Sample records for lightning test program

  1. High current lightning test of space shuttle external tank lightning protection system

    NASA Technical Reports Server (NTRS)

    Mumme, E.; Anderson, A.; Schulte, E. H.

    1977-01-01

    During lift-off, the shuttle launch vehicle (external tank, solid rocket booster and orbiter) may be subjected to a lightning strike. Tests of a proposed lightning protection method for the external tank and development materials which were subjected to simulated lightning strikes are described. Results show that certain of the high resistant paint strips performed remarkably well in diverting the 50 kA lightning strikes.

  2. 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.

  3. Lightning testing at the subsystem level

    NASA Technical Reports Server (NTRS)

    Luteran, Frank

    1991-01-01

    Testing at the subsystem or black box level for lightning 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 lightning stimulation. Equipment for testing at this level should be portable or at least movable to enable efficient testing in a design laboratory 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 lightning 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 lightning stimulation parameters in order to build practical test equipment. Peak power levels that can be generated at specified bandwidths with

  4. Lightning Pin Injection Testing on MOSFETS

    NASA Technical Reports Server (NTRS)

    Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.; Koppen, Sandra V.; Mielnik, John J.; Vaughan, Roger K.; Wysocki, Philip F.; Celaya, Jose R.; Saha, Sankalita

    2009-01-01

    Lightning transients were pin-injected into metal-oxide-semiconductor field-effect transistors (MOSFETs) to induce fault modes. This report documents the test process and results, and provides a basis for subsequent lightning tests. MOSFETs may be present in DC-DC power supplies and electromechanical actuator circuits that may be used on board aircraft. Results show that unprotected MOSFET Gates are susceptible to failure, even when installed in systems in well-shielded and partial-shielded locations. MOSFET Drains and Sources are significantly less susceptible. Device impedance decreased (current increased) after every failure. Such a failure mode may lead to cascading failures, as the damaged MOSFET may allow excessive current to flow through other circuitry. Preliminary assessments on a MOSFET subjected to 20-stroke pin-injection testing demonstrate that Breakdown Voltage, Leakage Current and Threshold Voltage characteristics show damage, while the device continues to meet manufacturer performance specifications. The purpose of this research is to develop validated tools, technologies, and techniques for automated detection, diagnosis and prognosis that enable mitigation of adverse events during flight, such as from lightning transients; and to understand the interplay between lightning-induced surges and aging (i.e. humidity, vibration thermal stress, etc.) on component degradation.

  5. An Approach to the Lightning Overvoltage Protection of Medium Voltage Lines in Severe Lightning Areas

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

    Omidiora, M. A.; Lehtonen, M.

    2008-05-08

    This paper deals with the effect of shield wires on lightning 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 lightning protection in Finnish distribution networks where lightning is most severe. The true index of lightning 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 lightning strokes and simulated with the Alternative Transients Program/Electromagnetic Transients program (ATP/EMTP). Themore » response of the distribution line to lightning 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

  6. Space Shuttle Lightning Protection

    NASA Technical Reports Server (NTRS)

    Suiter, D. L.; Gadbois, R. D.; Blount, R. L.

    1979-01-01

    The technology for lightning 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 Lightning Protection Program is discussed, including the general types of protection, testing, and anlayses being performed to assess the lightning-transient-damage susceptibility of solid-state electronics.

  7. Follow-on cable coupling lightning test, volume 1

    NASA Technical Reports Server (NTRS)

    Danforth, Richard

    1990-01-01

    A redesigned solid rocket motor test article was subjected to simulated lightning strikes. This test was performed to evaluate the effects of lightning strike to the redesigned motor and Space Transportation System. The purpose of the test was to evaluate the performance of systems tunnel design changes when subjected to the lightning discharges. The goal of the design changes was to reduce lightning induced coupling to cables within the systems tunnel. The test article was subjected to several different amounts and kinds of discharges. Changes in coupling levels detected during the tests are recorded. The dominant mode of coupling appears to be caused by the diffusion of the magnetic fields through the system tunnel covers. The results from bond strap integrity testing showed that 16 of 18 bond straps survived. Design change evaluations showed that coupling reduction ranged from 0 to 36 decibels for each type of cable. The type of cable has less effect on coupling than does strike location and strike levels. Recommendations for design changes are made.

  8. A simulated lightning effects test facility for testing live and inert missiles and components

    NASA Technical Reports Server (NTRS)

    Craven, Jeffery D.; Knaur, James A.; Moore, Truman W., Jr.; Shumpert, Thomas H.

    1991-01-01

    Details of a simulated lightning effects test facility for testing live and inert missiles, motors, and explosive components are described. The test facility is designed to simulate the high current, continuing current, and high rate-of-rise current components of an idealized direct strike lightning waveform. The Lightning Test Facility was in operation since May, 1988, and consists of: 3 separate capacitor banks used to produce the lightning test components; a permanently fixed large steel safety cage for retaining the item under test (should it be ignited during testing); an earth covered bunker housing the control/equipment room; a charge/discharge building containing the charging/discharging switching; a remotely located blockhouse from which the test personnel control hazardous testing; and interconnecting cables.

  9. Lightning NOx Estimates from Space-Based Lightning Imagers

    NASA Technical Reports Server (NTRS)

    Koshak, William J.

    2017-01-01

    The intense heating of air by a lightning channel, and subsequent rapid cooling, leads to the production of lightning nitrogen oxides (NOx = NO + NO2) as discussed in Chameides [1979]. In turn, the lightning 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, lightning 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 lightning-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 lightning observations as they pertain to changes in climate. In particular, changes in lightning characteristics over the conterminous US (CONUS) continue to be examined by this author using data from the Tropical Rainfall Measuring Mission Lightning Imaging Sensor. In this study, preliminary estimates of LNOx trends derived from TRMM/LIS lightning 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

  10. Test Report: Direct and Indirect Lightning Effects on Composite Materials

    NASA Technical Reports Server (NTRS)

    Evans, R. W.

    1997-01-01

    Lightning tests were performed on composite materials as a part of an investigation of electromagnetic effects on the materials. Samples were subjected to direct and remote simulated lightning strikes. Samples included various thicknesses of graphite filament reinforced plastic (GFRP), material enhanced by expanded aluminum foil layers, and material with an aluminum honeycomb core. Shielding properties of the material and damage to the sample surfaces and joints were investigated. Adding expanded aluminum foil layers and increasing the thickness of GFRP improves the shielding effectiveness against lightning induced fields and the ability to withstand lightning strikes. A report describing the lightning strike tests performed by the U.S. Army Redstone Technical Test Center, Redstone Arsenal, AL, STERT-TE-E-EM, is included as an appendix.

  11. Lightning Pin Injection Test: MOSFETS in "ON" State

    NASA Technical Reports Server (NTRS)

    Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.; Koppen, Sandra V.; Mielnik, John J.; Vaughan, Roger K.; Saha, Sankalita; Wysocki, Philip F.; Celaya, Jose R.

    2011-01-01

    The test objective was to evaluate MOSFETs for induced fault modes caused by pin-injecting a standard lightning waveform into them while operating. Lightning Pin-Injection testing was performed at NASA LaRC. Subsequent fault-mode and aging studies were performed by NASA ARC researchers using the Aging and Characterization Platform for semiconductor components. This report documents the test process and results, to provide a basis for subsequent lightning tests. The ultimate IVHM goal is to apply prognostic and health management algorithms using the features extracted during aging to allow calculation of expected remaining useful life. A survey of damage assessment techniques based upon inspection is provided, and includes data for optical microscope and X-ray inspection. Preliminary damage assessments based upon electrical parameters are also provided.

  12. Lightning protection guidelines and test data for adhesively bonded aircraft structures

    NASA Technical Reports Server (NTRS)

    Pryzby, J. E.; Plumer, J. A.

    1984-01-01

    The highly competitive marketplace and increasing cost of energy has motivated manufacturers of general aviation aircraft to utilize composite materials and metal-to-metal bonding in place of conventional fasteners and rivets to reduce weight, obtain smoother outside surfaces and reduce drag. The purpose of this program is protection of these new structures from hazardous lightning effects. The program began with a survey of advance-technology materials and fabrication methods under consideration for future designs. Sub-element specimens were subjected to simulated lightning voltages and currents. Measurements of bond line voltages, electrical sparking, and mechanical strength degradation were made to comprise a data base of electrical properties for new technology materials and basic structural configurations. The second hase of the program involved tests on full scale wing structures which contained integral fuel tanks and which were representative of examples of new technology structures and fuel systems. The purpose of these tests was to provide a comparison between full scale structural measurements and those obtained from the sub-element specimens.

  13. Lightning protection design and testing of an all composite wet wing for the Egrett

    NASA Technical Reports Server (NTRS)

    Burrows, B. J. C.; Haigh, S. J.; Chessum, C.; Dunkley, V. P.

    1991-01-01

    The Egrett aircraft has an all composite wing comprising CFC(carbon fiber composite)/Nomex sandwich skins, full length CFC main spar caps, and GFRP (glass fiber reinforced plastics) main and auxiliary spar webs. It also has short inboard CFC auxiliary spar caps. It has fine aluminum wires woven into the surface for protection. It has an integral fuel tank using the CFC/Nomex skins as the upper and lower tank walls, and lies between the forward auxiliary spar and the forward of the two main spar webs. The fuel tank is not bagged, i.e., it is in effect a wet wing tank. It has conventional capacitive type fuel gauging. The aircraft was cleared to IFR standards and so required full lightning protection and demonstration that it would survive the lightning environment. The lightning protection was designed for the wing (and also for the remainder of the aircraft). An inner wing test samples (which included a part of the fuel tank) were tested as part of the proving program. The protection design and the testing process are described. The intrinsic structural features are indicated that improve lightning protection design and which therefore minimize the weight and cost of any added lightning protection components.

  14. Assessment of the Pseudo Geostationary Lightning Mapper Products at the Spring Program and Summer Experiment

    NASA Technical Reports Server (NTRS)

    Stano, Geoffrey T.; Calhoun, Kristin K.; Terborg, Amanda M.

    2014-01-01

    Since 2010, the de facto Geostationary Lightning Mapper (GLM) demonstration product has been the Pseudo-Geostationary Lightning Mapper (PGLM) product suite. Originally prepared for the Hazardous Weather Testbed's Spring Program (specifically the Experimental Warning Program) when only four ground-based lightning 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 Laboratory 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 Laboratory's total lightning 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 lightning 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

  15. F-5F Shark Nose radome lightning test

    NASA Technical Reports Server (NTRS)

    Scott, G. W.

    1980-01-01

    A unique F-5F radome wtih a geometry similar to a Shark Nose profile was tested with a high voltage Marx generator, 1,200,000 volts in order to demonstrate the effectiveness of the lightning protection system with currents from 5,000 amperes or greater. An edge discontinuity configuration is a characteristic feature in the forward region of the radome and occasionally serves as an attachment point. The results of nineteen attachment tests at various aspect angles with an air gap of one meter indicated that no damage occurred to the dielectric material of the radom. The test proved the effectiveness of the lightning protection system.

  16. Lightning Tracking Tool for Assessment of Total Cloud Lightning within AWIPS II

    NASA Technical Reports Server (NTRS)

    Burks, Jason E.; Stano, Geoffrey T.; Sperow, Ken

    2014-01-01

    Total lightning (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 lightning has been related to the strength of a storm's updraft. Therefore a rapid increase in total lightning 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 lightning. A tool has been developed at NASA's Short-term Prediction Research and Transition (SPoRT) Center to assist in quickly analyzing the total lightning 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 lightning. This tool also takes advantage of the new architecture available within the AWIPS II environment. SPoRT's lightning 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 lightning 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 lightning jump algorithm.

  17. Lightning protection technology for small general aviation composite material aircraft

    NASA Technical Reports Server (NTRS)

    Plumer, J. A.; Setzer, T. E.; Siddiqi, S.

    1993-01-01

    An on going NASA (Small Business Innovative Research) SBIR Phase II design and development program will produce the first lightning 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 lightning protection design methodology and materials chosen are capable of protecting such small composite airframes from lightning puncture and structural damage associated with severe threat lightning 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 laboratory testing, thus enabling production and sale of owner-built, lightning-protected, Stoddard-Hamilton Aircraft, Inc. Glasair II airplanes. A second objective has been to provide lightning 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.

  18. The High Energy Lightning Simulator (HELS) Test Facility for Testing Explosive Items

    DTIC Science & Technology

    1996-08-01

    Center, Redstone Arsenal, AL Thomas E. Roy and David W. Bagwell AMTEC Corporation, Huntsville, AL ABSTRACT Details of the High Energy Lightning...simulated lightning testing of inerted missiles and inerted explosive items containing electrically initiated explosive trains is to determine the...penetrate the safety cages, which are electrically conductive and grounded, without loss of current. This transmission system consists of six large

  19. Computer Programs for Prediction of Lightning Induced Voltages in Aircraft Electrical Circuits

    DTIC Science & Technology

    1975-04-01

    8217-Mnnmn " ■*> i ■ : mmmmim*mmemmmMmmmmmam*t*ammi m ■■>■ ■ ,-,.->»^~—~—-. ■ - m^m Test techniques and equipment have been designed for subjecting com...are still on the drawing board, when there is as yet no aircraft on which to run tests . To fulfill this need, a program was initiated by the Air...aluated by full-scale simulated lightning tests of the external assemblies in question. Government specifications for some of these devices or

  20. Status of research into lightning effects on aircraft

    NASA Technical Reports Server (NTRS)

    Plumer, J. A.

    1976-01-01

    Developments in aircraft lightning protection since 1938 are reviewed. Potential lightning problems resulting from present trends toward the use of electronic controls and composite structures are discussed, along with presently available lightning 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 lightning 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 lightning 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.

  1. Follow-on cable coupling lightning test. Volume 2: Appendixes A, B, C, and D

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The following information from the follow-on cable coupling lightning test of the Space Shuttle Booster is presented: (1) resistance measurements (cover-to-cover and cover-to-floor plate); (2) resistance measurements (external bond strap-to-case); (3) resistance measurements (internal bond strap-to-case) and; (4) follow-on cable coupling lightning test data plots. The bulk of the document comprises the follow-on cable coupling lightning test data plots.

  2. Preliminary tests of vulnerability of typical aircraft electronics to lightning-induced voltages

    NASA Technical Reports Server (NTRS)

    Plumer, J. A.; Walko, L. C.

    1974-01-01

    Tests made on two pieces of typical aircraft electronics equipment to ascertain their vulnerability to simulated lightning-induced transient voltages representative of those which might occur in flight when the aircraft is struck by lightning were conducted. The test results demonstrated that such equipment can be interfered with or damaged by transient voltages as low as 21 volts peak. Greater voltages can cause failure of semiconductor components within the equipment. The results emphasize a need for establishment of coordinated system susceptibility and component vulnerability criteria to achieve lightning protection of aerospace electrical and electronic systems.

  3. A test technique for measuring lightning-induced voltages on aircraft electrical circuits

    NASA Technical Reports Server (NTRS)

    Walko, L. C.

    1974-01-01

    The development of a test technique used for the measurement of lightning-induced voltages in the electrical circuits of a complete aircraft is described. The resultant technique utilizes a portable device known as a transient analyzer capable of generating unidirectional current impulses similar to lightning current surges, but at a lower current level. A linear relationship between the magnitude of lightning current and the magnitude of induced voltage permitted the scaling up of measured induced values to full threat levels. The test technique was found to be practical when used on a complete aircraft.

  4. Calibration tests on magnetic tape lightning current detectors

    NASA Technical Reports Server (NTRS)

    Crouch, K. E.

    1980-01-01

    The low cost, passive, peak lightning current detector (LCD) invented at the NASA/Kennedy Space Center, uses magnetic audio recording tape to sense the magnitude of the peak magnetic field around a conductor carrying lightning currents. Test results show that the length of audio tape erased was linearly related to the peak simulated lightning currents in a round conductor. Accuracies of + or - 10% were shown for measurements made using a stopwatch readout technique to determine the amount of tape erased by the lightning current. The stopwatch technique is a simple, low cost means of obtaining LCD readouts and can be used in the field to obtain immediate results. Where more accurate data are desired, the tape is played and the output recorded on a strip chart, oscilloscope, or some other means so that measurements can be made on that recording. Conductor dimensions, tape holder dimensions, and tape formulation must also be considered to obtain a more accurate result. If the shape of the conductor is other than circular (i.e., angle, channel, H-beam), an analysis of the magnetic field is required to use an LCD, especially at low current levels.

  5. Tests of the Grobner Basis Solution for Lightning Ground Flash Fraction Retrieval

    NASA Technical Reports Server (NTRS)

    Koshak, William; Solakiewicz, Richard; Attele, Rohan

    2011-01-01

    Satellite lightning imagers such as the NASA Tropical Rainfall Measuring Mission Lightning Imaging Sensor (TRMM/LIS) and the future GOES-R Geostationary Lightning Mapper (GLM) are designed to detect total lightning (ground flashes + cloud flashes). However, there is a desire to discriminate ground flashes from cloud flashes from the vantage point of space since this would enhance the overall information content of the satellite lightning data and likely improve its operational and scientific applications (e.g., in severe weather warning, lightning nitrogen oxides studies, and global electric circuit analyses). A Bayesian inversion method was previously introduced for retrieving the fraction of ground flashes in a set of flashes observed from a satellite lightning imager. The method employed a constrained mixed exponential distribution model to describe the lightning optical measurements. To obtain the optimum model parameters (one of which is the ground flash fraction), a scalar function was minimized by a numerical method. In order to improve this optimization, a Grobner basis solution was introduced to obtain analytic representations of the model parameters that serve as a refined initialization scheme to the numerical optimization. In this study, we test the efficacy of the Grobner basis initialization using actual lightning imager measurements and ground flash truth derived from the national lightning network.

  6. RSRM top hat cover simulator lightning test, volume 2. Appendix A: Resistance measurements. Appendix B: Lightning test data plots

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Resistance measurements are given in graphical for when a simulated lightning discharge strikes on an exposed top hat cover simulator. The test sequence was to measure the electric and magnetic fields induced inside a redesigned solid rocket motor case.

  7. Constructing lightning towers for the Constellation Program and

    NASA Image and Video Library

    2007-11-09

    On Launch Pad 39B at NASA's Kennedy Space Center, pilings are being pounded into the ground to help construct lightning towers for the Constellation Program and Ares/Orion launches. Pad B will be the site of the first Ares vehicle launch, including Ares I-X which is scheduled for April 2009.

  8. Constructing lightning towers for the Constellation Program and

    NASA Image and Video Library

    2007-11-09

    On Launch Pad 39B at NASA's Kennedy Space Center, workers measure the piling being pounded into the ground to help construct lightning towers for the Constellation Program and Ares/Orion launches. Pad B will be the site of the first Ares vehicle launch, including Ares I-X which is scheduled for April 2009.

  9. Constructing lightning towers for the Constellation Program and

    NASA Image and Video Library

    2007-11-09

    On Launch Pad 39B at NASA's Kennedy Space Center, the crane crawler puts a piling into place to be pounded into the ground to help construct lightning towers for the Constellation Program and Ares/Orion launches. Pad B will be the site of the first Ares vehicle launch, including Ares I-X which is scheduled for April 2009.

  10. Constructing lightning towers for the Constellation Program and

    NASA Image and Video Library

    2007-11-09

    On Launch Pad 39B at NASA's Kennedy Space Center, the crane crawler lifts a piling into place to be pounded into the ground to help construct lightning towers for the Constellation Program and Ares/Orion launches. Pad B will be the site of the first Ares vehicle launch, including Ares I-X which is scheduled for April 2009.

  11. Colorado Lightning Mapping Array Collaborations through the GOES-R Visiting Scientist Program

    NASA Technical Reports Server (NTRS)

    Stano, Geoffrey T.; Szoke, Edward; Rydell, Nezette; Cox, Robert; Mazur, Rebecca

    2014-01-01

    For the past two years, the GOES-R Proving Ground has solicited proposals for its Visiting Scientist Program. NASA's Short-term Prediction Research and Transition (SPoRT) Center has used this opportunity to support the GOES-R Proving Ground by expanding SPoRT's total lightning collaborations. In 2012, this expanded the evaluation of SPoRT's pseudo-geostationary lightning mapper product to the Aviation Weather Center and Storm Prediction Center. This year, SPoRT has collaborated with the Colorado Lightning Mapping Array (COLMA) and potential end users. In particular, SPoRT is collaborating with the Cooperative Institute for Research in the Atmosphere (CIRA) and Colorado State University (CSU) to obtain these data in real-time. From there, SPoRT is supporting the transition of these data to the local forecast offices in Boulder, Colorado and Cheyenne, Wyoming as well as to Proving Ground projects (e.g., the Hazardous Weather Testbed's Spring Program and Aviation Weather Center's Summer Experiment). This presentation will focus on the results of this particular Visiting Scientist Program trip. In particular, the COLMA data are being provided to both forecast offices for initial familiarization. Additionally, several forecast issues have been highlighted as important uses for COLMA data in the operational environment. These include the utility of these data for fire weather situations, situational awareness for both severe weather and lightning safety, and formal evaluations to take place in the spring of 2014.

  12. Constructing lightning towers for the Constellation Program and

    NASA Image and Video Library

    2007-11-09

    On Launch Pad 39B at NASA's Kennedy Space Center, the crane crawler lifts a piling off a truck. The piling will be pounded into the ground to help construct lightning towers for the Constellation Program and Ares/Orion launches. Pad B will be the site of the first Ares vehicle launch, including Ares I-X which is scheduled for April 2009.

  13. Development and Testing of Operational Dual-Polarimetric Radar Based Lightning Initiation Forecast Techniques

    NASA Technical Reports Server (NTRS)

    Woodard, Crystal; Carey, Lawrence D.; Petersen, Walter A.; Felix, Mariana; Roeder, William P.

    2011-01-01

    Lightning is one of Earth s natural dangers, destructive not only to life but also physical property. According to the National Weather Service, there are on average 58 lightning fatalities each year, with over 300 related injuries (NWS 2010). The ability to forecast lightning is critical to a host of activities ranging from space vehicle launch operations to recreational sporting events. For example a single lightning strike to a Space Shuttle could cause billions of dollars of damage and possible loss of life. While forecasting that provides longer lead times could provide sporting officials with more time to respond to possible threatening weather events, thus saving the lives of player and bystanders. Many researchers have developed and tested different methods and tools of first flash forecasting, however few have done so using dual-polarimetric radar variables and products on an operational basis. The purpose of this study is to improve algorithms for the short-term prediction of lightning initiation through development and testing of operational techniques that rely on parameters observed and diagnosed using C-band dual-polarimetric radar.

  14. Lightning Launch Commit Criteria for America's Space Program

    NASA Technical Reports Server (NTRS)

    Roeder, W. P.; Sardonia, J. E.; Jacobs, S. C.; Hinson, M. S.; Harms, D. E.; Madura, J. T.; DeSordi, S. P.

    1999-01-01

    The danger of natural and triggered lightning significantly impacts space launch operations supported by the USAF. The lightning Launch Commit Criteria (LCC) are used by the USAF to avoid these lightning threats to space launches. This paper presents a brief overview of the LCC.

  15. Produce documents and media information. [on lightning

    NASA Technical Reports Server (NTRS)

    Alzmann, Melanie A.; Miller, G.A.

    1994-01-01

    Lightning data and information were collected from the United States, Germany, France, Brazil, China, and Australia for the dual purposes of compiling a global lightning data base and producing publications on the Marshall Space Flight Center's lightning program. Research covers the history of lightning, the characteristics of a storm, types of lightningdischarges, observations from airplanes and spacecraft, the future fole of planes and spacecraft in lightning studies, lightning detection networks, and the relationships between lightning and rainfall. Descriptions of the Optical Transient Dectector, the Lightning Imaging Sensor, and the Lightning Mapper Sensor are included.

  16. RSRM top hat cover simulator lightning test, volume 1

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The test sequence was to measure electric and magnetic fields induced inside a redesigned solid rocket motor case when a simulated lightning discharge strikes an exposed top hat cover simulator. The test sequence was conducted between 21 June and 17 July 1990. Thirty-six high rate-of-rise Marx generator discharges and eight high current bank discharges were injected onto three different test article configurations. Attach points included three locations on the top hat cover simulator and two locations on the mounting bolts. Top hat cover simulator and mounting bolt damage and grain cover damage was observed. Overall electric field levels were well below 30 kilowatts/meter. Electric field levels ranged from 184.7 to 345.9 volts/meter and magnetic field levels were calculated from 6.921 to 39.73 amperes/meter. It is recommended that the redesigned solid rocket motor top hat cover be used in Configuration 1 or Configuration 2 as an interim lightning protection device until a lightweight cover can be designed.

  17. Geostationary Lightning Mapper: Lessons Learned from Post Launch Test

    NASA Astrophysics Data System (ADS)

    Edgington, S.; Tillier, C. E.; Demroff, H.; VanBezooijen, R.; Christian, H. J., Jr.; Bitzer, P. M.

    2017-12-01

    Pre-launch calibration and algorithm design for the GOES Geostationary Lightning Mapper resulted in a successful and trouble-free on-orbit activation and post-launch test sequence. Within minutes of opening the GLM aperture door on January 4th, 2017, lightning was detected across the entire field of view. During the six-month post-launch test period, numerous processing parameters on board the instrument and in the ground processing algorithms were fine-tuned. Demonstrated on-orbit performance exceeded pre-launch predictions. We provide an overview of the ground calibration sequence, on-orbit tuning of the instrument, tuning of the ground processing algorithms (event filtering and navigation). We also touch on new insights obtained from analysis of a large and growing archive of raw GLM data, containing 3e8 flash detections derived from over 1e10 full-disk images of the Earth.

  18. The new Section 23 of DO160C/ED14C lightning testing of externally mounted electrical equipment

    NASA Astrophysics Data System (ADS)

    Burrows, B. J. C.

    1991-08-01

    The new Section 23 is introduced which has only very recently been fully approved by the RTCA for incorporation into the first revision of DO160C/ED14C. Full threat lightning direct effects testing of equipment is entirely new to DO160, the only existing lightning testing is transient testing for LRU's (Line Replaceable Units) by pin or cable bundle injection methods, for equipment entirely contained within the airframe and assumed to be unaffected by direct effects. This testing required transients of very low amplitude compared with lightning itself, whereas the tests now to be described involve full threat lightning testing, that is using the previously established severe parameters of lightning appropriate to the Zone, such as 200 kA for Zone 1A as in AC20-136. Direct effects (i.e., damage) testing involves normally the lightning current arc attaching to the object under test (or very near to it) so submitting it to full potential for the electric, mechanical, thermal and shock damage which is caused by high current arcing. Since equipment for any part of the airframe require qualification, tests to demonstrate safety of equipment in fuel vapor regions of the airframe are also included.

  19. Lightning Technology: Proceedings of a Technical Symposium

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Several facets of lightning technology are considered including phenomenology, measurement, detection, protection, interaction, and testing. Lightning electromagnetics, protection of ground systems, and simulated lightning testing are emphasized. The lightning-instrumented F-106 aircraft is described.

  20. Space shuttle program: Lightning protection criteria document

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The lightning environment for space shuttle design is defined and requirements that the design must satisfy to insure protection of the vehicle system from direct and indirect effects of lightning are imposed. Specifications, criteria, and guidelines included provide a practical and logical approach to protection problems.

  1. 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

  2. Lightning fire research in the Rocky Mountains

    Treesearch

    J. S. Barrows

    1954-01-01

    Lightning is the major cause of fires in Rocky Mountain forests. The lightning fire problem is the prime target of a broad research program now known as Project Skyfire. KEYWORDS: lightning, fire research

  3. Global lightning studies

    NASA Technical Reports Server (NTRS)

    Goodman, Steven J.; Wright, Pat; Christian, Hugh; Blakeslee, Richard; Buechler, Dennis; Scharfen, Greg

    1991-01-01

    The global lightning 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 lightning signatures were digitized for the summer months of 1986 to 1987. The relationship is studied between: (1) global and regional lightning 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/lightning 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.

  4. Using Total Lightning Observations to Enhance Lightning Safety

    NASA Technical Reports Server (NTRS)

    Stano, Geoffrey T.

    2012-01-01

    Lightning 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 lightning is far more isolated on a case by case basis, although millions of cloud-to-ground lightning strikes hit this United States each year. While attention is given to larger meteorological events, lightning 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 lightning safety. Already, the meteorological community s understanding of lightning has increased over the last 20 years. Lightning safety is now better addressed with the National Weather Service s access to the National Lightning Detection Network data and enhanced wording in their severe weather warnings. Also, local groups and organizations are working to improve public awareness of lightning 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 lightning. 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 lightning 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

  5. 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

  6. Greased Lightning (GL-10) Flight Testing Campaign

    NASA Technical Reports Server (NTRS)

    Fredericks, William J.; McSwain, Robert G.; Beaton, Brian F.; Klassman, David W.; Theodore, Colin R.

    2017-01-01

    Greased Lightning (GL-10) is an aircraft configuration that combines the characteristics of a cruise efficient airplane with the ability to perform vertical takeoff and landing (VTOL). This aircraft has been designed, fabricated and flight tested at the small unmanned aerial system (UAS) scale. This technical memorandum will document the procedures and findings of the flight test experiments. The GL-10 design utilized two key technologies to enable this unique aircraft design; namely, distributed electric propulsion (DEP) and inexpensive closed loop controllers. These technologies enabled the flight of this inherently unstable aircraft. Overall it has been determined thru flight test that a design that leverages these new technologies can yield a useful VTOL cruise efficient aircraft.

  7. Lightning protection for shuttle propulsion elements

    NASA Technical Reports Server (NTRS)

    Goodloe, Carolyn C.; Giudici, Robert J.

    1991-01-01

    The results of lightning protection analyses and tests are weighed against the present set of waivers to the NASA lightning protection specification. The significant analyses and tests are contrasted with the release of a new and more realistic lightning protection specification, in September 1990, that resulted in an inordinate number of waivers. A variety of lightning 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 lightning strikes at certain times during transportation, launch site operations, and flight. Changes are being evaluated that may improve the odds of withstanding a major lightning 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.

  8. Lightning Effects in the Payload Changeout Room

    NASA Technical Reports Server (NTRS)

    Thomas, Garland L.; Fisher, Franklin A.; Collier, Richard S.; Medelius, Pedro J.

    1997-01-01

    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 lightning strikes to the launch pad lightning 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 lightning simulator to simulate controlled (8 kA) lightning strikes to the catenary wire lightning 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.

  9. Lightning vulnerability of fiber-optic cables.

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

    Martinez, Leonard E.; Caldwell, Michele

    2008-06-01

    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 lightning 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 lightning conditions at the Sandia Lightning Simulator (SLS). Simulated lightning 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 lightning tests performed at the Sandia Lightning 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 lightning conditions.« less

  10. Lightning Jump Algorithm Development for the GOES·R Geostationary Lightning Mapper

    NASA Technical Reports Server (NTRS)

    Schultz. E.; Schultz. C.; Chronis, T.; Stough, S.; Carey, L.; Calhoun, K.; Ortega, K.; Stano, G.; Cecil, D.; Bateman, M.; hide

    2014-01-01

    Current work on the lightning jump algorithm to be used in GOES-R Geostationary Lightning Mapper (GLM)'s data stream is multifaceted due to the intricate interplay between the storm tracking, GLM proxy data, and the performance of the lightning jump itself. This work outlines the progress of the last year, where analysis and performance of the lightning 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 lightning 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 lightning 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 lightning 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/lightning 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).

