm electrification and <span class="hlt">lightning</span> discharges is incomplete and needs to be revisited. </p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24417129','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24417129"><span>[<span class="hlt">Lightning</span>-caused fire, its affecting factors and prediction: a review].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Ji-Li; Bi, Wu; Wang, Xiao-Hong; Wang, Zi-Bo; Li, Di-Fei</p> <p>2013-09-01</p> <p><span class="hlt">Lightning</span>-caused fire is the most important natural fire source. Its induced forest fire brings enormous losses to human beings and ecological environment. Many countries have paid great attention to the prediction of <span class="hlt">lightning</span>-caused fire. From the viewpoint of the main factors affecting the formation of <span class="hlt">lightning</span>-caused fire, this paper emphatically analyzed the effects and action mechanisms of cloud-to-ground <span class="hlt">lightning</span>, fuel, meteorology, and terrain on the formation and development process of <span class="hlt">lightning</span>-caused fire, and, on the basis of this, summarized and reviewed the logistic model, K-function, and other mathematical methods widely used in prediction research of <span class="hlt">lightning</span>-caused fire. The prediction methods and processes of <span class="hlt">lightning</span>-caused fire in America and Canada were also introduced. The insufficiencies and their possible solutions for the present researches as well as the directions of further studies were proposed, aimed to provide necessary theoretical basis and literature reference for the prediction of <span class="hlt">lightning</span>-caused fire in China.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100019595','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100019595"><span>Ceramic Rail-Race <span class="hlt">Ball</span> Bearings</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Balzer, Mark A.; Mungas, Greg S.; Peters, Gregory H.</p> <p>2010-01-01</p> <p>Non-lubricated <span class="hlt">ball</span> bearings featuring rail races have been proposed for use in mechanisms that are required to function in the presence of mineral dust particles in very low-pressure, dry environments with extended life. Like a conventional <span class="hlt">ball</span> bearing, the proposed bearing would include an inner and an outer ring separated by <span class="hlt">balls</span> in rolling contact with the races. However, unlike a conventional <span class="hlt">ball</span> bearing, the <span class="hlt">balls</span> would not roll in semi-circular or gothic arch race grooves in the rings: instead, the races would be shaped to form two or more rails (see figure). During operation, the motion of the <span class="hlt">balls</span> would push dust particles into the spaces between the rails where the particles could not generate rolling resistance for the <span class="hlt">balls</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.A53D0174Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.A53D0174Y"><span>Aerosol indirect effect on tropospheric ozone via <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yuan, T.; Remer, L. A.; Bian, H.; Ziemke, J. R.; Albrecht, R. I.; Pickering, K. E.; Oreopoulos, L.; Goodman, S. J.; Yu, H.; Allen, D. J.</p> <p>2012-12-01</p> <p>Tropospheric ozone (O3) is a pollutant and major greenhouse gas and its radiative forcing is still uncertain. The unresolved difference between modeled and observed natural background O3 concentrations is a key source of the uncertainty. Here we demonstrate remarkable sensitivity of <span class="hlt">lightning</span> activity to aerosol loading with <span class="hlt">lightning</span> activity increasing more than 30 times per unit of aerosol optical depth over our study area. We provide observational evidence that indicates the observed increase in <span class="hlt">lightning</span> activity is caused by the influx of aerosols from a volcano. Satellite data analyses suggest O3 is increased as a result of aerosol-induced increase in <span class="hlt">lightning</span> and <span class="hlt">lightning</span> produced NOx. Model simulations with prescribed <span class="hlt">lightning</span> change corroborate the satellite data analysis. This aerosol-O3 connection is achieved via aerosol increasing <span class="hlt">lightning</span> and thus <span class="hlt">lightning</span> produced nitrogen oxides. This aerosol-<span class="hlt">lightning</span>-ozone link provides a potential physical mechanism that may account for a part of the model-observation difference in background O3 concentration. More importantly, O3 production increase from this link is concentrated in the upper troposphere, where O3 is most efficient as a greenhouse gas. Both of these implications suggest a stronger O3 historical radiative forcing. This introduces a new pathway, through which increasing in aerosols from pre-industrial time to present day enhances tropospheric O3 production. Aerosol forcing thus has a warming component via its effect on O3 production. Sensitivity simulations suggest that 4-8% increase of tropospheric ozone, mainly in the tropics, is expected if aerosol-lighting-ozone link is parameterized, depending on the background emission scenario. We note, however, substantial uncertainties remain on the exact magnitude of aerosol effect on tropospheric O3 via <span class="hlt">lightning</span>. The challenges for obtaining a quantitative global estimate of this effect are also discussed. Our results have significant implications</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15957322','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15957322"><span>Struck-by-<span class="hlt">lightning</span> deaths in the United States.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Adekoya, Nelson; Nolte, Kurt B</p> <p>2005-05-01</p> <p>The objective of the research reported here was to examine the epidemiologic characteristics of struck-by-<span class="hlt">lightning</span> deaths. Using data from both the National Centers for Health Statistics (NCHS) multiple-cause-of-death tapes and the Census of Fatal Occupational Injuries (CFOI), which is maintained by the Bureau of Labor Statistics, the authors calculated numbers and annualized rates of <span class="hlt">lightning</span>-related deaths for the United States. They used resident estimates from population microdata files maintained by the Census Bureau as the denominators. Work-related fatality rates were calculated with denominators derived from the Current Population Survey of employment data. Four illustrative investigative case reports of <span class="hlt">lightning</span>-related deaths were contributed by the New Mexico Office of the Medical Investigator. It was found that a total of 374 struck-by-<span class="hlt">lightning</span> deaths had occurred during 1995-2000 (an average annualized rate of 0.23 deaths per million persons). The majority of deaths (286 deaths, 75 percent) were from the South and the Midwest. The numbers of <span class="hlt">lightning</span> deaths were highest in Florida (49 deaths) and Texas (32 deaths). A total of 129 work-related <span class="hlt">lightning</span> deaths occurred during 1995-2002 (an average annual rate of 0.12 deaths per million workers). Agriculture and construction industries recorded the most fatalities at 44 and 39 deaths, respectively. Fatal occupational injuries resulting from being struck by <span class="hlt">lightning</span> were highest in Florida (21 deaths) and Texas (11 deaths). In the two national surveillance systems examined, incidence rates were higher for males and people 20-44 years of age. In conclusion, three of every four struck-by-<span class="hlt">lightning</span> deaths were from the South and the Midwest, and during 1995-2002, one of every four struck-by-<span class="hlt">lightning</span> deaths was work-related. Although prevention programs could target the entire nation, interventions might be most effective if directed to regions with the majority of fatalities because they have the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/7156499-lightning-prevention-systems-paper-mills','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/7156499-lightning-prevention-systems-paper-mills"><span><span class="hlt">Lightning</span> prevention systems for paper mills</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Carpenter, R.B. Jr.</p> <p>1989-05-01</p> <p>Paper mills are increasingly relying on sensitive electronic equipment to control their operations. However, the sensitivity of these devices has made mills vulnerable to the effects of <span class="hlt">lightning</span> strokes. An interruption in the power supply or the destruction of delicate microcircuits can have devastating effects on mill productivity. The authors discuss how <span class="hlt">lightning</span> strokes can be prevented by a Dissipation Array system (DAS). During the past 17 years, the concept has been applied to a host of applications in regions with a high incidence of <span class="hlt">lightning</span> activity. With nearly 700 systems now installed, more than 4000 system-years of history havemore » been accumulated. Areas as large as 1 km{sup 2} and towers as high as 2000 ft have been protected and completely isolated from <span class="hlt">lightning</span> strokes. There have been very few failures, and in every case, the cause of the failure was determined and corrected.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMAE13A0336K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMAE13A0336K"><span><span class="hlt">Lightning</span> mapping and dual-polarization radar observations of electrified storms at Langmuir <span class="hlt">Laboratory</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Krehbiel, P. R.; Hyland, P. T.; Edens, H. E.; Rison, W.</p> <p>2013-12-01</p> <p>Observations being made at Langmuir <span class="hlt">Laboratory</span> with the NM Tech <span class="hlt">Lightning</span> Mapping Array (LMA) and the University of Oklahoma ARRC PX-1000 dual polarization X-band radar strongly confirm and expand upon the normal polarity tripolar electrical structure of central New Mexico storms. This is in sharp contrast with the anomalously electrified storm structures observed in northern Colorado during and subsequent to the 2012 DC3 field campaign, as seen with North Colorado LMA and CSU CHILL dual-polarization radar observations. In this presentation we focus on the New Mexico observations, and several modes in which the tripolar structure appears initially to develop and evolve with time. Central New Mexico storms are often prolific producers of negative cloud-to-ground (CG) flashes, but rarely produce positive CGs. By contrast, many or most north Colorado storms are CG-deficient, with the relatively few CG discharges being of predominantly positive polarity. In addition, NM storms commonly produce bolt-from-the-blue (BFB) negative CGs, whereas anomalously electrified Colorado storms produce none. The occurrence of BFBs is indicative of a relatively weak lower positive charge region, while the occurrence of normal downward -CGs is indicative of a somewhat stronger lower positive charge. The lack of -CGs in Colorado storms results from lower positive charge being a dominant storm charge that is elevated in altitude. These and other basic features of the electrically activity of storms, coupled with dual polarization and Doppler radar observations of hydrometeor types and motions, are leading to a better understanding of the storm electrification processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170000764','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170000764"><span>An Assessment of Land Surface and <span class="hlt">Lightning</span> Characteristics Associated with <span class="hlt">Lightning</span>-Initiated Wildfires</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Coy, James; Schultz, Christopher J.; Case, Jonathan L.</p> <p>2017-01-01</p> <p>Can we use modeled information of the land surface and characteristics of <span class="hlt">lightning</span> beyond flash occurrence to increase the identification and prediction of wildfires? Combine observed cloud-to-ground (CG) flashes with real-time land surface model output, and Compare data with areas where <span class="hlt">lightning</span> did not start a wildfire to determine what land surface conditions and <span class="hlt">lightning</span> characteristics were responsible for causing wildfires. Statistical differences between suspected fire-starters and non-fire-starters were peak-current dependent 0-10 cm Volumetric and Relative Soil Moisture comparisons were statistically dependent to at least the p = 0.05 independence level for both polarity flash types Suspected fire-starters typically occurred in areas of lower soil moisture than non-fire-starters. GVF value comparisons were only found to be statistically dependent for -CG flashes. However, random sampling of the -CG non-fire starter dataset revealed that this relationship may not always hold.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110024188','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110024188"><span><span class="hlt">Lightning</span> Protection and Instrumentation at Kennedy Space Center</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Colon, Jose L.</p> <p>2005-01-01</p> <p><span class="hlt">Lightning</span> is a natural phenomenon, but can be dangerous. Prevention of <span class="hlt">lightning</span> is a physical impossibility and total protection requires compromises on costs and effects, therefore prediction and measurements of the effects that might be produced by iightn:ing is a most at locat:ions where people or sensitive systems and equipment are exposed. This is the case of the launching pads for the Space Shuttle at Kennedy Space Center (KSC) of the National Aeronautics and Space Administration. This report summarizes lightring phenomena with a brief explanation of <span class="hlt">lightning</span> generation and <span class="hlt">lightning</span> activity as related to KSC. An analysis of the instrumentation used at the launching pads for measurements of <span class="hlt">lightning</span> effects with alternatives to improve the protection system and up-grade the actual instrumentation system is indicated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PhDT.........5C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PhDT.........5C"><span>Terrestrial gamma-ray flash production by <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carlson, Brant E.</p> <p></p> <p>Terrestrial gamma-ray flashes (TGFs) are brief flashes of gamma-rays originating in the Earth's atmosphere and observed by satellites. First observed in 1994 by the Burst And Transient Source Experiment on board the Compton Gamma-Ray Observatory, TGFs consist of one or more ˜1 ms pulses of gamma-rays with a total fluence of ˜1/cm2, typically observed when the satellite is near active thunderstorms. TGFs have subsequently been observed by other satellites to have a very hard spectrum (harder than dN/d E ∝ 1/ E ) that extends from below 25 keV to above 20 MeV. When good <span class="hlt">lightning</span> data exists, TGFs are closely associated with measurable <span class="hlt">lightning</span> discharge. Such discharges are typically observed to occur within 300 km of the sub-satellite point and within several milliseconds of the TGF observation. The production of these intense energetic bursts of photons is the puzzle addressed herein. The presence of high-energy photons implies a source of bremsstrahlung, while bremsstrahlung implies a source of energetic electrons. As TGFs are associated with <span class="hlt">lightning</span>, fields produced by <span class="hlt">lightning</span> are naturally suggested to accelerate these electrons. Initial ideas about TGF production involved electric fields high above thunderstorms as suggested by upper atmospheric <span class="hlt">lightning</span> research and the extreme energies required for lower-altitude sources. These fields, produced either quasi-statically by charges in the cloud and ionosphere or dynamically by radiation from <span class="hlt">lightning</span> strokes, can indeed drive TGF production, but the requirements on the source <span class="hlt">lightning</span> are too extreme and therefore not common enough to account for all existing observations. In this work, studies of satellite data, the physics of energetic electron and photon production, and consideration of <span class="hlt">lightning</span> physics motivate a new mechanism for TGF production by <span class="hlt">lightning</span> current pulses. This mechanism is then developed and used to make testable predictions. TGF data from satellite observations are compared</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850008036&hterms=microprocessor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmicroprocessor','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850008036&hterms=microprocessor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmicroprocessor"><span>Data and results of a <span class="hlt">laboratory</span> investigation of microprocessor upset caused by simulated <span class="hlt">lightning</span>-induced analog transients</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Belcastro, C. M.</p> <p>1984-01-01</p> <p>Advanced composite aircraft designs include fault-tolerant computer-based digital control systems with thigh reliability requirements for adverse as well as optimum operating environments. Since aircraft penetrate intense electromagnetic fields during thunderstorms, onboard computer systems maya be subjected to field-induced transient voltages and currents resulting in functional error modes which are collectively referred to as digital system upset. A methodology was developed for assessing the upset susceptibility of a computer system onboard an aircraft flying through a <span class="hlt">lightning</span> environment. Upset error modes in a general-purpose microprocessor were studied via tests which involved the random input of analog transients which model <span class="hlt">lightning</span>-induced signals onto interface lines of an 8080-based microcomputer from which upset error data were recorded. The application of Markov modeling to upset susceptibility estimation is discussed and a stochastic model development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title14-vol1/pdf/CFR-2013-title14-vol1-sec23-954.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title14-vol1/pdf/CFR-2013-title14-vol1-sec23-954.pdf"><span>14 CFR 23.954 - Fuel system <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-01-01</p> <p>... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Fuel system <span class="hlt">lightning</span> protection. 23.954... Fuel System § 23.954 Fuel system <span class="hlt">lightning</span> protection. The fuel system must be designed and arranged to prevent the ignition of fuel vapor within the system by— (a) Direct <span class="hlt">lightning</span> strikes to areas having a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title14-vol1/pdf/CFR-2012-title14-vol1-sec23-954.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title14-vol1/pdf/CFR-2012-title14-vol1-sec23-954.pdf"><span>14 CFR 23.954 - Fuel system <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-01-01</p> <p>... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Fuel system <span class="hlt">lightning</span> protection. 23.954... Fuel System § 23.954 Fuel system <span class="hlt">lightning</span> protection. The fuel system must be designed and arranged to prevent the ignition of fuel vapor within the system by— (a) Direct <span class="hlt">lightning</span> strikes to areas having a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title14-vol1/pdf/CFR-2010-title14-vol1-sec23-954.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title14-vol1/pdf/CFR-2010-title14-vol1-sec23-954.pdf"><span>14 CFR 23.954 - Fuel system <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-01-01</p> <p>... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel system <span class="hlt">lightning</span> protection. 23.954... Fuel System § 23.954 Fuel system <span class="hlt">lightning</span> protection. The fuel system must be designed and arranged to prevent the ignition of fuel vapor within the system by— (a) Direct <span class="hlt">lightning</span> strikes to areas having a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title14-vol1/pdf/CFR-2011-title14-vol1-sec23-954.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title14-vol1/pdf/CFR-2011-title14-vol1-sec23-954.pdf"><span>14 CFR 23.954 - Fuel system <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-01-01</p> <p>... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Fuel system <span class="hlt">lightning</span> protection. 23.954... Fuel System § 23.954 Fuel system <span class="hlt">lightning</span> protection. The fuel system must be designed and arranged to prevent the ignition of fuel vapor within the system by— (a) Direct <span class="hlt">lightning</span> strikes to areas having a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title14-vol1/pdf/CFR-2014-title14-vol1-sec23-954.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title14-vol1/pdf/CFR-2014-title14-vol1-sec23-954.pdf"><span>14 CFR 23.954 - Fuel system <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-01-01</p> <p>... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Fuel system <span class="hlt">lightning</span> protection. 23.954... Fuel System § 23.954 Fuel system <span class="hlt">lightning</span> protection. The fuel system must be designed and arranged to prevent the ignition of fuel vapor within the system by— (a) Direct <span class="hlt">lightning</span> strikes to areas having a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=lightning&pg=5&id=EJ351674','ERIC'); return false;" href="https://eric.ed.gov/?q=lightning&pg=5&id=EJ351674"><span>Protecting Your Park When <span class="hlt">Lightning</span> Strikes.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Frydenlund, Marvin M.</p> <p>1987-01-01</p> <p>A formula for assessing specific risk of <span class="hlt">lightning</span> strikes is provided. Recent legal cases are used to illustrate potential liability. Six actions park managers can take to minimize danger from <span class="hlt">lightning</span> are presented, and commonsense rules which should be publicly posted are listed. (MT)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMAE31B0433H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMAE31B0433H"><span>Preliminary Results form the Japanese Total <span class="hlt">Lightning</span> Network</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hobara, Y.; Ishii, H.; Kumagai, Y.; Liu, C.; Heckman, S.; Price, C. G.; Williams, E. R.</p> <p>2015-12-01</p> <p>We report on the initial observational results from the first Japanese Total <span class="hlt">Lightning</span> Detection Network (JTLN) in relation to severe weather phenomena. The University of Electro-Communications (UEC) has deployed the Earth Networks (EN) Total <span class="hlt">Lightning</span> System over Japan to carry out research on the relationship between thunderstorm activity and severe weather phenomena since 2013. In this paper we first demonstrate the current status of our new network followed by the initial scientific results. The <span class="hlt">lightning</span> jump algorithm was applied to our total <span class="hlt">lightning</span> data to study the relationship between total lighting activity and hazardous weather events such as gust fronts and tornadoes over land reported by the JMA (Japanese Meteorological Agency) in 2014. As a result, a clear increase in total lighting flash rate as well as <span class="hlt">lightning</span> jumps are observed prior to most hazardous weather events (~20 min) indicating potential usefulness for early warning in Japan. Furthermore we are going to demonstrate the relationship of total <span class="hlt">lightning</span> activities with meteorological radar data focusing particularly on Japanese Tornadic storms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMAE41A..02V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE41A..02V"><span>Cross-Referencing GLM and ISS-LIS with Ground-Based <span class="hlt">Lightning</span> Networks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Virts, K.; Blakeslee, R. J.; Goodman, S. J.; Koshak, W. J.</p> <p>2017-12-01</p> <p>The Geostationary <span class="hlt">Lightning</span> Mapper (GLM), in geostationary orbit aboard GOES-16 since late 2016, and the <span class="hlt">Lightning</span> Imaging Sensor (LIS), installed on the International Space Station in February 2017, provide observations of total <span class="hlt">lightning</span> activity from space. ISS-LIS samples the global tropics and mid-latitudes, while GLM observes the full thunderstorm life-cycle over the Americas and surrounding oceans. The launch of these instruments provides an unprecedented opportunity to compare <span class="hlt">lightning</span> observations across multiple space-based optical <span class="hlt">lightning</span> sensors. In this study, months of observations from GLM and ISS-LIS are cross-referenced with each other and with <span class="hlt">lightning</span> detected by the ground-based Earth Networks Global <span class="hlt">Lightning</span> Network (ENGLN) and the Vaisala Global <span class="hlt">Lightning</span> Dataset 360 (GLD360) throughout and beyond the GLM field-of-view. In addition to calibration/validation of the new satellite sensors, this study provides a statistical comparison of the characteristics of <span class="hlt">lightning</span> observed by the satellite and ground-based instruments, with an emphasis on the <span class="hlt">lightning</span> flashes uniquely identified by the satellites.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/864662','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/864662"><span>Detonator-activated <span class="hlt">ball</span> shutter</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>McWilliams, Roy A.; von Holle, William G.</p> <p>1983-01-01</p> <p>A detonator-activated <span class="hlt">ball</span> shutter for closing an aperture in about 300.mu. seconds. The <span class="hlt">ball</span> shutter containing an aperture through which light, etc., passes, is closed by firing a detonator which propels a projectile for rotating the <span class="hlt">ball</span> shutter, thereby blocking passage through the aperture.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/39379','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/39379"><span>Progress towards a <span class="hlt">lightning</span> ignition model for the Northern Rockies</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Paul Sopko; Don Latham</p> <p>2010-01-01</p> <p>We are in the process of constructing a <span class="hlt">lightning</span> ignition model specific to the Northern Rockies using fire occurrence, <span class="hlt">lightning</span> strike, ecoregion, and historical weather, NFDRS (National Fire Danger Rating System), <span class="hlt">lightning</span> efficiency and <span class="hlt">lightning</span> "possibility" data. Daily grids for each of these categories were reconstructed for the 2003 fire season (...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000105169&hterms=Law+order&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DLaw%2Border','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000105169&hterms=Law+order&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DLaw%2Border"><span><span class="hlt">Lightning</span> Scaling Laws Revisited</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Boccippio, D. J.; Arnold, James E. (Technical Monitor)</p> <p>2000-01-01</p> <p>Scaling laws relating storm electrical generator power (and hence <span class="hlt">lightning</span> flash rate) to charge transport velocity and storm geometry were originally posed by Vonnegut (1963). These laws were later simplified to yield simple parameterizations for <span class="hlt">lightning</span> based upon cloud top height, with separate parameterizations derived over land and ocean. It is demonstrated that the most recent ocean parameterization: (1) yields predictions of storm updraft velocity which appear inconsistent with observation, and (2) is formally inconsistent with the theory from which it purports to derive. Revised formulations consistent with Vonnegut's original framework are presented. These demonstrate that Vonnegut's theory is, to first order, consistent with observation. The implications of assuming that flash rate is set by the electrical generator power, rather than the electrical generator current, are examined. The two approaches yield significantly different predictions about the dependence of charge transfer per flash on storm dimensions, which should be empirically testable. The two approaches also differ significantly in their explanation of regional variability in <span class="hlt">lightning</span> observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20090033131','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20090033131"><span>Developing an Enhanced <span class="hlt">Lightning</span> Jump Algorithm for Operational Use</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schultz, Christopher J.; Petersen, Walter A.; Carey, Lawrence D.</p> <p>2009-01-01</p> <p>Overall Goals: 1. Build on the <span class="hlt">lightning</span> jump framework set through previous studies. 2. Understand what typically occurs in nonsevere convection with respect to increases in <span class="hlt">lightning</span>. 3. Ultimately develop a <span class="hlt">lightning</span> jump algorithm for use on the Geostationary <span class="hlt">Lightning</span> Mapper (GLM). 4 <span class="hlt">Lightning</span> jump algorithm configurations were developed (2(sigma), 3(sigma), Threshold 10 and Threshold 8). 5 algorithms were tested on a population of 47 nonsevere and 38 severe thunderstorms. Results indicate that the 2(sigma) algorithm performed best over the entire thunderstorm sample set with a POD of 87%, a far of 35%, a CSI of 59% and a HSS of 75%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MAP...128..303B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MAP...128..303B"><span><span class="hlt">Lightning</span> characteristics of derecho producing mesoscale convective systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bentley, Mace L.; Franks, John R.; Suranovic, Katelyn R.; Barbachem, Brent; Cannon, Declan; Cooper, Stonie R.</p> <p>2016-06-01</p> <p>Derechos, or widespread, convectively induced wind storms, are a common warm season phenomenon in the Central and Eastern United States. These damaging and severe weather events are known to sweep quickly across large spatial regions of more than 400 km and produce wind speeds exceeding 121 km h-1. Although extensive research concerning derechos and their parent mesoscale convective systems already exists, there have been few investigations of the spatial and temporal distribution of associated cloud-to-ground <span class="hlt">lightning</span> with these events. This study analyzes twenty warm season (May through August) derecho events between 2003 and 2013 in an effort to discern their <span class="hlt">lightning</span> characteristics. Data used in the study included cloud-to-ground flash data derived from the National <span class="hlt">Lightning</span> Detection Network, WSR-88D imagery from the University Corporation for Atmospheric Research, and damaging wind report data obtained from the Storm Prediction Center. A spatial and temporal analysis was conducted by incorporating these data into a geographic information system to determine the distribution and <span class="hlt">lightning</span> characteristics of the environments of derecho producing mesoscale convective systems. Primary foci of this research include: (1) finding the approximate size of the <span class="hlt">lightning</span> activity region for individual and combined event(s); (2) determining the intensity of each event by examining the density and polarity of <span class="hlt">lightning</span> flashes; (3) locating areas of highest <span class="hlt">lightning</span> flash density; and (4) to provide a <span class="hlt">lightning</span> spatial analysis that outlines the temporal and spatial distribution of flash activity for particularly strong derecho producing thunderstorm episodes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20030062245&hterms=inversion&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dinversion','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20030062245&hterms=inversion&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dinversion"><span>Mathematical Inversion of <span class="hlt">Lightning</span> Data: Techniques and Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William</p> <p>2003-01-01</p> <p>A survey of some interesting mathematical inversion studies dealing with radio, optical, and electrostatic measurements of <span class="hlt">lightning</span> are presented. A discussion of why NASA is interested in <span class="hlt">lightning</span>, what specific physical properties of <span class="hlt">lightning</span> are retrieved, and what mathematical techniques are used to perform the retrievals are discussed. In particular, a relatively new multi-station VHF time-of-arrival (TOA) antenna network is now on-line in Northern Alabama and will be discussed. The network, called the <span class="hlt">Lightning</span> Mapping Array (LMA), employs GPS timing and detects VHF radiation from discrete segments (effectively point emitters) that comprise the channel of <span class="hlt">lightning</span> strokes within cloud and ground flashes. The LMA supports on-going ground-validation activities of the low Earth orbiting <span class="hlt">Lightning</span> Imaging Sensor (LIS) satellite developed at NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama. The LMA also provides detailed studies of the distribution and evolution of thunderstorms and <span class="hlt">lightning</span> in the Tennessee Valley, and offers interesting comparisons with other meteorological/geophysical datasets. In order to take full advantage of these benefits, it is essential that the LMA channel mapping accuracy (in both space and time) be fully characterized and optimized. A new channel mapping retrieval algorithm is introduced for this purpose. To characterize the spatial distribution of retrieval errors, the algorithm has been applied to analyze literally tens of millions of computer-simulated <span class="hlt">lightning</span> VHF point sources that have been placed at various ranges, azimuths, and altitudes relative to the LMA network. Statistical results are conveniently summarized in high-resolution, color-coded, error maps.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890054520&hterms=rust&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Drust','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890054520&hterms=rust&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Drust"><span>A photoelectric technique for measuring <span class="hlt">lightning</span>-channel propagation velocities from a mobile <span class="hlt">laboratory</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mach, Douglas M.; Rust, W. David</p> <p>1989-01-01</p> <p>The present device for <span class="hlt">lightning</span> channel propagation-velocity determination employs eight photodetectors mounted behind precision horizontal slits in the focal plane of a photographic camera lens. The eight photodetector pulses, IRIG-B time, and slow and fast electric field-change waveforms are recorded on a 14-track analog tape recorder. A comparison of the present results with those obtained by a streaking camera shows no significant differences between the velocities obtained from the same strokes with the two systems; neither is there any difference in pulse characteristics or in the velocities calculated from them.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/7246409','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/biblio/7246409"><span>Detonator-activated <span class="hlt">ball</span> shutter</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>McWilliams, R.A.; Holle, W.G. von.