  11. 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.)

  12. Direct-strike lightning photographs, swept-flash attachment patterns, and flight conditions for storm hazards 1982

    NASA Technical Reports Server (NTRS)

    Zaepfel, K. P.; Fisher, B. D.; Ott, M. S.

    1985-01-01

    As part of the NASA Langley Research Center Storm Hazards Program, 241 thunderstorm penetrations were made in 1982 with an F-106B airplane in order to record direct-strike lightning data and the associated flight conditions. During these penetrations, the airplane received 156 direct lightning strikes; in addition, lightning transient data were recorded from 26 nearby lightning flashes. The tests were conducted within 150 nautical miles of Hampton, Virginia, assisted by ground-based weather-radar guidance from the NASA Wallops Flight Facility. The photographs of the lightning attachments taken from two onboard 16-mm color movie cameras and the associated strike attachment patterns are presented. A table of the flight conditions recorded at the time of each lightning event, and a table in which the data are cross-referenced with the previously published lightning electromagnetic waveform data are included.

  13. Optical Detection of Lightning from Space

    NASA Technical Reports Server (NTRS)

    Boccippio, Dennis J.; Christian, Hugh J.

    1998-01-01

    Optical sensors have been developed to detect lightning 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 lightning detection offers three unique capabilities: (1) the ability to reliably detect lightning over large, often remote, spatial regions, (2) the ability to sample all (IC and CG) lightning, and (3) the ability to detect lightning 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 lightning 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 lightning 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.

  14. PSpice Model of Lightning Strike to a Steel Reinforced Structure

    NASA Astrophysics Data System (ADS)

    Koone, Neil; Condren, Brian

    2003-12-01

    Surges and arcs from lightning can pose hazards to personnel and sensitive equipment, and processes. Steel reinforcement in structures can act as a Faraday cage mitigating lightning effects. Knowing a structure's response to a lightning strike allows hazards associated with lightning to be analyzed. A model of lightning's response in a steel reinforced structure has been developed using PSpice (a commercial circuit simulation). Segments of rebar are modeled as inductors and resistors in series. A program has been written to take architectural information of a steel reinforced structure and "build" a circuit network that is analogous to the network of reinforcement in a facility. A severe current waveform (simulating a 99th percentile lightning strike), modeled as a current source, is introduced in the circuit network, and potential differences within the structure are determined using PSpice. A visual three-dimensional model of the facility displays the voltage distribution across the structure using color to indicate the potential difference relative to the floor. Clear air arcing distances can be calculated from the voltage distribution using a conservative value for the dielectric breakdown strength of air. Potential validation tests for the model will be presented.

  15. JPS heater and sensor lightning qualification

    NASA Technical Reports Server (NTRS)

    Cook, M.

    1989-01-01

    Simulated lightning strike testing of the Redesigned Solid Rocket Motor (RSRM) field joint protection system heater assembly was performed at Thiokol Corp., Wendover Lightning Facility. Testing consisted of subjecting the lightning evaluation test article to simulated lightning 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 lightning discharges only, no heater operating power was applied during the test. The results showed that, for a worst-case lightning 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.

  16. Simulating Realistic Test Data for the European Lightning Imager on MTG using Data from Seviri, TRMM-LIS and ISS-LIS

    NASA Astrophysics Data System (ADS)

    Finke, U.; Blakeslee, R. J.; Mach, D. M.

    2017-12-01

    The next generation of European geostationary weather observing satellites (MTG) will operate an optical lightning location instrument (LI) which will be very similar to the Global Lightning Mapper (GLM) on board of GOES-R. For the development and verification of the product processing algorithms realistic test data are necessary. This paper presents a method of test data generation on the basis of optical lightning data from the LIS instrument and cloud image data from the Seviri radiometer.The basis is the lightning data gathered during the 15 year LIS operation time, particularly the empirical distribution functions of the optical pulse size, duration and radiance as well as the inter-correlation of lightning in space and time. These allow for a realistically structured simulation of lightning test data. Due to its low orbit the instantaneous field of view of the LIS is limited and moving with time. For the generation of test data which cover the geostationary visible disk, the LIS data have to be extended. This is realized by 1. simulating random lightning pulses according to the established distribution functions of the lightning parameters and 2. using the cloud radiometer data of the Seviri instrument on board of the geostationary Meteosat second generation (MSG). Particularly, the cloud top height product (CTH) identifies convective storm clouds wherein the simulation places random lightning pulses. The LIS instrument was recently deployed on the International Space Station (ISS). The ISS orbit reaches higher latitudes, particularly Europe. The ISS-LIS data is analyzed for single observation days. Additionally, the statistical distribution of parameters such as radiance, footprint size, and space time correlation of the groups are compared against the long time statistics from TRMM-LIS.Optical lightning detection efficiency from space is affected by the solar radiation reflected from the clouds. This effect is changing with day and night areas across the

  17. 14 CFR 35.38 - Lightning strike.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...

  18. 14 CFR 35.38 - Lightning strike.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...

  19. 14 CFR 35.38 - Lightning strike.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...

  20. 14 CFR 35.38 - Lightning strike.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...

  1. 14 CFR 35.38 - Lightning strike.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... STANDARDS: PROPELLERS Tests and Inspections § 35.38 Lightning strike. The applicant must demonstrate, by tests, analysis based on tests, or experience on similar designs, that the propeller can withstand a lightning strike without causing a major or hazardous propeller effect. The limit to which the propeller has...

  2. Lightning protection of distribution systems

    NASA Astrophysics Data System (ADS)

    Darveniza, M.; Uman, M. A.

    1982-09-01

    Research work on the lightning 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 lightning in the Tampa Bay area, and to identify the lightning 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 lightning - e.g., electric and magnetic fields of cloud and ground flashes; data from automated monitoring of lightning 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.

  3. Evaluation of NASA SPoRT's Pseudo-Geostationary Lightning Mapper Products in the 2011 Spring Program

    NASA Technical Reports Server (NTRS)

    Stano, Geoffrey T.; Carcione, Brian; Siewert, Christopher; Kuhlman, Kristin M.

    2012-01-01

    NASA's Short-term Prediction Research and Transition (SPoRT) program is a contributing partner with the GOES-R Proving Ground (PG) preparing forecasters to understand and utilize the unique products that will be available in the GOES-R era. This presentation emphasizes SPoRT s actions to prepare the end user community for the Geostationary Lightning Mapper (GLM). This preparation is a collaborative effort with SPoRT's National Weather Service partners, the National Severe Storms Laboratory (NSSL), and the Hazardous Weather Testbed s Spring Program. SPoRT continues to use its effective paradigm of matching capabilities to forecast problems through collaborations with our end users and working with the developers at NSSL to create effective evaluations and visualizations. Furthermore, SPoRT continues to develop software plug-ins so that these products will be available to forecasters in their own decision support system, AWIPS and eventually AWIPS II. In 2009, the SPoRT program developed the original pseudo geostationary lightning mapper (PGLM) flash extent product to demonstrate what forecasters may see with GLM. The PGLM replaced the previous GLM product and serves as a stepping-stone until the AWG s official GLM proxy is ready. The PGLM algorithm is simple and can be applied to any ground-based total lightning network. For 2011, the PGLM used observations from four ground-based networks (North Alabama, Kennedy Space Center, Oklahoma, and Washington D.C.). While the PGLM is not a true proxy product, it is intended as a tool to train forecasters about total lightning as well as foster discussions on product visualizations and incorporating GLM-resolution data into forecast operations. The PGLM has been used in 2010 and 2011 and is likely to remain the primary lightning training tool for the GOES-R program for the near future. This presentation will emphasize the feedback received during the 2011 Spring Program. This will discuss several topics. Based on feedback

  4. LOFAR Lightning Imaging: Mapping Lightning With Nanosecond Precision

    NASA Astrophysics Data System (ADS)

    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.

    2018-03-01

    Lightning mapping technology has proven instrumental in understanding lightning. In this work we present a pipeline that can use lightning 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 lightning 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 lightning flash. We also show that LOFAR is the first lightning mapping system that is sensitive to the spatial structure of the electrical current during individual lightning leader steps.

  5. Lightning research: A user's lament

    NASA Technical Reports Server (NTRS)

    Golub, C. N.

    1984-01-01

    As a user of devices and procedures for lightning protection, the author is asking the lightning 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 lightning technology--the use of the Eastern Test Range and its extensive resources as a proving ground for their experiment in the lightning capital of the United States. A current example is given--a joint lightning characterization project to take place there. Typical resources are listed.

  6. The Development of the Puerto Rico Lightning Detection Network for Meteorological Research

    NASA Technical Reports Server (NTRS)

    Legault, Marc D.; Miranda, Carmelo; Medin, J.; Ojeda, L. J.; Blakeslee, Richard J.

    2011-01-01

    A land-based Puerto Rico Lightning Detection Network (PR-LDN) dedicated to the academic research of meteorological phenomena has being developed. Five Boltek StormTracker PCI-Receivers with LTS-2 Timestamp Cards with GPS and lightning detectors were integrated to Pentium III PC-workstations running the CentOS linux operating system. The Boltek detector linux driver was compiled under CentOS, modified, and thoroughly tested. These PC-workstations with integrated lightning detectors were installed at five of the University of Puerto Rico (UPR) campuses distributed around the island of PR. The PC-workstations are left on permanently in order to monitor lightning activity at all times. Each is networked to their campus network-backbone permitting quasi-instantaneous data transfer to a central server at the UPR-Bayam n campus. Information generated by each lightning detector is managed by a C-program developed by us called the LDN-client. The LDN-client maintains an open connection to the central server operating the LDN-server program where data is sent real-time for analysis and archival. The LDN-client also manages the storing of data on the PC-workstation hard disk. The LDN-server software (also an in-house effort) analyses the data from each client and performs event triangulations. Time-of-arrival (TOA) and related hybrid algorithms, lightning-type and event discriminating routines are also implemented in the LDN-server software. We also have developed software to visually monitor lightning events in real-time from all clients and the triangulated events. We are currently monitoring and studying the spatial, temporal, and type distribution of lightning strikes associated with electrical storms and tropical cyclones in the vicinity of Puerto Rico.

  7. Lightning-Related Indicators for National Climate Assessment (NCA) Studies

    NASA Technical Reports Server (NTRS)

    Koshak, W.

    2017-01-01

    Changes in climate can affect the characteristics of lightning (e.g., number of flashes that occur in a region, return stroke current and multiplicity, polarity of charge deposited to ground, and the lightning cloud-top optical energy emission). The NASA/MSFC Lightning Analysis Tool (LAT) monitors these and other quantities in support of the National Climate Assessment (NCA) program. Changes in lightning characteristics lead to changes in lightning-caused impacts to humans (e.g., fatalities, injuries, crop/property damage, wildfires, airport delays, changes in air quality).

  8. Synthesis and testing of a conducting polymeric composite material for lightning strike protection applications

    NASA Astrophysics Data System (ADS)

    Katunin, A.; Krukiewicz, K.; Turczyn, R.; Sul, P.; Łasica, A.; Catalanotti, G.; Bilewicz, M.

    2017-02-01

    Lightning strike protection is one of the important issues in the modern maintenance problems of aircraft. This is due to a fact that the most of exterior elements of modern aircraft is manufactured from polymeric composites which are characterized by isolating electrical properties, and thus cannot carry the giant electrical charge when the lightning strikes. This causes serious damage of an aircraft structure and necessity of repairs and tests before returning a vehicle to operation. In order to overcome this problem, usually metallic meshes are immersed in the polymeric elements. This approach is quite effective, but increases a mass of an aircraft and significantly complicates the manufacturing process. The approach proposed by the authors is based on a mixture of conducting and dielectric polymers. Numerous modeling studies which are based on percolation clustering using kinetic Monte Carlo methods, finite element modeling of electrical and mechanical properties, and preliminary experimental studies, allow achieving an optimal content of conducting particles in a dielectric matrix in order to achieve possibly the best electrical conductivity and mechanical properties, simultaneously. After manufacturing the samples with optimal content of a conducting polymer, mechanical and electrical characterization as well as high-voltage testing was performed. The application of such a material simplifies manufacturing process and ensures unique properties of aircraft structures, which allows for minimizing damage after lightning strike, as well as provide electrical bounding and grounding, interference shielding, etc. The proposed solution can minimize costs of repair, testing and certification of aircraft structures damaged by lightning strikes.

  9. Post launch calibration and testing of the Geostationary Lightning Mapper on GOES-R satellite

    NASA Astrophysics Data System (ADS)

    Rafal, Marc; Clarke, Jared T.; Cholvibul, Ruth W.

    2016-05-01

    The Geostationary Operational Environmental Satellite R (GOES-R) series is the planned next generation of operational weather satellites for the United States National Oceanic and Atmospheric Administration (NOAA). The National Aeronautics and Space Administration (NASA) is procuring the GOES-R spacecraft and instruments with the first launch of the GOES-R series planned for October 2016. Included in the GOES-R Instrument suite is the Geostationary Lightning Mapper (GLM). GLM is a single-channel, near-infrared optical detector that can sense extremely brief (800 μs) transient changes in the atmosphere, indicating the presence of lightning. GLM will measure total lightning activity continuously over the Americas and adjacent ocean regions with near-uniform spatial resolution of approximately 10 km. Due to its large CCD (1372x1300 pixels), high frame rate, sensitivity and onboard event filtering, GLM will require extensive post launch characterization and calibration. Daytime and nighttime images will be used to characterize both image quality criteria inherent to GLM as a space-based optic system (focus, stray light, crosstalk, solar glint) and programmable image processing criteria (dark offsets, gain, noise, linearity, dynamic range). In addition ground data filtering will be adjusted based on lightning-specific phenomenology (coherence) to isolate real from false transients with their own characteristics. These parameters will be updated, as needed, on orbit in an iterative process guided by pre-launch testing. This paper discusses the planned tests to be performed on GLM over the six-month Post Launch Test period to optimize and demonstrate GLM performance.

  10. Post Launch Calibration and Testing of the Geostationary Lightning Mapper on GOES-R Satellite

    NASA Technical Reports Server (NTRS)

    Rafal, Marc; Cholvibul, Ruth; Clarke, Jared

    2016-01-01

    The Geostationary Operational Environmental Satellite R (GOES-R) series is the planned next generation of operational weather satellites for the United States National Oceanic and Atmospheric Administration (NOAA). The National Aeronautics and Space Administration (NASA) is procuring the GOES-R spacecraft and instruments with the first launch of the GOES-R series planned for October 2016. Included in the GOES-R Instrument suite is the Geostationary Lightning Mapper (GLM). GLM is a single-channel, near-infrared optical detector that can sense extremely brief (800 s) transient changes in the atmosphere, indicating the presence of lightning. GLM will measure total lightning activity continuously over the Americas and adjacent ocean regions with near-uniform spatial resolution of approximately 10 km. Due to its large CCD (1372x1300 pixels), high frame rate, sensitivity and onboard event filtering, GLM will require extensive post launch characterization and calibration. Daytime and nighttime images will be used to characterize both image quality criteria inherent to GLM as a space-based optic system (focus, stray light, crosstalk, solar glint) and programmable image processing criteria (dark offsets, gain, noise, linearity, dynamic range). In addition ground data filtering will be adjusted based on lightning-specific phenomenology (coherence) to isolate real from false transients with their own characteristics. These parameters will be updated, as needed, on orbit in an iterative process guided by pre-launch testing. This paper discusses the planned tests to be performed on GLM over the six-month Post Launch Test period to optimize and demonstrate GLM performance.

  11. 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.

  12. NASA Manned Launch Vehicle Lightning Protection Development

    NASA Technical Reports Server (NTRS)

    McCollum, Matthew B.; Jones, Steven R.; Mack, Jonathan D.

    2009-01-01

    Historically, the National Aeronautics and Space Administration (NASA) relied heavily on lightning avoidance to protect launch vehicles and crew from lightning 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 lightning. A review of current Space Shuttle lightning constraints and protection methodology will be presented, as well as a historical review of Space Shuttle lightning requirements and design. The Space Shuttle lightning requirements document, NSTS 07636, Lightning Protection, Test and Analysis Requirements, (originally published as document number JSC 07636, Lightning Protection Criteria Document) was developed in response to the Apollo 12 lightning event and other experiences with NASA and the Department of Defense launch vehicles. This document defined the lightning 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) lightning 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 lightning design requirements. The development and derivation of these requirements will be presented. As budget and schedule constraints hampered lightning protection design and verification efforts, the Space Shuttle elements waived the design requirements and relied on lightning avoidance in the form of launch commit criteria (LCC) constraints and a catenary wire system for lightning protection at the launch pads. A better understanding of the lightning environment has highlighted the vulnerability of the protection schemes and associated risk to the vehicle

  13. Analysis and calculation of lightning-induced voltages in aircraft electrical circuits

    NASA Technical Reports Server (NTRS)

    Plumer, J. A.

    1974-01-01

    Techniques to calculate the transfer functions relating lightning-induced voltages in aircraft electrical circuits to aircraft physical characteristics and lightning current parameters are discussed. The analytical work was carried out concurrently with an experimental program of measurements of lightning-induced voltages in the electrical circuits of an F89-J aircraft. A computer program, ETCAL, developed earlier to calculate resistive and inductive transfer functions is refined to account for skin effect, providing results more valid over a wider range of lightning waveshapes than formerly possible. A computer program, WING, is derived to calculate the resistive and inductive transfer functions between a basic aircraft wing and a circuit conductor inside it. Good agreement is obtained between transfer inductances calculated by WING and those reduced from measured data by ETCAL. This computer program shows promise of expansion to permit eventual calculation of potential lightning-induced voltages in electrical circuits of complete aircraft in the design stage.

  14. [Neurological diseases after lightning strike : Lightning strikes twice].

    PubMed

    Gruhn, K M; Knossalla, Frauke; Schwenkreis, Peter; Hamsen, Uwe; Schildhauer, Thomas A; Tegenthoff, Martin; Sczesny-Kaiser, Matthias

    2016-06-01

    Lightning strikes rarely occur but 85 % of patients have lightning-related neurological complications. This report provides an overview about different modes of energy transfer and neurological conditions related to lightning strikes. Moreover, two case reports demonstrate the importance of interdisciplinary treatment and the spectrum of neurological complications after lightning strikes.

  15. Lightning Radio Source Retrieval Using Advanced Lightning Direction Finder (ALDF) Networks

    NASA Technical Reports Server (NTRS)

    Koshak, William J.; Blakeslee, Richard J.; Bailey, J. C.

    1998-01-01

    A linear algebraic solution is provided for the problem of retrieving the location and time of occurrence of lightning ground strikes from an Advanced Lightning Direction Finder (ALDF) network. The ALDF network measures field strength, magnetic bearing and arrival time of lightning 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 lightning 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 Lightning Detection Network (NLDN) and discussed in Cummins et al.(1993, 1995, 1998).

  16. Lightning Protection and Structural Bonding for the B2 Test Stand

    NASA Technical Reports Server (NTRS)

    Kinard, Brandon

    2015-01-01

    With the privatization of the space industry, NASA has entered a new era. To explore deeper parts of the solar system, NASA is developing a new spacecraft, the Space Launch System (SLS), capable of reaching these destinations, such as an asteroid or Mars. However, the test stand that is capable of testing the stage has been unused for many years. In addition to the updating/repair of the stand, more steel is being added to fully support the SLS. With all these modifications, the lightning protection system must be brought up to code to assure the protection of all personnel and assets. Structural bonding is a part of the lightning protection system. The focus of this project was to assure proper structural bonding. To begin, all relevant technical standards and the construction specifications were reviewed. This included both the specifications for the lightning protection and for general construction. The drawings were reviewed as well. From the drawings, bolted structural joints were reviewed to determine whether bonding was necessary. Several bolted joints were determined to need bonding according to the notes in the drawings. This exceeds the industry standards. The bolted joints are an electrically continuous joint. During tests, the stand experiences heavy vibration that may weaken the continuity of the bolted joint. Therefore, the secondary bonding is implemented to ensure that the structural joint has low resistance. If the structural joint has a high resistance because of corrosion, a potential gradient can occur that can cause a side flash. Damage, injury, or death can occur from a side flash so they are to be prevented. A list of the identified structural joints was compiled and sent to the contractor to be bonded. That covers the scope of this project.

  17. Lightning-Related Indicators for National Climate Assessment (NCA) Studies

    NASA Astrophysics Data System (ADS)

    Koshak, W. J.

    2017-12-01

    With the recent advent of space-based lightning mappers [i.e., the Geostationary Lightning Mapper (GLM) on GOES-16, and the Lightning Imaging Sensor (LIS) on the International Space Station], improved investigations on the inter-relationships between lightning and climate are now possible and can directly support the goals of the National Climate Assessment (NCA) program. Lightning 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 lightning (e.g., frequency, current amplitudes, multiplicity, polarity) that in turn leads to changes in lightning-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 Lightning Analysis Tool (LAT). It includes key findings on the development of different types of lightning flash energy indicators derived from space-based lightning observations, and demonstrates how these indicators can be used to estimate trends in LNOx across the continental US.

  18. Camp Blanding Lightning Mapping Array

    NASA Technical Reports Server (NTRS)

    Blakeslee,Richard; Christian, Hugh; Bailey, Jeffrey; Hall, John; Uman, Martin; Jordan, Doug; Krehbiel, Paul; Rison, William; Edens, Harald

    2011-01-01

    A seven station, short base-line Lightning Mapping Array was installed at the Camp Blanding International Center for Lightning Research and Testing (ICLRT) during April 2011. This network will support science investigations of Terrestrial Gamma-Ray Flashes (TGFs) and lightning initiation using rocket triggered lightning 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.

  19. Post Launch Calibration and Testing of the Geostationary Lightning Mapper on the GOES-R Satellite

    NASA Technical Reports Server (NTRS)

    Rafal, Marc D.; Clarke, Jared T.; Cholvibul, Ruth W.

    2016-01-01

    The Geostationary Operational Environmental Satellite R (GOES-R) series is the planned next generation of operational weather satellites for the United States National Oceanic and Atmospheric Administration (NOAA). The National Aeronautics and Space Administration (NASA) is procuring the GOES-R spacecraft and instruments with the first launch of the GOES-R series planned for October 2016. Included in the GOES-R Instrument suite is the Geostationary Lightning Mapper (GLM). GLM is a single-channel, near-infrared optical detector that can sense extremely brief (800 microseconds) transient changes in the atmosphere, indicating the presence of lightning. GLM will measure total lightning activity continuously over the Americas and adjacent ocean regions with near-uniform spatial resolution of approximately 10 km. Due to its large CCD (1372x1300 pixels), high frame rate, sensitivity and onboard event filtering, GLM will require extensive post launch characterization and calibration. Daytime and nighttime images will be used to characterize both image quality criteria inherent to GLM as a space-based optic system (focus, stray light, crosstalk, solar glint) and programmable image processing criteria (dark offsets, gain, noise, linearity, dynamic range). In addition ground data filtering will be adjusted based on lightning-specific phenomenology (coherence) to isolate real from false transients with their own characteristics. These parameters will be updated, as needed, on orbit in an iterative process guided by pre-launch testing. This paper discusses the planned tests to be performed on GLM over the six-month Post Launch Test period to optimize and demonstrate GLM performance.

  20. Nowcasting and forecasting of lightning activity: the Talos project.

    NASA Astrophysics Data System (ADS)

    Lagouvardos, Kostas; Kotroni, Vassiliki; Kazadzis, Stelios; Giannaros, Theodore; Karagiannidis, Athanassios; Galanaki, Elissavet; Proestakis, Emmanouil

    2015-04-01

    Thunder And Lightning Observing System (TALOS) is a research program funded by the Greek Ministry of Education with the aim to promote excellence in the field of lightning meteorology. The study focuses on exploring the real-time observations provided by the ZEUS lightning 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: - lightning climatology over the Mediterranean focusing on lightning spatial and temporal distribution, on the relation of lightning with topographical features and instability and on the importance of aerosols in lightning initiation and enhancement. - nowcasting of lightning activity over Greece, with emphasis on the operational aspects of this endeavour. The nowcasting tool is based on the use of lightning data complemented by high-time resolution METEOSAT imagery. - forecasting of lightning activity over Greece based on the use of WRF numerical weather prediction model. - assimilation of lightning 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.

  1. The Sandia transportable triggered lightning instrumentation facility

    NASA Technical Reports Server (NTRS)

    Schnetzer, George H.; Fisher, Richard J.

    1991-01-01

    Development of the Sandia Transportable Triggered Lightning 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 lightning 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 lightning 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 lightning 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 lightning facility for specialized test applications.

  2. Flash Detection Efficiencies of Long Range Lightning Detection Networks During GRIP

    NASA Technical Reports Server (NTRS)

    Mach, Douglas M.; Bateman, Monte G.; Blakeslee, Richard J.

    2012-01-01

    We flew our Lightning Instrument Package (LIP) on the NASA Global Hawk as a part of the Genesis and Rapid Intensification Processes (GRIP) field program. The GRIP program was a NASA Earth science field experiment during the months of August and September, 2010. During the program, the LIP detected lighting from 48 of the 213 of the storms overflown by the Global Hawk. The time and location of tagged LIP flashes can be used as a "ground truth" dataset for checking the detection efficiency of the various long or extended range ground-based lightning detection systems available during the GRIP program. The systems analyzed included Vaisala Long Range (LR), Vaisala GLD360, the World Wide Lightning Location Network (WWLLN), and the Earth Networks Total Lightning Network (ENTLN). The long term goal of our research is to help understand the advantages and limitations of these systems so that we can utilize them for both proxy data applications and cross sensor validation of the GOES-R Geostationary Lightning Mapper (GLM) sensor when it is launched in the 2015 timeframe.

  3. Summary of lightning activities by NASA for the Apollo Soyuz test project: Supplement no. 1 to Apollo Soyuz mission evaluation report

    NASA Technical Reports Server (NTRS)

    1976-01-01

    To avoid the possibility of an unnecessary launch delay, a special program was initiated to provide aircraft measurement of electric fields at various altitudes over the Apollo vehicle launch pad. Eight aircraft, each equipped with electric field meters, were used in the program. This program and some of the more important findings are discussed. Also included is a summary of the history of manned space vehicle involvement with lightning, a brief description of the lightning instrumentation in use at KSC (Kennedy Space Center) at the time of the Apollo Soyuz mission and a discussion of the airborne instrumentation and related data.

  4. A Model Lightning Safety Policy for Athletics

    PubMed Central

    Bennett, Brian L.

    1997-01-01

    Objective: The purpose of this paper is to present a model policy on lightning safety for athletic trainers. Background: Among college athletic programs in the United States there is a serious lack of written policy on lightning safety. Available evidence shows that most National Collegiate Athletic Association (NCAA) Division I institutions, even though they are located in high lightning activity areas of the country, do not have formal, written lightning safety policies. Clinical Advantages/ Recommendations: The policy presented herein, which is at the forefront of such policies, is the lightning 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 lightning 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 lightning activity. PMID:16558459

  5. 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

    2015-01-01

    Lightning one of the most dangerous weather-related phenomena, especially as many jobs and activities occur outdoors, presenting risk from a lightning strike. Cloud-to-ground (CG) lightning 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 lightning 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 lightning causing a large component of the fatalities, in addition to tornadoes and flash flooding. Related to the aviation industry, CG lightning 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 lightning 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 lightning, both of CG and of any lightning (e.g, in-cloud, cloud-to-cloud). For this project three lightning nowcasting methodologies will be combined: (1) a GOESbased 0-1 hour lightning initiation (LI) product (Harris et al. 2010; Iskenderian et al. 2012), (2) a High Resolution Rapid Refresh (HRRR) lightning probability and forecasted lightning flash density product, such that a quantitative amount of lightning (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 "lightning jump" (LJ) methodology (Shultz et al

  6. 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.

  7. A first look at lightning energy determined from GLM

    NASA Astrophysics Data System (ADS)

    Bitzer, P. M.; Burchfield, J. C.; Brunner, K. N.

    2017-12-01

    The Geostationary Lightning 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 lightning metrics such as detection efficiency, false alarm rate, and location accuracy, there are other attributes of the lightning discharge that are provided by GLM data. Namely, the optical energy radiated by lightning may provide information useful for lightning physics and the relationship of lightning energy to severe weather development. This work presents initial estimates of the lightning 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 lightning instrumentation, including a lightning 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.

  8. Rationales for the Lightning Flight-Commit Criteria

    NASA Technical Reports Server (NTRS)

    Willett, John C. (Editor); Merceret, Francis J.; Krider, E. Philip; Dye, James E.; OBrien, T. Paul; Rust, W. David; Walterscheid, Richard L.; Madura, John T.; Christian, Hugh J.

    2010-01-01

    Since natural and artificially-initiated (or "triggered") lightning are demonstrated hazards to the launch of space vehicles, the American space program has responded by establishing a set of Lightning Flight Commit Criteria (LFCC), also known as Lightning Launch Commit Criteria (LLCC), and associated Definitions to mitigate the risk. The LLCC apply to all Federal Government ranges and similar LFCC have been adopted by the Federal Aviation Administration for application at state-operated and private spaceports. The LLCC and Definitions have been developed, reviewed, and approved over the years of the American space program, progressing from relatively simple rules in the mid-twentieth century (that were inadequate) to a complex suite for launch operations in the early 21st century. During this evolutionary process, a "Lightning Advisory Panel (LAP)" of top American scientists in the field of atmospheric electricity was established to guide it. Details of this process are provided in a companion document entitled "A History of the Lightning Launch Commit Criteria and the Lightning Advisory Panel for America s Space program" which is available as NASA Special Publication 2010-216283. As new knowledge and additional operational experience have been gained, the LFCC/LLCC have been updated to preserve or increase their safety and to increase launch availability. All launches of both manned and unmanned vehicles at all Federal Government ranges now use the same rules. This simplifies their application and minimizes the cost of the weather infrastructure to support them. Vehicle operators and Range safety personnel have requested that the LAP provide a detailed written rationale for each of the LFCC so that they may better understand and appreciate the scientific and operational justifications for them. This document provides the requested rationales

  9. The start of lightning: Evidence of bidirectional lightning initiation.

    PubMed

    Montanyà, Joan; van der Velde, Oscar; Williams, Earle R

    2015-10-16

    Lightning 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, lightning inception is typically hidden from sight of camera systems used in research. Other technology such as lightning mapping systems based on radio waves can typically detect only some aspects of the lightning initiation process and subsequent development of positive and negative leaders. We report here a serendipitous recording of bidirectional lightning 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 lightning initiation, propagation and a return stroke as in negative cloud-to-ground flashes, upon connection to another lightning channel - without any masking by cloud.

  10. Global Lightning Activity

    NASA Technical Reports Server (NTRS)

    Christian, Hugh J.

    2004-01-01

    Our knowledge of the global distribution of lightning has improved dramatically since the advent of spacebased lightning observations. Of major importance was the 1995 launch of the Optical Transient Detector (OTD), followed in 1997 by the launch of the Lightning Imaging Sensor (LIS). Together, these instruments have generated a continuous eight-year record of global lightning activity. These lightning observations have provided a new global perspective on total lightning activity. For the first time, total lightning 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 lightning 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 lightning 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 lightning has lead to improved insight into the correlation between lightning and storm development. The relationship between updraft development and lightning activity is now well established and presents an opportunity for providing a new mechanism for remotely monitoring storm development. In this concept, lightning 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 lightning measurements, will discuss how lightning observations can be used to monitor severe weather, and

  11. Planetary lightning

    NASA Astrophysics Data System (ADS)

    Russell, C. T.; Clayton, R. N.; Buseck, P. R.; Hua, X.; Holsapple, K. A.; Esposito, L. W.; Aherns, T. J.; Hecht, J.