</p> <p>1983-08-16</p> <p>A detonator-activated <span class="hlt">ball</span> shutter for closing an aperture in about 300[mu] seconds. The <span class="hlt">ball</span> shutter containing an aperture through which light, etc., passes, is closed by firing a detonator which propels a projectile for rotating the <span class="hlt">ball</span> shutter, thereby blocking passage through the aperture. 3 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APJAS..50..133S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APJAS..50..133S"><span>Statistical analysis of <span class="hlt">lightning</span> electric field measured under Malaysian condition</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Salimi, Behnam; Mehranzamir, Kamyar; Abdul-Malek, Zulkurnain</p> <p>2014-02-01</p> <p><span class="hlt">Lightning</span> is an electrical discharge during thunderstorms that can be either within clouds (Inter-Cloud), or between clouds and ground (Cloud-Ground). The <span class="hlt">Lightning</span> characteristics and their statistical information are the foundation for the design of <span class="hlt">lightning</span> protection system as well as for the calculation of <span class="hlt">lightning</span> radiated fields. Nowadays, there are various techniques to detect <span class="hlt">lightning</span> signals and to determine various parameters produced by a <span class="hlt">lightning</span> flash. Each technique provides its own claimed performances. In this paper, the characteristics of captured broadband electric fields generated by cloud-to-ground <span class="hlt">lightning</span> discharges in South of Malaysia are analyzed. A total of 130 cloud-to-ground <span class="hlt">lightning</span> flashes from 3 separate thunderstorm events (each event lasts for about 4-5 hours) were examined. Statistical analyses of the following signal parameters were presented: preliminary breakdown pulse train time duration, time interval between preliminary breakdowns and return stroke, multiplicity of stroke, and percentages of single stroke only. The BIL model is also introduced to characterize the <span class="hlt">lightning</span> signature patterns. Observations on the statistical analyses show that about 79% of <span class="hlt">lightning</span> signals fit well with the BIL model. The maximum and minimum of preliminary breakdown time duration of the observed <span class="hlt">lightning</span> signals are 84 ms and 560 us, respectively. The findings of the statistical results show that 7.6% of the flashes were single stroke flashes, and the maximum number of strokes recorded was 14 multiple strokes per flash. A preliminary breakdown signature in more than 95% of the flashes can be identified.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title30-vol1/pdf/CFR-2014-title30-vol1-sec56-12065.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title30-vol1/pdf/CFR-2014-title30-vol1-sec56-12065.pdf"><span>30 CFR 56.12065 - Short circuit and <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-07-01</p> <p>... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Short circuit and <span class="hlt">lightning</span> protection. 56... Electricity § 56.12065 Short circuit and <span class="hlt">lightning</span> protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and <span class="hlt">lightning</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title30-vol1/pdf/CFR-2013-title30-vol1-sec56-12065.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title30-vol1/pdf/CFR-2013-title30-vol1-sec56-12065.pdf"><span>30 CFR 56.12065 - Short circuit and <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-07-01</p> <p>... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Short circuit and <span class="hlt">lightning</span> protection. 56... Electricity § 56.12065 Short circuit and <span class="hlt">lightning</span> protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and <span class="hlt">lightning</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title30-vol1/pdf/CFR-2012-title30-vol1-sec56-12065.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title30-vol1/pdf/CFR-2012-title30-vol1-sec56-12065.pdf"><span>30 CFR 56.12065 - Short circuit and <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-07-01</p> <p>... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Short circuit and <span class="hlt">lightning</span> protection. 56... Electricity § 56.12065 Short circuit and <span class="hlt">lightning</span> protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and <span class="hlt">lightning</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title30-vol1/pdf/CFR-2011-title30-vol1-sec56-12065.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title30-vol1/pdf/CFR-2011-title30-vol1-sec56-12065.pdf"><span>30 CFR 56.12065 - Short circuit and <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-07-01</p> <p>... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Short circuit and <span class="hlt">lightning</span> protection. 56... Electricity § 56.12065 Short circuit and <span class="hlt">lightning</span> protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and <span class="hlt">lightning</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title30-vol1/pdf/CFR-2010-title30-vol1-sec56-12065.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title30-vol1/pdf/CFR-2010-title30-vol1-sec56-12065.pdf"><span>30 CFR 56.12065 - Short circuit and <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-07-01</p> <p>... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit and <span class="hlt">lightning</span> protection. 56... Electricity § 56.12065 Short circuit and <span class="hlt">lightning</span> protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and <span class="hlt">lightning</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023319','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023319"><span>A transportable 50 kA dual mode <span class="hlt">lightning</span> simulator</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Salisbury, K.; Lloyd, S.; Chen, Y. G.</p> <p>1991-01-01</p> <p>A transportable <span class="hlt">lightning</span> simulator was designed, built and tested, which is capable of delivering more than 50 kA to an 8 micro-H test object. The simulator was designed to be a versatile device in the <span class="hlt">lightning</span> <span class="hlt">laboratory</span> while meeting the requirements of MIL-STD-1757A for component E current waveforms. The system is capable of operating in either a ringing mode with a Q greater than 5 and a nominal frequency of 160 kHz, or a unipolar mode with no hardware configuration changes. The ringing mode is obtained by the LCR series circuit formed by the pulse generator and test object. The unipolar mode is obtained by closing an electrically triggered crowbar switch at peak current. The simulator exceeds the peak current requirement and rate of rise requirements for MIL-STD-1757A in both the ringing and unipolar modes. The pulse half width in the unipolar mode is in excess of 50 microsec and the action is in excess of 10(exp 5) A(exp 2)s. The design, component values, and test results are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFMAE43B0273H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFMAE43B0273H"><span>Combined VLF and VHF <span class="hlt">lightning</span> observations of Hurricane Rita landfall</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Henderson, B. G.; Suszcynsky, D. M.; Wiens, K. C.; Hamlin, T.; Jeffery, C. A.; Orville, R. E.</p> <p>2009-12-01</p> <p>Hurricane Rita displayed abundant <span class="hlt">lightning</span> in its northern eyewall as it made landfall at 0740 UTC 24 Sep 2005 near the Texas/Louisiana border. For this work, we combined VHF and VLF <span class="hlt">lightning</span> data from Hurricane Rita, along with radar observations from Gulf Coast WSR-88D stations, for the purpose of demonstrating the combined utility of these two spectral regions for hurricane <span class="hlt">lightning</span> monitoring. <span class="hlt">Lightning</span> is a direct consequence of the electrification and breakdown processes that take place during the convective stages of thunderstorm development. As Rita approached the Gulf coast, the VHF <span class="hlt">lightning</span> emissions were distinctly periodic with a period of 1.5 to 2 hours, which is consistent with the rotational period of hurricanes. VLF <span class="hlt">lightning</span> emissions, measured by LASA and NLDN, were present in some of these VHF bursts but not all of them. At landfall, there was a significant increase in <span class="hlt">lightning</span> emissions, accompanied by a significant convective surge observed in radar. Furthermore, VLF and VHF <span class="hlt">lightning</span> source heights clearly increase as a function of time. The evolution of the IC/CG ratio is consistent with that seen in thunderstorms, showing a dominance of IC activity during storm development, followed by an increase in CG activity at the storm’s peak. The periodic VHF <span class="hlt">lightning</span> events are correlated with increases in convective growth (quantified by the volume of radar echo >40 dB) above 7 km altitude. VLF can discriminate between <span class="hlt">lightning</span> types, and in the LASA data, Rita landfall <span class="hlt">lightning</span> activity was dominated by Narrow Bi-polar Events (NBEs)—high-energy, high-altitude, compact intra-cloud discharges. The opportunity to locate NBE <span class="hlt">lightning</span> sources in altitude may be particularly useful in quantifying the vertical extent (strength) of the convective development and in possibly deducing vertical charge distributions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1756127','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1756127"><span><span class="hlt">Lightning</span> injuries during snowy conditions</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cherington, M.; Breed, D. W.; Yarnell, P. R.; Smith, W. E.</p> <p>1998-01-01</p> <p>Skiers and other snow sports enthusiasts can become <span class="hlt">lightning</span> casualties. Two such accidents are reported, one being fatal. There are fewer warning signals of impending <span class="hlt">lightning</span> strikes in winter-like conditions. However, outdoor activists should be aware of at least two suspicious clues: the appearance of convective clouds, and the presence of graupel (snow pellets) during precipitation. 




 PMID:9865407</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4165329','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4165329"><span>Calculation of Transient Potential Rise on the Wind Turbine Struck by <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Xiaoqing, Zhang</p> <p>2014-01-01</p> <p>A circuit model is proposed in this paper for calculating the transient potential rise on the wind turbine struck by <span class="hlt">lightning</span>. The model integrates the blade, sliding contact site, and tower and grounding system of the wind turbine into an equivalent circuit. The <span class="hlt">lightning</span> current path from the attachment point to the ground can be fully described by the equivalent circuit. The transient potential responses are obtained in the different positions on the wind turbine by solving the circuit equations. In order to check the validity of the model, the <span class="hlt">laboratory</span> measurement is made with a reduced-scale wind turbine. The measured potential waveform is compared with the calculated one and a better agreement is shown between them. The practical applicability of the model is also examined by a numerical example of a 2 MW Chinese-built wind turbine. PMID:25254231</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25254231','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25254231"><span>Calculation of transient potential rise on the wind turbine struck by <span class="hlt">lightning</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xiaoqing, Zhang</p> <p>2014-01-01</p> <p>A circuit model is proposed in this paper for calculating the transient potential rise on the wind turbine struck by <span class="hlt">lightning</span>. The model integrates the blade, sliding contact site, and tower and grounding system of the wind turbine into an equivalent circuit. The <span class="hlt">lightning</span> current path from the attachment point to the ground can be fully described by the equivalent circuit. The transient potential responses are obtained in the different positions on the wind turbine by solving the circuit equations. In order to check the validity of the model, the <span class="hlt">laboratory</span> measurement is made with a reduced-scale wind turbine. The measured potential waveform is compared with the calculated one and a better agreement is shown between them. The practical applicability of the model is also examined by a numerical example of a 2 MW Chinese-built wind turbine.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title14-vol1/pdf/CFR-2011-title14-vol1-sec35-38.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title14-vol1/pdf/CFR-2011-title14-vol1-sec35-38.pdf"><span>14 CFR 35.38 - <span class="hlt">Lightning</span> strike.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-01-01</p> <p>... STANDARDS: PROPELLERS Tests and Inspections § 35.38 <span class="hlt">Lightning</span> strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a <span class="hlt">lightning</span> strike without causing a major or hazardous propeller effect. The limit to which the propeller has...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title14-vol1/pdf/CFR-2010-title14-vol1-sec35-38.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title14-vol1/pdf/CFR-2010-title14-vol1-sec35-38.pdf"><span>14 CFR 35.38 - <span class="hlt">Lightning</span> strike.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-01-01</p> <p>... STANDARDS: PROPELLERS Tests and Inspections § 35.38 <span class="hlt">Lightning</span> strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a <span class="hlt">lightning</span> strike without causing a major or hazardous propeller effect. The limit to which the propeller has...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title14-vol1/pdf/CFR-2013-title14-vol1-sec35-38.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title14-vol1/pdf/CFR-2013-title14-vol1-sec35-38.pdf"><span>14 CFR 35.38 - <span class="hlt">Lightning</span> strike.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-01-01</p> <p>... STANDARDS: PROPELLERS Tests and Inspections § 35.38 <span class="hlt">Lightning</span> strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a <span class="hlt">lightning</span> strike without causing a major or hazardous propeller effect. The limit to which the propeller has...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title14-vol1/pdf/CFR-2012-title14-vol1-sec35-38.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title14-vol1/pdf/CFR-2012-title14-vol1-sec35-38.pdf"><span>14 CFR 35.38 - <span class="hlt">Lightning</span> strike.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-01-01</p> <p>... STANDARDS: PROPELLERS Tests and Inspections § 35.38 <span class="hlt">Lightning</span> strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a <span class="hlt">lightning</span> strike without causing a major or hazardous propeller effect. The limit to which the propeller has...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title14-vol1/pdf/CFR-2014-title14-vol1-sec35-38.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title14-vol1/pdf/CFR-2014-title14-vol1-sec35-38.pdf"><span>14 CFR 35.38 - <span class="hlt">Lightning</span> strike.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-01-01</p> <p>... STANDARDS: PROPELLERS Tests and Inspections § 35.38 <span class="hlt">Lightning</span> strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a <span class="hlt">lightning</span> strike without causing a major or hazardous propeller effect. The limit to which the propeller has...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1580017','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1580017"><span><span class="hlt">Lightning</span>-related mortality and morbidity in Florida.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Duclos, P J; Sanderson, L M; Klontz, K C</p> <p>1990-01-01</p> <p>Cases of <span class="hlt">lightning</span>-related deaths and injuries that occurred in Florida in 1978-87 were reviewed to determine the factors involved, to quantify the morbidity and mortality related to <span class="hlt">lightning</span> strikes, and to describe epidemiologically the injuries and circumstances involved. Statewide information on deaths was obtained from death certificates, autopsy reports, and investigative reports. Information about morbidity was obtained from the Florida Hospital Cost Containment Board data base and the National Climatic Data Center data base for all Florida counties, as well as from hospitals in selected counties. <span class="hlt">Lightning</span>-related deaths totaled 101 in Florida during the period 1978-87, an annual average of 10.1. Eight percent of the victims were from other States. The overall yearly death rate for State residents was 0.09 per 100,000 population, with the highest rate being that for men aged 15-19 years, 0.38 per 100,000. Thirteen percent of victims were females. The ratio of <span class="hlt">lightning</span>-related injuries to deaths in Florida was estimated at about four to one. Thirty percent of all deaths were occupationally related. The first strikes of <span class="hlt">lightning</span> from a thunderstorm may be the most dangerous, not in terms of impact, but because of the element of surprise. During thunderstorms, people may seek shelter under isolated trees because they believe erroneously that a tree offers protection from <span class="hlt">lightning</span>, or perhaps because their top priority is to escape from rain rather than <span class="hlt">lightning</span>. People may not seek adequate shelter during thunderstorms because they do not know the dangers of remaining outdoors or their judgment is impaired by drugs or alcohol. PMID:2113687</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/2113687','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/2113687"><span><span class="hlt">Lightning</span>-related mortality and morbidity in Florida.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Duclos, P J; Sanderson, L M; Klontz, K C</p> <p>1990-01-01</p> <p>Cases of <span class="hlt">lightning</span>-related deaths and injuries that occurred in Florida in 1978-87 were reviewed to determine the factors involved, to quantify the morbidity and mortality related to <span class="hlt">lightning</span> strikes, and to describe epidemiologically the injuries and circumstances involved. Statewide information on deaths was obtained from death certificates, autopsy reports, and investigative reports. Information about morbidity was obtained from the Florida Hospital Cost Containment Board data base and the National Climatic Data Center data base for all Florida counties, as well as from hospitals in selected counties. <span class="hlt">Lightning</span>-related deaths totaled 101 in Florida during the period 1978-87, an annual average of 10.1. Eight percent of the victims were from other States. The overall yearly death rate for State residents was 0.09 per 100,000 population, with the highest rate being that for men aged 15-19 years, 0.38 per 100,000. Thirteen percent of victims were females. The ratio of <span class="hlt">lightning</span>-related injuries to deaths in Florida was estimated at about four to one. Thirty percent of all deaths were occupationally related. The first strikes of <span class="hlt">lightning</span> from a thunderstorm may be the most dangerous, not in terms of impact, but because of the element of surprise. During thunderstorms, people may seek shelter under isolated trees because they believe erroneously that a tree offers protection from <span class="hlt">lightning</span>, or perhaps because their top priority is to escape from rain rather than <span class="hlt">lightning</span>. People may not seek adequate shelter during thunderstorms because they do not know the dangers of remaining outdoors or their judgment is impaired by drugs or alcohol.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20030111776&hterms=quantitative+data+analysis&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dquantitative%2Bdata%2Banalysis','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20030111776&hterms=quantitative+data+analysis&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dquantitative%2Bdata%2Banalysis"><span><span class="hlt">Lightning</span> and Precipitation: Observational Analysis of LIS and PR</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Adamo, C.; Solomon, R.; Goodman, S.; Dietrich, S.; Mugnai, A.</p> <p>2003-01-01</p> <p><span class="hlt">Lightning</span> flash rate can identify areas of convective rainfall when the storms are dominated by ice-phase precipitation. Modeling and observational studies indicate that cloud electrification and microphysics are very closely related and it is of great interest to understand the relationship between <span class="hlt">lightning</span> and cloud microphysical quantities. Analyzing data from the <span class="hlt">Lightning</span> Image Sensor (LIS) and the Precipitation Radar (PR), we show a quantitative relationship between microphysical characteristics of thunderclouds and <span class="hlt">lightning</span> flash rate. We have performed a complete analysis of all data available over the Mediterranean during the TRMM mission and show a range of reflective profiles as a function of <span class="hlt">lightning</span> activity for both convective and stratiform regimes as well as seasonal variations. Due to the increasing global coverage of <span class="hlt">lightning</span> detection networks, this kind of study can used to extend the knowledge about thunderstorms and discriminate between different regimes in regions where radar measurements are readilly available.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMAE11A..08C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE11A..08C"><span>Storm-based Cloud-to-Ground <span class="hlt">Lightning</span> Probabilities and Warnings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Calhoun, K. M.; Meyer, T.; Kingfield, D.</p> <p>2017-12-01</p> <p>A new cloud-to-ground (CG) <span class="hlt">lightning</span> probability algorithm has been developed using machine-learning methods. With storm-based inputs of Earth Networks' in-cloud <span class="hlt">lightning</span>, Vaisala's CG <span class="hlt">lightning</span>, multi-radar/multi-sensor (MRMS) radar derived products including the Maximum Expected Size of Hail (MESH) and Vertically Integrated Liquid (VIL), and near storm environmental data including lapse rate and CAPE, a random forest algorithm was trained to produce probabilities of CG <span class="hlt">lightning</span> up to one-hour in advance. As part of the Prototype Probabilistic Hazard Information experiment in the Hazardous Weather Testbed in 2016 and 2017, National Weather Service forecasters were asked to use this CG <span class="hlt">lightning</span> probability guidance to create rapidly updating probability grids and warnings for the threat of CG <span class="hlt">lightning</span> for 0-60 minutes. The output from forecasters was shared with end-users, including emergency managers and broadcast meteorologists, as part of an integrated warning team.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23173444','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23173444"><span>[Relationships of forest fire with <span class="hlt">lightning</span> in Daxing' anling Mountains, Northeast China].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lei, Xiao-Li; Zhou, Guang-Sheng; Jia, Bing-Rui; Li, Shuai</p> <p>2012-07-01</p> <p>Forest fire is an important factor affecting forest ecosystem succession. Recently, forest fire, especially forest <span class="hlt">lightning</span> fire, shows an increasing trend under global warming. To study the relationships of forest fire with <span class="hlt">lightning</span> is essential to accurately predict the forest fire in time. Daxing' anling Mountains is a region with high frequency of forest <span class="hlt">lightning</span> fire in China, and an important experiment site to study the relationships of forest fire with <span class="hlt">lightning</span>. Based on the forest fire records and the corresponding <span class="hlt">lightning</span> and meteorological observation data in the Mountains from 1966 to 2007, this paper analyzed the relationships of forest fire with <span class="hlt">lightning</span> in this region. In the period of 1966-2007, both the <span class="hlt">lightning</span> fire number and the fired forest area in this region increased significantly. The meteorological factors affecting the forest lighting fire were related to temporal scales. At yearly scale, the forest <span class="hlt">lightning</span> fire was significantly correlated with precipitation, with a correlation coefficient of -0.489; at monthly scale, it had a significant correlation with air temperature, the correlation coefficient being 0.18. The relationship of the forest <span class="hlt">lightning</span> fire with <span class="hlt">lightning</span> was also related to temporal scales. At yearly scale, there was no significant correlation between them; at monthly scale, the forest <span class="hlt">lightning</span> fire was strongly correlated with <span class="hlt">lightning</span> and affected by precipitation; at daily scale, a positive correlation was observed between forest <span class="hlt">lightning</span> fire and <span class="hlt">lightning</span> when the precipitation was less than 5 mm. According to these findings, a fire danger index based on ADTD <span class="hlt">lightning</span> detection data was established, and a forest <span class="hlt">lightning</span> fire forecast model was developed. The prediction accuracy of this model for the forest <span class="hlt">lightning</span> fire in Daxing' anling Mountains in 2005-2007 was > 80%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820000324&hterms=appliances&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dappliances','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820000324&hterms=appliances&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dappliances"><span>Inserts Automatically Lubricate <span class="hlt">Ball</span> Bearings</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hager, J. A.</p> <p>1983-01-01</p> <p>Inserts on <span class="hlt">ball</span>-separator ring of <span class="hlt">ball</span> bearings provide continuous film of lubricant on <span class="hlt">ball</span> surfaces. Inserts are machined or molded. Small inserts in <span class="hlt">ball</span> pockets provide steady supply of lubricant. Technique is utilized on equipment for which maintenance is often poor and lubrication interval is uncertain, such as household appliances, automobiles, and marine engines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD0603089','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD0603089"><span>RELATIONS BETWEEN <span class="hlt">LIGHTNING</span> DISCHARGES AND DIFFERENT TYPES OF MUSICAL ATMOSPHERICS,</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p></p> <p>Recording cathode-ray oscillographs were used for the analysis of the <span class="hlt">lightning</span> discharges whose relations to musical atmospherics were investigated...of the <span class="hlt">lightning</span> discharges investigated. Through comparative harmonic analyses it was shown that <span class="hlt">lightning</span> discharges producing musical atmospherics...followed by multiple whistlers. An investigation was made of correlations between <span class="hlt">lightning</span> discharges and musical atmospherics of unusual and irregular</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1725191','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1725191"><span>A controlled study on batted <span class="hlt">ball</span> speed and available pitcher reaction time in slowpitch softball</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>McDowell, M; Ciocco, M</p> <p>2005-01-01</p> <p>Objectives: To investigate safety risks in slowpitch softball by conducting <span class="hlt">laboratory</span> and experimental studies on the performance of high tech softball bats with polyurethane softballs. To compare the results with the recommended safety standards. Methods: ASTM standard compression testing of seven softball models was conducted. Using these seven softball models, bat/<span class="hlt">ball</span> impact testing was performed using seven adult male softball players and six high tech softball bat models to determine mean batted <span class="hlt">ball</span> speeds. Over 500 bat/<span class="hlt">ball</span> impact measurements were recorded and analysed. Available pitcher reaction time was calculated from the mean batted <span class="hlt">ball</span> speed measurements. Results: According to the United States Specialty Sports Association and the Amateur Softball Association, the maximum initial batted <span class="hlt">ball</span> speed should be 137.2 km/h, which corresponds to a minimum pitcher reaction time of 0.420 second. These experiments produced mean batted <span class="hlt">ball</span> speeds of 134.0–159.7 km/h, which correspond to available pitcher reaction times of 0.409–0.361 second. Conclusion: The use of high tech softball bats with polyurethane softballs can result in batted <span class="hlt">ball</span> speeds that exceed the recommended safety limits, which correspond to decreased available pitcher reaction times. PMID:15793092</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150000574','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150000574"><span><span class="hlt">Lightning</span> Current Measurement with Fiber-Optic Sensor</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.; Mata, Carlos T.; Mata, Angel G.; Snyder, Gary P.</p> <p>2014-01-01</p> <p>A fiber-optic current sensor is successfully developed with many potential applications for electric current measurement. Originally developed for in-flight <span class="hlt">lightning</span> measurement, the sensor utilizes Faraday Effect in an optical fiber. The Faraday Effect causes linear light polarization in a fiber to rotate when the fiber is exposed to a magnetic field. The polarization change is detected using a reflective polarimetric scheme. Forming fiber loops and applying Ampere's law, measuring the total light rotation results in the determination of the total current enclosed. The sensor is conformable to complex structure geometry. It is also non-conductive and immune to electromagnetic interference, saturation or hysteresis. Installation is non-intrusive, and the sensor can be safely routed through flammable areas. Two similar sensor systems are described in this paper. The first system operates at 1310nm laser wavelength and is capable of measuring approximately 300 A - 300 kA, a 60 dB range. <span class="hlt">Laboratory</span> validation results of aircraft lighting direct and in-direct effect current amplitudes are reported for this sensor. The second system operates at 1550nm wavelength and can measure about 400 A - 400 kA. Triggered-<span class="hlt">lightning</span> measurement data are presented for this system. Good results are achieved in all cases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRD..123.2628V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRD..123.2628V"><span>Optimizing Precipitation Thresholds for Best Correlation Between Dry <span class="hlt">Lightning</span> and Wildfires</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vant-Hull, Brian; Thompson, Tollisha; Koshak, William</p> <p>2018-03-01</p> <p>This work examines how to adjust the definition of "dry <span class="hlt">lightning</span>" in order to optimize the correlation between dry <span class="hlt">lightning</span> flash count and the climatology of large (>400 km2) <span class="hlt">lightning</span>-ignited wildfires over the contiguous United States (CONUS). The National <span class="hlt">Lightning</span> Detection Network™ and National Centers for Environmental Prediction Stage IV radar-based, gauge-adjusted precipitation data are used to form climatic data sets. For a 13 year analysis period over CONUS, a correlation of 0.88 is found between annual totals of wildfires and dry <span class="hlt">lightning</span>. This optimal correlation is found by defining dry <span class="hlt">lightning</span> as follows: on a 0.1° hourly grid, a precipitation threshold of no more than 0.3 mm may accumulate during any hour over a period of 3-4 days preceding the flash. Regional optimized definitions vary. When annual totals are analyzed as done here, no clear advantage is found by weighting positive polarity cloud-to-ground (+CG) <span class="hlt">lightning</span> differently than -CG <span class="hlt">lightning</span>. The high variability of dry <span class="hlt">lightning</span> relative to the precipitation and <span class="hlt">lightning</span> from which it is derived suggests it would be an independent and useful climate indicator.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A33G3278H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A33G3278H"><span>Estimating <span class="hlt">Lightning</span> NOx Emissions for Regional Air Quality Modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Holloway, T.; Scotty, E.; Harkey, M.</p> <p>2014-12-01</p> <p><span class="hlt">Lightning</span> emissions have long been recognized as an important source of nitrogen oxides (NOx) on a global scale, and an essential emission component for global atmospheric chemistry models. However, only in recent years have regional air quality models incorporated <span class="hlt">lightning</span> NOx emissions into simulations. The growth in regional modeling of <span class="hlt">lightning</span> emissions has been driven in part by comparisons with satellite-derived estimates of column NO2, especially from the Ozone Monitoring Instrument (OMI) aboard the Aura satellite. We present and evaluate a <span class="hlt">lightning</span> inventory for the EPA Community Multiscale Air Quality (CMAQ) model. Our approach follows Koo et al. [2010] in the approach to spatially and temporally allocating a given total value based on cloud-top height and convective precipitation. However, we consider alternate total NOx emission values (which translate into alternate <span class="hlt">lightning</span> emission factors) based on a review of the literature and performance evaluation against OMI NO2 for July 2007 conditions over the U.S. and parts of Canada and Mexico. The vertical distribution of <span class="hlt">lightning</span> emissions follow a bimodal distribution from Allen et al. [2012] calculated over 27 vertical model layers. Total <span class="hlt">lightning</span> NO emissions for July 2007 show the highest above-land emissions in Florida, southeastern Texas and southern Louisiana. Although agreement with OMI NO2 across the domain varied significantly depending on <span class="hlt">lightning</span> NOx assumptions, agreement among the simulations at ground-based NO2 monitors from the EPA Air Quality System database showed no meaningful sensitivity to <span class="hlt">lightning</span> NOx. Emissions are compared with prior studies, which find similar distribution patterns, but a wide range of calculated magnitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830003391','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830003391"><span>Interpretation methodology and analysis of in-flight <span class="hlt">lightning</span> data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rudolph, T.; Perala, R. A.