    The present state of knowledge concerning lightning on the planets is reviewed. Voyager data have clearly established the presence of lightning discharges at each of the four Jovian planets. In situ data for lightning on Venus are discussed in some detail, including reported quantitative occurrence rates and hypotheses concerning the relationship of Venusian lightning to VLF bursts observed in the Venus atmosphere.

  12. Oceanic Lightning versus Continental Lightning: VLF Peak Current Discrepancies

    NASA Astrophysics Data System (ADS)

    Dupree, N. A., Jr.; Moore, R. C.

    2015-12-01

    Recent analysis of the Vaisala global lightning data set GLD360 suggests that oceanic lightning tends to exhibit larger peak currents than continental lightning (lightning occurring over land). The GLD360 peak current measurement is derived from distant measurements of the electromagnetic fields emanated during the lightning flash. Because the GLD360 peak current measurement is a derived quantity, it is not clear whether the actual peak currents of oceanic lightning 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 lightning can be significantly stronger than for continental lightning. 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 lightning 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.

  13. The 1983 direct strike lightning data, part 1

    NASA Technical Reports Server (NTRS)

    Thomas, Mitchel E.

    1985-01-01

    Data waveforms are presented which were obtained during the 1983 direct strike lightning tests utilizing the NASA F106-B aircraft specially instrumented for lightning 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 lightning. Part 1 contains 435 pages of lightning strike data in chart form.

  14. The 1983 direct strike lightning data, part 2

    NASA Technical Reports Server (NTRS)

    Thomas, Mitchel E.

    1985-01-01

    Data waveforms are presented which were obtained during the 1983 direct strike lightning tests utilizing the NASA F106-B aircraft specially instrumented for lightning 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 lightning. Part 2 contains 443 pages of lightning strike data in chart form.

  15. Lightning electromagnetics

    NASA Technical Reports Server (NTRS)

    Wahid, Parveen

    1995-01-01

    This project involved the determination of the effective radiated power of lightning 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 lightning 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.

  16. A History of the Lightning Launch Commit Criteria and the Lightning Advisory Panel for America's Space Program

    NASA Technical Reports Server (NTRS)

    Merceret, Francis J. (Editor); Willett, John C.; Christian, Hugh J.; Dye, James E.; Krider, E. Phillip; Madura, John T.; OBrien, T. Paul; Rust, W. David; Walterscheid, Richard L.

    2010-01-01

    The history of the Lightning Launch Commit Criteria (LLCC) used at all spaceports under the jurisdiction of the United States is provided. The formation and history of the Lightning Advisory Panel (LAP) that now advises NASA, the Air Force and the Federal Aviation Administration on LLCC development and improvement is emphasized. The period covered extends from the early days of space flight through 2010. Extensive appendices provide significant detail about important aspects that are only summarized in the main text.

  17. Systems tunnel linear shaped charge lightning strike

    NASA Technical Reports Server (NTRS)

    Cook, M.

    1989-01-01

    Simulated lightning strike testing of the systems tunnel linear shaped charge (LSC) was performed at the Thiokol Lightning Test Complex in Wendover, Utah, on 23 Jun. 1989. The test article consisted of a 160-in. section of the LSC enclosed within a section of the systems tunnel. The systems tunnel was bonded to a section of a solid rocket motor case. All test article components were full scale. The systems tunnel cover of the test article was subjected to three discharges (each discharge was over a different grounding strap) from the high-current generator. The LSC did not detonate. All three grounding straps debonded and violently struck the LSC through the openings in the systems tunnel floor plates. The LSC copper surface was discolored around the areas of grounding strap impact, and arcing occurred at the LSC clamps and LSC ends. This test verified that the present flight configuration of the redesigned solid rocket motor systems tunnel, when subjected to simulated lightning strikes with peak current levels within 71 percent of the worst-case lightning strike condition of NSTS-07636, is adequate to prevent LSC ignition. It is therefore recommended that the design remain unchanged.

  18. 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.

  19. Effects of lightning on operations of aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Fisher, Bruce D.

    1989-01-01

    Traditionally, aircraft lightning 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 lightning protection measures be incorporated in the design of such aircraft in order to maintain the excellent lightning safety record presently enjoyed by transport aircraft. In addition, several recent lightning 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 lightning. The recent findings of the NASA Storm Hazards Program were reviewed as they pertain to the atmospheric conditions conducive to aircraft lightning strikes. These data are then compared to recent summaries of lightning strikes to operational aircraft fleets. Finally, the new launch commit criteria for triggered lightning 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 lightning 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 lightning research.

  20. Principles of Lightning Physics

    NASA Astrophysics Data System (ADS)

    Mazur, Vladislav

    2016-12-01

    Principles of Lightning Physics presents and discusses the most up-to-date physical concepts that govern many lightning events in nature, including lightning interactions with man-made structures, at a level suitable for researchers, advanced students and well-educated lightning enthusiasts. The author's approach to understanding lightning-to seek out, and show what is common to all lightning flashes-is illustrated by an analysis of each type of lightning and the multitude of lightning-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 lightning and the lexicon of terms and definitions presently used in lightning research.

  1. Combining satellite-based fire observations and ground-based lightning detections to identify lightning fires across the conterminous USA

    USGS Publications Warehouse

    Bar-Massada, A.; Hawbaker, T.J.; Stewart, S.I.; Radeloff, V.C.

    2012-01-01

    Lightning 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 lightning 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 lightning detections from the National Lightning Detection Network to identify lightning fires across the conterminous US from 2000 to 2008. The algorithm searches for spatiotemporal conjunctions of MODIS fire clusters and NLDN detected lightning strikes, given a spatiotemporal lag between lightning strike and fire ignition. The algorithm revealed distinctive spatial patterns of lightning 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 lightning fire occurrence, and especially lightning 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 lightning fire activity, and can be used to identify the broad scale factors controlling fire occurrence.

  2. The Statistic Results of the ISUAL Lightning Survey

    NASA Astrophysics Data System (ADS)

    Chuang, Chia-Wen; Bing-Chih Chen, Alfred; Liu, Tie-Yue; Lin, Shin-Fa; Su, Han-Tzong; Hsu, Rue-Ron

    2017-04-01

    The ISUAL (Imager for Sprites and Upper Atmospheric Lightning) onboard FORMOSAT-2 is the first science payload dedicated to the study of the lightning-induced transient luminous events (TLEs). Transient events, including TLEs and lightning, 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 lightning 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 lightning, can act as a long-term global lightning survey. These huge amount of events cannot be processed manually as TLEs do, therefore, a data pipeline is developed to scan lightning 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.

  3. 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.

  4. Global Lightning Activity

    NASA Technical Reports Server (NTRS)

    Christian, Hugh

    2003-01-01

    Our knowledge of the global distribution of lightning has improved dramatically since the 1995 launch of the Optical Transient Detector (OTD) followed in 1997 by the launch of the Lightning Imaging Sensor (LIS). Together, these instruments have generated a continuous seven-year record of global lightning activity. These lightning observations have provided a new global perspective on total lightning activity. For the first time, total lightning activity (CG and IC) has been observed over large regions with high detection efficiencies and accurate geographic location. This has produced new insights into lightning 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 lightning 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 lightning has lead to improved insight into the correlation between lightning and storm development. The relationship between updraft development and lightning activity is now well established and presents an opportunity for providing a new mechanism for remotely monitoring storm development. In this concept, lightning 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.

  5. Lightning and Climate

    NASA Astrophysics Data System (ADS)

    Williams, E.

    2012-12-01

    Lightning is of interest in the domain of climate change for several reasons: (1) thunderstorms are extreme forms of moist convection, and lightning 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 lightning can be monitored continuously and inexpensively within a natural framework (the Earth-ionosphere waveguide and Schumann resonances). Lightning and temperature, and lightning and upper tropospheric water vapor, are positively correlated on weather-related time scales (diurnal, semiannual, and annual) with a lightning temperature sensitivity of order 10% per oC. Lightning also follows temperature variations on the ENSO time scale, both locally and globally. The response of lightning in some of its extreme forms (exceptional flash rates and the prevalence of sprite-producing mesoscale lightning, for example) to temperature variations will be addressed. Consistently obtained records of lightning 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 lightning record for climate studies, with evidence for increases over decades in urban areas. Global records of lightning 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 lightning 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 lightning in the northern hemisphere, where the global warming is most pronounced. The quantity more fundamental than temperature for lightning control is cloud buoyancy

  6. 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

  7. Geostationary Lightning Mapper for GOES-R

    NASA Technical Reports Server (NTRS)

    Goodman, Steven; Blakeslee, Richard; Koshak, William

    2007-01-01

    The Geostationary Lightning Mapper (GLM) is a single channel, near-IR optical detector, used to detect, locate and measure total lightning 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 lightning 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 lightning 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 lightning. The GLM owes its heritage to the NASA Lightning 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 lightning activity. Instrument formulation studies begun in January 2006 will be completed in March 2007, with implementation expected to begin in September 2007. Proxy total lightning data from the NASA Lightning 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, Lightning 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 lightning 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

  8. Automated Storm Tracking and the Lightning Jump Algorithm Using GOES-R Geostationary Lightning Mapper (GLM) Proxy Data.

    PubMed

    Schultz, Elise V; Schultz, Christopher J; Carey, Lawrence D; Cecil, Daniel J; Bateman, Monte

    2016-01-01

    This study develops a fully automated lightning jump system encompassing objective storm tracking, Geostationary Lightning Mapper proxy data, and the lightning 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 lightning information (flash rate density). Evaluations showed that the spatial scale of tracked features or storm clusters had a large impact on the lightning 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 lightning 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 lightning jump system.

  9. Automated Storm Tracking and the Lightning Jump Algorithm Using GOES-R Geostationary Lightning Mapper (GLM) Proxy Data

    NASA Technical Reports Server (NTRS)

    Schultz, Elise; Schultz, Christopher Joseph; Carey, Lawrence D.; Cecil, Daniel J.; Bateman, Monte

    2016-01-01

    This study develops a fully automated lightning jump system encompassing objective storm tracking, Geostationary Lightning Mapper proxy data, and the lightning 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 lightning information (flash rate density). Evaluations showed that the spatial scale of tracked features or storm clusters had a large impact on the lightning 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 lightning 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 lightning jump system.

  10. Automated Storm Tracking and the Lightning Jump Algorithm Using GOES-R Geostationary Lightning Mapper (GLM) Proxy Data

    PubMed Central

    SCHULTZ, ELISE V.; SCHULTZ, CHRISTOPHER J.; CAREY, LAWRENCE D.; CECIL, DANIEL J.; BATEMAN, MONTE

    2017-01-01

    This study develops a fully automated lightning jump system encompassing objective storm tracking, Geostationary Lightning Mapper proxy data, and the lightning 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 lightning information (flash rate density). Evaluations showed that the spatial scale of tracked features or storm clusters had a large impact on the lightning 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 lightning 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 lightning jump system. PMID:29303164

  11. First Cloud-to-Ground Lightning Timing Study

    NASA Technical Reports Server (NTRS)

    Huddleston, Lisa L.

    2013-01-01

    NASA's LSP, GSDO and other programs use the probability of cloud-to-ground (CG) lightning occurrence issued by the 45th Weather Squadron (45 WS) in their daily and weekly lightning 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 lightning. These organizations would benefit greatly if the 45 WS could provide more accurate timing of the first CG lightning strike of the day. The Applied Meteorology Unit (AMU) has made significant improvements in forecasting the probability of lightning for the day, but forecasting the time of the first CG lightning 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) lightning 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 lightning 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 lightning activity varies by time of day based on the flow regimes and speed categories, there are extended tails of low lightning activity making it difficult to specify times when the threat of the first lightning flash can be avoided. However, the AMU developed a graphical user interface with input from the 45 WS

  12. Characteristics of Lightning Within Electrified Snowfall Events Using Lightning Mapping Arrays

    NASA Astrophysics Data System (ADS)

    Schultz, Christopher J.; Lang, Timothy J.; Bruning, Eric C.; Calhoun, Kristin M.; Harkema, Sebastian; Curtis, Nathan

    2018-02-01

    This study examined 34 lightning flashes within four separate thundersnow events derived from lightning mapping arrays (LMAs) in northern Alabama, central Oklahoma, and Washington DC. The goals were to characterize the in-cloud component of each lightning flash, as well as the correspondence between the LMA observations and lightning data taken from national lightning networks like the National Lightning 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 lightning 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 lightning flashes, the NLDN detected a return stroke from the cloud back to the tower and not the initial upward leader. This study also discusses lightning's interaction with the human-built environment and provides an example of lightning within heavy snowfall observed by Geostationary Operational Environmental Satellite-16's Geostationary Lightning Mapper.

  13. Characteristics of Lightning within Electrified Snowfall Events using Lightning Mapping Arrays.

    PubMed

    Schultz, Christopher J; Lang, Timothy J; Bruning, Eric C; Calhoun, Kristin M; Harkema, Sebastian; Curtis, Nathan

    2018-02-27

    This study examined 34 lightning flashes within four separate thundersnow events derived from lightning mapping arrays (LMAs) in northern Alabama, central Oklahoma, and Washington DC. The goals were to characterize the in-cloud component of each lightning flash, as well as the correspondence between the LMA observations and lightning data taken from national lightning networks like the National Lightning 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 lightning 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 lightning flashes, the NLDN detected a return stroke from the cloud back to the tower and not the initial upward leader. This study also discusses lightning's interaction with the human built environment and provides an example of lightning within heavy snowfall observed by GOES-16's Geostationary Lightning Mapper.

  14. Trends in Lightning Electrical Energy Derived from the Lightning Imaging Sensor

    NASA Astrophysics Data System (ADS)

    Bitzer, P. M.; Koshak, W. J.

    2016-12-01

    We present results detailing an emerging application of space-based measurement of lightning: the electrical energy. This is a little-used attribute of lightning data which can have applications for severe weather, lightning physics, and wildfires. In particular, we use data from the Tropical Rainfall Measuring Mission Lightning Imaging Sensor (TRMM/LIS) to find the temporal and spatial variations in the detected spectral energy density. This is used to estimate the total lightning 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 lightning, which can provide a baseline for future applications using the Geostationary Lightning Mapper (GLM), the European Lightning Imager (LI), and the International Space Station Lightning Imaging Sensor (ISS/LIS) instruments.

  15. Triggered-Lightning Interaction with a Lightning Protective System: Current Distribution and Electromagnetic Environment

    NASA Technical Reports Server (NTRS)

    Mata, C. T.; Rakov, V. A.; Mata, A. G.

    2010-01-01

    A new comprehensive lightning 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 lightning 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 Lightning Protection System (LPS) of LC39B was built at the International Center for Lightning Research and Testing, Camp Blanding, FL. This scaled down lightning 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 lightning 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.

  16. Lightning and transportation.

    PubMed

    Cherington, M

    1995-12-01

    It is a little-known fact that lightning casualties often involve travel or transportation. López and colleagues, in their studies on the epidemiology of lightning injuries, have reported that 10% of lightning 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 lightning 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 lightning that relate to the danger to people traveling in vehicles, boats, and airplanes. First, I shall deal with lightning 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 lightning protection. Second, I shall consider the matter of lightning strikes to aircraft. In the third section, I shall discuss the question of lightning 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.

  17. Quantification and identification of lightning damage in tropical forests.

    PubMed

    Yanoviak, Stephen P; Gora, Evan M; Burchfield, Jeffrey M; Bitzer, Phillip M; Detto, Matteo

    2017-07-01

    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 lightning kills thousands of trees each year and is an important agent of mortality in some forests, the frequency and distribution of lightning-caused tree death remain unknown for most forests. Moreover, because all evidence regarding the effects of lightning on trees is necessarily anecdotal and post hoc, rigorous tests of hypotheses regarding the ecological effects of lightning are impossible. We developed a combined electronic sensor/camera-based system for the location and characterization of lightning 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 lightning strikes. We used a preliminary version of this system to record and locate 18 lightning strikes to the forest over a 3-year period. Data from field surveys of known lightning strike locations (obtained from the camera system) enabled us to develop a protocol for reliable, ground-based identification of suspected lightning damage to tropical trees. In all cases, lightning 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 lightning 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 lightning-damaged temperate trees were never observed in this study. Given the

  18. Lightning protection of the Fokker 100 CFRP rudder

    NASA Technical Reports Server (NTRS)

    Ruiter, A. J. M.

    1991-01-01

    The construction of the structural parts of the Fokker 100 CFRP rudder is described with respect to the requirements for electrical bonding and lightning protection. Furthermore, the philosophy for the selection of a consumable trailing edge is given. A description of possible alternative designs for trailing edges and their advantages and disadvantages with respect to damage after lightning impact will also be reviewed. An overview of the tests performed on test samples and the rudder construction are presented and discussed. The effectiveness of both the selected structural provisions and trailing edge are described (and proven) by reporting the results of the simulated lightning tests performed. Proof is given that the trailing edge construction and its bonding through the structural parts of the rudder to the main aircraft structure is a solution which results in minor damage to the rudder after lightning impact. Furthermore, it is shown that the selected trailing edge construction is less favored by the structural designers due to the weight penalty.

  19. Correlated observations of three triggered lightning flashes

    NASA Technical Reports Server (NTRS)

    Idone, V. P.; Orville, R. E.; Hubert, P.; Barret, L.; Eybert-Berard, A.

    1984-01-01

    Three triggered lightning flashes, initiated during the Thunderstorm Research International Program (1981) at Langmuir Laboratory, 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 lightning data do not concur with the weak positive correlation between dart leader propagation speed and interstroke interval. Therefore, application of triggered lightning results to natural lightning 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.

  20. Grounding and lightning protection. Volume 5

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

    Robinson, M.D.

    1987-12-31

    Grounding systems protect personnel and equipment by isolating faulted systems and dissipating transient currents. Lightning protection systems minimize the possible consequences of a direct strike by lightning. This volume focuses on design requirements of the grounding system and on present-day concepts used in the design of lightning 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. Lightning protection systems are installed on tall structures (such asmore » chimneys and cooling towers) to minimize the possibility of structural damage caused by direct lightning strokes. These strokes may carry currents of 200,000 A or more. The volume examines the formation and characteristics of lightning strokes and the way stroke characteristics influence the design of lightning 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

  1. Structural Analysis of Lightning Protection System for New Launch Vehicle

    NASA Technical Reports Server (NTRS)

    Cope, Anne; Moore, Steve; Pruss, Richard

    2008-01-01

    This project includes the design and specification of a lightning protection system for Launch Complex 39 B (LC39B) at Kennedy Space Center, FL in support of the Constellation Program. The purpose of the lightning protection system is to protect the Crew Launch Vehicle (CLV) or Cargo Launch Vehicle (CaLV) and associated launch equipment from direct lightning strikes during launch processing and other activities prior to flight. The design includes a three-tower, overhead catenary wire system to protect the vehicle and equipment on LC39B as described in the study that preceded this design effort: KSC-DX-8234 "Study: Construct Lightning Protection System LC3 9B". The study was a collaborative effort between Reynolds, Smith, and Hills (RS&H) and ASRC Aerospace (ASRC), where ASRC was responsible for the theoretical design and risk analysis of the lightning protection system and RS&H was responsible for the development of the civil and structural components; the mechanical systems; the electrical and grounding systems; and the siting of the lightning protection system. The study determined that a triangular network of overhead catenary cables and down conductors supported by three triangular free-standing towers approximately 594 ft tall (each equipped with a man lift, ladder, electrical systems, and communications systems) would provide a level of lightning protection for the Constellation Program CLV and CaLV on Launch Pad 39B that exceeds the design requirements.

  2. Investigating lightning-to-ionosphere energy coupling based on VLF lightning propagation characterization

    NASA Astrophysics Data System (ADS)

    Lay, Erin Hoffmann

    In this dissertation, the capabilities of the World-Wide Lightning Location Network (WWLLN) are analyzed in order to study the interactions of lightning energy with the lower ionosphere. WWLLN is the first global ground-based lightning location network and the first lightning detection network that continuously monitors lightning 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 lightning and transient luminous events. This dissertation characterizes the World-Wide Location Network (WWLLN) in terms of detection efficiency, location and timing accuracy, and lightning 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 lightning counts based on location. These normalized global lightning 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 lightning stroke radiated energy in the 1-24 kHz frequency range by a global lightning detection network. These characterizations and improvements to WWLLN are motivated by the desire to use WWLLN data to address the problem of lightning-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 lightning electromagnetic pulses (EMP) on the ionosphere by accumulating electron density changes resulting

  3. New Mission to Measure Global Lightning from the International Space Station (ISS)

    NASA Astrophysics Data System (ADS)

    Blakeslee, R. J.; Christian, H. J., Jr.; Mach, D. M.; Buechler, D. E.; Koshak, W. J.; Walker, T. D.; Bateman, M. G.; Stewart, M. F.; O'Brien, S.; Wilson, T. O.; Pavelitz, S. D.; Coker, C.

    2015-12-01

    Over the past 20 years, the NASA Marshall Space Flight Center, the University of Alabama in Huntsville, and their partners developed and demonstrated the effectiveness and value of space-based lightning observations as a remote sensing tool for Earth science research and applications, and, in the process, established a robust global lightning climatology. The observations included measurements from the Lightning Imaging Sensor (LIS) on the Tropical Rainfall Measuring Mission (TRMM) that acquired global observations of total lightning (i.e., intracloud and cloud-to-ground discharges) from November 1997 to April 2015 between 38° N/S latitudes, and its Optical Transient Detector predecessor that acquired observation from May 1995 to April 2000 over 75° N/S latitudes. In February 2016, as an exciting follow-on to these prior missions, a space-qualified LIS built as a flight-spare for TRMM will be delivered to the International Space Station (ISS) for a 2 year or longer mission, flown as a hosted payload on the Department of Defense Space Test Program-Houston 5 (STP-H5) mission. The LIS on ISS will continue observations of the amount, rate, and radiant energy of total lightning over the Earth. More specifically, LIS measures lightning during both day and night, with storm scale resolution (~4 km), millisecond timing, and high, uniform detection efficiency, without any land-ocean bias. Lightning is a direct and most impressive response to intense atmospheric convection. ISS LIS lightning observations will continue to provide important gap-filling inputs to pressing Earth system science issues across a broad range of disciplines. This mission will also extend TRMM time series observations, expand the latitudinal coverage to 54° latitude, provide real-time lightning data to operational users, espically over data sparse oceanic regions, and enable cross-sensor observations and calibrations that includes the new GOES-R Geostationary Lightning Mapper (GLM) and the Meteosat

  4. Developing an Enhanced Lightning Jump Algorithm for Operational Use

    NASA Technical Reports Server (NTRS)

    Schultz, Christopher J.; Petersen, Walter A.; Carey, Lawrence D.

    2009-01-01

    Overall Goals: 1. Build on the lightning jump framework set through previous studies. 2. Understand what typically occurs in nonsevere convection with respect to increases in lightning. 3. Ultimately develop a lightning jump algorithm for use on the Geostationary Lightning Mapper (GLM). 4 Lightning 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%.

  5. Infrasound from lightning measured in Ivory Coast

    NASA Astrophysics Data System (ADS)

    Farges, T.; Matoza, R. S.

    2011-12-01

    It is well established that more than 2,000 thunderstorms occur continuously around the world and that about 45 lightning 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 lightning flashes, ...). Some of the IMS stations are located where worldwide lightning detection networks (e.g. WWLLN) have a weak detection capability but lightning activity is high (e.g. Africa, South America). These infrasound stations are well localised to study lightning 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 lightning studies possible. For example, Farges and Blanc (2010) show clearly that it is possible to measure lightning infrasound from thunderstorms within a range of distances from the infrasound station. Infrasound from lightning 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 lightning flashes can be detected with this technique, giving better results locally than worldwide lightning 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 lightning activity and its temporal variation. First statistical results will be presented in this paper based on 3 years of data (2005-2008).

  6. Lightning Strike Induced Damage Mechanisms of Carbon Fiber Composites

    NASA Astrophysics Data System (ADS)

    Kawakami, Hirohide

    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 lightning has been rising. Main task of this study is to clarify the lightning damage mechanism of carbon fiber reinforced epoxy polymer composites to help further development of lightning strike protection. The research on lightning 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 lightning strike in a laboratory. 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 lightning intensity, and lightning current waveforms. It revealed that the thermal resistance capability of polymer matrix was one of the most influential parameters on lightning damage resistance of CFRPs. Based on the experimental findings, the semi-empirical analysis model for predicting the extent of lightning 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 lightning tests were performed to explore more practical situations. Specifically, filled-hole CFRP plates and patch

  7. The 1984 direct strike lightning data, part 3

    NASA Technical Reports Server (NTRS)

    Thomas, Mitchel E.; Carney, Harold K.

    1986-01-01

    Data waveforms are presented which were obtained during the 1984 direct-strike lightning tests utilizing the NASA F106-B aircraft specially instrumented for lightning 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 lightning. This is part 3, consisting entirely of charts and graphs.

  8. Development and implementation of a propeller test capability for GL-10 "Greased Lightning" propeller design

    NASA Astrophysics Data System (ADS)

    Duvall, Brian Edward

    Interest in small unmanned aerial vehicles has increased dramatically in recent years. Hybrid vehicles which allow forward flight as a fixed wing aircraft and a true vertical landing capability have always had applications. Management of the available energy and noise associated with electric propeller propulsion systems presents many challenges. NASA Langley has developed the Greased Lightning 10 (GL-10) vertical takeoff, unmanned aerial vehicle with ten individual motors and propellers. All are used for propulsion during takeoff and contribute to acoustic noise pollution which is an identified nuisance to the surrounding users. A propeller test capability was developed to gain an understanding of how the noise can be reduced while meeting minimum thrust requirements. The designed propeller test stand allowed for various commercially available propellers to be tested for potential direct replacement of the current GL-10 propellers and also supported testing of a newly designed propeller provided by the Georgia Institute of Technology. Results from the test program provided insight as to which factors affect the noise as well as performance characteristics. The outcome of the research effort showed that the current GL-10 propeller still represents the best choice of all the candidate propellers tested.

  9. Narrow-band filters for the lightning imager

    NASA Astrophysics Data System (ADS)

    Piegari, Angela; Di Sarcina, Ilaria; Grilli, Maria Luisa; Menchini, Francesca; Scaglione, Salvatore; Sytchkova, Anna; Zola, Danilo; Cuevas, Leticia P.

    2017-11-01

    The study of lightning phenomena will be carried out by a dedicated instrument, the lightning imager, that will make use of narrow-band transmission filters for separating the Oxygen emission lines in the clouds, from the background signal. The design, manufacturing and testing of these optical filters will be described here.

  10. Aircraft Lightning Electromagnetic Environment Measurement

    NASA Technical Reports Server (NTRS)

    Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.

    2011-01-01

    This paper outlines a NASA project plan for demonstrating a prototype lightning 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 lightning 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 lightning (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 lightning 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.

  11. Lightning Physics and Effects

    NASA Astrophysics Data System (ADS)

    Orville, Richard E.

    2004-03-01

    Lightning Physics and Effects is not a lightning book; it is a lightning 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 lightning, including lightning physics, lightning protection, and the interaction of lightning 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 lightning 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.

  12. Electrical Characterizations of Lightning Strike Protection Techniques for Composite Materials

    NASA Technical Reports Server (NTRS)

    Szatkowski, George N.; Nguyen, Truong X.; Koppen, Sandra V.; Ely, Jay J.; Mielnik, John J.

    2009-01-01

    The growing application of composite materials in commercial aircraft manufacturing has significantly increased the risk of aircraft damage from lightning strikes. Composite aircraft designs require new mitigation strategies and engineering practices to maintain the same level of safety and protection as achieved by conductive aluminum skinned aircraft. Researchers working under the NASA Aviation Safety Program s Integrated Vehicle Health Management (IVHM) Project are investigating lightning damage on composite materials to support the development of new mitigation, diagnosis & prognosis techniques to overcome the increased challenges associated with lightning protection on composite aircraft. This paper provides an overview of the electrical characterizations being performed to support IVHM lightning damage diagnosis research on composite materials at the NASA Langley Research Center.

  13. Lightning Burns and Electrical Trauma in a Couple Simultaneously Struck by Lightning

    PubMed Central

    Eyerly-Webb, Stephanie A.; Solomon, Rachele; Lee, Seong K.; Sanchez, Rafael; Carrillo, Eddy H.; Davare, Dafney L.; Kiffin, Chauniqua; Rosenthal, Andrew

    2017-01-01

    More people are struck and killed by lightning each year in Florida than any other state in the United States. This report discusses a couple that was simultaneously struck by lightning while walking arm-in-arm. Both patients presented with characteristic lightning burns and were admitted for hemodynamic monitoring, serum labs, and observation and were subsequently discharged home. Despite the superficial appearance of lightning burns, serious internal electrical injuries are common. Therefore, lightning strike victims should be admitted and evaluated for cardiac arrhythmias, renal injury, and neurological sequelae.

  14. Lightning protection design external tank /Space Shuttle/

    NASA Technical Reports Server (NTRS)

    Anderson, A.; Mumme, E.

    1979-01-01

    The possibility of lightning striking the Space Shuttle during liftoff is considered and the lightning 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 lightning strike to an area of the spacecraft which can sustain the strike. The ET lightning 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 lightning protection system design is shown to be comprised of the following: (1) a lightning 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.

  15. How Lightning Works Inside Thunderstorms: A Half-Century of Lightning Studies

    NASA Astrophysics Data System (ADS)

    Krehbiel, P. R.

    2015-12-01

    Lightning is a fascinating and intriguing natural phenomenon, but the most interesting parts of lightning 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 lightning produces prodigious RF emissions, has allowed us to image and study lightning 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 lightning 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, lightning 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 lightning 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 lightning in normally- and anomalously electrified storms. A particularly important aspect of the investigations has been comparative studies of lightning in different climatological regimes. We conclude with observations being obtained by a high-speed broadband VHF interferometer, which show in unprecedented detail how individual lightning discharges develop inside storms. From combined interferometer and 3-D mapping data, we are beginning to unlock nature's secrets

  16. Lightning Instrumentation at KSC

    NASA Technical Reports Server (NTRS)

    Colon, Jose L.; Eng, D.

    2003-01-01

    This report summarizes lightning phenomena with a brief explanation of lightning generation and lightning activity as related to KSC. An analysis of the instrumentation used at launching Pads 39 A&B for measurements of lightning 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 lightning current information from several sensors using only one high speed recording channel while monitoring all sensors to replace the actual manual lightning current recorders and a novel device for the protection system are described.

  17. A Comparison of Lightning Flashes as Observed by the Lightning Imaging Sensor and the North Alabama Lightning Mapping Array

    NASA Technical Reports Server (NTRS)

    Bateman, M. G.; Mach, D. M.; McCaul, M. G.; Bailey, J. C.; Christian, H. J.

    2008-01-01

    The Lightning Imaging Sensor (LIS) aboard the TRMM satellite has been collecting optical lightning data since November 1997. A Lightning Mapping Array (LMA) that senses VHF impulses from lightning 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 lightning 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 Lightning Mapper (GLM) on GOES-R, better understanding and ground truth of each of these instruments and their respective flash algorithms is needed.