</p> <p>1982-01-01</p> <p>A methodology is presented whereby electromagnetic measurements of inflight <span class="hlt">lightning</span> stroke data can be understood and extended to other aircraft. Recent measurements made on the NASA F106B aircraft indicate that sophisticated numerical techniques and new developments in corona modeling are required to fully understand the data. Thus the problem is nontrivial and successful interpretation can lead to a significant understanding of the <span class="hlt">lightning</span>/aircraft interaction event. This is of particular importance because of the problem of <span class="hlt">lightning</span> induced transient upset of new technology low level microcircuitry which is being used in increasing quantities in modern and future avionics. Inflight <span class="hlt">lightning</span> data is analyzed and <span class="hlt">lightning</span> environments incident upon the F106B are determined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21532036-study-transport-parameters-cloud-lightning-plasmas','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21532036-study-transport-parameters-cloud-lightning-plasmas"><span>Study of the transport parameters of cloud <span class="hlt">lightning</span> plasmas</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Chang, Z. S.; Yuan, P.; Zhao, N.</p> <p>2010-11-15</p> <p>Three spectra of cloud <span class="hlt">lightning</span> have been acquired in Tibet (China) using a slitless grating spectrograph. The electrical conductivity, the electron thermal conductivity, and the electron thermal diffusivity of the cloud <span class="hlt">lightning</span>, for the first time, are calculated by applying the transport theory of air plasma. In addition, we investigate the change behaviors of parameters (the temperature, the electron density, the electrical conductivity, the electron thermal conductivity, and the electron thermal diffusivity) in one of the cloud <span class="hlt">lightning</span> channels. The result shows that these parameters decrease slightly along developing direction of the cloud <span class="hlt">lightning</span> channel. Moreover, they represent similar suddenmore » change behavior in tortuous positions and the branch of the cloud <span class="hlt">lightning</span> channel.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EJPh...34..703W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EJPh...34..703W"><span>Study of the dynamic properties and effects of temperature using a spring model for the bouncing <span class="hlt">ball</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wadhwa, Ajay</p> <p>2013-05-01</p> <p>We studied the motion of a bouncing <span class="hlt">ball</span> by representing it through an equivalent mass-spring system executing damped harmonic oscillations. We represented the elasticity of the system through the spring constant ‘k’ and the viscous damping effect, causing loss of energy, through damping constant ‘c’. By including these two factors we formed a differential equation for the equivalent mass-spring system of the bouncing <span class="hlt">ball</span>. This equation was then solved to study the elastic and dynamic properties of its motion by expressing them in terms of experimentally measurable physical quantities such as contact time, coefficient of restitution, etc. We used our analysis for different types of <span class="hlt">ball</span> material: rubber (lawn-tennis <span class="hlt">ball</span>, super <span class="hlt">ball</span>, soccer <span class="hlt">ball</span> and squash <span class="hlt">ball</span>) and plastic (table-tennis <span class="hlt">ball</span>) at room temperature. Since the effect of temperature on the bounce of a squash <span class="hlt">ball</span> is significant, we studied the temperature dependence of its elastic properties. The experiments were performed using audio and surface-temperature sensors interfaced with a computer through a USB port. The work presented here is suitable for undergraduate <span class="hlt">laboratories</span>. It particularly emphasizes the use of computer interfacing for conducting conventional physics experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001AGUFMAE21A..06K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001AGUFMAE21A..06K"><span><span class="hlt">Lightning</span> Mapping Observations: What we are learning.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Krehbiel, P.</p> <p>2001-12-01</p> <p>The use of radio frequency time-of-arrival techniques for accurately mapping <span class="hlt">lightning</span> discharges is revolutionizing our ability to study <span class="hlt">lightning</span> discharge processes and to investigate thunderstorms. Different types of discharges are being observed that we have not been able to study before or knew existed. Included are a variety of inverted and normal polarity intracloud and cloud-to-ground discharges, frequent short-duration discharges at high altitude in storms and in overshooting convective tops, highly energetic impulsive discharge events, and horizontally extensive `spider' <span class="hlt">lightning</span> discharges in large mesoscale convective systems. High time resolution measurements valuably complement interferometric observations and are starting to exceed the ability of interferometers to provide detailed pictures of flash development. Mapping observations can be used to infer the polarity of the breakdown channels and hence the location and sign of charge regions in the storm. The <span class="hlt">lightning</span> activity in large, severe storms is found to be essentially continuous and volume-filling, with substantially more <span class="hlt">lightning</span> inside the storm than between the cloud and ground. Spectacular dendritic structures are observed in many flashes. The <span class="hlt">lightning</span> observations can be used to infer the electrical structure of a storm and therefore to study the electrification processes. The results are raising fundamental questions about how storms become electrified and how the electrification evolves with time. Supercell storms are commonly observed to electrify in an inverted or anomalous manner, raising questions about how these storms are different from normal storms, and even what is `normal'. The high <span class="hlt">lightning</span> rates in severe storms raises the distinct possibility that the discharges themselves might be sustaining or enhancing the electrification. Correlated observations with radar, instrumented balloons and aircraft, and ground-based measurements are leading to greatly improved</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title30-vol1/pdf/CFR-2012-title30-vol1-sec57-12065.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title30-vol1/pdf/CFR-2012-title30-vol1-sec57-12065.pdf"><span>30 CFR 57.12065 - Short circuit and <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-07-01</p> <p>... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Short circuit and <span class="hlt">lightning</span> protection. 57... MINES Electricity Surface Only § 57.12065 Short circuit and <span class="hlt">lightning</span> protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and <span class="hlt">lightning</span>. ...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title30-vol1/pdf/CFR-2014-title30-vol1-sec57-12065.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title30-vol1/pdf/CFR-2014-title30-vol1-sec57-12065.pdf"><span>30 CFR 57.12065 - Short circuit and <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-07-01</p> <p>... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Short circuit and <span class="hlt">lightning</span> protection. 57... MINES Electricity Surface Only § 57.12065 Short circuit and <span class="hlt">lightning</span> protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and <span class="hlt">lightning</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title30-vol1/pdf/CFR-2013-title30-vol1-sec57-12065.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title30-vol1/pdf/CFR-2013-title30-vol1-sec57-12065.pdf"><span>30 CFR 57.12065 - Short circuit and <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-07-01</p> <p>... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Short circuit and <span class="hlt">lightning</span> protection. 57... MINES Electricity Surface Only § 57.12065 Short circuit and <span class="hlt">lightning</span> protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and <span class="hlt">lightning</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title30-vol1/pdf/CFR-2011-title30-vol1-sec57-12065.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title30-vol1/pdf/CFR-2011-title30-vol1-sec57-12065.pdf"><span>30 CFR 57.12065 - Short circuit and <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-07-01</p> <p>... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Short circuit and <span class="hlt">lightning</span> protection. 57... MINES Electricity Surface Only § 57.12065 Short circuit and <span class="hlt">lightning</span> protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and <span class="hlt">lightning</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=338768&Lab=NERL&keyword=forensics&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=338768&Lab=NERL&keyword=forensics&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>A Performance Evaluation of <span class="hlt">Lightning</span>-NO Algorithms in CMAQ</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>In the Community Multiscale Air Quality (CMAQv5.2) model, we have implemented two algorithms for <span class="hlt">lightning</span> NO production; one algorithm is based on the hourly observed cloud-to-ground <span class="hlt">lightning</span> strike data from National <span class="hlt">Lightning</span> Detection Network (NLDN) to replace the previous m...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title30-vol1/pdf/CFR-2010-title30-vol1-sec57-12065.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title30-vol1/pdf/CFR-2010-title30-vol1-sec57-12065.pdf"><span>30 CFR 57.12065 - Short circuit and <span class="hlt">lightning</span> protection.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-07-01</p> <p>... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit and <span class="hlt">lightning</span> protection. 57... MINES Electricity Surface Only § 57.12065 Short circuit and <span class="hlt">lightning</span> protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and <span class="hlt">lightning</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100024155','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100024155"><span>Effects of <span class="hlt">Lightning</span> Injection on Power-MOSFETs</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Celaya, Jose; Saha, Sankalita; Wysocki, Phil; Ely, Jay; Nguyen, Truong; Szatkowski, George; Koppen, Sandra; Mielnik, John; Vaughan, Roger; Goebel, Kai</p> <p>2009-01-01</p> <p><span class="hlt">Lightning</span> induced damage is one of the major concerns in aircraft health monitoring. Such short-duration high voltages can cause significant damage to electronic devices. This paper presents a study on the effects of <span class="hlt">lightning</span> injection on power metal-oxide semiconductor field effect transistors (MOSFETs). This approach consisted of pin-injecting <span class="hlt">lightning</span> waveforms into the gate, drain and/or source of MOSFET devices while they were in the OFF-state. Analysis of the characteristic curves of the devices showed that for certain injection modes the devices can accumulate considerable damage rendering them inoperable. Early results demonstrate that a power MOSFET, even in its off-state, can incur considerable damage due to <span class="hlt">lightning</span> pin injection, leading to significant deviation in its behavior and performance, and to possibly early device failures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4332638','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4332638"><span>Factors Influencing <span class="hlt">Ball</span>-Player Impact Probability in Youth Baseball</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Matta, Philip A.; Myers, Joseph B.; Sawicki, Gregory S.</p> <p>2015-01-01</p> <p>Background: Altering the weight of baseballs for youth play has been studied out of concern for player safety. Research has shown that decreasing the weight of baseballs may limit the severity of both chronic arm and collision injuries. Unfortunately, reducing the weight of the <span class="hlt">ball</span> also increases its exit velocity, leaving pitchers and nonpitchers with less time to defend themselves. The purpose of this study was to examine impact probability for pitchers and nonpitchers. Hypothesis: Reducing the available time to respond by 10% (expected from reducing <span class="hlt">ball</span> weight from 142 g to 113 g) would increase impact probability for pitchers and nonpitchers, and players’ mean simple response time would be a primary predictor of impact probability for all participants. Study Design: Nineteen subjects between the ages of 9 and 13 years performed 3 experiments in a controlled <span class="hlt">laboratory</span> setting: a simple response time test, an avoidance response time test, and a pitching response time test. Methods: Each subject performed these tests in order. The simple reaction time test tested the subjects’ mean simple response time, the avoidance reaction time test tested the subjects’ ability to avoid a simulated batted <span class="hlt">ball</span> as a fielder, and the pitching reaction time test tested the subjects’ ability to avoid a simulated batted <span class="hlt">ball</span> as a pitcher. Results: Reducing the weight of a standard baseball from 142 g to 113 g led to a less than 5% increase in impact probability for nonpitchers. However, the results indicate that the impact probability for pitchers could increase by more than 25%. Conclusion: Pitching may greatly increase the amount of time needed to react and defend oneself from a batted <span class="hlt">ball</span>. Clinical Relevance: Impact injuries to youth baseball players may increase if a 113-g <span class="hlt">ball</span> is used. PMID:25984261</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150002157','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150002157"><span>Expanding the Operational Use of Total <span class="hlt">Lightning</span> Ahead of GOES-R</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stano, Geoffrey T.; Wood, Lance; Garner, Tim; Nunez, Roland; Kann, Deirdre; Reynolds, James; Rydell, Nezette; Cox, Rob; Bobb, William R.</p> <p>2015-01-01</p> <p>NASA's Short-term Prediction Research and Transition Center (SPoRT) has been transitioning real-time total <span class="hlt">lightning</span> observations from ground-based <span class="hlt">lightning</span> mapping arrays since 2003. This initial effort was with the local Weather Forecast Offices (WFO) that could use the North Alabama <span class="hlt">Lightning</span> Mapping Array (NALMA). These early collaborations established a strong interest in the use of total <span class="hlt">lightning</span> for WFO operations. In particular the focus started with warning decision support, but has since expanded to include impact-based decision support and <span class="hlt">lightning</span> safety. SPoRT has used its experience to establish connections with new <span class="hlt">lightning</span> mapping arrays as they become available. The GOES-R / JPSS Visiting Scientist Program has enabled SPoRT to conduct visits to new partners and expand the number of operational users with access to total <span class="hlt">lightning</span> observations. In early 2014, SPoRT conducted the most recent visiting scientist trips to meet with forecast offices that will used the Colorado, Houston, and Langmuir Lab (New Mexico) <span class="hlt">lightning</span> mapping arrays. In addition, SPoRT met with the corresponding Center Weather Service Units (CWSUs) to expand collaborations with the aviation community. These visits were an opportunity to learn about the forecast needs of each office visited as well as to provide on-site training for the use of total <span class="hlt">lightning</span>, setting the stage for a real-time assessment during May-July 2014. With five <span class="hlt">lightning</span> mapping arrays covering multiple geographic locations, the 2014 assessment has demonstrated numerous uses of total <span class="hlt">lightning</span> in varying situations. Several highlights include a much broader use of total <span class="hlt">lightning</span> for impact-based decision support ranging from airport weather warnings, supporting fire crews, and protecting large outdoor events. The inclusion of the CWSUs has broadened the operational scope of total <span class="hlt">lightning</span>, demonstrating how these data can support air traffic management, particularly in the Terminal Radar Approach</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29693567','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29693567"><span>Optical and Acoustic Sensor-Based 3D <span class="hlt">Ball</span> Motion Estimation for <span class="hlt">Ball</span> Sport Simulators †.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Seo, Sang-Woo; Kim, Myunggyu; Kim, Yejin</p> <p>2018-04-25</p> <p>Estimation of the motion of <span class="hlt">ball</span>-shaped objects is essential for the operation of <span class="hlt">ball</span> sport simulators. In this paper, we propose an estimation system for 3D <span class="hlt">ball</span> motion, including speed and angle of projection, by using acoustic vector and infrared (IR) scanning sensors. Our system is comprised of three steps to estimate a <span class="hlt">ball</span> motion: sound-based <span class="hlt">ball</span> firing detection, sound source localization, and IR scanning for motion analysis. First, an impulsive sound classification based on the mel-frequency cepstrum and feed-forward neural network is introduced to detect the <span class="hlt">ball</span> launch sound. An impulsive sound source localization using a 2D microelectromechanical system (MEMS) microphones and delay-and-sum beamforming is presented to estimate the firing position. The time and position of a <span class="hlt">ball</span> in 3D space is determined from a high-speed infrared scanning method. Our experimental results demonstrate that the estimation of <span class="hlt">ball</span> motion based on sound allows a wider activity area than similar camera-based methods. Thus, it can be practically applied to various simulations in sports such as soccer and baseball.