  18. The physics of lightning

    NASA Astrophysics Data System (ADS)

    Dwyer, Joseph R.; Uman, Martin A.

    2014-01-01

    Despite being one of the most familiar and widely recognized natural phenomena, lightning remains relatively poorly understood. Even the most basic questions of how lightning is initiated inside thunderclouds and how it then propagates for many tens of kilometers have only begun to be addressed. In the past, progress was hampered by the unpredictable and transient nature of lightning and the difficulties in making direct measurements inside thunderstorms, but advances in instrumentation, remote sensing methods, and rocket-triggered lightning experiments are now providing new insights into the physics of lightning. Furthermore, the recent discoveries of intense bursts of X-rays and gamma-rays associated with thunderstorms and lightning illustrate that new and interesting physics is still being discovered in our atmosphere. The study of lightning and related phenomena involves the synthesis of many branches of physics, from atmospheric physics to plasma physics to quantum electrodynamics, and provides a plethora of challenging unsolved problems. In this review, we provide an introduction to the physics of lightning with the goal of providing interested researchers a useful resource for starting work in this fascinating field. By what physical mechanism or mechanisms is lightning initiated in the thundercloud? What is the maximum cloud electric field magnitude and over what volume of the cloud? What, if any, high energy processes (runaway electrons, X-rays, gamma rays) are involved in lightning initiation and how? What is the role of various forms of ice and water in lightning initiation? What physical mechanisms govern the propagation of the different types of lightning leaders (negative stepped, first positive, negative dart, negative dart-stepped, negative dart-chaotic) between cloud and ground and the leaders inside the cloud? What is the physical mechanism of leader attachment to elevated objects on the ground and to the flat ground? What are the characteristics

  19. NASA thunderstorm overflight program: Atmospheric electricity research. An overview report on the optical lightning detection experiment for spring and summer 1983

    NASA Technical Reports Server (NTRS)

    Vaughan, O. H., Jr.

    1984-01-01

    This report presents an overview of the NASA Thunderstorm Overflight Program (TOP)/Optical Lightning Experiment (OLDE) being conducted by the Marshall Space Flight Center and university researchers in atmospheric electricity. Discussed in this report are the various instruments flown on the NASA U-2 aircraft, as well as the ground instrumentation used in 1983 to collect optical and electronic signatures from the lightning events. Samples of some of the photographic and electronic signatures are presented. Approximately 4132 electronic data samples of optical pulses were collected and are being analyzed by the NASA and university researchers. A number of research reports are being prepared for future publication. These reports will provide more detailed data analysis and results from the 1983 spring and summer program.

  20. Epidemiology of electrical and lightning-related injuries among Canadian children and youth, 1997-2010: A Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP) study.

    PubMed

    Böhrer, Madeleine; Stewart, Samuel A; Hurley, Katrina F

    2017-06-27

    Introduction Although death due to electrical injury and lightning are rare in children, these injuries are often preventable. Twenty years ago, most injuries occurred at home, precipitated by oral contact with electrical cords, contact with wall sockets and faulty electrical equipment. We sought to assess the epidemiology of electrical injuries in children presenting to Emergency Departments (EDs) that participate in the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP). This study is a retrospective review of electrical and lightning injury data from CHIRPP. The study population included children and youth aged 0-19 presenting to participating CHIRPP EDs from 1997-2010. Age, sex, year, setting, circumstance and disposition were extracted. Variables were tested using Fisher's exact test and simple linear regression. The dataset included 1183 electrical injuries, with 84 (7%) resulting in hospitalization. Most events occurred at home in the 2-5 year age group and affected the hands. Since 1997 there has been a gradual decrease in the number of electrical injuries per year (p<0.01) and there is an annual surge in electrical injuries over the summer (p<0.01). Forty-six percent of injuries involved electrical outlets, 65% of injuries involved some sort of electrical equipment. Injuries due to lightning were rare (n=19). No deaths were recorded in the database. Despite the decrease in the number of electrical injuries per year, a large portion of injuries still appear to be preventable. Further research should focus on effective injury prevention strategies.

  1. Measurement of characteristics of lightning at high altitudes

    NASA Technical Reports Server (NTRS)

    Coquelet, M.; Gall, D.

    1981-01-01

    New development in aeronautical technology -- the use of composite materials, new electronic components, electric flight controls -- have made aircraft potentially more and more vulnerable to the effects of lightning. In-flight tests were conducted to evaluate the current in a bolt of lightning, to measure voltage surge in the onboard circuitry and in certain pieces of equipment, and to document the relationship lightning bolt current and the voltage surge so as to develop a theoretical model and thuds to become acquainted with the significant

  2. Lightning Physics: A Three Year Program

    DTIC Science & Technology

    1983-01-01

    because these aircraft are controlled poeal’ r r o(z’, I- RIC) with low-voltage digital electronics and are in part construct- 4w J(,3 cR "*t • at ed of... millise - limits pretrigger and delayed-trigger mode,. and a variety of sample conds, and hundreds of microseconds, respectively, the time of simple...processes, but we feel it prudent to discontinue use of the Proctor, D. E., A radio study of lightning, Ph.D. thesis , Univ. of designations in order

  3. A NASA Lightning Parameterization for CMAQ

    NASA Technical Reports Server (NTRS)

    Koshak, William; Khan, Maudood; Biazar, Arastoo; Newchurch, Mike; McNider, Richard

    2009-01-01

    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, lightning modeling for CMAQ is highly oversimplified. This leads to very poor estimates of lightning-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 lightning 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 lightning model, called the Lightning Nitrogen Oxides Model (LNOM) that combines state-of-the-art lightning measurements, empirical results from field studies, and beneficial laboratory results to arrive at a realistic representation of lightning NOx production for CMAQ. NASA satellite lightning data is used in conjunction with ground-based lightning detection systems to assure that the best representation of lightning frequency, geographic location, channel length, channel altitude, strength (i.e., channel peak current), and

  4. Struck-by-lightning deaths in the United States.

    PubMed

    Adekoya, Nelson; Nolte, Kurt B

    2005-05-01

    The objective of the research reported here was to examine the epidemiologic characteristics of struck-by-lightning 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 lightning-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 lightning-related deaths were contributed by the New Mexico Office of the Medical Investigator. It was found that a total of 374 struck-by-lightning 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 lightning deaths were highest in Florida (49 deaths) and Texas (32 deaths). A total of 129 work-related lightning 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 lightning 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-lightning deaths were from the South and the Midwest, and during 1995-2002, one of every four struck-by-lightning 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

  5. Spatio-temporal dimension of lightning flashes based on three-dimensional Lightning Mapping Array

    NASA Astrophysics Data System (ADS)

    López, Jesús A.; Pineda, Nicolau; Montanyà, Joan; Velde, Oscar van der; Fabró, Ferran; Romero, David

    2017-11-01

    3D mapping system like the LMA - Lightning Mapping Array - are a leap forward in lightning observation. LMA measurements has lead to an improvement on the analysis of the fine structure of lightning, allowing to characterize the duration and maximum extension of the cloud fraction of a lightning 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 lightning flash. The "Ebro Lightning 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 lightning flashes including both summer and winter events. Results show an average lightning 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 lightning lengths were about ± 1.2 km and ± 0.7 km for the mean and median values respectively. In case of winter lightning, 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 lightning lengths calculated through this correlative method was approximately 17 km for both seasons. On the other hand, the highest median ratios of lightning length to CG discharges in both summer and winter were reported for positive CG discharges.

  6. Situational Lightning Climatologies

    NASA Technical Reports Server (NTRS)

    Bauman, William; Crawford, Winifred

    2010-01-01

    Research has revealed distinct spatial and temporal distributions of lightning 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 lightning 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 lightning strike data to improve the accuracy of the climatologies. The software determines the location of each CG lightning strike with 5-, 10-, 20-, and 30-nmi (.9.3-, 18.5-, 37-, 55.6-km) radii from each airfield. Each CG lightning strike is binned at 1-, 3-, and 6-hour intervals at each specified radius. The software merges the CG lightning 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.

  7. Lightning burns.

    PubMed

    Russell, Katie W; Cochran, Amalia L; Mehta, Sagar T; Morris, Stephen E; McDevitt, Marion C

    2014-01-01

    We present the case of a lightning-strike victim. This case illustrates the importance of in-field care, appropriate referral to a burn center, and the tendency of lightning burns to progress to full-thickness injury.

  8. GOES-R Geostationary Lightning Mapper Performance Specifications and Algorithms

    NASA Technical Reports Server (NTRS)

    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.

    2008-01-01

    The Geostationary Lightning Mapper (GLM) is a single channel, near-IR imager/optical transient event detector, used to detect, locate and measure total lightning 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 lightning. The mission objectives for the GLM are to: (1) Provide continuous, full-disk lightning 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 lightning. The GLM owes its heritage to the NASA Lightning 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 lightning activity. GOES-R Risk Reduction Team and Algorithm Working Group Lightning Applications Team have begun to develop the Level 2 algorithms and applications. The science data will consist of lightning "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 lightning data from the NASA Lightning Imaging Sensor on the Tropical Rainfall Measuring Mission (TRMM) satellite and regional test beds (e.g., Lightning 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.

  9. Recent Advancements in Lightning Jump Algorithm Work

    NASA Technical Reports Server (NTRS)

    Schultz, Christopher J.; Petersen, Walter A.; Carey, Lawrence D.

    2010-01-01

    In the past year, the primary objectives were to show the usefulness of total lightning as compared to traditional cloud-to-ground (CG) networks, test the lightning 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 lightning 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 lightning jump algorithm configuration holds the most promise in terms of prospective operational lightning 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 lightning jump algorithms, accurate thunderstorm cell tracking work must be undertaken to track lightning 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 lightning jump algorithm, because of the suppressed vertical depth impact on overall flash counts (i.e., a relative dearth in lightning). 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).

  10. The 1981 direct strike lightning data. [utilizing the F-106 aircraft

    NASA Technical Reports Server (NTRS)

    Pitts, F. L.; Thomas, M. E.

    1982-01-01

    Data waveforms obtained during the 1981 direct strike lightning tests, utilizing the NASA F-106B aircraft specially instrumented for lightning electromagnetic measurements are presented. The aircraft was operated in a thunderstorm environment to elicit strikes. Electromagnetic field data were recorded for both attached lightning and free field excitation of the aircraft.

  11. Analysis of ELF Radio Atmospherics Radiated by Rocket-Triggered Lightning

    NASA Astrophysics Data System (ADS)

    Dupree, N. A.; Moore, R. C.; Pilkey, J. T.; Uman, M. A.; Jordan, D. M.; Caicedo, J. A.; Hare, B.; Ngin, T. K.

    2014-12-01

    Experimental observations of ELF radio atmospherics produced by rocket-triggered lightning flashes are used to analyze Earth-ionosphere waveguide excitation and propagation characteristics. Rocket-triggered lightning experiments are performed at the International Center for Lightning Research and Testing (ICLRT) located at Camp Blanding, Florida. Long-distance ELF observations are performed in California, Greenland, and Antarctica. The lightning current waveforms directly measured at the base of the lightning channel (at the ICLRT) along with pertinent Lightning 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 lightning.

  12. Lightning Imaging Sensor (LIS) on the International Space Station (ISS): Launch, Installation, Activation and First Results

    NASA Technical Reports Server (NTRS)

    Blakeslee, R. J.; Christian, H. J.; Mach, D. M.; Buechler, D. E.; Wharton, N. A.; Stewart, M. F.; Ellett, W. T.; Koshak, W. J.; Walker, T. D.; Virts, K.; hide

    2017-01-01

    Mission: Fly a flight-spare LIS (Lightning Imaging Sensor) on ISS to take advantage of unique capabilities provided by the ISS (e.g., high inclination, real time data); Integrate LIS as a hosted payload on the DoD Space Test Program-Houston 5 (STP-H5) mission and launch on a Space X rocket for a minimum 2 year mission. Measurement: NASA and its partners developed and demonstrated effectiveness and value of using space-based lightning observations as a remote sensing tool; LIS measures lightning (amount, rate, radiant energy) with storm scale resolution, millisecond timing, and high detection efficiency, with no land-ocean bias. Benefit: LIS on ISS will extend TRMM (Tropical Rainfall Measuring Mission) time series observations, expand latitudinal coverage, provide real time data to operational users, and enable cross-sensor calibration.

  13. Geostationary Lightning Mapper for GOES-R and Beyond

    NASA Technical Reports Server (NTRS)

    Goodman, Steven J.; Blakeslee, R. J.; Koshak, W.

    2008-01-01

    The Geostationary Lightning Mapper (GLM) is a single channel, near-IR imager/optical transient event detector, used to detect, locate and measure total lightning 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 lightning 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 lightning 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 lightning. The GLM owes its heritage to the NASA Lightning 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 lightning 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 Lightning Applications Team have begun to develop the Level 2 algorithms and applications. Proxy total lightning data from the NASA Lightning Imaging Sensor on the Tropical Rainfall Measuring Mission (TRMM) satellite and regional test beds (e.g., Lightning 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 lightning mapping data are being provided in an experimental mode to selected National Weather Service (NWS

  14. Lightning Safety Tips and Resources

    MedlinePlus

    ... Safety Brochure U.S. Lightning Deaths in 2018 : 5 Youtube: Lightning Safety for the Deaf and Hard of ... for Hard of Hearing: jpg , high res png YouTube: Lightning Safety Tips Lightning Safety When Working Outdoors : ...

  15. MSFC shuttle lightning research

    NASA Technical Reports Server (NTRS)

    Vaughan, Otha H., Jr.

    1993-01-01

    The shuttle mesoscale lightning 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 lightning characteristics and to create a data base for use in demonstrating observation simulations for future spaceborne lightning mapping systems. These flights are also providing design criteria data for the design of a proposed shuttle MLE-type lightning research instrument called mesoscale lightning observational sensors (MELOS), which are currently under development here at MSFC.

  16. Lightning Imaging Sensor (LIS) for the International Space Station (ISS): Mission Description and Science Goals

    NASA Technical Reports Server (NTRS)

    Blakeslee, R. J.; Christian, H. J.; Stewart, M. F.; Mach, D. M.; Buechler, D. E.; Koshak, W. J.

    2014-01-01

    In recent years, NASA Marshall Space Flight Center, the University of Alabama in Huntsville, and their partners have developed and demonstrated space-based lightning observations as an effective remote sensing tool for Earth science research and applications. The Lightning Imaging Sensor (LIS) on the Tropical Rainfall Measuring Mission (TRMM) continues to provide global observations of total lightning after 17 years on-orbit. In April 2013, a space-qualified LIS built as the flight spare for TRMM, was selected for flight as a science mission on the International Space Station. The ISS LIS (or I-LIS as Hugh Christian prefers) will be flown as a hosted payload on the Department of Defense Space Test Program (STP) H5 mission, which has a January 2016 baseline launch date aboard a SpaceX launch vehicle for a 2-4 year or longer mission. The LIS measures the amount, rate, and radiant energy of global lightning. More specifically, it measures lightning during both day and night, with storm scale resolution, millisecond timing, and high, uniform detection efficiency, without any land-ocean bias. Lightning is a direct and most impressive response to intense atmospheric convection. It has been found that the characteristics of lightning that LIS measures can be quantitatively coupled to both thunderstorm and other geophysical processes. Therefore, the ISS LIS lightning observations will provide important gap-filling inputs to pressing Earth system science issues across a broad range of disciplines, including weather, climate, atmospheric chemistry, and lightning physics. A unique contribution from the ISS platform will be the availability of real-time lightning, especially valuable for operational applications over data sparse regions such as the oceans. The ISS platform will also uniquely enable LIS to provide simultaneous and complementary observations with other payloads such as the European Space Agency's Atmosphere-Space Interaction Monitor (ASIM) that will be exploring

  17. Artificial Neural Network applied to lightning flashes

    NASA Astrophysics Data System (ADS)

    Gin, R. B.; Guedes, D.; Bianchi, R.

    2013-05-01

    The development of video cameras enabled cientists to study lightning discharges comportment with more precision. The main goal of this project is to create a system able to detect images of lightning discharges stored in videos and classify them using an Artificial Neural Network (ANN)using C Language and OpenCV libraries. The developed system, can be split in two different modules: detection module and classification module. The detection module uses OpenCV`s computer vision libraries and image processing techniques to detect if there are significant differences between frames in a sequence, indicating that something, still not classified, occurred. Whenever there is a significant difference between two consecutive frames, two main algorithms are used to analyze the frame image: brightness and shape algorithms. These algorithms detect both shape and brightness of the event, removing irrelevant events like birds, as well as detecting the relevant events exact position, allowing the system to track it over time. The classification module uses a neural network to classify the relevant events as horizontal or vertical lightning, save the event`s images and calculates his number of discharges. The Neural Network was implemented using the backpropagation algorithm, and was trained with 42 training images , containing 57 lightning events (one image can have more than one lightning). TheANN was tested with one to five hidden layers, with up to 50 neurons each. The best configuration achieved a success rate of 95%, with one layer containing 20 neurons (33 test images with 42 events were used in this phase). This configuration was implemented in the developed system to analyze 20 video files, containing 63 lightning discharges previously manually detected. Results showed that all the lightning discharges were detected, many irrelevant events were unconsidered, and the event's number of discharges was correctly computed. The neural network used in this project achieved a

  18. Plotting Lightning-Stroke Data

    NASA Technical Reports Server (NTRS)

    Tatom, F. B.; Garst, R. A.

    1986-01-01

    Data on lightning-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 lightning strokes in each cell tabulated, and value representing density of lightning strokes assigned to each cell. With contour-plotting routine, computer draws contours of lightning-stroke density for region. Shapes of contours compared directly with shapes of storm cells.

  19. Infrasound from lightning measured in Ivory Coast

    NASA Astrophysics Data System (ADS)

    Farges, T.; Millet, C.; Matoza, R. S.

    2012-04-01

    It is well established that more than 2,000 thunderstorms occur continuously around the world and that about 45 lightning 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 lightning flashes, …). Some of the IMS stations are located where worldwide lightning detection networks (e.g. WWLLN) have a weak detection capability but lightning activity is high (e.g. Africa, South America). These infrasound stations are well localised to study lightning 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 lightning studies possible. For example, Farges and Blanc (2010) show clearly that it is possible to measure lightning infrasound from thunderstorms within a range of distances from the infrasound station. Infrasound from lightning 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 lightning flashes can be detected with this technique, giving better results locally than worldwide lightning detection networks. An IMS infrasound station has been installed in Ivory Coast for 9 years. The lightning 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 lightning activity and its temporal variation. First statistical results will be presented in this paper based on 4 years of data (2005-2009). For short lightning distances (less than 20 km), up to 60 % of lightning detected by WWLLN has been one-to-one correlated

  20. The North Alabama Lightning Warning Product

    NASA Technical Reports Server (NTRS)

    Buechler, Dennis E.; Blakeslee, R. J.; Stano, G. T.

    2009-01-01

    The North Alabama Lightning Mapping Array NALMA has been collecting total lightning 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 lightning product used by the offices is the lightning source density plot. The new product provides a probabalistic, short-term, graphical forecast of the probability of lightning activity occurring at 5 min intervals over the next 30 minutes . One of the uses of the current lightning 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 lightning is occurring. This product quantifies that observation. The Lightning Warning Product is derived from total lightning observations from the Washington, D.C. (DCLMA) and North Alabama Lightning Mapping Arrays and cloud-to-ground lightning flashes detected by the National Lightning 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 lightning source density product.

  1. Expanding the Operational Use of Total Lightning Ahead of GOES-R

    NASA Technical Reports Server (NTRS)

    Stano, Geoffrey T.; Wood, Lance; Garner, Tim; Nunez, Roland; Kann, Deirdre; Reynolds, James; Rydell, Nezette; Cox, Rob; Bobb, William R.

    2015-01-01

    NASA's Short-term Prediction Research and Transition Center (SPoRT) has been transitioning real-time total lightning observations from ground-based lightning mapping arrays since 2003. This initial effort was with the local Weather Forecast Offices (WFO) that could use the North Alabama Lightning Mapping Array (NALMA). These early collaborations established a strong interest in the use of total lightning for WFO operations. In particular the focus started with warning decision support, but has since expanded to include impact-based decision support and lightning safety. SPoRT has used its experience to establish connections with new lightning 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 lightning 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) lightning 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 lightning, setting the stage for a real-time assessment during May-July 2014. With five lightning mapping arrays covering multiple geographic locations, the 2014 assessment has demonstrated numerous uses of total lightning in varying situations. Several highlights include a much broader use of total lightning 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 lightning, demonstrating how these data can support air traffic management, particularly in the Terminal Radar Approach

  2. Infrasound Observations from Lightning

    NASA Astrophysics Data System (ADS)

    Arechiga, R. O.; Johnson, J. B.; Edens, H. E.; Thomas, R. J.; Jones, K. R.

    2008-12-01

    To provide additional insight into the nature of lightning, 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 lightning. Hyperbolic formulations of time of arrival (TOA) measurements and interferometric techniques were used to locate lightning sources occurring over and outside the network. A comparative analysis of simultaneous Lightning 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 lightning flashes in three spatial dimensions and time, operating in the 60 - 66 MHz television band. The comparison showed strong evidence that lightning 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 lightning processes.

  3. Lightning attachment patterns and flight conditions for storm hazards, 1980

    NASA Technical Reports Server (NTRS)

    Fisher, B. D.; Keyser, G. L., Jr.; Deal, P. L.

    1982-01-01

    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 lightning data and the associated flight conditions. Ground based weather radar measurements in conjunction with these penetrations were made by NOAA National Severe Storms Laboratory in Oklahoma and by NASA Wallops Flight Center in Virginia. In 1980, the airplane received 10 direct lightning strikes; in addition, lightning transient data were recorded from 6 nearby flashes. Following each flight, the airplane was thoroughly inspected for evidence of lightning attachment, and the individual lightning 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 lightning 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.

  4. A Lightning Safety Primer for Camps.

    ERIC Educational Resources Information Center

    Attarian, Aram

    1992-01-01

    Provides the following information about lightning, which is necessary for camp administrators and staff: (1) warning signs of lightning; (2) dangers of lightning; (3) types of lightning injuries; (4) prevention of lightning injury; and (5) helpful training tips. (KS)

  5. Multivariate Statistical Inference of Lightning Occurrence, and Using Lightning Observations

    NASA Technical Reports Server (NTRS)

    Boccippio, Dennis

    2004-01-01

    Two classes of multivariate statistical inference using TRMM Lightning 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 lightning/no-lightning classifiers can be quite high, over land (above 80% Probability of Detection; below 20% False Alarm Rate). In the second, passive microwave and lightning 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 lightning observations.

  6. Evidence for lightning on Venus

    NASA Technical Reports Server (NTRS)

    Strangeway, R. J.

    1992-01-01

    Lightning is an interesting phenomenon both for atmospheric and ionospheric science. At the Earth lightning is generated in regions where there is strong convection. Lightning also requires the generation of large charge-separation electric fields. The energy dissipated in a lightning discharge can, for example, result in chemical reactions that would not normally occur. From an ionospheric point of view, lightning 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 lightning at Venus has important consequences for our knowledge of why lightning occurs and how the energy is dissipated in the atmosphere and ionosphere. As discussed here, it now appears that lightning occurs in the dusk local time sector at Venus.

  7. Lightning swept-stroke attachment patterns and flight conditions for storm hazards 1981

    NASA Technical Reports Server (NTRS)

    Fisher, B. D.

    1984-01-01

    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 lightning data and the associated flight conditions. Ground-based weather radar measurements in conjunction with these penetrations were made by NOAA National Severe Storms Laboratory in Oklahoma and by NASA Wallops Flight Facility in Virginia. In 1981, the airplane received 10 direct lightning strikes; in addition, lightning transient data were recorded from 22 nearby flashes. Following each flight, the airplane was thoroughly inspected for evidence of lightning attachment, and the individual lightning 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 lightning 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.

  8. 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.

  9. Performance Study of Earth Networks Total Lightning Network using Rocket-Triggered Lightning Data in 2014

    NASA Astrophysics Data System (ADS)

    Heckman, S.

    2015-12-01

    Modern lightning locating systems (LLS) provide real-time monitoring and early warning of lightningactivities. In addition, LLS provide valuable data for statistical analysis in lightning research. It isimportant to know the performance of such LLS. In the present study, the performance of the EarthNetworks Total Lightning Network (ENTLN) is studied using rocket-triggered lightning data acquired atthe International Center for Lightning 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 lightning.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.

  10. Thunderclouds and Lightning Conductors

    ERIC Educational Resources Information Center

    Martin, P. F.

    1973-01-01

    Discusses the historical background of the development of lightning conductors, describes the nature of thunderclouds and the lightning flash, and provides a calculation of the electric field under a thundercloud. Also discussed are point discharge currents and the attraction theory of the lightning conductor. (JR)

  11. Update Direct-Strike Lightning Environment for Stockpile-to-Target Sequence

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

    Uman, M A; Rakov, V A; Elisme, J O

    2008-10-01

    The University of Florida has surveyed all relevant publications reporting lightning characteristics and presents here an up-to-date version of the direct-strike lightning environment specifications for nuclear weapons published in 1989 by R. J. Fisher and M. A. Uman. Further, we present functional expressions for current vs. time, current derivative vs. time, second current derivative vs. time, charge transfer vs. time, and action integral (specific energy) vs. time for first return strokes, for subsequent return strokes, and for continuing currents; and we give sets of constants for these expressions so that they yield approximately the median and extreme negative lightning parametersmore » presented in this report. Expressions for the median negative lightning waveforms are plotted. Finally, we provide information on direct-strike lightning damage to metals such as stainless steel, which could be used as components of storage containers for nuclear waste materials; and we describe UF's new experimental research program to add to the sparse data base on the properties of positive lightning. Our literature survey, referred to above, is included in four Appendices. The following four sections (II, III, IV, and V) of this final report deal with related aspects of the research: Section II. Recommended Direct-Strike Median and Extreme Parameters; Section III. Time-Domain Waveforms for First Strokes, Subsequent Strokes, and Continuing Currents; Section IV. Damage to Metal Surfaces by Lightning Currents; and Section V. Measurement of the Characteristics of Positive Lightning. Results of the literature search used to derive the material in Section II and Section IV are found in the Appendices: Appendix 1. Return Stroke Current, Appendix 2. Continuing Current, Appendix 3. Positive Lightning, and Appendix 4. Lightning Damage to Metal Surfaces.« less

  12. Lightning safety of animals.

    PubMed

    Gomes, Chandima

    2012-11-01

    This paper addresses a concurrent multidisciplinary problem: animal safety against lightning hazards. In regions where lightning is prevalent, either seasonally or throughout the year, a considerable number of wild, captive and tame animals are injured due to lightning 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 lightning threats discussed.

  13. [Lightning strikes and lightning injuries in prehospital emergency medicine. Relevance, results, and practical implications].

    PubMed

    Hinkelbein, J; Spelten, O; Wetsch, W A

    2013-01-01

    Up to 32.2% of patients in a burn center suffer from electrical injuries. Of these patients, 2-4% present with lightning injuries. In Germany, approximately 50 people per year are injured by a lightning strike and 3-7 fatally. Typically, people involved in outdoor activities are endangered and affected. A lightning 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 lightning injuries, internal injuries are of special importance. Mortality ranges between 10 and 30% after a lightning strike. Emergency medical treatment is similar to common electrical injuries. Patients with lightning 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 lightning.

  14. University of Florida lightning research at the Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Uman, Martin A.; Thomson, Ewen M.

    1987-01-01

    A variety of basic and applied research programs are being conducted at the Kennedy Space Center. As an example of this research, the paper describes the University of Florida program to characterize the electric and magnetic fields of lightning and the coupling of those fields to utility power lines. Specifically, detailed consideration is given to the measurements of horizontal and vertical electric fields made during the previous three summers at KSC and the simultaneous measurements of the voltages on a 500 m test line made during the past two summers at KSC. Theory to support these measurements is also presented.

  15. Lightning Imaging Sensor (LIS) for the International Space Station (ISS): Mission Description and Science Goals

    NASA Technical Reports Server (NTRS)

    Blakeslee, R. J.; Christian, H. J.; Mach, D. M.; Buechler, D. E.; Koshak, W. J.; Walker, T. D.; Bateman, M.; Stewart, M. F.; O'Brien, S.; Wilson, T.; hide

    2015-01-01

    In recent years, the NASA Marshall Space Flight Center, the University of Alabama in Huntsville, and their partners have developed and demonstrated space-based lightning observations as an effective remote sensing tool for Earth science research and applications. The Lightning Imaging Sensor (LIS) on the Tropical Rainfall Measuring Mission (TRMM) continues to acquire global observations of total (i.e., intracloud and cloud-to-ground) lightning after 17 years on-orbit. However, TRMM is now low on fuel, so this mission will soon be completed. As a follow on to this mission, a space-qualified LIS built as the flight spare for TRMM has been selected for flight as a science mission on the International Space Station (ISS). The ISS LIS will be flown as a hosted payload on the Department of Defense Space Test Program (STP) H5 mission, which has a January 2016 baseline launch date aboard a SpaceX launch vehicle for a 2-4 year or longer mission. The LIS measures the amount, rate, and radiant energy of total lightning over the Earth. More specifically, it measures lightning during both day and night, with storm scale resolution (approx. 4 km), millisecond timing, and high, uniform detection efficiency, without any land-ocean bias. Lightning is a direct and most impressive response to intense atmospheric convection. It has been found that lightning measured by LIS can be quantitatively related to thunderstorm and other geophysical processes. Therefore, the ISS LIS lightning observations will continue to provide important gap-filling inputs to pressing Earth system science issues across a broad range of disciplines, including weather, climate, atmospheric chemistry, and lightning physics. A unique contribution from the ISS platform will be the availability of real-time lightning data, especially valuable for operational applications over data sparse regions such as the oceans. The ISS platform will also uniquely enable LIS to provide simultaneous and complementary observations

  16. Analysis of electrical transients created by lightning

    NASA Technical Reports Server (NTRS)

    Nanevicz, J. E.; Vance, E. F.

    1980-01-01

    A series of flight tests was conducted using a specially-instrumented NASA Learjet to study the electrical transients created on an aircraft by nearby lightning. The instrumentation included provisions for the time-domain and frequency-domain recording of the electrical signals induced in sensors located both on the exterior and on the interior of the aircraft. The design and calibration of the sensors and associated measuring systems is described together with the results of the flight test measurements. The results indicate that the concept of providing instrumentation to follow the lightning signal from propagation field, to aircraft skin current, to current on interior wiring is basically sound. The results of the measurement indicate that the high frequency signals associated with lightning stroke precursor activity are important in generating electromagnetic noise on the interior of the aircraft. Indeed, the signals produced by the precursors are often of higher amplitude and of longer duration that the pulse produced by the main return stroke.

  17. An Intrinsic Fiber-Optic Sensor for Structure Lightning Current Measurement

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.; Mata, Carlos T.; Mata, Angel. G.; Snyder, Gary P.

    2014-01-01

    An intrinsic optical-fiber sensor based on Faraday Effect is developed that is highly suitable for measuring lightning 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 lightning towers, the sensor can help validate other sensors and lightning 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 laboratory testing, including measuring current on an aluminum structure simulating an aircraft fuselage or a lightning tower. High current capabilities were demonstrated up to 200 kA at a lightning 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 lightning at the International Center for Lightning 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 lightning current measurement where low weight

  18. HAARP-based Investigations of Lightning-induced Nonlinearities within the D-Region Ionosphere

    NASA Astrophysics Data System (ADS)

    Moore, R. C.