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910046035&hterms=Gold+detector&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DGold%2Bdetector','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910046035&hterms=Gold+detector&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DGold%2Bdetector"><span>Ground Optical <span class="hlt">Lightning</span> Detector (GOLD)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jackson, John, Jr.; Simmons, David</p> <p>1990-01-01</p> <p>A photometer developed to characterize <span class="hlt">lightning</span> from the ground is discussed. The detector and the electronic signal processing and data storage systems are presented along with field data measured by the system. The discussion will include improvements that will be incorporated to enhance the measurement of <span class="hlt">lightning</span> and the data storage capability to record for many days without human involvement. Finally, the calibration of the GOLD system is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1511245D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1511245D"><span>Solar wind modulation of UK <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Davis, Chris; Harrison, Giles; Lockwood, Mike; Owens, Mathew; Barnard, Luke</p> <p>2013-04-01</p> <p>The response of <span class="hlt">lightning</span> rates in the UK to arrival of high speed solar wind streams at Earth is investigated using a superposed epoch analysis. The fast solar wind streams' arrivals are determined from modulation of the solar wind Vy component, measured by the Advanced Composition Explorer (ACE) spacecraft. <span class="hlt">Lightning</span> rate changes around these event times are then determined from the very low frequency Arrival Time Difference (ATD) system of the UK Met Office. Arrival of high speed streams at Earth is found to be preceded by a decrease in total solar irradiance and an increase in sunspot number and Mg II emissions. These are consistent with the high speed stream's source being co-located with an active region appearing on the Eastern solar limb and rotating at the 27 day rate of the Sun. Arrival of the high speed stream at Earth also coincides with a rapid decrease in cosmic ray flux and an increase in <span class="hlt">lightning</span> rates over the UK, persisting for around 40 days. The <span class="hlt">lightning</span> rate increase is corroborated by an increase in the total number of thunder days observed by UK Met stations, again for around 40 days after the arrival of a high speed solar wind stream. This increase in <span class="hlt">lightning</span> may be beneficial to medium range forecasting of hazardous weather.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19860003852','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19860003852"><span>Interpretation of F-106B in-flight <span class="hlt">lightning</span> signatures</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Trost, T. F.; Grothaus, M. G.; Wen, C. T.</p> <p>1985-01-01</p> <p>Various characteristics of the electromagnetic data obtained on a NASA F-106B aircraft during direct <span class="hlt">lightning</span> strikes are presented. Time scales of interest range from 10 ns to 400 microsecond. The following topics are discussed: (1) <span class="hlt">Lightning</span> current, I, measured directly versus I obtained from computer integration of measured I-dot; (2) A method of compensation for the low frequency cutoff of the current transformer used to measure I; (3) Properties of fast pulses observed in the <span class="hlt">lightning</span> time-derivative waveforms; (4) The characteristic D-dot signature of the F-106B aircraft; (5) An RC-discharge interpretation for some <span class="hlt">lightning</span> waveforms; (6) A method for inferring the locations of <span class="hlt">lightning</span> channel attachment points on the aircraft by using B-dot data; (7) Simple, approximate relationships between D-dot and I-dot and between B and I; and (8) Estimates of energy, charge, voltage, and resistance for a particular <span class="hlt">lightning</span> event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19345842','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19345842"><span>When <span class="hlt">lightning</span> strikes: bolting down the facts & fiction.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Usatch, Ben</p> <p>2009-04-01</p> <p>MYTH: There's no danger from <span class="hlt">lightning</span> until the rain starts. FACT: <span class="hlt">Lightning</span> often precedes the storm by up to 10 miles. A reasonable guideline is the "30-30 rule," by which you count the seconds between the flash and the thunder. If the time span is less than 30 seconds, seek shelter. Additionally, wait a full 30 minutes from last <span class="hlt">lightning</span> flash to resume outdoor activities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020068017&hterms=channels+distribution&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dchannels%2Bdistribution','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020068017&hterms=channels+distribution&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dchannels%2Bdistribution"><span>A <span class="hlt">Lightning</span> Channel Retrieval Algorithm for the North Alabama <span class="hlt">Lightning</span> Mapping Array (LMA)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William; Arnold, James E. (Technical Monitor)</p> <p>2002-01-01</p> <p>A new multi-station VHF time-of-arrival (TOA) antenna network is, at the time of this writing, coming on-line in Northern Alabama. The network, called the <span class="hlt">Lightning</span> Mapping Array (LMA), employs GPS timing and detects VHF radiation from discrete segments (effectively point emitters) that comprise the channel of <span class="hlt">lightning</span> strokes within cloud and ground flashes. The network will support on-going ground validation activities of the low Earth orbiting <span class="hlt">Lightning</span> Imaging Sensor (LIS) satellite developed at NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama. It will also provide for many interesting and detailed studies of the distribution and evolution of thunderstorms and <span class="hlt">lightning</span> in the Tennessee Valley, and will offer many interesting comparisons with other meteorological/geophysical wets associated with <span class="hlt">lightning</span> and thunderstorms. In order to take full advantage of these benefits, it is essential that the LMA channel mapping accuracy (in both space and time) be fully characterized and optimized. In this study, a new revised channel mapping retrieval algorithm is introduced. The algorithm is an extension of earlier work provided in Koshak and Solakiewicz (1996) in the analysis of the NASA Kennedy Space Center (KSC) <span class="hlt">Lightning</span> Detection and Ranging (LDAR) system. As in the 1996 study, direct algebraic solutions are obtained by inverting a simple linear system of equations, thereby making computer searches through a multi-dimensional parameter domain of a Chi-Squared function unnecessary. However, the new algorithm is developed completely in spherical Earth-centered coordinates (longitude, latitude, altitude), rather than in the (x, y, z) cartesian coordinates employed in the 1996 study. Hence, no mathematical transformations from (x, y, z) into spherical coordinates are required (such transformations involve more numerical error propagation, more computer program coding, and slightly more CPU computing time). The new algorithm also has a more realistic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=GL-2002-001565&hterms=eol&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Deol','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=GL-2002-001565&hterms=eol&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Deol"><span><span class="hlt">Lightning</span> over Equatorial Africa</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2002-01-01</p> <p>These two images were taken 9 seconds apart as the STS-97 Space Shuttle flew over equatorial Africa east of Lake Volta on December 11, 2000. The top of the large thunderstorm, roughly 20 km across, is illuminated by a full moon and frequent bursts of <span class="hlt">lightning</span>. Because the Space Shuttle travels at about 7 km/sec, the astronaut perspectives on this storm system becomes more oblique over the 9-second interval between photographs. The images were taken with a Nikon 35 mm camera equipped with a 400 mm lens and high-speed (800 ISO) color negative film. Images are STS097-351-9 and STS097-351-12, provided and archived by the Earth Science and Image Analysis <span class="hlt">Laboratory</span>, Johnson Space Center. Additional images taken by astronauts can be viewed at NASA-JSC's Gateway to Astronaut Photography of Earth at http://eol.jsc.nasa.gov/</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015676','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015676"><span>The GOES-R GeoStationary <span class="hlt">Lightning</span> Mapper (GLM)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodman, Steven J.; Blakeslee, Richard J.; Koshak, William J.; Mach, Douglas</p> <p>2011-01-01</p> <p>The Geostationary Operational Environmental Satellite (GOES-R) is the next series to follow the existing GOES system currently operating over the Western Hemisphere. Superior spacecraft and instrument technology will support expanded detection of environmental phenomena, resulting in more timely and accurate forecasts and warnings. Advancements over current GOES capabilities include a new capability for total <span class="hlt">lightning</span> detection (cloud and cloud-to-ground flashes) from the Geostationary <span class="hlt">Lightning</span> Mapper (GLM), and improved capability for the Advanced Baseline Imager (ABI). The Geostationary Lighting Mapper (GLM) will map total <span class="hlt">lightning</span> activity (in-cloud and cloud-to-ground lighting flashes) continuously day and night with near-uniform spatial resolution of 8 km with a product refresh rate of less than 20 sec over the Americas and adjacent oceanic regions. This will aid in forecasting severe storms and tornado activity, and convective weather impacts on aviation safety and efficiency among a number of potential applications. In parallel with the instrument development (a prototype and 4 flight models), a GOES-R Risk Reduction Team and Algorithm Working Group <span class="hlt">Lightning</span> Applications Team have begun to develop the Level 2 algorithms (environmental data records), cal/val performance monitoring tools, and new applications using GLM alone, in combination with the ABI, merged with ground-based sensors, and decision aids augmented by numerical weather prediction model forecasts. Proxy total <span class="hlt">lightning</span> data from the NASA <span class="hlt">Lightning</span> Imaging Sensor on the Tropical Rainfall Measuring Mission (TRMM) satellite and regional test beds are being used to develop the pre-launch algorithms and applications, and also improve our knowledge of thunderstorm initiation and evolution. An international field campaign planned for 2011-2012 will produce concurrent observations from a VHF <span class="hlt">lightning</span> mapping array, Meteosat multi-band imagery, Tropical Rainfall Measuring Mission (TRMM) <span class="hlt">Lightning</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMAE31B3416D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMAE31B3416D"><span>Analysis of ELF Radio Atmospherics Radiated by Rocket-Triggered <span class="hlt">Lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dupree, N. A.; Moore, R. C.; Pilkey, J. T.; Uman, M. A.; Jordan, D. M.; Caicedo, J. A.; Hare, B.; Ngin, T. K.</p> <p>2014-12-01</p> <p>Experimental observations of ELF radio atmospherics produced by rocket-triggered <span class="hlt">lightning</span> flashes are used to analyze Earth-ionosphere waveguide excitation and propagation characteristics. Rocket-triggered <span class="hlt">lightning</span> experiments are performed at the International Center for <span class="hlt">Lightning</span> Research and Testing (ICLRT) located at Camp Blanding, Florida. Long-distance ELF observations are performed in California, Greenland, and Antarctica. The <span class="hlt">lightning</span> current waveforms directly measured at the base of the <span class="hlt">lightning</span> channel (at the ICLRT) along with pertinent <span class="hlt">Lightning</span> Mapping Array (LMA) data are used together with the Long Wavelength Propagation Capability (LWPC) code to predict the radio atmospheric (sferic) waveform observed at the receiver locations under various ionospheric conditions. We identify fitted exponential electron density profiles that accurately describe the observed propagation delays, phase delays, and signal amplitudes. The ability to infer ionospheric characteristics using distant ELF observations greatly enhances ionospheric remote sensing capabilities, especially in regard to interpreting observations of transient luminous events (TLEs) and other ionospheric effects associated with <span class="hlt">lightning</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015774','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015774"><span>TRMM-Based <span class="hlt">Lightning</span> Climatology</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cecil, Daniel J.; Buechler, Dennis E.; Blakeslee, Richard J.</p> <p>2011-01-01</p> <p>Gridded climatologies of total <span class="hlt">lightning</span> flash rates seen by the spaceborne Optical Transient Detector (OTD) and <span class="hlt">Lightning</span> Imaging Sensor (LIS) have been updated. OTD collected data from May 1995 to March 2000. LIS data (equatorward of about 38 deg) has been added for 1998-2010. Flash counts from each instrument are scaled by the best available estimates of detection efficiency. The long LIS record makes the merged climatology most robust in the tropics and subtropics, while the high latitude data is entirely from OTD. The mean global flash rate from the merged climatology is 46 flashes per second. The peak annual flash rate at 0.5 deg scale is 160 fl/square km/yr in eastern Congo. The peak monthly average flash rate at 2.5 scale is 18 fl/square km/mo, from early April to early May in the Brahmaputra Valley of far eastern India. <span class="hlt">Lightning</span> decreases in this region during the monsoon season, but increases further north and west. A monthly average peak from early August to early September in northern Pakistan also exceeds any monthly averages from Africa, despite central Africa having the greatest yearly average. Most continental regions away from the equator have an annual cycle with <span class="hlt">lightning</span> flash rates peaking in late spring or summer. The main exceptions are India and southeast Asia, with springtime peaks in April and May. For landmasses near the equator, flash rates peak near the equinoxes. For many oceanic regions, the peak flash rates occur in autumn. This is particularly noticeable for the Mediterranean and North Atlantic. Landmasses have a strong diurnal cycle of <span class="hlt">lightning</span>, with flash rates generally peaking between 3-5 pm local solar time. The central United States flash rates peak later, in late evening or early night. Flash rates peak after midnight in northern Argentina. These regions are known for large, intense, long-lived mesoscale convective systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRD..118..787Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRD..118..787Z"><span>Statistical patterns in the location of natural <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zoghzoghy, F. G.; Cohen, M. B.; Said, R. K.; Inan, U. S.</p> <p>2013-01-01</p> <p><span class="hlt">Lightning</span> discharges are nature's way of neutralizing the electrical buildup in thunderclouds. Thus, if an individual discharge destroys a substantial fraction of the cloud charge, the probability of a subsequent flash is reduced until the cloud charge separation rebuilds. The temporal pattern of <span class="hlt">lightning</span> activity in a localized region may thus inherently be a proxy measure of the corresponding timescales for charge separation and electric field buildup processes. We present a statistical technique to bring out this effect (as well as the subsequent recovery) using <span class="hlt">lightning</span> geo-location data, in this case with data from the National <span class="hlt">Lightning</span> Detection Network (NLDN) and from the GLD360 Network. We use this statistical method to show that a <span class="hlt">lightning</span> flash can remove an appreciable fraction of the built up charge, affecting the neighboring <span class="hlt">lightning</span> activity for tens of seconds within a ˜ 10 km radius. We find that our results correlate with timescales of electric field buildup in storms and suggest that the proposed statistical tool could be used to study the electrification of storms on a global scale. We find that this flash suppression effect is a strong function of flash type, flash polarity, cloud-to-ground flash multiplicity, the geographic location of <span class="hlt">lightning</span>, and is proportional to NLDN model-derived peak stroke current. We characterize the spatial and temporal extent of the suppression effect as a function of these parameters and discuss various applications of our findings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20090017685&hterms=information+technology+trend&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dinformation%2Btechnology%2Btrend','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20090017685&hterms=information+technology+trend&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dinformation%2Btechnology%2Btrend"><span>An Operational Perspective of Total <span class="hlt">Lightning</span> Information</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Nadler, David J.; Darden, Christopher B.; Stano, Geoffrey; Buechler, Dennis E.