    2015-12-01

    It is well-documented that energetic lightning can produce fantastical events with the lower ionosphere. Although the High-frequency Active Auroral Research Program (HAARP) transmitter is not as powerful as lightning, it can be used to investigate the nonlinear interactions that occur within the lower ionosphere, many of which also occur during lightning-induced ionospheric events. This paper presents the best experimental results obtained during D-region modification experiments performed by the University of Florida at the HAARP observatory between 2007 and 2014, including ELF/VLF wave generation experiments, wave-wave mixing experiments, and cross-modulation experiments. We emphasize the physical processes important for lightning-ionosphere interactions that can be directly investigated using HAARP.

  19. Cable coupling lightning transient qualification

    NASA Technical Reports Server (NTRS)

    Cook, M.

    1989-01-01

    Simulated lightning strike testing of instrumentation cabling on the redesigned solid rocket motor was performed. Testing consisted of subjecting the lightning evaluation test article to simulated lightning strikes and evaluating the effects of instrumentation cable transients on cables within the system tunnel. The maximum short-circuit current induced onto a United Space Boosters, Inc., operational flight cable within the systems tunnel was 92 A, and the maximum induced open-circuit voltage was 316 V. These levels were extrapolated to the worst-case (200 kA) condition of NASA specification NSTS 07636 and were also scaled to full-scale redesigned solid rocket motor dimensions. Testing showed that voltage coupling to cables within the systems tunnel can be reduced 40 to 90 dB and that current coupling to cables within the systems tunnel can be reduced 30 to 70 dB with the use of braided metallic sock shields around cables that are external to the systems tunnel. Testing also showed that current and voltage levels induced onto cables within the systems tunnel are partially dependant on the cables' relative locations within the systems tunnel. Results of current injections to the systems tunnel indicate that the dominant coupling mode on cables within the systems tunnel is not from instrumentation cables but from coupling through the systems tunnel cover seam apertures. It is recommended that methods of improving the electrical bonding between individual sections of the systems tunnel covers be evaluated. Further testing to better characterize redesigned solid rocket motor cable coupling effects as an aid in developing methods to reduce coupling levels, particularly with respect to cable placement within the systems tunnel, is also recommended.

  20. A Lightning Channel Retrieval Algorithm for the North Alabama Lightning Mapping Array (LMA)

    NASA Technical Reports Server (NTRS)

    Koshak, William; Arnold, James E. (Technical Monitor)

    2002-01-01

    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 Lightning Mapping Array (LMA), employs GPS timing and detects VHF radiation from discrete segments (effectively point emitters) that comprise the channel of lightning strokes within cloud and ground flashes. The network will support on-going ground validation activities of the low Earth orbiting Lightning 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 lightning in the Tennessee Valley, and will offer many interesting comparisons with other meteorological/geophysical wets associated with lightning 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) Lightning 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

  1. Lightning Phenomenology

    NASA Astrophysics Data System (ADS)

    Kawasaki, Zen

    This paper presents a phenomenological idea about lightning flash to share the back ground understanding for this special issue. Lightning 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.

  2. Number of lightning discharges causing damage to lightning arrester cables for aerial transmission lines in power systems

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

    Nikiforov, E. P.

    2009-07-15

    Damage by lightning discharges to lightning 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 lightning arrester cables occur when a tensile force acts on a cable heated to the melting point by a lightning current. The lightning currents required to heat a cable to this extent are greater for larger cable cross sections. The probability that a lightning discharge will develop decreases as the amplitude of the lightning current increases, which greatly reduces themore » number of lightning discharges which damage TK-70 cables compared to TK-50 cables. In order to increase the reliability of lightning arrester cables for 110 kV aerial transmission lines, TK-70 cables should be used in place of TK-50 cables. The number of lightning discharges per year which damage lightning 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

  3. Smart CMOS image sensor for lightning detection and imaging.

    PubMed

    Rolando, Sébastien; Goiffon, Vincent; Magnan, Pierre; Corbière, Franck; Molina, Romain; Tulet, Michel; Bréart-de-Boisanger, Michel; Saint-Pé, Olivier; Guiry, Saïprasad; Larnaudie, Franck; Leone, Bruno; Perez-Cuevas, Leticia; Zayer, Igor

    2013-03-01

    We present a CMOS image sensor dedicated to lightning detection and imaging. The detector has been designed to evaluate the potentiality of an on-chip lightning detection solution based on a smart sensor. This evaluation is performed in the frame of the predevelopment phase of the lightning detector that will be implemented in the Meteosat Third Generation Imager satellite for the European Space Agency. The lightning detection process is performed by a smart detector combining an in-pixel frame-to-frame difference comparison with an adjustable threshold and on-chip digital processing allowing an efficient localization of a faint lightning pulse on the entire large format array at a frequency of 1 kHz. A CMOS prototype sensor with a 256×256 pixel array and a 60 μm pixel pitch has been fabricated using a 0.35 μm 2P 5M technology and tested to validate the selected detection approach.

  4. 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.

  5. The Goes-R Geostationary Lightning Mapper (GLM)

    NASA Technical Reports Server (NTRS)

    Goodman, Steven J.; Blakeslee, Richard J.; Koshak, William J.; Mach, Douglas

    2011-01-01

    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 lightning detection (cloud and cloud-to-ground flashes) from the Geostationary Lightning Mapper (GLM), and improved storm diagnostic capability with the Advanced Baseline Imager. The GLM will map total lightning 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 Lightning Applications Team have begun to develop the Level 2 algorithms, cal/val performance monitoring tools, and new applications. Proxy total lightning data from the NASA Lightning 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.

  6. Measuring Method for Lightning Channel Temperature.

    PubMed

    Li, X; Zhang, J; Chen, L; Xue, Q; Zhu, R

    2016-09-26

    In this paper, we demonstrate the temperature of lightning channel utilizing the theory of lightning spectra and the model of local thermodynamic equilibrium (LTE). The impulse current generator platform (ICGS) was used to simulate the lightning discharge channel, and the spectral energy of infrared spectroscopy (930 nm) and the visible spectroscopy (648.2 nm) of the simulated lightning has been calculated. Results indicate that the peaks of luminous intensity of both infrared and visible spectra increase with the lightning current intensity in range of 5-50 kA. Based on the results, the temperature of the lightning channel is derived to be 6140.8-10424 K. Moreover, the temperature of the channel is approximately exponential to the lightning current intensity, which shows good agreement with that of the natural lightning cases.

  7. Measuring Method for Lightning Channel Temperature

    NASA Astrophysics Data System (ADS)

    Li, X.; Zhang, J.; Chen, L.; Xue, Q.; Zhu, R.

    2016-09-01

    In this paper, we demonstrate the temperature of lightning channel utilizing the theory of lightning spectra and the model of local thermodynamic equilibrium (LTE). The impulse current generator platform (ICGS) was used to simulate the lightning discharge channel, and the spectral energy of infrared spectroscopy (930 nm) and the visible spectroscopy (648.2 nm) of the simulated lightning has been calculated. Results indicate that the peaks of luminous intensity of both infrared and visible spectra increase with the lightning current intensity in range of 5-50 kA. Based on the results, the temperature of the lightning channel is derived to be 6140.8-10424 K. Moreover, the temperature of the channel is approximately exponential to the lightning current intensity, which shows good agreement with that of the natural lightning cases.

  8. Full-wave reflection of lightning long-wave radio pulses from the ionospheric D region: Comparison with midday observations of broadband lightning signals

    NASA Astrophysics Data System (ADS)

    Jacobson, Abram R.; Shao, Xuan-Min; Holzworth, Robert

    2010-05-01

    We are developing and testing a steep-incidence D region sounding method for inferring profile information, principally regarding electron density. The method uses lightning emissions (in the band 5-500 kHz) as the probe signal. The data are interpreted by comparison against a newly developed single-reflection model of the radio wave's encounter with the lower ionosphere. The ultimate application of the method will be to study transient, localized disturbances of the nocturnal D region, including those instigated by lightning itself. Prior to applying the method to study lightning-induced perturbations of the nighttime D region, we have performed a validation test against more stable and predictable daytime observations, where the profile of electron density is largely determined by direct solar X-ray illumination. This article reports on the validation test. Predictions from our recently developed full-wave ionospheric-reflection model are compared to statistical summaries of daytime lightning radiated waveforms, recorded by the Los Alamos Sferic Array. The comparison is used to retrieve best fit parameters for an exponential profile of electron density in the ionospheric D region. The optimum parameter values are compared to those found elsewhere using a narrowband beacon technique, which used totally different measurements, ranges, and modeling approaches from those of the work reported here.

  9. 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/2003APS..TSS3APS02K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003APS..TSS3APS02K"><span>Model of <span class="hlt">lightning</span> strike to a steel reinforce structure using PSpice</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Koone, Neil; Condren, Brian</p> <p>2003-03-01</p> <p>Surges and arcs from <span class="hlt">lightning</span> can pose hazards to personnel and sensitive equipment and processes. Steel reinforcement in structures can act as a Faraday cage mitigating <span class="hlt">lightning</span> effects. Knowing a structure's response to a <span class="hlt">lightning</span> strike allows hazards associated with <span class="hlt">lightning</span> to be analyzed. A model of <span class="hlt">lightning</span>'s response in a steel reinforced structure has been developed using PSpice (a commercial circuit simulation). Segments of rebar are modeled as inductors and resistors in series. A <span class="hlt">program</span> has been written to take architectural information of a steel reinforced structure and "build" a circuit network that is analogous to the network of reinforcement in a facility. A severe current waveform (simulating a 99th percentile <span class="hlt">lightning</span> strike), modeled as a current source, is introduced in the circuit network, and potential differences within the structure are determined using PSpice. A visual three-dimensional model of the facility displays the voltage distribution across the structure using color to indicate the potential difference relative to the floor. Clear air arcing distances can be calculated from the voltage distribution using a conservative value for the dielectric breakdown strength of air.</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://ntrs.nasa.gov/search.jsp?R=20100002096&hterms=four+seasons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dfour%2Bseasons','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20100002096&hterms=four+seasons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dfour%2Bseasons"><span>An Algorithm for Obtaining the Distribution of 1-Meter <span class="hlt">Lightning</span> Channel Segment Altitudes for Application in <span class="hlt">Lightning</span> NOx Production Estimation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Peterson, Harold; Koshak, William J.</p> <p>2009-01-01</p> <p>An algorithm has been developed to estimate the altitude distribution of one-meter <span class="hlt">lightning</span> channel segments. The algorithm is required as part of a broader objective that involves improving the <span class="hlt">lightning</span> NOx emission inventories of both regional air quality and global chemistry/climate models. The algorithm was <span class="hlt">tested</span> and applied to VHF signals detected by the North Alabama <span class="hlt">Lightning</span> Mapping Array (NALMA). The accuracy of the algorithm was characterized by comparing algorithm output to the plots of individual discharges whose lengths were computed by hand; VHF source amplitude thresholding and smoothing were applied to optimize results. Several thousands of <span class="hlt">lightning</span> flashes within 120 km of the NALMA network centroid were gathered from all four seasons, and were analyzed by the algorithm. The mean, standard deviation, and median statistics were obtained for all the flashes, the ground flashes, and the cloud flashes. One-meter channel segment altitude distributions were also obtained for the different seasons.</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/2060/20140013298','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 <span class="hlt">program</span> 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> <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://adsabs.harvard.edu/abs/2004AGUFMAE42A..07O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFMAE42A..07O"><span>The Anthropogenic/<span class="hlt">Lightning</span> Effects Around Houston: The Houston Environmental Aerosol Thunderstorm (HEAT) Project - 2005</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Orville, R. E.</p> <p>2004-12-01</p> <p>A major field <span class="hlt">program</span> will occur in summer 2005 to determine the sources and causes for the enhanced cloud-to-ground <span class="hlt">lightning</span> over Houston, Texas. This <span class="hlt">program</span> will be in association with simultaneous experiments supported by the Environmental Protection Agency (EPA) and the Texas Commission on Environmental Quality (TCEQ), formally the Texas Natural Resource Conservation Commission (TNRCC). Recent studies covering the period 1989-2002 document a 60 percent increase of cloud-to-ground <span class="hlt">lightning</span> in the Houston area as compared to surrounding background values, which is second in flash density only to the Tampa Bay, Florida area. We suggest that the elevated flash densities could result from several factors, including 1) the convergence due to the urban heat island effect and complex sea breeze (thermal hypothesis), and 2) the increasing levels of air pollution from anthropogenic sources producing numerous small cloud droplets and thereby suppressing mean droplet size (aerosol hypothesis). The latter effect would enable more cloud water to reach the mixed phase region where it is involved in the formation of precipitation and the separation of electric charge, leading to an enhancement of <span class="hlt">lightning</span>. The primary goals of HEAT are to examine the effects of (1) pollution, (2) the urban heat island, and (3) the complex coastline on storms and <span class="hlt">lightning</span> characteristics in the Houston area. The transport of air pollutants by Houston thunderstorms will be investigated. In particular, the relative amounts of <span class="hlt">lightning</span>-produced and convectively transported NOx into the upper troposphere will be determined, and a comparison of the different NOx sources in the urban area of Houston will be developed. The HEAT project is based on the observation that there is an enhancement in cloud-to-ground (CG) <span class="hlt">lightning</span>. Total <span class="hlt">lightning</span> (intracloud (IC) and CG) will be measured using a <span class="hlt">lightning</span> mapping system (LDAR II) to observe if there is an enhancement in intracloud <span class="hlt">lightning</span> as well.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890010408','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890010408"><span>Generalized three-dimensional experimental <span class="hlt">lightning</span> code (G3DXL) user's manual</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kunz, Karl S.</p> <p>1986-01-01</p> <p>Information concerning the <span class="hlt">programming</span>, maintenance and operation of the G3DXL computer <span class="hlt">program</span> is presented and the theoretical basis for the code is described. The <span class="hlt">program</span> computes time domain scattering fields and surface currents and charges induced by a driving function on and within a complex scattering object which may be perfectly conducting or a lossy dielectric. This is accomplished by modeling the object with cells within a three-dimensional, rectangular problem space, enforcing the appropriate boundary conditions and differencing Maxwell's equations in time. In the present version of the <span class="hlt">program</span>, the driving function can be either the field radiated by a <span class="hlt">lightning</span> strike or a direct <span class="hlt">lightning</span> strike. The F-106 B aircraft is used as an example scattering object.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120001505','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120001505"><span>An Overview of the Total <span class="hlt">Lightning</span> Jump Algorithm: Past, Present and Future 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.; Deierling, Wiebke; Kessinger, Cathy</p> <p>2011-01-01</p> <p>Rapid increases in total <span class="hlt">lightning</span> prior to the onset of severe and hazardous weather have been observed for several decades. These rapid increases are known as <span class="hlt">lightning</span> jumps and can precede the occurrence of severe weather by tens of minutes. Over the past decade, a significant effort has been made to quantify <span class="hlt">lightning</span> jump behavior in relation to its utility as a predictor of severe and hazardous weather. Based on a study of 34 thunderstorms that occurred in the Tennessee Valley, early work conducted in our group at Huntsville determined that it was indeed possible to create a reasonable operational <span class="hlt">lightning</span> jump algorithm (LJA) based on a statistical framework relying on the variance behavior of the <span class="hlt">lightning</span> trending signal. We the expanded this framework and <span class="hlt">tested</span> several variance-related LJA configurations on a much larger sample of 87 severe and non severe thunderstorms. This study determined that a configuration named the "2(sigma)" algorithm had the most promise in development of the operational LJA with a probability of detection (POD) of 87%, a false alarm rate (FAR) of 33%, a Heidke Skill Score (HSS) of 0.75. The 2(sigma) algorithm was then <span class="hlt">tested</span> on an even larger sample of 711 thunderstorms of all types from four regions of the country where total <span class="hlt">lightning</span> measurement capability existed. The result was very encouraging.Despite the larger number of storms and the inclusion of different regions of the country, the POD remained high (79%), the FAR was low (36%) and HSS was solid (0.71). Average lead time from jump to severe weather occurrence was 20.65 minutes, with a standard deviation of +/- 15 minutes. Also, trends in total <span class="hlt">lightning</span> were compared to cloud to ground (CG) <span class="hlt">lightning</span> trends, and it was determined that total <span class="hlt">lightning</span> trends had a higher POD (79% vs 66%), lower FAR (36% vs 54 %) and a better HSS (0.71 vs 0.55). From the 711-storm case study it was determined that a majority of missed events were due to severe weather producing</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('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/2060/20000039434','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000039434"><span>Analysis and Assessment of Peak <span class="hlt">Lightning</span> Current Probabilities at the NASA 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>Johnson, D. L.; Vaughan, W. W.</p> <p>1999-01-01</p> <p>This technical memorandum presents a summary by the Electromagnetics and Aerospace Environments Branch at the Marshall Space Flight Center of <span class="hlt">lightning</span> characteristics and <span class="hlt">lightning</span> criteria for the protection of aerospace vehicles. Probability estimates are included for certain <span class="hlt">lightning</span> strikes (peak currents of 200, 100, and 50 kA) applicable to the National Aeronautics and Space Administration Space Shuttle at the Kennedy Space Center, Florida, during rollout, on-pad, and boost/launch phases. Results of an extensive literature search to compile information on this subject are presented in order to answer key questions posed by the Space Shuttle <span class="hlt">Program</span> Office at the Johnson Space Center concerning peak <span class="hlt">lightning</span> current probabilities if a vehicle is hit by a <span class="hlt">lightning</span> cloud-to-ground stroke. Vehicle-triggered <span class="hlt">lightning</span> probability estimates for the aforementioned peak currents are still being worked. Section 4.5, however, does provide some insight on estimating these same peaks.</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://hdl.handle.net/2060/20140002740','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140002740"><span>Common Practice <span class="hlt">Lightning</span> Strike Protection Characterization Technique to Quantify Damage Mechanisms on Composite Substrates</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Szatkowski, George N.; Dudley, Kenneth L.; Koppen, Sandra V.; Ely, Jay J.; Nguyen, Truong X.; Ticatch, Larry A.; Mielnik, John J.; Mcneill, Patrick A.</p> <p>2013-01-01</p> <p>To support FAA certification airworthiness standards, composite substrates are subjected to <span class="hlt">lightning</span> direct-effect electrical waveforms to determine performance characteristics of the <span class="hlt">lightning</span> strike protection (LSP) conductive layers used to protect composite substrates. <span class="hlt">Test</span> results collected from independent LSP studies are often incomparable due to variability in <span class="hlt">test</span> procedures & applied practices at different organizations, which impairs performance correlations between different LSP data sets. Under a NASA supported contract, The Boeing Company developed technical procedures and documentation as guidance in order to facilitate a <span class="hlt">test</span> method for conducting universal common practice <span class="hlt">lightning</span> strike protection <span class="hlt">test</span> procedures. The procedures obtain conformity in future <span class="hlt">lightning</span> strike protection evaluations to allow meaningful performance correlations across data sets. This universal common practice guidance provides the manufacturing specifications to fabricate carbon fiber reinforced plastic (CFRP) <span class="hlt">test</span> panels, including finish, grounding configuration, and acceptable methods for pretest nondestructive inspection (NDI) and posttest destructive inspection. The <span class="hlt">test</span> operations guidance elaborates on the provisions contained in SAE ARP5416 to address inconsistencies in the generation of damage protection performance data, so as to provide for maximum achievable correlation across capable lab facilities. In addition, the guidance details a direct effects <span class="hlt">test</span> bed design to aid in quantification of the multi-physical phenomena surrounding a <span class="hlt">lightning</span> direct attachment supporting validation data requirements for the development of predictive computational modeling. The <span class="hlt">lightning</span> <span class="hlt">test</span> bed is designed to accommodate a repeatable installation procedure to secure the <span class="hlt">test</span> panel and eliminate <span class="hlt">test</span> installation uncertainty. It also facilitates a means to capture the electrical waveform parameters in 2 dimensions, along with the mechanical displacement and thermal</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRD..123..108B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRD..123..108B"><span>Determination of the Global-Average Charge Moment of a <span class="hlt">Lightning</span> Flash Using Schumann Resonances and the LIS/OTD <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>Boldi, Robert; Williams, Earle; Guha, Anirban</p> <p>2018-01-01</p> <p>In this paper, we use (1) the 20 year record of Schumann resonance (SR) signals measured at West Greenwich Rhode Island, USA, (2) the 19 year <span class="hlt">Lightning</span> Imaging Sensor (LIS)/Optical Transient Detector (OTD) <span class="hlt">lightning</span> data, and (3) the normal mode equations for a uniform cavity model to quantify the relationship between the observed Schumann resonance modal intensity and the global-average vertical charge moment change M (C km) per <span class="hlt">lightning</span> flash. This work, by integrating SR measurements with satellite-based optical measurements of global flash rate, accomplishes this quantification for the first time. To do this, we first fit the intensity spectra of the observed SR signals to an eight-mode, three parameter per mode, (symmetric) Lorentzian line shape model. Next, using the LIS/OTD <span class="hlt">lightning</span> data and the normal mode equations for a uniform cavity model, we computed the expected climatological-daily-average intensity spectra. We then regressed the observed modal intensity values against the expected modal intensity values to find the best fit value of the global-average vertical charge moment change of a <span class="hlt">lightning</span> flash (M) to be 41 C km per flash with a 99% confidence interval of ±3.9 C km per flash, independent of mode. Mode independence argues that the model adequately captured the modal intensity, the most important fit parameter herein considered. We also <span class="hlt">tested</span> this relationship for the presence of residual modal intensity at zero <span class="hlt">lightning</span> flashes per second and found no evidence that modal intensity is significantly different than zero at zero <span class="hlt">lightning</span> flashes per second, setting an upper limit to the amount of nonlightning contributions to the observed modal intensity.</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://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 <span class="hlt">test</span> 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/1982lse.....2....5J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1982lse.....2....5J"><span><span class="hlt">Lightning</span> protection of a modern wind energy system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jaeger, D.</p> <p></p> <p>Due to their considerable height and frequent location above flat terrain, wind energy systems may be struck by <span class="hlt">lightning</span>, with two types of severe effects: the physical destruction of structurally and/or mechanically important elements, such as a rotor blade, or the damage or interruption of system electrical and electronic equipment. The GROWIAN II DEMO <span class="hlt">lightning</span> protection <span class="hlt">program</span> has undertaken the development of measures which in their sophistication and complexity approximate those for aircraft. These protective measures are applied to the carbon fiber-reinforced plastic composite rotor blades, the rotor bearing, and electrical circuitry installed within the wind turbine's nacelle.</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/2017AGUFMAE33A2527B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE33A2527B"><span><span class="hlt">Lightning</span> Imaging Sensor (LIS) on the International Space Station (ISS): Launch, Installation, Activation, and First Results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blakeslee, R. J.; Christian, H. J., Jr.; Mach, D. M.; Buechler, D. E.; Wharton, N. A.; Stewart, M. F.; Ellett, W. T.; Koshak, W. J.; Walker, T. D.</p> <p>2017-12-01</p> <p>Over two decades, the NASA Marshall Space Flight Center, the University of Alabama in Huntsville, and their partners developed and demonstrated the effectiveness and value of space-based <span class="hlt">lightning</span> observations as a remote sensing tool for Earth science research and applications, and, in the process, established a robust global <span class="hlt">lightning</span> climatology. The <span class="hlt">Lightning</span> Imaging Sensor (LIS) on the Tropical Rainfall Measuring Mission (TRMM) provided global observations of tropical <span class="hlt">lightning</span> for an impressive 17 years before that mission came to a close in April 2015. Now a space-qualified LIS, built as the flight spare for TRMM, has been installed on the International Space Station (ISS) for a minimum two year mission following its SpaceX launch on February 19, 2017. The LIS, flown as a hosted payload on the Department of Defense Space <span class="hlt">Test</span> <span class="hlt">Program</span>-Houston 5 (STP-H5) mission, was robotically installed in an Earth-viewing position on the outside of the ISS, providing a great opportunity to not only extend the 17-year TRMM LIS record of tropical <span class="hlt">lightning</span> measurements but also to expand that coverage to higher latitudes missed by the TRMM mission. Since its activation, LIS has continuously observed the amount, rate, and radiant energy <span class="hlt">lightning</span> within its field-of-view as it orbits the Earth. A major focus of this mission is to better understand the processes which cause <span class="hlt">lightning</span>, as well as the connections between <span class="hlt">lightning</span> and subsequent severe weather events. This understanding is a key to improving weather predictions and saving lives and property here in the United States and around the world. The LIS measurements will also help cross-validate observations from the new Geostationary <span class="hlt">Lightning</span> Mapper (GLM) operating on NOAA's newest weather satellite GOES-16. An especially unique contribution from the ISS platform will be the availability of real-time <span class="hlt">lightning</span> data, especially valuable for operational forecasting and warning applications over data sparse regions such</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140011701','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140011701"><span>Variation of a <span class="hlt">Lightning</span> NOx Indicator for National Climate Assessment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koshak, William; Vant-Hull, B.; McCaul, E. W.; Peterson, H. S.</p> <p>2014-01-01</p> <p><span class="hlt">Lightning</span> nitrogen oxides (LNOx) indirectly influences our climate since these molecules are important in controlling the concentration of ozone (O3) and hydroxyl radicals (OH) in the atmosphere [Huntrieser et al., 1998]. In support of the National Climate Assessment (NCA) <span class="hlt">program</span>, satellite <span class="hlt">Lightning</span> Imaging Sensor (LIS; Christian et al. [1999]; Cecil et al. [2014]) data is used to estimate LNOx production over the southern portion of the conterminous US for the 16 year period 1998-2013.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhDT.......134G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhDT.......134G"><span>Properties of <span class="hlt">Lightning</span> Strike Protection Coatings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gagne, Martin</p> <p></p> <p>Composite materials are being increasingly used by many industries. In the case of aerospace companies, those materials are installed on their aircraft to save weight, and thus, fuel costs. These aircraft are lighter, but the loss of electrical conductivity makes aircraft vulnerable to <span class="hlt">lightning</span> strikes, which hit commercial aircrafts on average once per year. This makes <span class="hlt">lightning</span> strike protection very important, and while current metallic expanded copper foils offer good protection, they increase the weight of composites. Therefore, under the CRIAQ COMP-502 project, a team of industrial partners and academic researchers are investigating new conductive coatings with the following characteristics: High electromagnetic protection, high mechanical resistance, good environmental protection, manufacturability and moderate cost. The main objectives of this thesis, as part of this project, was to determine the main characteristics, such as electrical and tribomechanical properties, of conductive coatings on composite panels. Their properties were also to be <span class="hlt">tested</span> after destructive <span class="hlt">tests</span> such as current injection and environmental <span class="hlt">testing</span>. Bombardier Aerospace provided the substrate, a composite of carbon fiber reinforced epoxy matrix, and the current commercial product, a surfacing film that includes an expanded copper foil used to compare with the other coatings. The conductive coatings fabricated by the students are: silver nanoparticles inside a binding matrix (PEDOT:PSS or a mix of Epoxy and PEDOT:PSS), silvered carbon nanofibers embedded in the surfacing film, cold sprayed tin, graphene oxide functionalized with silver nanowires, and electroless plated silver. Additionally as part of the project and thesis, magnetron sputtered aluminum coated samples were fabricated. There are three main types of <span class="hlt">tests</span> to characterize the conductive coatings: electrical, mechanical and environmental. Electrical <span class="hlt">tests</span> consist of finding the sheet resistance and specific resistivity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120001475','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120001475"><span><span class="hlt">Lightning</span> Initiation Forecasting: An Operational Dual-Polarimetric Radar Technique</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Woodard, Crystal J.; Carey, L. D.; Petersen, W. A.; Roeder, W. P.</p> <p>2011-01-01</p> <p>The objective of this NASA MSFC and NOAA CSTAR funded study is to develop and <span class="hlt">test</span> operational forecast algorithms for the prediction of <span class="hlt">lightning</span> initiation utilizing the C-band dual-polarimetric radar, UAHuntsville's Advanced Radar for Meteorological and Operational Research (ARMOR). Although there is a rich research history of radar signatures associated with <span class="hlt">lightning</span> initiation, few studies have utilized dual-polarimetric radar signatures (e.g., Z(sub dr) columns) and capabilities (e.g., fuzzy-logic particle identification [PID] of precipitation ice) in an operational algorithm for first flash forecasting. The specific goal of this study is to develop and <span class="hlt">test</span> polarimetric techniques that enhance the performance of current operational radar reflectivity based first flash algorithms. Improving <span class="hlt">lightning</span> watch and warning performance will positively impact personnel safety in both work and leisure environments. Advanced warnings can provide space shuttle launch managers time to respond appropriately to secure equipment and personnel, while they can also provide appropriate warnings for spectators and players of leisure sporting events to seek safe shelter. Through the analysis of eight case dates, consisting of 35 pulse-type thunderstorms and 20 non-thunderstorm case studies, <span class="hlt">lightning</span> initiation forecast techniques were developed and <span class="hlt">tested</span>. The hypothesis is that the additional dual-polarimetric information could potentially reduce false alarms while maintaining high probability of detection and increasing lead-time for the prediction of the first <span class="hlt">lightning</span> flash relative to reflectivity-only based techniques. To <span class="hlt">test</span> the hypothesis, various physically-based techniques using polarimetric variables and/or PID categories, which are strongly correlated to initial storm electrification (e.g., large precipitation ice production via drop freezing), were benchmarked against the operational reflectivity-only based approaches to find the best compromise between</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('https://ntrs.nasa.gov/search.jsp?R=20080013626&hterms=Wrf&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DWrf','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080013626&hterms=Wrf&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DWrf"><span>Use of High-Resolution WRF Simulations to Forecast <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>McCaul, E. W., Jr.; LaCasse, K.; Goodman, S. J.; Cecil, D. J.</p> <p>2008-01-01</p> <p>Recent observational studies have confirmed the existence of a robust statistical relationship between <span class="hlt">lightning</span> flash rates and the amount of large precipitating ice hydrometeors aloft in storms. This relationship is exploited, in conjunction with the capabilities of cloud-resolving forecast models such as WRF, to forecast explicitly the threat of <span class="hlt">lightning</span> from convective storms using selected output fields from the model forecasts. The simulated vertical flux of graupel at -15C and the shape of the simulated reflectivity profile are <span class="hlt">tested</span> in this study as proxies for charge separation processes and their associated <span class="hlt">lightning</span> risk. Our <span class="hlt">lightning</span> forecast method differs from others in that it is entirely based on high-resolution simulation output, without reliance on any climatological data. short [6-8 h) simulations are conducted for a number of case studies for which three-dmmensional <span class="hlt">lightning</span> validation data from the North Alabama <span class="hlt">Lightning</span> Mapping Array are available. Experiments indicate that initialization of the WRF model on a 2 km grid using Eta boundary conditions, Doppler radar radial velocity fields, and METAR and ACARS data y&eld satisfactory simulations. __nalyses of the <span class="hlt">lightning</span> threat fields suggests that both the graupel flux and reflectivity profile approaches, when properly calibrated, can yield reasonable <span class="hlt">lightning</span> threat forecasts, although an ensemble approach is probably desirable in order to reduce the tendency for misplacement of modeled storms to hurt the accuracy of the forecasts. Our <span class="hlt">lightning</span> threat forecasts are also compared to other more traditional means of forecasting thunderstorms, such as those based on inspection of the convective available potential energy field.</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('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> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023331','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023331"><span>A survey of laser <span class="hlt">lightning</span> rod techniques</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Barnes, Arnold A., Jr.; Berthel, Robert O.</p> <p>1991-01-01</p> <p>The work done to create a laser <span class="hlt">lightning</span> rod (LLR) is discussed. Some ongoing research which has the potential for achieving an operational laser <span class="hlt">lightning</span> rod for use in the protection of missile launch sites, launch vehicles, and other property is discussed. Because of the ease with which a laser beam can be steered into any cloud overhead, an LLR could be used to ascertain if there exists enough charge in the clouds to discharge to the ground as triggered <span class="hlt">lightning</span>. This leads to the possibility of using LLRs to <span class="hlt">test</span> clouds prior to launching missiles through the clouds or prior to flying aircraft through the clouds. LLRs could also be used to probe and discharge clouds before or during any hazardous ground operations. Thus, an operational LLR may be able to both detect such sub-critical electrical fields and effectively neutralize them.</p> </li> <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://ntrs.nasa.gov/search.jsp?R=20090009350&hterms=chemistry+chemicals&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dchemistry%2Bchemicals','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20090009350&hterms=chemistry+chemicals&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dchemistry%2Bchemicals"><span>Production of NOx by <span class="hlt">Lightning</span> and its Effects on Atmospheric Chemistry</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pickering, Kenneth E.</p> <p>2009-01-01</p> <p>Production of NO(x) by <span class="hlt">lightning</span> remains the NO(x) source with the greatest uncertainty. Current estimates of the global source strength range over a factor of four (from 2 to 8 TgN/year). Ongoing efforts to reduce this uncertainty through field <span class="hlt">programs</span>, cloud-resolved modeling, global modeling, and satellite data analysis will be described in this seminar. Representation of the <span class="hlt">lightning</span> source in global or regional chemical transport models requires three types of information: the distribution of <span class="hlt">lightning</span> flashes as a function of time and space, the production of NO(x) per flash, and the effective vertical distribution of the <span class="hlt">lightning</span>-injected NO(x). Methods of specifying these items in a model will be discussed. For example, the current method of specifying flash rates in NASA's Global Modeling Initiative (GMI) chemical transport model will be discussed, as well as work underway in developing algorithms for use in the regional models CMAQ and WRF-Chem. A number of methods have been employed to estimate either production per <span class="hlt">lightning</span> flash or the production per unit flash length. Such estimates derived from cloud-resolved chemistry simulations and from satellite NO2 retrievals will be presented as well as the methodologies employed. Cloud-resolved model output has also been used in developing vertical profiles of <span class="hlt">lightning</span> NO(x) for use in global models. Effects of <span class="hlt">lightning</span> NO(x) on O3 and HO(x) distributions will be illustrated regionally and globally.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120003035','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120003035"><span>A Probabilistic, Facility-Centric Approach to <span class="hlt">Lightning</span> Strike Location</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.; Roeder, William p.; Merceret, Francis J.</p> <p>2012-01-01</p> <p>A new probabilistic facility-centric approach to <span class="hlt">lightning</span> strike location has been developed. This process uses the bivariate Gaussian distribution of probability density provided by the current <span class="hlt">lightning</span> location error ellipse for the most likely location of a <span class="hlt">lightning</span> stroke and integrates it to determine the probability that the stroke is inside any specified radius of any location, even if that location is not centered on or even with the location error ellipse. This technique is adapted from a method of calculating the probability of debris collisionith spacecraft. Such a technique is important in spaceport processing activities because it allows engineers to quantify the risk of induced current damage to critical electronics due to nearby <span class="hlt">lightning</span> strokes. This technique was <span class="hlt">tested</span> extensively and is now in use by space launch organizations at Kennedy Space Center and Cape Canaveral Air Force Station. Future applications could include forensic meteorology.</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('https://ntrs.nasa.gov/search.jsp?R=20000074489&hterms=rodgers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26Nf%3DPublication-Date%257CBTWN%2B19940101%2B20001231%26N%3D0%26No%3D20%26Ntt%3Drodgers','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000074489&hterms=rodgers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26Nf%3DPublication-Date%257CBTWN%2B19940101%2B20001231%26N%3D0%26No%3D20%26Ntt%3Drodgers"><span>Tropical Cyclone <span class="hlt">Lightning</span> Distribution and Its Relationship to Convection and Intensity Change</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rodgers, Edward; Wienman, James; Pierce, Harold; Olson, William</p> <p>2000-01-01</p> <p>The long distance National <span class="hlt">Lightning</span> Detection Network (NLDN) was used to monitor the distribution of <span class="hlt">lightning</span> strokes in various 1998 and 1999 western North Atlantic tropical cyclones. These ground-based <span class="hlt">lightning</span> observations together with the Defense Meteorological Satellite <span class="hlt">Program</span> (DMSP) Special Sensor Microwave/Imager (SSM/I) and the Tropical Rain Mapping Mission (TRMM) Microwave Instrument (TMI) derived convective rain rates were used to monitor the propagation of electrically charged convective rain bands aid to qualitatively estimate intensification. An example of the <span class="hlt">lightning</span> analyses was performed on hurricane George between 25-28 September, 1998 when the system left Key West and moved towards the Louisiana coast. During this period of time, George's maximum winds increased from 38 to 45 meters per second on 25 September and then remained steady state until it made landfall. Time-radius displays of the <span class="hlt">lightning</span> strokes indicated that the greatest number of <span class="hlt">lightning</span> strokes occurred within the outer core region (greater than 165 km) with little or no <span class="hlt">lightning</span> strokes at radii less than 165 km. The trend in these <span class="hlt">lightning</span> strokes decreased as George move into the Gulf of Mexico and showed no inward propagation. The lack inward propagating <span class="hlt">lightning</span> strokes with time indicated that there was no evidence that an eye wall replacement was occurring that could alter George's intensity. Since George was steady state at this time, this result is not surprising. Time-azimuth displays of <span class="hlt">lightning</span> strokes in an annulus whose outer and inner radii were respectively, 222 and 333 km from George's center were also constructed. A result from this analysis indicated that the maximum number of strokes occurred in the forward and rear right quadrant when George was over the Gulf of Mexico. This result is, consistent with the aircraft and satellite observations of maximum rainfall.</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://hdl.handle.net/2060/19820015803','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19820015803"><span>Evaluation of <span class="hlt">lightning</span> accommodation systems for wind-driven turbine rotors</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bankaitis, H.</p> <p>1982-01-01</p> <p>Wind-driven turbine generators are being evaluated as an alternative source of electric energy. Areas of favorable location for the wind-driven turbines (high wind density) coincide with areas of high incidence of thunderstorm activity. These locations, coupled with the 30-m or larger diameter rotor blades, make the wind-driven turbine blades probable terminations for <span class="hlt">lightning</span> strikes. Several candidate systems of <span class="hlt">lightning</span> accommodation for composite-structural-material blades were designed and their effectiveness evaluated by submitting the systems to simulated <span class="hlt">lightning</span> strikes. The <span class="hlt">test</span> data were analyzed and system design were reviewed on the basis of the analysis.</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://adsabs.harvard.edu/abs/2016JMetR..30..800Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JMetR..30..800Z"><span>A review of advances in <span class="hlt">lightning</span> observations during the past decade in Guangdong, China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Yijun; Lü, Weitao; Chen, Shaodong; Zheng, Dong; Zhang, Yang; Yan, Xu; Chen, Lüwen; Dong, Wansheng; Dan, Jianru; Pan, Hanbo</p> <p>2016-08-01</p> <p>This paper reviews recent advances in understanding the physical processes of artificially triggered <span class="hlt">lightning</span> and natural <span class="hlt">lightning</span> as well as the progress in <span class="hlt">testing</span> <span class="hlt">lightning</span> protection technologies, based on a series of <span class="hlt">lightning</span> field campaigns jointly conducted by the Chinese Academy of Meteorological Sciences and Guangdong Meteorological Bureau since 2006. During the decade-long series of <span class="hlt">lightning</span> field experiments, the technology of rocket-wire artificially triggered <span class="hlt">lightning</span> has been improved, and has successfully triggered 94 <span class="hlt">lightning</span> flashes. Through direct <span class="hlt">lightning</span> current waveform measurements, an average return stroke peak current of 16 kA was obtained. The phenomenon that the downward leader connects to the lateral surface of the upward leader in the attachment process was discovered, and the speed of the upward leader during the connection process being significantly greater than that of the downward leader was revealed. The characteristics of several return strokes in cloud-to-ground lighting have also been unveiled, and the mechanism causing damage to <span class="hlt">lightning</span> protection devices (i.e., ground potential rise within the rated current) was established. The performance of three <span class="hlt">lightning</span> monitoring systems in Guangdong Province has also been quantitatively assessed.</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=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('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. <span class="hlt">Tests</span> 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> </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://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('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('http://hdl.handle.net/2060/19800023871','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800023871"><span>Improved <span class="hlt">test</span> methods for determining <span class="hlt">lightning</span>-induced voltages in aircraft</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Crouch, K. E.; Plumer, J. A.</p> <p>1980-01-01</p> <p>A lumped parameter transmission line with a surge impedance matching that of the aircraft and its return lines was evaluated as a replacement for earlier current generators. Various <span class="hlt">test</span> circuit parameters were evaluated using a 1/10 scale relative geometric model. Induced voltage response was evaluated by taking measurements on the NASA-Dryden Digital Fly by Wire F-8 aircraft. Return conductor arrangements as well as other circuit changes were also evaluated, with all induced voltage measurements being made on the same circuit for comparison purposes. The lumped parameter transmission line generates a concave front current wave with the peak di/dt near the peak of the current wave which is more representative of <span class="hlt">lightning</span>. However, the induced voltage measurements when scaled by appropriate scale factors (peak current or di/dt) resulting from both techniques yield comparable results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750005958','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750005958"><span>Tantalum capacitor behavior under fast transient overvoltages. [circuit protection 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>Zill, J. A.; Castle, K. D.</p> <p>1974-01-01</p> <p>Tantalum capacitors were <span class="hlt">tested</span> to determine failure time when subjected to short-duration, high-voltage surges caused by <span class="hlt">lightning</span> strikes. <span class="hlt">Lightning</span> is of concern to NASA because of possible damage to critical spacecraft circuits. The <span class="hlt">test</span> was designed to determine the minimum time for tantalum capacitor failure and the amount of overvoltage a capacitor could survive, without permanent damage, in 100 microseconds. All <span class="hlt">tested</span> exhibited good recovery from the transient one-shot pulses with no failure at any voltage, forward or reverse, in less than 25 microseconds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoRL..42.6051D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoRL..42.6051D"><span>First images of thunder: Acoustic imaging 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>Dayeh, M. A.; Evans, N. D.; Fuselier, S. A.; Trevino, J.; Ramaekers, J.; Dwyer, J. R.; Lucia, R.; Rassoul, H. K.; Kotovsky, D. A.; Jordan, D. M.; Uman, M. A.</p> <p>2015-07-01</p> <p>An acoustic camera comprising a linear microphone array is used to image the thunder signature of triggered <span class="hlt">lightning</span>. Measurements were taken at the International Center for <span class="hlt">Lightning</span> Research and <span class="hlt">Testing</span> in Camp Blanding, FL, during the summer of 2014. The array was positioned in an end-fire orientation thus enabling the peak acoustic reception pattern to be steered vertically with a frequency-dependent spatial resolution. On 14 July 2014, a <span class="hlt">lightning</span> event with nine return strokes was successfully triggered. We present the first acoustic images of individual return strokes at high frequencies (>1 kHz) and compare the acoustically inferred profile with optical images. We find (i) a strong correlation between the return stroke peak current and the radiated acoustic pressure and (ii) an acoustic signature from an M component current pulse with an unusual fast rise time. These results show that acoustic imaging enables clear identification and quantification of thunder sources as a function of <span class="hlt">lightning</span> channel altitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990095061','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990095061"><span><span class="hlt">Lightning</span> Mapper Sensor Lens Assembly S.O. 5459: Project Management Plan</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zeidler, Janet</p> <p>1999-01-01</p> <p>Kaiser Electro-Optics, Inc. (KEO) has developed this Project Management Plan for the <span class="hlt">Lightning</span> Mapper Sensor (LMS) <span class="hlt">program</span>. KEO has integrated a team of experts in a structured <span class="hlt">program</span> management organization to meet the needs of the LMS <span class="hlt">program</span>. The project plan discusses KEO's approach to critical <span class="hlt">program</span> elements including <span class="hlt">Program</span> Management, Quality Assurance, Configuration Management, and Schedule.</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://www.ncbi.nlm.nih.gov/pubmed/15777170','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15777170"><span>Modern concepts of treatment and prevention of <span class="hlt">lightning</span> injuries.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Edlich, Richard F; Farinholt, Heidi-Marie A; Winters, Kathryne L; Britt, L D; Long, William B</p> <p>2005-01-01</p> <p><span class="hlt">Lightning</span> is the second most common cause of weather-related death in the United States. <span class="hlt">Lightning</span> is a natural atmospheric discharge that occurs between regions of net positive and net negative electric charges. There are several types of <span class="hlt">lightning</span>, including streak <span class="hlt">lightning</span>, sheet <span class="hlt">lightning</span>, ribbon <span class="hlt">lightning</span>, bead <span class="hlt">lightning</span>, and ball <span class="hlt">lightning</span>. <span class="hlt">Lightning</span> causes injury through five basic mechanisms: direct strike, flash discharge (splash), contact, ground current (step voltage), and blunt trauma. While persons struck by <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span> victims. Immediate resuscitation of people struck by <span class="hlt">lightning</span> greatly affects the prognosis. Electrocardiographic changes observed following <span class="hlt">lightning</span> accidents are probably from primary electric injury or burns of the myocardium without coronary artery occlusion. <span class="hlt">Lightning</span> 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 <span class="hlt">lightning</span> include amnesia and confusion, immediate loss of consciousness, weakness, intracranial injuries, and even brief aphasia. Other organ systems injured by <span class="hlt">lightning</span> include the eye, ear, gastrointestinal system, skin, and musculoskeletal system. The best treatment of <span class="hlt">lightning</span> injuries is prevention. The <span class="hlt">Lightning</span> Safety Guidelines devised by the <span class="hlt">Lightning</span> Safety Group should be instituted in the United States and other nations to prevent these devastating injuries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110008697','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110008697"><span>The GOES-R Series 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 M.</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), which will have just completed Critical Design Review and move forward into the construction phase of instrument development. The GLM will operate 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 (an engineering development unit 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, 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 (LIS) on the Tropical Rainfall Measuring Mission (TRMM) satellite and regional ground-based <span class="hlt">lightning</span> networks are being used to develop the pre-launch algorithms, <span class="hlt">test</span> data sets, and applications, as well as improve our knowledge of thunderstorm initiation and evolution. In this presentation we review the planned implementation of the instrument and suite of operational algorithms</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=19990084078&hterms=metal+detector&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dmetal%2Bdetector','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990084078&hterms=metal+detector&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dmetal%2Bdetector"><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.; Solakiewica, R. J.</p> <p>1998-01-01</p> <p>Electric field measurements are fundamental to the study of thunderstorm electrification, thundercloud charge structure, and the determination of the locations and magnitudes of charges deposited by <span class="hlt">lightning</span>. Continuous field observations can also be used to warn of impending electrical hazards. For example, the USAF Eastern Range (ER) and NASA Kennedy Space Center (KSC) in Florida currently operate a ground-based network of electric field mill sensors to warn against <span class="hlt">lightning</span> hazards to space vehicle operations/launches. The sensors provide continuous recordings of the ambient field. Others investigators have employed flat-plate electric field antennas to detect changes In the ambient field due to <span class="hlt">lightning</span>. In each approach, electronic circuitry is used to directly detect and amplify the effects of the ambient field on an exposed metal conductor (antenna plate); in the case of continuous field recordings, the antenna plate is alternately shielded and unshielded by a grounded conductor. In this work effort, an alternate optical method for detecting <span class="hlt">lightning</span>-caused electric field changes is Introduced. The primary component in the detector is an anisotropic electro-optic crystal of potassium di-hydrogen phosphate (chemically written as KH2PO4 (KDP)). When a voltage Is placed across the electro-optic crystal, the refractive Indices of the crystal change. This change alters the polarization state of a laser light beam that is passed down the crystal optic axis. With suitable application of vertical and horizontal polarizers, a light transmission measurement is related to the applied crystal voltage (which in turn Is related to the <span class="hlt">lightning</span> caused electric field change). During the past two years, all critical optical components were procured, assembled, and aligned. An optical housing, calibration set-up, and data acquisition system was integrated for breadboard <span class="hlt">testing</span>. The sensor was deployed at NASA Marshall Space Flight Center (MSFC) in the summer of 1998 to</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=19800013446&hterms=emp&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Demp','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19800013446&hterms=emp&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Demp"><span>Electromagnetic sensors for general <span class="hlt">lightning</span> application</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.; Onell, J. P.; Moore, C. B.; Sower, G. D.