</p> <p>2009-01-01</p> <p>The close and productive collaborations between the NWS Warning and Forecast Office, the Short Term Prediction and Research Transition Center at NASA Marshall Space Flight Center and the University of Alabama in Huntsville have provided a unique opportunity for science sharing and technology transfer. One significant technology transfer that has provided immediate benefits to NWS forecast and warning operations is the use of data from the North Alabama <span class="hlt">Lightning</span> Mapping Array. This network consists of ten VHF receivers deployed across northern Alabama and a base station located at the National Space Science and Technology Center. Preliminary investigations done at WFO Huntsville, along with other similar total <span class="hlt">lightning</span> networks across the country, have shown distinct correlations between the time rate-of-change of total <span class="hlt">lightning</span> and trends in intensity/severity of the parent convective cell. Since May 2003 when WFO HUN began receiving these data - in conjunction with other more traditional remotely sensed data (radar, satellite, and surface observations) -- have improved the situational awareness of the WFO staff. The use of total <span class="hlt">lightning</span> information, either from current ground based systems or future space borne instrumentation, may substantially contribute to the NWS mission, by enhancing severe weather warning and decision-making processes. Operational use of the data has been maximized at WFO Huntsville through a process that includes forecaster training, product implementation, and post event analysis and assessments. Since receiving these data, over 50 surveys have been completed highlighting the use of total <span class="hlt">lightning</span> information during significant events across the Tennessee Valley. In addition, around 150 specific cases of interest have been archived for collaborative post storm analysis. From these datasets, detailed trending information from radar and total <span class="hlt">lightning</span> can be compared to corresponding damage reports. This presentation will emphasize</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015499','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015499"><span>Aircraft <span class="hlt">Lightning</span> Electromagnetic Environment Measurement</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.</p> <p>2011-01-01</p> <p>This paper outlines a NASA project plan for demonstrating a prototype <span class="hlt">lightning</span> strike measurement system that is suitable for installation onto research aircraft that already operate in thunderstorms. This work builds upon past data from the NASA F106, FAA CV-580, and Transall C-180 flight projects, SAE ARP5412, and the European ILDAS Program. The primary focus is to capture airframe current waveforms during attachment, but may also consider pre and post-attachment current, electric field, and radiated field phenomena. New sensor technologies are being developed for this system, including a fiber-optic Faraday polarization sensor that measures <span class="hlt">lightning</span> current waveforms from DC to over several Megahertz, and has dynamic range covering hundreds-of-volts to tens-of-thousands-of-volts. A study of the electromagnetic emission spectrum of <span class="hlt">lightning</span> (including radio wave, microwave, optical, X-Rays and Gamma-Rays), and a compilation of aircraft transfer-function data (including composite aircraft) are included, to aid in the development of other new <span class="hlt">lightning</span> environment sensors, their placement on-board research aircraft, and triggering of the onboard instrumentation system. The instrumentation system will leverage recent advances in high-speed, high dynamic range, deep memory data acquisition equipment, and fiber-optic interconnect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120001434','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120001434"><span>The Goes-R Geostationary <span class="hlt">Lightning</span> Mapper (GLM)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodman, Steven J.; Blakeslee, Richard J.; Koshak, William J.; Mach, Douglas</p> <p>2011-01-01</p> <p>The Geostationary Operational Environmental Satellite (GOES-R) is the next series to follow the existing GOES system currently operating over the Western Hemisphere. Superior spacecraft and instrument technology will support expanded detection of environmental phenomena, resulting in more timely and accurate forecasts and warnings. Advancements over current GOES capabilities include a new capability for total <span class="hlt">lightning</span> detection (cloud and cloud-to-ground flashes) from the Geostationary <span class="hlt">Lightning</span> Mapper (GLM), and improved storm diagnostic capability with the Advanced Baseline Imager. The GLM will map total <span class="hlt">lightning</span> activity (in-cloud and cloud-to-ground lighting flashes) continuously day and night with near-uniform spatial resolution of 8 km with a product refresh rate of less than 20 sec over the Americas and adjacent oceanic regions. This will aid in forecasting severe storms and tornado activity, and convective weather impacts on aviation safety and efficiency. In parallel with the instrument development, a GOES-R Risk Reduction Team and Algorithm Working Group <span class="hlt">Lightning</span> Applications Team have begun to develop the Level 2 algorithms, cal/val performance monitoring tools, and new applications. Proxy total <span class="hlt">lightning</span> data from the NASA <span class="hlt">Lightning</span> Imaging Sensor on the Tropical Rainfall Measuring Mission (TRMM) satellite and regional test beds are being used to develop the pre-launch algorithms and applications, and also improve our knowledge of thunderstorm initiation and evolution. In this paper we will report on new Nowcasting and storm warning applications being developed and evaluated at various NOAA Testbeds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023322','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023322"><span>The Sandia transportable triggered <span class="hlt">lightning</span> instrumentation facility</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schnetzer, George H.; Fisher, Richard J.</p> <p>1991-01-01</p> <p>Development of the Sandia Transportable Triggered <span class="hlt">Lightning</span> Instrumentation Facility (SATTLIF) was motivated by a requirement for the in situ testing of a munitions storage bunker. Transfer functions relating the incident flash currents to voltages, currents, and electromagnetic field values throughout the structure will be obtained for use in refining and validating a <span class="hlt">lightning</span> response computer model of this type of structure. A preliminary shakedown trial of the facility under actual operational conditions was performed during summer of 1990 at the Kennedy Space Center's (KSC) rocket-triggered <span class="hlt">lightning</span> test site. A description is given of the SATTLIF, which is readily transportable on a single flatbed truck of by aircraft, and its instrumentation for measuring incident <span class="hlt">lightning</span> channel currents and the responses of the systems under test. Measurements of return-stroke current peaks obtained with the SATTLIF are presented. Agreement with data acquired on the same flashes with existing KSC instrumentation is, on average, to within approximately 7 percent. Continuing currents were measured with a resolution of approximately 2.5 A. This field trial demonstrated the practicality of using a transportable triggered <span class="hlt">lightning</span> facility for specialized test applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988STIA...8929272T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988STIA...8929272T"><span>Development of concepts for the protection of space launchers against <span class="hlt">lightning</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Taillet, Joseph</p> <p>1988-12-01</p> <p>Following a review of the characteristics of <span class="hlt">lightning</span> and the effects of <span class="hlt">lightning</span> on space launchers, various strategies for protection against <span class="hlt">lightning</span> are discussed. Special attention is given to the damage inflicted on the Apollo 12 and Atlas/Centaur vehicles by <span class="hlt">lightning</span>. It is demonstrated that the protection of space launchers is best performed by the real-time observation of atmospheric discharges at high altitude by such systems as the interferometric <span class="hlt">lightning</span> alert system, SAFIR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900037492&hterms=radioastronomy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dradioastronomy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900037492&hterms=radioastronomy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dradioastronomy"><span>Upper limit set for level of <span class="hlt">lightning</span> activity on Titan</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Desch, M. D.; Kaiser, M. L.</p> <p>1990-01-01</p> <p>Because optically thick cloud and haze layers prevent <span class="hlt">lightning</span> detection at optical wavelength on Titan, a search was conducted for <span class="hlt">lightning</span>-radiated signals (spherics) at radio wavelengths using the planetary radioastronomy instrument aboard Voyager 1. Given the maximum ionosphere density of about 3000/cu cm, <span class="hlt">lightning</span> spherics should be detectable above an observing frequency of 500 kHz. Since no evidence for spherics is found, an upper limit to the total energy per flash in Titan <span class="hlt">lightning</span> of about 10 to the 6th J, or about 1000 times weaker than that of typical terrestrial <span class="hlt">lightning</span>, is inferred.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PhTea..48..450C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PhTea..48..450C"><span>Enhancing the Bounce of a <span class="hlt">Ball</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cross, Rod</p> <p>2010-10-01</p> <p>In sports such as baseball, softball, golf, and tennis, a common objective is to hit the <span class="hlt">ball</span> as fast or as far as possible. Another common objective is to hit the <span class="hlt">ball</span> so that it spins as fast as possible, since the trajectory of the <span class="hlt">ball</span> through the air is strongly affected by <span class="hlt">ball</span> spin. In an attempt to enhance both the coefficient of restitution (COR) and the spin of a golf <span class="hlt">ball</span>, I conducted several experiments to see what would happen when a 45-g, 42.8-mm diameter golf <span class="hlt">ball</span> bounced on: (a) a 58-mm diameter, 103-g Super <span class="hlt">Ball</span>®; (b) an 8-mm thick, 56-mm diameter circular disk of Super <span class="hlt">Ball</span> material cut from a large Super <span class="hlt">Ball</span> and glued to a 3.4-kg lead brick; and (c) a 3-mm thick sheet of rubber glued to a 3.4-kg lead brick. (See Fig. 1.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17817848','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17817848"><span><span class="hlt">Lightning</span> on jupiter: rate, energetics, and effects.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lewis, J S</p> <p>1980-12-19</p> <p>Voyager data on the optical and radio-frequency detection of <span class="hlt">lightning</span> discharges in the atmosphere of Jupiter suggest a stroke rate significantly lower than on the earth. The efficiency of conversion of atmospheric convective energy flux into <span class="hlt">lightning</span> is almost certainly less than on the earth, probably near 10(-7) rather than the terrestrial value of 10(-4). At this level the rate of production of complex organic molecules by <span class="hlt">lightning</span> and by thunder shock waves is negligible compared to the rates of known photochemical processes for forming colored inorganic solids.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMAE11A..06M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMAE11A..06M"><span><span class="hlt">Lightning</span> Forecasts and Data Assimilation into Numerical Weather Prediction Models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>MacGorman, D. R.; Mansell, E. R.; Fierro, A.; Ziegler, C.</p> <p>2012-12-01</p> <p>This presentation reviews two aspects of <span class="hlt">lightning</span> in numerical weather prediction (NWP) models: forecasting <span class="hlt">lightning</span> and assimilating <span class="hlt">lightning</span> data into NWP models to improve weather forecasts. One of the earliest routine forecasts of <span class="hlt">lightning</span> was developed for fire weather operations. This approach used a multi-parameter regression analysis of archived cloud-to-ground (CG) <span class="hlt">lightning</span> data and archived NWP data to optimize the combination of model state variables to use in forecast equations for various CG rates. Since then, understanding of how storms produce <span class="hlt">lightning</span> has improved greatly. As the treatment of ice in microphysics packages used by NWP models has improved and the horizontal resolution of models has begun approaching convection-permitting scales (with convection-resolving scales on the horizon), it is becoming possible to use this improved understanding in NWP models to predict <span class="hlt">lightning</span> more directly. An important role for data assimilation in NWP models is to depict the location, timing, and spatial extent of thunderstorms during model spin-up so that the effects of prior convection that can strongly influence future thunderstorm activity, such as updrafts and outflow boundaries, can be included in the initial state of a NWP model run. Radar data have traditionally been used, but systems that map <span class="hlt">lightning</span> activity with varying degrees of coverage, detail, and detection efficiency are now available routinely over large regions and reveal information about storms that is complementary to the information provided by radar. Because data from <span class="hlt">lightning</span> mapping systems are compact, easily handled, and reliably indicate the location and timing of thunderstorms, even in regions with little or no radar coverage, several groups have investigated techniques for assimilating these data into NWP models. This application will become even more valuable with the launch of the Geostationary <span class="hlt">Lightning</span> Mapper on the GOES-R satellite, which will extend routine</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840019308','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840019308"><span>Data and results of a <span class="hlt">laboratory</span> investigation of microprocessor upset caused by simulated <span class="hlt">lightning</span>-induced analog transients</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Belcastro, C. M.</p> <p>1984-01-01</p> <p>A methodology was developed a assess the upset susceptibility/reliability of a computer system onboard an aircraft flying through a <span class="hlt">lightning</span> environment. Upset error modes in a general purpose microprocessor were studied. The upset tests involved the random input of analog transients which model <span class="hlt">lightning</span> induced signals onto interface lines of an 8080 based microcomputer from which upset error data was recorded. The program code on the microprocessor during tests is designed to exercise all of the machine cycles and memory addressing techniques implemented in the 8080 central processing unit. A statistical analysis is presented in which possible correlations are established between the probability of upset occurrence and transient signal inputs during specific processing states and operations. A stochastic upset susceptibility model for the 8080 microprocessor is presented. The susceptibility of this microprocessor to upset, once analog transients have entered the system, is determined analytically by calculating the state probabilities of the stochastic model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015649','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015649"><span>The NASA <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM): Application to Air Quality Modeling</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William; Peterson, Harold; Khan, Maudood; Biazar, Arastoo; Wang, Lihua</p> <p>2011-01-01</p> <p>Recent improvements to the NASA Marshall Space Flight Center <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) and its application to the Community Multiscale Air Quality (CMAQ) modeling system are discussed. The LNOM analyzes <span class="hlt">Lightning</span> Mapping Array (LMA) and National <span class="hlt">Lightning</span> Detection Network(TradeMark)(NLDN) data to estimate the raw (i.e., unmixed and otherwise environmentally unmodified) vertical profile of <span class="hlt">lightning</span> NO(x) (= NO + NO2). The latest LNOM estimates of <span class="hlt">lightning</span> channel length distributions, <span class="hlt">lightning</span> 1-m segment altitude distributions, and the vertical profile of <span class="hlt">lightning</span> NO(x) are presented. The primary improvement to the LNOM is the inclusion of non-return stroke <span class="hlt">lightning</span> NOx production due to: (1) hot core stepped and dart leaders, (2) stepped leader corona sheath, K-changes, continuing currents, and M-components. The impact of including LNOM-estimates of <span class="hlt">lightning</span> NO(x) for an August 2006 run of CMAQ is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012IJTPE.132..102S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012IJTPE.132..102S"><span>Seasonal and Local Characteristics of <span class="hlt">Lightning</span> Outages of Power Distribution Lines in Hokuriku Area</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sugimoto, Hitoshi; Shimasaki, Katsuhiko</p> <p></p> <p>The proportion of the <span class="hlt">lightning</span> outages in all outages on Japanese 6.6kV distribution lines is high with approximately 20 percent, and then <span class="hlt">lightning</span> protections are very important for supply reliability of 6.6kV lines. It is effective for the <span class="hlt">lightning</span> performance to apply countermeasures in order of the area where a large number of the <span class="hlt">lightning</span> outages occur. Winter <span class="hlt">lightning</span> occurs in Hokuriku area, therefore it is also important to understand the seasonal characteristics of the <span class="hlt">lightning</span> outages. In summer 70 percent of the <span class="hlt">lightning</span> outages on distribution lines in Hokuriku area were due to sparkover, such as power wire breakings and failures of pole-mounted transformers. However, in winter almost half of <span class="hlt">lightning</span>-damaged equipments were surge arrester failures. The number of the <span class="hlt">lightning</span> outages per <span class="hlt">lightning</span> strokes detected by the <span class="hlt">lightning</span> location system (LLS) in winter was 4.4 times larger than that in summer. The authors have presumed the occurrence of <span class="hlt">lightning</span> outages from <span class="hlt">lightning</span> stroke density, 50% value of <span class="hlt">lightning</span> current and installation rate of <span class="hlt">lightning</span> protection equipments and overhead ground wire by multiple regression analysis. The presumed results suggest the local difference in the <span class="hlt">lightning</span> outages.