</p> <p>1980-01-01</p> <p>Electromagnetic sensors for general <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span> measurements, but there are some special cases of <span class="hlt">lightning</span> measurements involving direct strikes which require special design considerations for the sensors. The sensors and instrumentation used by NMIMT in collecting data on <span class="hlt">lightning</span> at South Baldy peak in central New Mexico during the 1978 and 1979 <span class="hlt">lightning</span> seasons are also discussed. The Langmuir Laboratory facilities and details of the underground shielded instrumentation room and recording equipment are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMAE22A..03W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMAE22A..03W"><span>Why does negative CG <span class="hlt">lightning</span> have subsequent return strokes?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilkes, R. A.; Kotovsky, D. A.; Uman, M. A.; Carvalho, F. L.; Jordan, D.</p> <p>2017-12-01</p> <p>It is not understood why cloud-to-ground (CG) <span class="hlt">lightning</span> flashes lowering negative charge often produce discrete dart-leader/return-stroke sequences rather than having the first stroke drain the available cloud charge, as is almost always the case for CG <span class="hlt">lightning</span> lowering positive charge. Triggered <span class="hlt">lightning</span> data obtained at the International Center for <span class="hlt">Lightning</span> Research and <span class="hlt">Testing</span> (ICLRT) in north-central Florida have been analyzed to clarify the subsequent return-stroke process. In summers 2013 through 2016 at the ICLRT, 53% of the rocket launches did not initiate any part of a <span class="hlt">lightning</span> flash, 13% of the rocket launches created an initial stage only (ISO) and failed to produce a following dart-leader/return-stroke sequences, and 34% of rocket launches produced an initial stage (IS) followed by return strokes. The IS of the triggered <span class="hlt">lightning</span> consists of the upward positive leader and a following initial continuing current, both being responsible for transporting negative charge from the cloud to ground. Our ISO events may well have some commonality with the roughly 20 percent of natural CG flashes that fail to produce a dart-leader/return-stroke. We have analyzed the IS of 41 triggered <span class="hlt">lightning</span> flashes with (19 cases) and without (22 cases) following return strokes and compared areas and heights of the flash using data collected by a <span class="hlt">Lightning</span> Mapping Array (LMA). In our preliminary analysis, we can find no geometrical feature of the <span class="hlt">lightning</span> channel during the IS that will predict the occurrence or lack of occurrence of following return strokes. We also have compared the triggered-<span class="hlt">lightning</span> electrical current and charge transfer observed at the ground. We found that the average current, duration, and charge transfer during the IS for ISO events is each about half that of ISs analyzed which are followed by dart-leader/return-stroke sequences, contrary to the results presented from the GCOELD in China. Summarizing, there appear to be no differences in the</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/2018AtmRe.205...26J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AtmRe.205...26J"><span>Remote sensing of the <span class="hlt">lightning</span> heating effect duration with ground-based microwave radiometer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiang, Sulin; Pan, Yun; Lei, Lianfa; Ma, Lina; Li, Qing; Wang, Zhenhui</p> <p>2018-06-01</p> <p>Artificially triggered <span class="hlt">lightning</span> events from May 26, 2017 to July 16, 2017 in Guangzhou Field Experiment Site for <span class="hlt">Lightning</span> Research and <span class="hlt">Test</span> (GFESL) were intentionally remotely sensed with a ground-based microwave radiometer for the first time in order to obtain the features of <span class="hlt">lightning</span> heating effect. The microwave radiometer antenna was adjusted to point at a certain elevation angle towards the expected artificially triggered <span class="hlt">lightning</span> discharging path. Eight of the 16 successfully artificially triggered <span class="hlt">lightning</span> events were captured and the brightness temperature data at four frequencies in K and V bands were obtained. The results from data time series analysis show that artificially triggered <span class="hlt">lightning</span> can make the radiometer generate brightness temperature pulses, and the amplitudes of these pulses are in the range of 2.0 K to 73.8 K. The brightness temperature pulses associated with 7 events can be used to estimate the duration of <span class="hlt">lightning</span> heating effect through accounting the number of the pulses in the continuous pulse sequence and the sampling interval between four frequencies. The maximum duration of the <span class="hlt">lightning</span> heating effect is 1.13 s, the minimum is 0.172 s, and the average is 0.63 s.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100021010','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100021010"><span>Assessing Operational Total <span class="hlt">Lightning</span> Visualization Products</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.; Darden, Christopher B.; Nadler, David J.</p> <p>2010-01-01</p> <p>In May 2003, NASA's Short-term Prediction Research and Transition (SPoRT) <span class="hlt">program</span> successfully provided total <span class="hlt">lightning</span> data from the North Alabama <span class="hlt">Lightning</span> Mapping Array (NALMA) to the National Weather Service (NWS) office in Huntsville, Alabama. The major accomplishment was providing the observations in real-time to the NWS in the native Advanced Weather Interactive Processing System (AWIPS) decision support system. Within days, the NALMA data were used to issue a tornado warning initiating seven years of ongoing support to the NWS' severe weather and situational awareness operations. With this success, SPoRT now provides real-time NALMA data to five forecast offices as well as working to transition data from total <span class="hlt">lightning</span> networks at Kennedy Space Center and the White Sands Missile Range to the surrounding NWS offices. The only NALMA product that has been transitioned to SPoRT's partner NWS offices is the source density product, available at a 2 km resolution in 2 min intervals. However, discussions with users of total <span class="hlt">lightning</span> data from other networks have shown that other products are available, ranging from spatial and temporal variations of the source density product to the creation of a flash extent density. SPoRT and the Huntsville, Alabama NWS are evaluating the utility of these variations as this has not been addressed since the initial transition in 2003. This preliminary analysis will focus on what products will best support the operational warning decision process. Data from 19 April 2009 are analyzed. On this day, severe thunderstorms formed ahead of an approaching cold front. Widespread severe weather was observed, primarily south of the Tennessee River with multiple, weak tornadoes, numerous severe hail reports, and wind. This preliminary analysis is the first step in evaluation which product(s) are best suited for operations. The ultimate goal is selecting a single product for use with all total <span class="hlt">lightning</span> networks to streamline training and</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://adsabs.harvard.edu/abs/2010AGUFMAE21B0275M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMAE21B0275M"><span>Modeling Long-Distance ELF Radio Atmospherics Generated 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>Moore, R. C.; Kunduri, B.; Anand, S.; Dupree, N.; Mitchell, M.; Agrawal, D.</p> <p>2010-12-01</p> <p>This paper addresses the generation and propagation of radio atmospherics (sferics) radiated by <span class="hlt">lightning</span> in order to assess the ability to infer the electrical properties of <span class="hlt">lightning</span> from great distances. This ability may prove to greatly enhance the understanding of <span class="hlt">lightning</span> processes that are associated with the production of transient luminous events (TLEs) as well as other ionospheric effects associated with <span class="hlt">lightning</span>. The modeling of the sferic waveform is carried out using a modified version of the Long Wavelength Propagation Capability (LWPC) code developed by the Naval Ocean Systems Center over a period of many years. 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. Unlike other similar efforts, the modified code presented preserves the ability of LWPC to account for waveguide mode-coupling and to account for changes to the electrical properties of the ground and ionosphere along the propagation path. The effort described is conducted in advance of the deployment of a global extremely low frequency (ELF) magnetic field array, which is presently under construction. The global ELF array is centered on the International Center for <span class="hlt">Lightning</span> Research and <span class="hlt">Testing</span> (ICLRT) located at Camp Blanding, Florida. The ICLRT is well-known for conducting rocket-triggered <span class="hlt">lightning</span> experiments over the last 15-20 years. This paper uses <span class="hlt">lightning</span> current waveforms directly measured at the base of the <span class="hlt">lightning</span> channel (observations performed at the ICLRT) as an input to the model to predict the sferic waveform to be observed by the array under various ionospheric conditions. An analysis of the predicted sferic waveforms is presented, and the components of the <span class="hlt">lightning</span> current waveform that most effectively excite the Earth-ionosphere waveguide are identified.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140011691','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140011691"><span>Physical and Dynamical Linkages Between <span class="hlt">Lightning</span> Jumps and Storm Conceptual Models</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.; Carey, Lawrence D.; Schultz, Elise V.; Blakeslee, Richard J.; Goodman, Steven J.</p> <p>2014-01-01</p> <p>The presence and rates of total <span class="hlt">lightning</span> are both correlated to and physically dependent upon storm updraft strength, mixed phase precipitation volume and the size of the charging zone. The updraft modulates the ingredients necessary for electrification within a thunderstorm, while the updraft also plays a critical role in the development of severe and hazardous weather. Therefore utilizing this relationship, the monitoring of <span class="hlt">lightning</span> rates and jumps provides an additional piece of information on the evolution of a thunderstorm, more often than not, at higher temporal resolution than current operational radar systems. This correlation is the basis for the total <span class="hlt">lightning</span> jump algorithm that has been developed in recent years. Currently, the <span class="hlt">lightning</span> jump algorithm is being <span class="hlt">tested</span> in two separate but important efforts. Schultz et al. (2014; this conference) is exploring the transition of the algorithm from its research based formulation to a fully objective algorithm that includes storm tracking, Geostationary <span class="hlt">Lightning</span> Mapper (GLM) Proxy data and the <span class="hlt">lightning</span> jump algorithm. Chronis et al. (2014) provides context for the transition to current operational forecasting using <span class="hlt">lightning</span> mapping array based products. However, what remains is an end-to-end physical and dynamical basis for coupling total <span class="hlt">lightning</span> flash rates to severe storm manifestation, so the forecaster has a reason beyond simple correlation to utilize the <span class="hlt">lightning</span> jump algorithm within their severe storm conceptual models. Therefore, the physical basis for the <span class="hlt">lightning</span> jump algorithm in relation to severe storm dynamics and microphysics is a key component that must be further explored. Many radar studies have examined flash rates and their relationship to updraft strength, updraft volume, precipitation-sized ice mass, etc.; however, their relationship specifically to <span class="hlt">lightning</span> jumps is fragmented within the literature. Thus the goal of this study is to use multiple Doppler and polarimetric</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('http://hdl.handle.net/2060/20140011607','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140011607"><span>Physical and Dynamical Linkages between <span class="hlt">Lightning</span> Jumps and Storm Conceptual Models</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.; Carey, Lawrence D.; Schultz, Elise V.; Blakeslee, Richard J.; Goodman, Steven J.</p> <p>2014-01-01</p> <p>The presence and rates of total <span class="hlt">lightning</span> are both correlated to and physically dependent upon storm updraft strength, mixed phase precipitation volume and the size of the charging zone. The updraft modulates the ingredients necessary for electrification within a thunderstorm, while the updraft also plays a critical role in the development of severe and hazardous weather. Therefore utilizing this relationship, the monitoring of <span class="hlt">lightning</span> rates and jumps provides an additional piece of information on the evolution of a thunderstorm, more often than not, at higher temporal resolution than current operational radar systems. This correlation is the basis for the total <span class="hlt">lightning</span> jump algorithm that has been developed in recent years. Currently, the <span class="hlt">lightning</span> jump algorithm is being <span class="hlt">tested</span> in two separate but important efforts. Schultz et al. (2014; this conference) is exploring the transition of the algorithm from its research based formulation to a fully objective algorithm that includes storm tracking, Geostationary <span class="hlt">Lightning</span> Mapper (GLM) Proxy data and the <span class="hlt">lightning</span> jump algorithm. Chronis et al. (2014; this conference) provides context for the transition to current operational forecasting using <span class="hlt">lightning</span> mapping array based products. However, what remains is an end-to-end physical and dynamical basis for coupling total <span class="hlt">lightning</span> flash rates to severe storm manifestation, so the forecaster has a reason beyond simple correlation to utilize the <span class="hlt">lightning</span> jump algorithm within their severe storm conceptual models. Therefore, the physical basis for the <span class="hlt">lightning</span> jump algorithm in relation to severe storm dynamics and microphysics is a key component that must be further explored. Many radar studies have examined flash rates and their relationship to updraft strength, updraft volume, precipitation-sized ice mass, etc.; however, their relationship specifically to <span class="hlt">lightning</span> jumps is fragmented within the literature. Thus the goal of this study is to use multiple Doppler and</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('http://hdl.handle.net/2060/20120003408','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120003408"><span>Objective <span class="hlt">Lightning</span> Probability Forecast Tool Phase II</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lambert, Winnie</p> <p>2007-01-01</p> <p>This presentation describes the improvement of a set of <span class="hlt">lightning</span> probability forecast equations that are used by the 45th Weather Squadron forecasters for their daily 1100 UTC (0700 EDT) weather briefing during the warm season months of May-September. This information is used for general scheduling of operations at Cape Canaveral Air Force Station and Kennedy Space Center. Forecasters at the Spaceflight Meteorology Group also make thunderstorm forecasts during Shuttle flight operations. Five modifications were made by the Applied Meteorology Unit: increased the period of record from 15 to 17 years, changed the method of calculating the flow regime of the day, calculated a new optimal layer relative humidity, used a new smoothing technique for the daily climatology, and used a new valid area. The <span class="hlt">test</span> results indicated that the modified equations showed and increase in skill over the current equations, good reliability, and an ability to distinguish between <span class="hlt">lightning</span> and non-<span class="hlt">lightning</span> days.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140006428','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140006428"><span>An Investigation of the Kinematic and Microphysical Control of <span class="hlt">Lightning</span> Rate, Extent and NOx Production using DC3 Observations and the NASA <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Carey, Lawrence; Koshak, William; Peterson, Harold; Matthee, Retha; Bain, Lamont</p> <p>2013-01-01</p> <p>The Deep Convective Clouds and Chemistry (DC3) experiment seeks to quantify the relationship between storm physics, <span class="hlt">lightning</span> characteristics and the production of nitrogen oxides via <span class="hlt">lightning</span> (LNOx). The focus of this study is to investigate the kinematic and microphysical control of <span class="hlt">lightning</span> properties, particularly those that may govern LNOx production, such as flash rate, type and extent across Alabama during DC3. Prior studies have demonstrated that <span class="hlt">lightning</span> flash rate and type is correlated to kinematic and microphysical properties in the mixed-phase region of thunderstorms such as updraft volume and graupel mass. More study is required to generalize these relationships in a wide variety of storm modes and meteorological conditions. Less is known about the co-evolving relationship between storm physics, morphology and three-dimensional flash extent, despite its importance for LNOx production. To address this conceptual gap, the NASA <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) is applied to North Alabama <span class="hlt">Lightning</span> Mapping Array (NALMA) and Vaisala National <span class="hlt">Lightning</span> Detection Network(TM) (NLDN) observations following ordinary convective cells through their lifecycle. LNOM provides estimates of flash rate, flash type, channel length distributions, <span class="hlt">lightning</span> segment altitude distributions (SADs) and <span class="hlt">lightning</span> NOx production profiles. For this study, LNOM is applied in a Lagrangian sense to multicell thunderstorms over Northern Alabama on two days during DC3 (21 May and 11 June 2012) in which aircraft observations of NOx are available for comparison. The LNOM <span class="hlt">lightning</span> characteristics and LNOX production estimates are compared to the evolution of updraft and precipitation properties inferred from dual-Doppler and polarimetric radar analyses applied to observations from a nearby radar network, including the UAH Advanced Radar for Meteorological and Operational Research (ARMOR). Given complex multicell evolution, particular attention is paid to storm morphology, cell</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140006435','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140006435"><span>An Investigation of the Kinematic and Microphysical Control of <span class="hlt">Lightning</span> Rate, Extent and NOX Production using DC3 Observations and the NASA <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Carey, Lawrence; Koshak, William; Peterson, Harold; Matthee, Retha; Bain, Lamont</p> <p>2013-01-01</p> <p>The Deep Convective Clouds and Chemistry (DC3) experiment seeks to quantify the relationship between storm physics, <span class="hlt">lightning</span> characteristics and the production of nitrogen oxides via <span class="hlt">lightning</span> (LNOx). The focus of this study is to investigate the kinematic and microphysical control of <span class="hlt">lightning</span> properties, particularly those that may govern LNOx production, such as flash rate, type and extent across Alabama during DC3. Prior studies have demonstrated that <span class="hlt">lightning</span> flash rate and type is correlated to kinematic and microphysical properties in the mixed-phase region of thunderstorms such as updraft volume and graupel mass. More study is required to generalize these relationships in a wide variety of storm modes and meteorological conditions. Less is known about the co-evolving relationship between storm physics, morphology and three-dimensional flash extent, despite its importance for LNOx production. To address this conceptual gap, the NASA <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) is applied to North Alabama <span class="hlt">Lightning</span> Mapping Array (NALMA) and Vaisala National <span class="hlt">Lightning</span> Detection NetworkTM (NLDN) observations following ordinary convective cells through their lifecycle. LNOM provides estimates of flash rate, flash type, channel length distributions, <span class="hlt">lightning</span> segment altitude distributions (SADs) and <span class="hlt">lightning</span> NOx production profiles. For this study, LNOM is applied in a Lagrangian sense to multicell thunderstorms over Northern Alabama on two days during DC3 (21 May and 11 June 2012) in which aircraft observations of NOx are available for comparison. The LNOM <span class="hlt">lightning</span> characteristics and LNOX production estimates are compared to the evolution of updraft and precipitation properties inferred from dual-Doppler and polarimetric radar analyses applied to observations from a nearby radar network, including the UAH Advanced Radar for Meteorological and Operational Research (ARMOR). Given complex multicell evolution, particular attention is paid to storm morphology, cell</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('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 laboratory <span class="hlt">tests</span> 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('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/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> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMAE33A0333D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMAE33A0333D"><span>ELF Sferics Produced by Rocket-Triggered <span class="hlt">Lightning</span> and Observed at Great Distances</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.; Fraser-Smith, A. C.</p> <p>2013-12-01</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 as a function of return stroke. Rocket-triggered <span class="hlt">lightning</span> experiments are performed at the International Center for <span class="hlt">Lightning</span> Research and <span class="hlt">Testing</span> (ICLRT) located at Camp Blanding, Florida. Long-distance ELF observations are performed in California, Greenland, and Antarctica, although this work focuses on observations performed in Greenland. The <span class="hlt">lightning</span> current waveforms directly measured at the base of the <span class="hlt">lightning</span> channel (at the ICLRT) are used together with the Long Wavelength Propagation Capability (LWPC) code to predict the sferic waveform observed at the receiver locations under various ionospheric conditions. LWPC was developed by the Naval Ocean Systems Center over a period of many years. It 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. This paper critically compares observations with model predictions, and in particular analyzes Earth-ionosphere waveguide excitation as a function of return stroke. The ability to infer source characteristics using observations at great distances may prove to greatly enhance the understanding of <span class="hlt">lightning</span> processes that are associated with the production of transient luminous events (TLEs) as well as other ionospheric effects associated with <span class="hlt">lightning</span>.</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('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('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('https://www.ncbi.nlm.nih.gov/pubmed/27328835','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27328835"><span>Relativistic-microwave theory of ball <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>Wu, H-C</p> <p>2016-06-22</p> <p>Ball <span class="hlt">lightning</span>, a fireball sometimes observed during <span class="hlt">lightnings</span>, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span>, such as the occurrence site, relation to the <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span> protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics.</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/2016NatSR...628263W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...628263W"><span>Relativistic-microwave theory of ball <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>Wu, H.-C.</p> <p>2016-06-01</p> <p>Ball <span class="hlt">lightning</span>, a fireball sometimes observed during <span class="hlt">lightnings</span>, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span>, such as the occurrence site, relation to the <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span> protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4916449','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4916449"><span>Relativistic-microwave theory of ball <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>Wu, H.-C.</p> <p>2016-01-01</p> <p>Ball <span class="hlt">lightning</span>, a fireball sometimes observed during <span class="hlt">lightnings</span>, has remained unexplained. Here we present a comprehensive theory for the phenomenon: At the tip of a <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span>, such as the occurrence site, relation to the <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span> protection and aviation safety, as well as stimulate research interest in the relativistic regime of microwave physics. PMID:27328835</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://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> <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('http://adsabs.harvard.edu/abs/2017EPJWC.16201065U','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EPJWC.16201065U"><span>Laboratory demonstration of <span class="hlt">lightning</span> strike pattern on different roof tops installed with Franklin Rods</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ullah, Irshad; Baharom, MNR; Ahmed, H.; Luqman, HM.; Zainal, Zainab</p> <p>2017-11-01</p> <p>Protection against <span class="hlt">lightning</span> is always a challenging job for the researcher. The consequences due to <span class="hlt">lightning</span> on different building shapes needs a comprehensive knowledge in order to provide the information to the common man. This paper is mainly concern with <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span> voltage. The equal distribution of <span class="hlt">lightning</span> voltage will provide the maximum probability of <span class="hlt">lightning</span> strike on air terminal of the selected shapes. Building shapes have a very important role in <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span> 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 <span class="hlt">tested</span> object is kept the same. This equal distribution of the <span class="hlt">lightning</span> voltage also proves that the probability of <span class="hlt">lightning</span> strike is on the corner and the edges of the building structure.</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://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://adsabs.harvard.edu/abs/1994JGR....9910679G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994JGR....9910679G"><span>Laboratory-produced ball <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>Golka, Robert K., Jr.</p> <p>1994-05-01</p> <p>For 25 years I have actively been searching for the true nature of ball <span class="hlt">lightning</span> and attempting to reproduce it at will in the laboratory. As one might expect, many unidentified lights in the atmosphere have been called ball <span class="hlt">lightning</span>, including Texas Maffa lights (automobile headlights), flying saucers (UFOs), swamp gas in Ann Arbor, Michigan, etc. For 15 years I thought ball <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span> 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.</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/2060/20080048096','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080048096"><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, Eugene W., Jr.; Goodman, Steven J.; LaCasse, Katherine M.; Cecil, Daniel J.</p> <p>2008-01-01</p> <p>Two new approaches are proposed and developed for making time and space dependent, quantitative short-term forecasts of <span class="hlt">lightning</span> threat, and a blend of these approaches is devised that capitalizes on the strengths of each. The new methods are distinctive in that they are based entirely on the ice-phase hydrometeor fields generated by regional cloud-resolving numerical simulations, such as those produced by the WRF model. These methods are justified by established observational evidence linking aspects of the precipitating ice hydrometeor fields to total flash rates. The methods are straightforward and easy to implement, and offer an effective near-term alternative to the incorporation of complex and costly cloud electrification schemes into numerical models. One method is based on upward fluxes of precipitating ice hydrometeors in the mixed phase region at the-15 C 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 domain-wide statistics of the peak values of simulated flash rate proxy fields against domain-wide peak total <span class="hlt">lightning</span> flash rate density data from observations. <span class="hlt">Tests</span> 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. Our blended solution is designed to retain most of the temporal sensitivity of the first method, while adding the improved spatial coverage of the second. Exploratory <span class="hlt">tests</span> for selected North Alabama cases show that, because WRF can distinguish the general character of most convective events, our methods show promise as a means of generating quantitatively realistic fields of <span class="hlt">lightning</span> threat. However, because the models tend to have more difficulty in predicting the instantaneous placement of storms, forecasts of the detailed location of the <span class="hlt">lightning</span> threat based on single</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://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('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 Laboratory 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://hdl.handle.net/2060/20110004347','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110004347"><span>The Goes-R Geostationary <span class="hlt">Lightning</span> Mapper (GLM): Algorithm and Instrument Status</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>2010-01-01</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. 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, 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 <span class="hlt">test</span> beds are being used to develop the pre-launch algorithms and applications, and also improve our knowledge of thunderstorm initiation and evolution. A joint field campaign with Brazilian researchers in 2010-2011 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> Imaging Sensor (LIS) overpasses, and related ground and in-situ <span class="hlt">lightning</span> and meteorological measurements in the vicinity of Sao Paulo. These data will provide a new comprehensive proxy data set for algorithm and</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://www.dtic.mil/docs/citations/ADA099590','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA099590"><span><span class="hlt">Lightning</span> Technology (Supplement)</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1981-01-01</p> <p>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 <span class="hlt">LIGHTNING</span> HARDENING MEASURES ON THE NAVY/AIR FORCE COMBAT MANEUVERING RANGES...overall <span class="hlt">lightning</span> event taken from an appropriate base of wideband measurements . In 1979, the Air Force Wright Aeronautical Laboratories began a joint</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> <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/29138444','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29138444"><span>The Elusive Evidence of Volcanic <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>Genareau, K; Gharghabi, P; Gafford, J; Mazzola, M</p> <p>2017-11-14</p> <p><span class="hlt">Lightning</span> strikes are known to morphologically alter and chemically reduce geologic formations and deposits, forming fulgurites. A similar process occurs as the result of volcanic <span class="hlt">lightning</span> discharge, when airborne volcanic ash is transformed into <span class="hlt">lightning</span>-induced volcanic spherules (LIVS). Here, we adapt the calculations used in previous studies of <span class="hlt">lightning</span>-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 <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span> during explosive eruptions.</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://hdl.handle.net/2060/20140011605','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140011605"><span>The Kinematic and Microphysical Control of <span class="hlt">Lightning</span> Rate, Extent and NOX Production</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Carey, Lawrence; Koshak, William; Peterson, Harold; Matthee, Retha; Bain, A. Lamont</p> <p>2014-01-01</p> <p>The Deep Convective Clouds and Chemistry (DC3) experiment seeks to quantify the relationship between storm physics, <span class="hlt">lightning</span> characteristics and the production of nitrogen oxides via <span class="hlt">lightning</span> (LNOx). The focus of this study is to investigate the kinematic and microphysical control of <span class="hlt">lightning</span> properties, particularly those that may govern LNOx production, such as flash rate, type and extent across Alabama during DC3. Prior studies have demonstrated that <span class="hlt">lightning</span> flash rate and type is correlated to kinematic and microphysical properties in the mixed-phase region of thunderstorms such as updraft volume and graupel mass. More study is required to generalize these relationships in a wide variety of storm modes and meteorological conditions. Less is known about the co-evolving relationship between storm physics, morphology and three-dimensional flash extent, despite its importance for LNOx production. To address this conceptual gap, the NASA <span class="hlt">Lightning</span> Nitrogen Oxides Model (LNOM) is applied to North Alabama <span class="hlt">Lightning</span> Mapping Array (NALMA) and Vaisala National <span class="hlt">Lightning</span> Detection Network(TM) (NLDN) observations following ordinary convective cells through their lifecycle. LNOM provides estimates of flash rate, flash type, channel length distributions, <span class="hlt">lightning</span> segment altitude distributions (SADs) and <span class="hlt">lightning</span> NOx production profiles. For this study, LNOM is applied in a Lagrangian sense to multicell thunderstorms over Northern Alabama on two days during DC3 (21 May and 11 June 2012) in which aircraft observations of NOx are available for comparison. The LNOM <span class="hlt">lightning</span> characteristics and LNOX production estimates are compared to the evolution of updraft and precipitation properties inferred from dual-Doppler and polarimetric radar analyses applied to observations from a nearby radar network, including the UAH Advanced Radar for Meteorological and Operational Research (ARMOR). Given complex multicell evolution, particular attention is paid to storm morphology, cell</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140011606','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140011606"><span>Variation of a <span class="hlt">Lightning</span> NOx Indicator for National Climate Assessment</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.; McCaul, Eugene W., Jr.; Peterson, Harold S.; Vant-Hull, Brian</p> <p>2014-01-01</p> <p>During the past couple of years, an analysis tool was developed by the NASA Marshall Space Flight Center (MSFC) for the National Climate Assessment (NCA) <span class="hlt">program</span>. The tool monitors and examines changes in <span class="hlt">lightning</span> characteristics over the conterminous US (CONUS) on a continual basis. In this study, we have expanded the capability of the tool so that it can compute a new climate assessment variable that is called the <span class="hlt">Lightning</span> NOx Indicator (LNI). Nitrogen oxides (NOx = NO + NO2) are known to indirectly influence our climate, and <span class="hlt">lightning</span> NOx is the most important source of NOx in the upper troposphere (particularly in the tropics). The LNI is derived using <span class="hlt">Lightning</span> Imaging Sensor (LIS) data and is computed by summing up the product of flash area x flash brightness over all flashes that occur in a particular region and period. Therefore, it is suggested that the LNI is a proxy to <span class="hlt">lightning</span> NOx production. Specifically, larger flash areas are consistent with longer channel length and/or more energetic channels, and hence more NOx production. Brighter flashes are consistent with more energetic channels, and hence more NOx production. The location of the flash within the thundercloud and the optical scattering characteristics of the thundercloud are of course complicating factors. We analyze LIS data for the years 2003-2013 and provide geographical plots of the time-evolution of the LNI in order to determine if there are any significant changes or trends between like seasons, or from year to year.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100040504','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100040504"><span>The Sao Paulo <span class="hlt">Lightning</span> Mapping Array (SPLMA): Prospects to GOES-R GLM and CHUVA</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Albrecht, Rachel I.; Carrey, Larry; Blakeslee, Richard J.; Bailey, Jeffrey C.; Goodman, Steven J.; Bruning, Eric C.; Koshak, William; Morales, Carlos A.; Machado, Luiz A. T.; Angelis, Carlos F.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20100040504'); toggleEditAbsImage('author_20100040504_show'); toggleEditAbsImage('author_20100040504_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20100040504_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20100040504_hide"></p> <p>2010-01-01</p> <p>This paper presents the characteristics and prospects of a <span class="hlt">Lightning</span> Mapping Array to be deployed at the city of S o Paulo (SPLMA). This LMA network will provide CHUVA campaign with total <span class="hlt">lightning</span>, <span class="hlt">lightning</span> channel mapping and detailed information on the locations of cloud charge regions for the thunderstorms investigated during one of its IOP. The real-time availability of LMA observations will also contribute to and support improved weather situational awareness and mission execution. For GOES-R <span class="hlt">program</span> it will form the basis of generating unique and valuable proxy data sets for both GLM and ABI sensors in support of several on-going research investigations</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('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('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> </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.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> <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('http://adsabs.harvard.edu/abs/2000GeoRL..27.1487M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000GeoRL..27.1487M"><span>Measurements of <span class="hlt">lightning</span> rod responses to nearby 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. B.; Aulich, G. D.; Rison, W.</p> <p>2000-05-01</p> <p>Following Benjamin Franklin's invention of the <span class="hlt">lightning</span> rod, based on his discovery that electrified objects could be discharged by approaching them with a metal needle in hand, conventional <span class="hlt">lightning</span> rods in the U.S. have had sharp tips. In recent years, the role of the sharp tip in causing a <span class="hlt">lightning</span> rod to act as a strike receptor has been questioned leading to experiments in which pairs of various sharp-tipped and blunt rods have been exposed beneath thunderclouds to determine the better strike receptor. After seven years of <span class="hlt">tests</span>, none of the sharp Franklin rods or of the so-called “early streamer emitters” has been struck, but 12 blunt rods with tip diameters ranging from 12.7 mm to 25.4 mm have taken strikes. Our field experiments and our analyses indicate that the strike-reception probabilities of Franklin's rods are greatly increased when their tips are made moderately blunt.</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://adsabs.harvard.edu/abs/2016EGUGA..18.4519F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.4519F"><span>Infrasound from <span class="hlt">lightning</span> measured in Ivory Coast from 2004 to 2014</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farges, Thomas; Le Pichon, Alexis; Ceranna, Lars; Diawara, Adama</p> <p>2016-04-01</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. 80 % of the infrasound stations of the International Monitoring System (IMS) of the CTBTO (Comprehensive nuclear <span class="hlt">Test</span> 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 <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. Assink et al. (2008) and Farges and Blanc (2010) show clearly that it is possible to measure <span class="hlt">lightning</span> infrasound from thunderstorms within 300 km. One-to-one correlation is possible when the thunderstorm is within about 75 km from the station. When the <span class="hlt">lightning</span> flash occurs within 20 km, it is also possible to rebuild the 3D geometry of the discharges when the network size is less than 100 m (Arechiga et al., 2011; Gallin, 2014). An IMS infrasound station has been installed in Ivory Coast since 2002. 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 10 years of data (2005-2014). Correlation between infrasound having a mean frequency higher than 1 Hz and <span class="hlt">lightning</span> flashes detected by the World Wide <span class="hlt">Lightning</span> Location Network (WWLLN) is systematically looked for. One-to-one correlation is obtained for flashes occurring within about 100 km. An exponential decrease of the</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('http://hdl.handle.net/2060/20150001257','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150001257"><span>Open Circuit Resonant (SansEC) Sensor Technology for <span class="hlt">Lightning</span> Mitigation and Damage Detection and Diagnosis for Composite Aircraft Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Szatkowski, George N.; Dudley, Kenneth L.; Smith, Laura J.; Wang, Chuantong; Ticatch, Larry A.</p> <p>2014-01-01</p> <p> aircraft composite damage detection and diagnosis. Experimental <span class="hlt">test</span> results on seeded fault damage coupons and computational modeling simulation results are presented. This paper also presents the shielding effectiveness along with the <span class="hlt">lightning</span> direct effect <span class="hlt">test</span> results from several different SansEC LSP and baseline protected and unprotected carbon fiber reinforced polymer (CFRP) <span class="hlt">test</span> panels struck at 40 and 100 kiloamperes following a universal common practice <span class="hlt">test</span> procedure to enable damage comparisons between SansEC LSP configurations and common practice copper mesh LSP approaches. The SansEC <span class="hlt">test</span> panels were mounted in a LSP <span class="hlt">test</span> bed during the <span class="hlt">lightning</span> <span class="hlt">test</span>. Electrical, mechanical and thermal parameters were measured during <span class="hlt">lightning</span> attachment and are presented with post <span class="hlt">test</span> nondestructive inspection comparisons. The paper provides correlational results between the SansEC sensors computed electric field distribution and the location of the <span class="hlt">lightning</span> attachment on the sensor trace and visual observations showing the SansEC sensor's affinity for dispersing the <span class="hlt">lightning</span> attachment.</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://www.ncbi.nlm.nih.gov/pubmed/28269072','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28269072"><span>Development of a head-phantom and measurement setup for <span class="hlt">lightning</span> effects.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Machts, Rene; Hunold, Alexander; Leu, Carsten; Haueisen, Jens; Rock, Michael</p> <p>2016-08-01</p> <p>Direct <span class="hlt">lightning</span> strikes to human heads lead to various effects ranging from Lichtenberg figures, over loss of consciousness to death. The evolution of the induced current distribution in the head is of great interest to understand the effect mechanisms. This work describes a technique to model a simplified head-phantom to investigate effects during direct <span class="hlt">lightning</span> strike. The head-phantom geometry, conductive and dielectric parameters were chosen similar to that of a human head. Three layers (brain, skull, and scalp) were created for the phantom using agarose hydrogel doped with sodium chloride and carbon. The head-phantom was <span class="hlt">tested</span> on two different impulse generators, which reproduce approximate <span class="hlt">lightning</span> impulses. The effective current and the current distribution in each layer were analyzed. The biggest part of the current flowed through the brain layer, approx. 70 % in cases without external flashover. Approx. 23 % of the current flowed through skull layer and 6 % through the scalp layer. However, the current decreased within the head-phantom to almost zero after a complete flashover on the phantom occurred. The flashover formed faster with a higher impulse current level. Exposition time of current through the head decreases with a higher current level of the <span class="hlt">lightning</span> impulse. This mechanism might explain the fact that people can survive a <span class="hlt">lightning</span> strike. The experiments help to understand <span class="hlt">lightning</span> effects on humans.</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.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/2060/19840019308','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840019308"><span>Data and results of a laboratory 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 <span class="hlt">tests</span> 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 <span class="hlt">program</span> code on the microprocessor during <span class="hlt">tests</span> 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/2060/20150001382','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/2060/20150022939','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('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_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('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('http://hdl.handle.net/2060/20140006442','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140006442"><span>Analytic Perturbation Method for Estimating Ground Flash Fraction from Satellite <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>Koshak, William; Solakiewicz, Richard</p> <p>2013-01-01</p> <p>An analytic perturbation method is introduced for estimating the <span class="hlt">lightning</span> ground flash fraction in a set of N <span class="hlt">lightning</span> flashes observed by a satellite <span class="hlt">lightning</span> mapper. The value of N is large, typically in the thousands, and the observations consist of the maximum optical group area produced by each flash. The method is <span class="hlt">tested</span> using simulated observations that are based on Optical Transient Detector (OTD) and <span class="hlt">Lightning</span> Imaging Sensor (LIS) data. National <span class="hlt">Lightning</span> Detection NetworkTM (NLDN) data is used to determine the flash-type (ground or cloud) of the satellite-observed flashes, and provides the ground flash fraction truth for the simulation runs. It is found that the mean ground flash fraction retrieval errors are below 0.04 across the full range 0-1 under certain simulation conditions. In general, it is demonstrated that the retrieval errors depend on many factors (i.e., the number, N, of satellite observations, the magnitude of random and systematic measurement errors, and the number of samples used to form certain climate distributions employed in the model).