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMAE13A0330L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMAE13A0330L"><span>Dual-Polarization Radar Observations of Upward <span class="hlt">Lightning</span>-Producing Storms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lueck, R.; Helsdon, J. H.; Warner, T.</p> <p>2013-12-01</p> <p>The Upward <span class="hlt">Lightning</span> Triggering Study (UPLIGHTS) seeks to determine how upward <span class="hlt">lightning</span>, which originates from the tips of tall objects, is triggered by nearby flash activity. As a component of this study we analyze standard and dual-polarization weather radar data. The Correlation Coefficient (CC) in particular can be used to identify and quantify the melting layer associated with storms that produce upward <span class="hlt">lightning</span>. It has been proposed that positive charge generation due to aggregate shedding at the melting layer results in a positive charge region just above the cloud base. This positive charge region may serve as a positive potential well favorable for negative leader propagation, which initiate upward positive leaders from tall objects. We characterize the horizontal coverage, thickness and height of the melting layer in addition to cloud base heights when upward <span class="hlt">lightning</span> occurs to determine trends and possible threshold criteria relating to upward <span class="hlt">lightning</span> production. Furthermore, we characterize storm type and morphology using relevant schemes as well as precipitation type using the Hydrometer Classification Algorithm (HCA) for upward <span class="hlt">lightning</span>-producing storms. Ice-phase hydrometeors have been shown to be a significant factor in thunderstorm electrification. Only a small fraction of storms produce upward <span class="hlt">lightning</span>, so null cases will be examined and compared as well.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29527425','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29527425"><span>The Evolution and Structure of Extreme Optical <span class="hlt">Lightning</span> Flashes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Peterson, Michael; Rudlosky, Scott; Deierling, Wiebke</p> <p>2017-12-27</p> <p>This study documents the composition, morphology, and motion of extreme optical <span class="hlt">lightning</span> flashes observed by the <span class="hlt">Lightning</span> Imaging Sensor (LIS). The furthest separation of LIS events (groups) in any flash is 135 km (89 km), the flash with the largest footprint had an illuminated area of 10,604 km 2 , and the most dendritic flash has 234 visible branches. The longest-duration convective LIS flash lasted 28 s and is overgrouped and not physical. The longest-duration convective-to-stratiform propagating flash lasted 7.4 s, while the longest-duration entirely stratiform flash lasted 4.3 s. The longest series of nearly consecutive groups in time lasted 242 ms. The most radiant recorded LIS group (i.e., "superbolt") is 735 times more radiant than the average group. Factors that impact these optical measures of flash morphology and evolution are discussed. While it is apparent that LIS can record the horizontal development of the <span class="hlt">lightning</span> channel in some cases, radiative transfer within the cloud limits the flash extent and level of detail measured from orbit. These analyses nonetheless suggest that <span class="hlt">lightning</span> imagers such as LIS and Geostationary <span class="hlt">Lightning</span> Mapper can complement ground-based <span class="hlt">lightning</span> locating systems for studying physical <span class="hlt">lightning</span> phenomena across large geospatial domains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5843378','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5843378"><span>The Evolution and Structure of Extreme Optical <span class="hlt">Lightning</span> Flashes</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Peterson, Michael; Rudlosky, Scott; Deierling, Wiebke</p> <p>2018-01-01</p> <p>This study documents the composition, morphology, and motion of extreme optical <span class="hlt">lightning</span> flashes observed by the <span class="hlt">Lightning</span> Imaging Sensor (LIS). The furthest separation of LIS events (groups) in any flash is 135 km (89 km), the flash with the largest footprint had an illuminated area of 10,604 km2, and the most dendritic flash has 234 visible branches. The longest-duration convective LIS flash lasted 28 s and is overgrouped and not physical. The longest-duration convective-to-stratiform propagating flash lasted 7.4 s, while the longest-duration entirely stratiform flash lasted 4.3 s. The longest series of nearly consecutive groups in time lasted 242 ms. The most radiant recorded LIS group (i.e., “superbolt”) is 735 times more radiant than the average group. Factors that impact these optical measures of flash morphology and evolution are discussed. While it is apparent that LIS can record the horizontal development of the <span class="hlt">lightning</span> channel in some cases, radiative transfer within the cloud limits the flash extent and level of detail measured from orbit. These analyses nonetheless suggest that <span class="hlt">lightning</span> imagers such as LIS and Geostationary <span class="hlt">Lightning</span> Mapper can complement ground-based <span class="hlt">lightning</span> locating systems for studying physical <span class="hlt">lightning</span> phenomena across large geospatial domains. PMID:29527425</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=sky&pg=6&id=EJ1128438','ERIC'); return false;" href="https://eric.ed.gov/?q=sky&pg=6&id=EJ1128438"><span>When <span class="hlt">Lightning</span> Strikes a Second Time</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Allen, Kent</p> <p>2017-01-01</p> <p>The chances of <span class="hlt">lightning</span> striking twice are infinitesimal, at best. What are the odds, in middle age, of being struck with a jarring bolt of figurative <span class="hlt">lightning</span>, then a few months later being an eyewitness as the same sizzle in the sky jolts a group of students--those decision-makers of tomorrow? The author describes two experiences that proved…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002EGSGA..27.2157K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002EGSGA..27.2157K"><span>Gravito-electrodynamics, Ehd and Their Applications To Natural Hazards and <span class="hlt">Laboratory</span> Devices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kikuchi, H.</p> <p></p> <p>For the past two decades, theory of dusty and dirty plasmas in space and in the labo - ratory has been developed on the basis of both unconventional gravito-electrody- nam ics and a new EHD (electrohydrodynamics) with novel concepts of electric re- connection and critical ionization velocity as well as modern concepts of self-organ- ization and chaos and has been applied to explanations of a variety of new dust-re- lated and meteorologyico-electric phenomena such as planetary (Saturn's and Jupi- ter's) dust layer or ring formation, terrestrial dust layer formation, terrestrial light - ning including winter thunderstorms, rocket and tower triggered <span class="hlt">lightning</span>, planetary (Saturn's, Jupiter's, and Io's) <span class="hlt">lightning</span>, nebular <span class="hlt">lightning</span>, <span class="hlt">ball</span> <span class="hlt">lightning</span>, tornadic thunderstorms, whirlwinds, cloud-to-ionosphere discharges, pre-earthquake atmo- sphereic and ionospheric effects, and new <span class="hlt">laboratory</span> devices such as electric undu - lators, a universal electric-cusp type plasma reactor for basic <span class="hlt">laboratory</span> studies, sim- ulations of atmospheric phenomena and pollution control and gas cleaning, plasma processing and new material production for industrial applications, and new devices such as towards cancer treatment for biological and medical applications. Reference H. Kikuchi, Electrohydrodynamics in Dusty and Dirty plasmas, Kluwer Academic Publishers, Dordrecht/The Netherlands, 2001. For describing any plasmas, particle dynamics plays always fundamental and impor - tant roles in understanding all of plasma behaviors. A variety of descriptions in a magnetic field such as a guiding center approach have well been developed as a test-particle approach particularly for a base of MHD. This is still true for EHD or EMHD, but additional factors become significant due to the existence of space charges and electric fields for EHD or EMHD in dielectric or semiconducting fluids. In cosmic plasmas, the existence of double layers, electric and magnetic dipoles or quadru-poles often affects the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014R%26QE...56..839S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014R%26QE...56..839S"><span>A Study of Parameters of the Counterpropagating Leader and its Influence on the <span class="hlt">Lightning</span> Protection of Objects Using Large-Scale <span class="hlt">Laboratory</span> Modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Syssoev, V. S.; Kostinskiy, A. Yu.; Makalskiy, L. M.; Rakov, A. V.; Andreev, M. G.; Bulatov, M. U.; Sukharevsky, D. I.; Naumova, M. U.</p> <p>2014-04-01</p> <p>In this work, the results of experiments on initiating the upward and descending leaders during the development of a long spark when studying <span class="hlt">lightning</span> protection of objects with the help of large-scale models are shown. The influence of the counterpropagating leaders on the process of the <span class="hlt">lightning</span> strike of ground-based and insulated objects is discussed. In the first case, the upward negative leader is initiated by the positive downward leader, which propagates from the high-voltage electrode of the "rod-rod"-type Marx generator (the rod is located on the plane and is 3-m high) in the gap with a length of 9-12 m. The positive-voltage pulse with a duration of 7500 μs had an amplitude of up to 3 MV. In the second case, initiation of the positive upward leader was performed in the electric field created by a cloud of negatively charged aerosol, which simulates the charged thunderstorm cell. In this case, all the phases characteristic of the ascending <span class="hlt">lightnings</span> initiated by the tall ground-based objects and the triggered <span class="hlt">lightnings</span> during the experiments with an actual thunderstorm cloud were observed in the forming spark discharge with a length of 1.5-2.0 m. The main parameters of the counterpropagating leader, which is initiated by the objects during the large-scale model experiments with a long spark, are shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=bats&id=EJ1049058','ERIC'); return false;" href="https://eric.ed.gov/?q=bats&id=EJ1049058"><span><span class="hlt">Ball</span> Collision Experiments</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Cross, R.</p> <p>2015-01-01</p> <p>Experiments are described on collisions between two billiard <span class="hlt">balls</span> and between a bat and a <span class="hlt">ball</span>. The experiments are designed to extend a student's understanding of collision events and could be used either as a classroom demonstration or for a student project.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20090025955&hterms=cloud+cost+effective&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcloud%2Bcost%2Beffective%26Nf%3DPublication-Date%257CBTWN%2B20080101%2B20180619','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20090025955&hterms=cloud+cost+effective&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcloud%2Bcost%2Beffective%26Nf%3DPublication-Date%257CBTWN%2B20080101%2B20180619"><span>Forecasting <span class="hlt">Lightning</span> Threat using Cloud-resolving Model Simulations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>McCaul, E. W., Jr.; Goodman, S. J.; LaCasse, K. M.; Cecil, D. J.</p> <p>2009-01-01</p> <p>As numerical forecasts capable of resolving individual convective clouds become more common, it is of interest to see if quantitative forecasts of <span class="hlt">lightning</span> flash rate density are possible, based on fields computed by the numerical model. Previous observational research has shown robust relationships between observed <span class="hlt">lightning</span> flash rates and inferred updraft and large precipitation ice fields in the mixed phase regions of storms, and that these relationships might allow simulated fields to serve as proxies for <span class="hlt">lightning</span> flash rate density. It is shown in this paper that two simple proxy fields do indeed provide reasonable and cost-effective bases for creating time-evolving maps of predicted <span class="hlt">lightning</span> flash rate density, judging from a series of diverse simulation case study events in North Alabama for which <span class="hlt">Lightning</span> Mapping Array data provide ground truth. One method is based on the product of upward velocity and the mixing ratio of precipitating ice hydrometeors, modeled as graupel only, in the mixed phase region of storms at the -15\\dgc\\ level, while the second method is based on the vertically integrated amounts of ice hydrometeors in each model grid column. Each method can be calibrated by comparing domainwide statistics of the peak values of simulated flash rate proxy fields against domainwide peak total <span class="hlt">lightning</span> flash rate density data from observations. Tests show that the first method is able to capture much of the temporal variability of the <span class="hlt">lightning</span> threat, while the second method does a better job of depicting the areal coverage of the threat. A blended solution is designed to retain most of the temporal sensitivity of the first method, while adding the improved spatial coverage of the second. Weather Research and Forecast Model simulations of selected North Alabama cases show that this model can distinguish the general character and intensity of most convective events, and that the proposed methods show promise as a means of generating</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140013298','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140013298"><span>Three Dimensional <span class="hlt">Lightning</span> Launch Commit Criteria Visualization Tool</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bauman, William H., III</p> <p>2014-01-01</p> <p><span class="hlt">Lightning</span> occurrence too close to a NASA LSP or future SLS program launch vehicle in flight would have disastrous results. The sensitive electronics on the vehicle could be damaged to the point of causing an anomalous flight path and ultimate destruction of the vehicle and payload.According to 45th Weather Squadron (45 WS) <span class="hlt">Lightning</span> Launch Commit Criteria (LLCC), a vehicle cannot launch if <span class="hlt">lightning</span> is within 10 NM of its pre-determined flight path. The 45 WS Launch Weather Officers (LWOs) evaluate this LLCC for their launch customers to ensure the safety of the vehicle in flight. Currently, the LWOs conduct a subjective analysis of the distance between <span class="hlt">lightning</span> and the flight path using data from different display systems. A 3-D display in which the <span class="hlt">lightning</span> data and flight path are together would greatly reduce the ambiguity in evaluating this LLCC. It would give the LWOs and launch directors more confidence in whether a GO or NO GO for launch should be issued. When <span class="hlt">lightning</span> appears close to the path, the LWOs likely err on the side of conservatism and deem the <span class="hlt">lightning</span> to be within 10 NM. This would cause a costly delay or scrub. If the LWOs can determine with a strong level of certainty that the <span class="hlt">lightning</span> is beyond 10 NM, launch availability would increase without compromising safety of the vehicle, payload or, in the future, astronauts.The AMU was tasked to conduct a market research of commercial, government, and open source software that might be able to ingest and display the 3-D <span class="hlt">lightning</span> data from the KSC <span class="hlt">Lightning</span> Mapping Array (LMA), the 45th Space Wing Weather Surveillance Radar (WSR), the National Weather Service in Melbourne Weather Surveillance Radar 1988 Doppler (WSR-88D), and the vehicle flight path data so that all can be visualized together. To accomplish this, the AMU conducted Internet searches for potential software candidates and interviewed software developers.None of the available off-the-shelf software had a 3-D capability that could</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <div class="footer-extlink text-muted" style="margin-bottom:1rem; text-align:center;">Some links on this page may take you to non-federal websites. 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