</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('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('http://hdl.handle.net/2060/20150002882','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150002882"><span>Cloud-to-Ground <span class="hlt">Lightning</span> Estimates Derived from SSMI Microwave Remote Sensing and NLDN</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Winesett, Thomas; Magi, Brian; Cecil, Daniel</p> <p>2015-01-01</p> <p> present in the cloud and electric charge separation occurs. These ice particles efficiently scatter the microwave radiation at the 85 and 37 GHz frequencies, thus leading to large brightness temperature depressions. <span class="hlt">Lightning</span> flash rate is related to the total amount of ice passing through the convective updraft regions of thunderstorms. Confirmation of this relationship using TRMM LIS and TMI data, however, remains constrained to TRMM observational limits of the tropics and subtropics. Satellites from the Defense Meteorology Satellite <span class="hlt">Program</span> (DMSP) have global coverage and are equipped with passive microwave imagers that, like TMI, observe brightness temperatures at 85 and 37 GHz. Unlike the TRMM satellite, however, DMSP satellites do not have a <span class="hlt">lightning</span> sensor, and the DMSP microwave data has never been used to derive global <span class="hlt">lightning</span>. In this presentation, a relationship between DMSP Special Sensor Microwave Imager (SSMI) data and ground-based cloud-to-ground (CG) <span class="hlt">lightning</span> data from NLDN is investigated to derive a spatially complete time history of CG <span class="hlt">lightning</span> for the USA study area. This relationship is analogous to the established using TRMM LIS and TMI data. NLDN has the most spatially and temporally complete CG <span class="hlt">lightning</span> data for the USA, and therefore provides the best opportunity to find geospatially coincident observations with SSMI sensors. The strongest thunderstorms generally have minimum 85 GHz Polarized Corrected brightness Temperatures (PCT) less than 150 K. Archived radar data was used to resolve the spatial extent of the individual storms. NLDN data for that storm spatial extent defined by radar data was used to calculate the CG flash rate for the storm. Similar to results using TRMM sensors, a linear model best explained the relationship between storm-specific CG flash rates and minimum 85 GHz PCT. However, the results in this study apply only to CG <span class="hlt">lightning</span>. To extend the results to weaker storms, the probability of CG <span class="hlt">lightning</span> (instead of the</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://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 laboratories 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('https://www.ncbi.nlm.nih.gov/pubmed/21778092','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21778092"><span><span class="hlt">Lightning</span> safety awareness of visitors in three California national parks.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Weichenthal, Lori; Allen, Jacoby; Davis, Kyle P; Campagne, Danielle; Snowden, Brandy; Hughes, Susan</p> <p>2011-09-01</p> <p>To assess the level of <span class="hlt">lightning</span> safety awareness among visitors at 3 national parks in the Sierra Nevada Mountains of California. A 12-question, short answer convenience sample survey was administered to participants 18 years of age and over concerning popular trails and points of interest with known <span class="hlt">lightning</span> activity. There were 6 identifying questions and 5 knowledge-based questions pertaining to <span class="hlt">lightning</span> that were scored on a binary value of 0 or 1 for a total of 10 points for the survey instrument. Volunteers in Fresno, California, were used as a control group. Participants were categorized as Sequoia and Kings Canyon National Park (SEKI), frontcountry (FC), or backcountry (BC); Yosemite National Park (YNP) FC or BC; and Fresno. Analysis of variance (ANOVA) was used to <span class="hlt">test</span> for differences between groups. 467 surveys were included for analysis: 77 in Fresno, 192 in SEKI, and 198 in YNP. National park participants demonstrated greater familiarity with <span class="hlt">lightning</span> safety than individuals from the metropolitan community (YNP 5.84 and SEKI 5.65 vs Fresno 5.14, P = .0032). There were also differences noted between the BC and FC subgroups (YNP FC 6.07 vs YNP BC 5.62, P = .02; YNP FC 6.07 vs SEKI FC 5.58, P = .02). Overall results showed that participants had certain basic <span class="hlt">lightning</span> knowledge but lacked familiarity with other key <span class="hlt">lightning</span> safety recommendations. While there are statistically significant differences in <span class="hlt">lightning</span> safety awareness between national parks and metropolitan participants, the clinical impact of these findings are debatable. This study provides a starting point for providing educational outreach to visitors in these national parks. Copyright © 2011 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.</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('http://adsabs.harvard.edu/abs/2016AGUFM.A43H0340R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A43H0340R"><span>The Impact of <span class="hlt">Lightning</span> on Hurricane Rapid Intensification Forecasts Using the HWRF Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rosado, K.; Tallapragada, V.; Jenkins, G. S.</p> <p>2016-12-01</p> <p>In 2010, the National Oceanic and Atmospheric Administration (NOAA) created the Hurricane Forecast Improvement Project (HFIP) with the main goal of improving the tropical cyclone intensity and track forecasts by 50% in ten years. One of the focus areas is the improvement of the tropical cyclone rapid intensification (RI) forecasts. In order to contribute to this task, the role of <span class="hlt">lightning</span> during the life cycle of a tropical cyclone using the NCEP operational HWRF hurricane model has been investigated. We ask two key research questions: (1) What is the functional relationship between atmospheric moisture content, <span class="hlt">lightning</span>, and intensity in the HWRF model? and (2) How well does the HWRF model forecast the spatial distributions of <span class="hlt">lightning</span> before, during, and after tropical cyclone intensification, especially for RI events? In order to address those questions, a <span class="hlt">lightning</span> parameterization scheme called the <span class="hlt">Lightning</span> Potential Index (LPI) was implemented into the HWRF model. The selected study cases to <span class="hlt">test</span> the LPI implementation on the 2015 HWRF (operational version) are: Earl and Joaquin (North Atlantic), Haiyan (Western North Pacific), and Patricia (Eastern North Pacific). Five-day forecasts was executed on each case study with emphasis on rapid intensification periods. An extensive analysis between observed "best track" intensity, model intensity forecast, and potential for <span class="hlt">lightning</span> forecast was performed. Preliminary results show that: (1) strong correlation between <span class="hlt">lightning</span> and intensity changes does exists; and (2) the potential for <span class="hlt">lightning</span> increases to its maximum peak a few hours prior to the peak intensity of the tropical cyclone. LPI peak values could potentially serve as indicator for future rapid intensification periods. Results from this investigation are giving us a better understanding of the mechanism behind <span class="hlt">lightning</span> as a proxy for tropical cyclone steady state intensification and tropical cyclone rapid intensification processes. Improvement of</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://www.dtic.mil/docs/citations/ADA222716','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA222716"><span>Aircraft <span class="hlt">Lightning</span> Protection Handbook</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1989-09-01</p> <p>tape or metal braid . The shield. The effect of leakage through the connector can transfer characteristics can seldom be determined by thus be...62 REFERENCES 66 CHAPTER 4 <span class="hlt">LIGHTNING</span> EFFECTS ON AIRCRAFT 69 4.1 Introduction 69 4.2 Direct Effects on Metal Structures 70 4.2.1 Pitting and Melt...Certification plans 112 5.8 <span class="hlt">Test</span> Plans 113 REFERENCES 113 Chapter 6 DIRECT EFFECTS PROTECTION 115 6.1 Introduction 115 6.2 Direct Effects on Metal Structures</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('https://ntrs.nasa.gov/search.jsp?R=20040082320&hterms=can+tornado&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcan%2Bu%2Btornado%253F','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040082320&hterms=can+tornado&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcan%2Bu%2Btornado%253F"><span>The LATEST Project: Operational Assessment of Total <span class="hlt">Lightning</span> Data in the U.S.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodman, Steven</p> <p>2004-01-01</p> <p>A government, university, and industry alliance has joined forces to transition total <span class="hlt">lightning</span> observations from ground-based research networks and NASA satellites (LIS/TRMM) to improve the short range prediction of severe weather. This interest builds on the desire of the U.S Weather Research <span class="hlt">Program</span> to foster a national Nowcasting <span class="hlt">Test</span> Bed, with this specific transition activity initiated through the NASA short-term Prediction Research and Transition (SPoRT) Center in Huntsville, AL. A kick-off national workshop sponsored by the SPoRT Center was held in Huntsville April 1-2 to identify the common goals and objectives of the research and operational community, and to assign roles and responsibilities within the alliance. The workshop agenda, presentations, and summary are available at the SPoRT Center Web site ( h h under the "Meetings" tab. The next national workshop is planned for 2005 in Dallas, TX. The NASA North Alabama regional <span class="hlt">Lightning</span> Mapping Array &MA) has been operational in the Huntsville area for 3 years, and has continuously sampled a variety of severe weather systems during that period. A gridded version of the LMA total <span class="hlt">lightning</span> data is currently being supplied to National Weather Service offices in Huntsville, Nashville and Birmingham through the NWS AWES decision support system, for the purposes of assessing the utility of the data in the nowcasting of severe weather such as tornadoes, damaging straight line winds, flash flooding and other weather hazards (<span class="hlt">lightning</span> induced forest fires, microbursts). While the raw LMA data have been useful to NWS forecasters, even greater utility would be realized if higher-order data products could be supplied through AWIPS along with the gridded data over a larger domain. In 2003-2004 additional LMA systems have been deployed across the southern US. from Florida to New Mexico, providing an opportunity for more than 20 NWS forecast offices to evaluate the incremental value of total <span class="hlt">lightning</span> data in the</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://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('http://hdl.handle.net/2060/19790072484','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790072484"><span>Review of the <span class="hlt">Lightning</span> Strike Incident at Launch Complex 37 on July 27, 1967, and Comparison to a Gemini <span class="hlt">Lightning</span> Strike</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Llewellyn, J. A.</p> <p>1967-01-01</p> <p>The Launch Complex 37 <span class="hlt">lightning</span> strike of July 27, 1967, was reviewed and compared to a similar incident on the Gemini <span class="hlt">Program</span>. Available data indicate little likelihood of damaging currents having been present in SA-204 Launch Vehicle or the ground equipment during the July 27th incident. Based on the results of subsystem and system <span class="hlt">testing</span> after the strike, anticipated results of future <span class="hlt">testing</span>, the six months elapsed time between the strike-and launch, and the fact that much of the critical airborne electrical/electronic equipment has been removed since the strike for other reasons, no new actions are considered necessary at this time in the Gemini case, significant failures occurred in both airborne and ground circuits. Due to the resultant semi, condlictor uncertainty, and the relatively' short time prior to planned launch, all critical airborne components containing semiconduetors were replaced, and a sophisticated data comparison task was implemented.</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.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/2014AGUFMGC33D0547C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC33D0547C"><span>Using High Resolution Model Data to Improve <span class="hlt">Lightning</span> Forecasts across Southern California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Capps, S. B.; Rolinski, T.</p> <p>2014-12-01</p> <p>Dry <span class="hlt">lightning</span> often results in a significant amount of fire starts in areas where the vegetation is dry and continuous. Meteorologists from the USDA Forest Service Predictive Services' <span class="hlt">program</span> in Riverside, California are tasked to provide southern and central California's fire agencies with fire potential outlooks. Logistic regression equations were developed by these meteorologists several years ago, which forecast probabilities of <span class="hlt">lightning</span> as well as <span class="hlt">lightning</span> amounts, out to seven days across southern California. These regression equations were developed using ten years of historical gridded data from the Global Forecast System (GFS) model on a coarse scale (0.5 degree resolution), correlated with historical <span class="hlt">lightning</span> strike data. These equations do a reasonably good job of capturing a <span class="hlt">lightning</span> episode (3-5 consecutive days or greater of <span class="hlt">lightning</span>), but perform poorly regarding more detailed information such as exact location and amounts. It is postulated that the inadequacies in resolving the finer details of episodic <span class="hlt">lightning</span> events is due to the coarse resolution of the GFS data, along with limited predictors. Stability parameters, such as the Lifted Index (LI), the Total Totals index (TT), Convective Available Potential Energy (CAPE), along with Precipitable Water (PW) are the only parameters being considered as predictors. It is hypothesized that the statistical forecasts will benefit from higher resolution data both in training and implementing the statistical model. We have dynamically downscaled NCEP FNL (Final) reanalysis data using the Weather Research and Forecasting model (WRF) to 3km spatial and hourly temporal resolution across a decade. This dataset will be used to evaluate the contribution to the success of the statistical model of additional predictors in higher vertical, spatial and temporal resolution. If successful, we will implement an operational dynamically downscaled GFS forecast product to generate predictors for the resulting</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMAE21A0229D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMAE21A0229D"><span>Comparison between model predictions and observations of ELF radio atmospherics generated 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.</p> <p>2011-12-01</p> <p>Model predictions of the ELF radio atmospheric generated by rocket-triggered <span class="hlt">lightning</span> are compared with observations performed at Arrival Heights, Antarctica. The ability to infer source characteristics using observations at great distances may prove to greatly enhance the understanding of <span class="hlt">lightning</span> processes that are associated with the production of transient luminous events (TLEs) as well as other ionospheric effects associated with <span class="hlt">lightning</span>. The modeling of the sferic waveform is carried out using a modified version of the Long Wavelength Propagation Capability (LWPC) code developed by the Naval Ocean Systems Center over a period of many years. 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. ELF observations performed at Arrival Heights, Antarctica during rocket-triggered <span class="hlt">lightning</span> experiments at the International Center for <span class="hlt">Lightning</span> Research and <span class="hlt">Testing</span> (ICLRT) located at Camp Blanding, Florida are presented. The <span class="hlt">lightning</span> current waveforms directly measured at the base of the <span class="hlt">lightning</span> channel (at the ICLRT) are used together with LWPC to predict the sferic waveform observed at Arrival Heights under various ionospheric conditions. This paper critically compares observations with model predictions.</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('http://adsabs.harvard.edu/abs/2010JGRA..115.0E31F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JGRA..115.0E31F"><span>Characteristics of infrasound from <span class="hlt">lightning</span> and sprites near thunderstorm areas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farges, Thomas; Blanc, Elisabeth</p> <p>2010-06-01</p> <p>Research about thunder was mainly performed 20-30 years ago but has been renewed in recent years due to new interest about infrasound in the framework of the verification of the compliance of the Comprehensive Nuclear-<span class="hlt">Test</span>-Ban Treaty. During the Eurosprite 2005 campaign, an infrasound miniarray has been set up in France to measure the characteristics of infrasound from <span class="hlt">lightning</span> and sprites when these kinds of sources were close to the sensors (that is, for <span class="hlt">lightning</span> distances lower than 100 km and sprite distances lower than 300 km). For two large thunderstorms which passed over the station, detection conditions of infrasound from <span class="hlt">lightning</span> are detailed, and some characteristics are thoroughly described (e.g., amplitude variation with distance and spectrum of an individual event in the frequency range from 0.01 to 10 Hz). The locations of infrasound sources are determined using a 3-D inversion. Infrasound signals from sprites have also been detected, and the 3-D inversion method used for <span class="hlt">lightning</span> infrasound has been adapted to locate the sources of infrasound from sprites. Four different sprite infrasound events are analyzed in this way. The infrasound source corresponds well to the sprite spatial characteristics deduced from camera observations. Questions about generation mechanisms of infrasound from <span class="hlt">lightning</span> and sprites still remain. These new results should help us to understand the sound generation processes.</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/2060/19750014262','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750014262"><span><span class="hlt">Lightning</span> effects on the NASA F-8 digital-fly-by-wire airplane</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.; Fisher, F. A.; Walko, L. C.</p> <p>1975-01-01</p> <p>The effects of <span class="hlt">lightning</span> on a Digital Fly-By-Wire (DFBW)aircraft control system were investigated. The aircraft was a NASA operated F-8 fitted with a modified Apollo guidance computer. Current pulses similar in waveshape to natural <span class="hlt">lightning</span>, but lower in amplitude, were injected into the aircraft. Measurements were made of the voltages induced on the DFBW circuits, the total current induced on the bundles of wires, the magnetic field intensity inside the aircraft, and the current density on the skin of the aircraft. Voltage measurements were made in both the line-to-ground and line-to-line modes. Voltages measured at the non-destructive <span class="hlt">test</span> level were then scaled upward to determine how much would be produced by actual <span class="hlt">lightning</span>. A 200,000 ampere severe <span class="hlt">lightning</span> flash would produce between 40 and 2000 volts in DFBW circuits. Some system components are expected to be vulnerable to these voltages.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20100002097&hterms=fractions&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dfractions','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20100002097&hterms=fractions&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dfractions"><span>A Method for Retrieving Ground Flash Fraction from Satellite <span class="hlt">Lightning</span> Imager Data</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>2009-01-01</p> <p>A general theory for retrieving the fraction of ground flashes in N <span class="hlt">lightning</span> observed by a satellite-based <span class="hlt">lightning</span> imager is provided. An "exponential model" is applied as a physically reasonable constraint to describe the measured optical parameter distributions, and population statistics (i.e., mean, variance) are invoked to add additional constraints to the retrieval process. The retrieval itself is expressed in terms of a Bayesian inference, and the Maximum A Posteriori (MAP) solution is obtained. The approach is <span class="hlt">tested</span> by performing simulated retrievals, and retrieval error statistics are provided. The ability to retrieve ground flash fraction has important benefits to the atmospheric chemistry community. For example, using the method to partition the existing satellite global <span class="hlt">lightning</span> climatology into separate ground and cloud flash climatologies will improve estimates of <span class="hlt">lightning</span> nitrogen oxides (NOx) production; this in turn will improve both regional air quality and global chemistry/climate model predictions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1985lse..conf......','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1985lse..conf......"><span>International Aerospace and Ground Conference on <span class="hlt">Lightning</span> and Static Electricity, 10th, and Congres International Aeronautique, 17th, Paris, France, June 10-13, 1985, Proceedings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p></p> <p>1985-12-01</p> <p>The conference presents papers on statistical data and standards, coupling and indirect effects, meteorology and thunderstorm studies, <span class="hlt">lightning</span> simulators, fuel ignition hazards, the phenomenology and characterization of <span class="hlt">lightning</span>, susceptibility and protection of avionics, ground systems protection, <span class="hlt">lightning</span> locators, aircraft systems protection, structures and materials, electrostatics, and spacecraft protection against static electricity. Particular attention is given to a comparison of published HEMP and natural <span class="hlt">lightning</span> on the surface of an aircraft, electromagnetic interaction of external impulse fields with aircraft, of thunderstorm currents and <span class="hlt">lightning</span> charges at the NASA Kennedy Space Center, the design of a fast risetime <span class="hlt">lightning</span> generator, <span class="hlt">lightning</span> simulation <span class="hlt">tests</span> in FAA CV-580 <span class="hlt">lightning</span> research aircraft, and the energy requirements of an aircraft triggered discharge. Papers are also presented on aircraft <span class="hlt">lightning</span> attachment at low altitudes, a new form of transient suppressor, a proving ground for <span class="hlt">lightning</span> research, and a spacecraft materials <span class="hlt">test</span> in a continuous, broad energy-spectrum electron beam.</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://hdl.handle.net/2060/20150002890','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150002890"><span>Kinematic and Microphysical Control of <span class="hlt">Lightning</span> Flash Rate over Northern Alabama</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Carey, Lawrence D.; Bain, Anthony L.; Matthee, Retha; Schultz, Christopher J.; Schultz, Elise V.; Deierling, Wiebke; Petersen, Walter A.</p> <p>2015-01-01</p> <p>The Deep Convective Clouds and Chemistry (DC3) experiment seeks to examine the relationship between deep convection and the production of nitrogen oxides (NO (sub x)) via <span class="hlt">lightning</span> (LNO (sub x)). A critical step in estimating LNO (sub x) production in a cloud-resolving model (CRM) without explicit <span class="hlt">lightning</span> is to estimate the flash rate from available model parameters that are statistically and physically correlated. As such, the objective of this study is to develop, improve and evaluate <span class="hlt">lightning</span> flash rate parameterizations in a variety of meteorological environments and storm types using radar and <span class="hlt">lightning</span> mapping array (LMA) observations taken over Northern Alabama from 2005-2012, including during DC3. UAH's Advanced Radar for Meteorological and Operational Research (ARMOR) and the Weather Surveillance Radar - 1988 Doppler (WSR 88D) located at Hytop (KHTX) comprises the dual-Doppler and polarimetric radar network, which has been in operation since 2004. The northern Alabama LMA (NA LMA) in conjunction with Vaisala's National <span class="hlt">Lightning</span> Detection Network (NLDN) allow for a detailed depiction of total <span class="hlt">lightning</span> during this period. This study will integrate ARMOR-KHTX dual Doppler/polarimetric radar and NA LMA <span class="hlt">lightning</span> observations from past and ongoing studies, including the more recent DC3 results, over northern Alabama to form a large data set of 15-20 case days and over 20 individual storms, including both ordinary multicell and supercell convection. Several flash rate parameterizations will be developed and <span class="hlt">tested</span>, including those based on 1) graupel/small hail volume; 2) graupel/small hail mass, and 3) convective updraft volume. Sensitivity of the flash rate parameterizations to storm intensity, storm morphology and environmental conditions will be explored.</p> </li> <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 Laboratory, 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> </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://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('http://adsabs.harvard.edu/abs/2016RScI...87f3505K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016RScI...87f3505K"><span>Pulse generator with intermediate inductive storage as a <span class="hlt">lightning</span> simulator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kovalchuk, B. M.; Kharlov, A. V.; Zherlytsyn, A. A.; Kumpyak, E. V.; Tsoy, N. V.</p> <p>2016-06-01</p> <p>Compact transportable generators are required for simulating a <span class="hlt">lightning</span> current pulse for electrical apparatus <span class="hlt">testing</span>. A bi-exponential current pulse has to be formed by such a generator (with a current rise time of about two orders of magnitude faster than the damping time). The objective of this study was to develop and investigate a compact pulse generator with intermediate inductive storage and a fuse opening switch as a simulator of <span class="hlt">lightning</span> discharge. A Marx generator (six stages) with a capacitance of 1 μF and an output voltage of 240 kV was employed as primary storage. In each of the stages, two IK-50/3 (50 kV, 3 μF) capacitors are connected in parallel. The generator inductance is 2 μH. A <span class="hlt">test</span> bed for the investigations was assembled with this generator. The generator operates without SF6 and without oil in atmospheric air, which is very important in practice. Straight copper wires with adjustable lengths and diameters were used for the electro-explosive opening switch. <span class="hlt">Tests</span> were made with active-inductive loads (up to 0.1 Ω and up to 6.3 μH). The current rise time is lower than 1200 ns, and the damping time can be varied from 35 to 125 μs, following the definition of standard <span class="hlt">lightning</span> current pulse in the IEC standard. Moreover, 1D MHD calculations of the fuse explosion were carried out self-consistently with the electric circuit equations, in order to calculate more accurately the load pulse parameters. The calculations agree fairly well with the <span class="hlt">tests</span>. On the basis of the obtained results, the design of a transportable generator was developed for a <span class="hlt">lightning</span> simulator with current of 50 kA and a pulse shape corresponding to the IEEE standard.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21208587-packaging-waste-hitting-home-runs-how-education-lightning-strike-detection-technology-supports-company-community-activities','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21208587-packaging-waste-hitting-home-runs-how-education-lightning-strike-detection-technology-supports-company-community-activities"><span>Packaging Waste and Hitting Home Runs: How Education and <span class="hlt">Lightning</span> Strike Detection Technology Supports Company and Community Activities</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>Deecke, T.A.; Hyde, J.V.; Hylko, J.M.</p> <p>2006-07-01</p> <p>The weather is the most significant and unmanageable variable when performing environmental remediation activities. This variable can contribute to the failure of a project in two ways: 1) severe injury to an employee or employees following a cloud-to-ground <span class="hlt">lightning</span> strike without prior visual or audible warnings; and 2) excessive 'down time' associated with mobilization and demobilization activities after a false alarm (e.g., <span class="hlt">lightning</span> was seen in the distance but was actually moving away from the site). Therefore, in order for a project to be successful from both safety and financial viewpoints, the uncertainties associated with inclement weather, specifically <span class="hlt">lightning</span>, needmore » to be understood to eliminate the element of surprise. This paper discusses educational information related to the history and research of <span class="hlt">lightning</span>, how <span class="hlt">lightning</span> storms develop, types of <span class="hlt">lightning</span>, the mechanisms of <span class="hlt">lightning</span> injuries and fatalities, and follow-up medical treatment. Fortunately, <span class="hlt">lightning</span> storm monitoring does not have to be either costly or elaborate. WESKEM, LLC selected the Boltek StormTracker <span class="hlt">Lightning</span> Detection System with the Aninoquisi <span class="hlt">Lightning</span> 2000{sup TM} software. This fixed system, used in combination with online weather web pages, monitors and alarms WESKEM, LLC field personnel in the event of an approaching <span class="hlt">lightning</span> storm. This application was expanded to justify the purchase of the hand-held Sky Scan <span class="hlt">Lightning</span>/Storm Detector Model P5 used by the Heath Youth Athletic Association (HYAA) which is a non-profit, charitable organization offering sports <span class="hlt">programs</span> for the youth and young adults in the local community. Fortunately, a <span class="hlt">lightning</span> injury or fatality has never occurred on a WESKEM Paducah project or an HYAA-sponsored event. Using these fixed and hand-held systems will continue to prevent such injuries from occurring in the foreseeable future. (authors)« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110014829','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110014829"><span>Evaluation of <span class="hlt">Lightning</span> Induced Effects in a Graphite Composite Fairing Structure</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Trout, Dawn H.; Stanley, James E.; Wahid, Parveen F.</p> <p>2011-01-01</p> <p>Defining the electromagnetic environment inside a graphite composite fairing due to near-by <span class="hlt">lightning</span> strikes is of interest to spacecraft developers. This effort develops a transmission-line-matrix (TLM) model with a CST Microstripes to examine induced voltages. on interior wire loops in a composite fairing due to a simulated near-by <span class="hlt">lightning</span> strike. A physical vehicle-like composite fairing <span class="hlt">test</span> fixture is constructed to anchor a TLM model in the time domain and a FEKO method of moments model in the frequency domain. Results show that a typical graphite composite fairing provides adequate shielding resulting in a significant reduction in induced voltages on high impedance circuits despite minimal attenuation of peak magnetic fields propagating through space in near-by <span class="hlt">lightning</span> strike conditions.</p> </li> <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('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.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=522088','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=522088"><span>Isolation of <span class="hlt">Lightning</span>-Competent Soil Bacteria</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>2004-01-01</p> <p>Artificial transformation is typically performed in the laboratory by using either a chemical (CaCl2) or an electrical (electroporation) method. However, laboratory-scale <span class="hlt">lightning</span> has been shown recently to electrotransform Escherichia coli strain DH10B in soil. In this paper, we report on the isolation of two “<span class="hlt">lightning</span>-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 <span class="hlt">lightning</span> 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 <span class="hlt">lightning</span>, while no transformation was observed in the absence of electrical current. Two of the isolated <span class="hlt">lightning</span>-competent soil bacteria were identified as Pseudomonas sp. strains. PMID:15466589</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002GeoRL..29.1031P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002GeoRL..29.1031P"><span>An improved ELF/VLF method for globally geolocating sprite-producing <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>Price, Colin; Asfur, Mustafa; Lyons, Walter; Nelson, Thomas</p> <p>2002-02-01</p> <p>The majority of sprites, the most common of transient luminous events (TLEs) in the upper atmosphere, are associated with a sub-class of positive cloud-to-ground <span class="hlt">lightning</span> flashes (+CGs) whose characteristics are slowly being revealed. These +CGs produce extremely low frequency (ELF) and very low frequency (VLF) radiation detectable at great distances from the parent thunderstorm. During the STEPS field <span class="hlt">program</span> in the United States, ELF/VLF transients associated with sprites were detected in the Negev Desert, Israel, some 11,000 km away. Within a two-hour period on 4 July 2000, all of the sprites detected optically in the United States produced detectable ELF/VLF transients in Israel. All of these transients were of positive polarity (representing positive <span class="hlt">lightning</span>). Using the VLF data to obtain the azimuth of the transients, and the ELF data to calculate the distance between the source and receiver, we remotely determined the position of the sprite-forming <span class="hlt">lightning</span> with an average locational error of 184 km (error of 1.6%).</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/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/2060/19910010714','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 laboratory 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 <span class="hlt">program</span> 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> <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/2060/20070004930','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20070004930"><span>Objective <span class="hlt">Lightning</span> Probability Forecasting for Kennedy Space Center and Cape Canaveral Air Force Station</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>2005-01-01</p> <p>Five logistic regression equations were created that predict the probability of cloud-to-ground <span class="hlt">lightning</span> occurrence for the day in the KSC/CCAFS area for each month in the warm season. These equations integrated the results from several studies over recent years to improve thunderstorm forecasting at KSC/CCAFS. All of the equations outperform persistence, which is known to outperform NPTI, the current objective tool used in 45 WS <span class="hlt">lightning</span> forecasting operations. The equations also performed well in other <span class="hlt">tests</span>. As a result, the new equations will be added to the current set of tools used by the 45 WS to determine the probability of <span class="hlt">lightning</span> for their daily planning forecast. The results from these equations are meant to be used as first-guess guidance when developing the <span class="hlt">lightning</span> probability forecast for the day. They provide an objective base from which forecasters can use other observations, model data, consultation with other forecasters, and their own experience to create the final <span class="hlt">lightning</span> probability for the 1100 UTC briefing.</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> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810028958&hterms=rust&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Drust','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810028958&hterms=rust&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Drust"><span>Thunderstorm Overflight <span class="hlt">Program</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Vaughan, O. H., Jr.; Vonnegut, B.; Orville, R.; Brook, M.; Tennis, R.; Rhodes, C.; Rust, D.</p> <p>1980-01-01</p> <p>The Thunderstorm Overflight <span class="hlt">Program</span> is being conducted by NASA, NOAA, and universities to evaluate the feasibility of making meaningful measurements of <span class="hlt">lightning</span> parameters from an orbiting platform above thunderstorms. A NASA instrumented U-2 high-altitude research aircraft was used during the summer of 1979 and spring of 1980 to collect data over the tops of the thunderstorms while ground-based measurements were being made simultaneously. <span class="hlt">Test</span> sites at Langmuir Laboratory, Socorro, N. Mex., and the National Severe Storms Laboratory, Norman, Okla. were used for this <span class="hlt">program</span>. Additional flights are planned for the spring and summer of 1981. Data from the NASA U-2 flights will also be used to interpret measurements made during the Nighttime/Daytime Optical Survey <span class="hlt">Lightning</span> Experiment to be flown on the Space Shuttle in late 1981.</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('http://hdl.handle.net/2060/20150010964','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150010964"><span>A Fiber-Optic Current Sensor for <span class="hlt">Lightning</span> Measurement Applications</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.</p> <p>2015-01-01</p> <p>An optical-fiber sensor based on Faraday Effect is developed for measuring total <span class="hlt">lightning</span> electric current. It has many unique capabilities not possible with traditional current sensors. Designed for aircraft installation, the sensor is lightweight, non-conducting, structure-conforming, and is immune to electromagnetic interference, hysteresis and saturation. It can also be used on windmills, <span class="hlt">lightning</span> towers, and can help validate <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. The broadband, dual-detector, reflective polarimetric scheme allows measurement of both DC component and AC waveforms with about 60 dB dynamic range. Three sensor systems were built with different sensitivities from different laser wavelengths. Operating at 850nm, the first system uses twisted single-mode fiber and has a 150 A - 150 KA range. The second system operates at 1550nm, uses spun polarization maintaining fiber, and can measure 400 A - 400 KA. Both systems were validated with rocket-triggered <span class="hlt">lightning</span> measurements and achieved excellent results when compared to a resistive shunt. The third system operates at 1310nm, uses spun polarization maintaining fiber, and can measure approximately 300 A - 300 KA. High current measurements up to 200 KA were demonstrated at a commercial <span class="hlt">lightning</span> <span class="hlt">test</span> facility. The system was recently installed on an aircraft and flown near icing weather conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9480E..0XN','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9480E..0XN"><span>A fiber-optic current sensor for <span class="hlt">lightning</span> measurement applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.</p> <p>2015-05-01</p> <p>An optical-fiber sensor based on Faraday Effect is developed for measuring total <span class="hlt">lightning</span> electric current. It has many unique capabilities not possible with traditional current sensors. Designed for aircraft installation, the sensor is lightweight, non-conducting, structure-conforming, and is immune to electromagnetic interference, hysteresis and saturation. It can also be used on windmills, <span class="hlt">lightning</span> towers, and can help validate <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. The broadband, dual-detector, reflective polarimetric scheme allows measurement of both DC component and AC waveforms with about 60 dB dynamic range. Three sensor systems were built with different sensitivities from different laser wavelengths. Operating at 850nm, the first system uses twisted single-mode fiber and has a 150 A - 150 KA range. The second system operates at 1550nm, uses spun polarization maintaining fiber, and can measure 400 A - 400 KA. Both systems were validated with rocket-triggered <span class="hlt">lightning</span> measurements and achieved excellent results when compared to a resistive shunt. The third system operates at 1310nm, uses spun polarization maintaining fiber, and can measure approximately 300 A - 300 KA. High current measurements up to 200 KA were demonstrated at a commercial <span class="hlt">lightning</span> <span class="hlt">test</span> facility. The system was recently installed on an aircraft and flown near icing weather conditions.</p> </li> <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('https://ntrs.nasa.gov/search.jsp?R=19880047743&hterms=radiation+electromagnetic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dradiation%2Belectromagnetic','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880047743&hterms=radiation+electromagnetic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dradiation%2Belectromagnetic"><span>An experimental <span class="hlt">test</span> of the 'transmission-line model' of electromagnetic radiation from triggered <span class="hlt">lightning</span> return strokes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Willett, J. C.; Idone, V. P.; Orville, R. E.; Leteinturier, C.; Eybert-Berard, A.</p> <p>1988-01-01</p> <p>Peak currents, two-dimensional average propagation speeds, and electric field waveforms for a number of subsequent return strikes in rocket-triggered <span class="hlt">lightning</span> flashes were measured in order to <span class="hlt">test</span> the 'transmission-line model' of return-stroke radiation of Uman and McLain (1970). Reasonable agreement is found between the propagation speeds measured with the streak camera and those deduced from the transmission-line model. A modification of the model is proposed in which two wave fronts travel upward and downward away from a junction point a short distance above the ground.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988JGR....93.3867W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988JGR....93.3867W"><span>An experimental <span class="hlt">test</span> of the 'transmission-line model' of electromagnetic radiation from triggered <span class="hlt">lightning</span> return strokes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Willett, J. C.; Idone, V. P.; Orville, R. E.; Leteinturier, C.; Eybert-Berard, A.</p> <p>1988-04-01</p> <p>Peak currents, two-dimensional average propagation speeds, and electric field waveforms for a number of subsequent return strikes in rocket-triggered <span class="hlt">lightning</span> flashes were measured in order to <span class="hlt">test</span> the 'transmission-line model' of return-stroke radiation of Uman and McLain (1970). Reasonable agreement is found between the propagation speeds measured with the streak camera and those deduced from the transmission-line model. A modification of the model is proposed in which two wave fronts travel upward and downward away from a junction point a short distance above the ground.</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('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://hdl.handle.net/2060/19890006114','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890006114"><span>Application of triggered <span class="hlt">lightning</span> numerical models to the F106B and extension to other aircraft</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ng, Poh H.; Dalke, Roger A.; Horembala, Jim; Rudolph, Terence; Perala, Rodney A.</p> <p>1988-01-01</p> <p>The goal of the F106B Thunderstorm Research <span class="hlt">Program</span> is to characterize the <span class="hlt">lightning</span> environment for aircraft in flight. This report describes the application of numerical electromagnetic models to this problem. Topics include: (1) Extensive application of linear triggered <span class="hlt">lightning</span> to F106B data; (2) Electrostatic analysis of F106B field mill data; (3) Application of subgrid modeling to F106B nose region, including both static and nonlinear models; (4) Extension of F106B results to other aircraft of varying sizes and shapes; and (5) Application of nonlinear model to interaction of F106B with <span class="hlt">lightning</span> leader-return stroke event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120001412','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120001412"><span><span class="hlt">Lightning</span> NOx Production and Its Consequences for Tropospheric Chemistry</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pickering, Kenneth E.</p> <p>2005-01-01</p> <p>Cloud-resolving case-study simulations of convective transport and <span class="hlt">lightning</span> NO production have yielded results which are directly applicable to the design of <span class="hlt">lightning</span> parameterizations for global chemical transport models. In this work we have used cloud-resolving models (the Goddard Cumulus Ensemble Model (GCE) and MMS) to drive an off-line cloud-scale chemical transport model (CSCTM). The CSCTM, in conjunction with aircraft measurements of NO x in thunderstorms and ground-l;>ased <span class="hlt">lightning</span> observations, has been used to constrain the amount of NO produced per flash. Cloud and chemistry simulations for several case studies of storms in different environments will be presented. Observed <span class="hlt">lightning</span> flash rates have been incorporated into the CSCTM, and several scenarios of NO production per intracloud (IC) and per cloud-to-ground (CG) flash have been <span class="hlt">tested</span> for each storm. The resulting NOx mixing ratios are compared with aircraft measurements taken within the storm (typically the anvil region) to determine the most likely NO production scenario. The range of values of NO production per flash (or per meter of <span class="hlt">lightning</span> channel length) that have been deduced from the model will be shown and compared with values of production in the literature that have been deduced from observed NO spikes and from anvil flux calculations. Results show that on a per flash basis, IC flashes are nearly as productive of NO as CG flashes. This result simplifies the <span class="hlt">lightning</span> parameterization for global models (ie., an algorithm for estimating the IC/CG ratio is not necessary). Vertical profiles of <span class="hlt">lightning</span> NOx mass at the end of the 3-D storm simulations have been summarized to yield suggested profiles for use in global models. Estimates of mean NO production per flash vary by a factor of three from one simulated storm to another. When combined with the global flash rate of 44 flashes per second from NASA's Optical Transient Detector (OTD) measurements, these estimates and the results</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://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('http://hdl.handle.net/2060/20140006918','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140006918"><span>Integration of the Total <span class="hlt">Lightning</span> Jump Algorithm into Current Operational Warning Environment Conceptual Models</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shultz, Christopher J.; Carey, Lawrence D.; Schultz, Elise V.; Stano, Geoffrey T.; Blakeslee, Richard J.; Goodman, Steven J.</p> <p>2014-01-01</p> <p>The presence and rates of total <span class="hlt">lightning</span> are both correlated to and physically dependent upon storm updraft strength, mixed phase precipitation volume and the size of the charging zone. The updraft modulates the ingredients necessary for electrification within a thunderstorm, while the updraft also plays a critical role in the development of severe and hazardous weather. Therefore utilizing this relationship, the monitoring of <span class="hlt">lightning</span> rates and jumps provides an additional piece of information on the evolution of a thunderstorm, more often than not, at higher temporal resolution than current operational radar systems. This correlation is the basis for the total <span class="hlt">lightning</span> jump algorithm that has been developed in recent years. Currently, the <span class="hlt">lightning</span> jump algorithm is being <span class="hlt">tested</span> in two separate but important efforts. Schultz et al. (2014; AMS 10th Satellite Symposium) is exploring the transition of the algorithm from its research based formulation to a fully objective algorithm that includes storm tracking, Geostationary <span class="hlt">Lightning</span> Mapper (GLM) Proxy data and the <span class="hlt">lightning</span> jump algorithm. Chronis et al. (2014; this conference) provides context for the transition to current operational forecasting using <span class="hlt">lightning</span> mapping array based products. However, what remains is an end to end physical and dynamical basis for relating <span class="hlt">lightning</span> rates to severe storm manifestation, so the forecaster has a reason beyond simple correlation to utilize the <span class="hlt">lightning</span> jump algorithm within their severe storm conceptual models. Therefore, the physical basis for the <span class="hlt">lightning</span> jump algorithm in relation to severe storm dynamics and microphysics is a key component that must be further explored. Many radar studies have examined flash rates and their relation to updraft strength, updraft volume, precipitation-sized ice mass, etc.; however, relation specifically to <span class="hlt">lightning</span> jumps is fragmented within the literature. Thus the goal of this study is to use multiple Doppler techniques to</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('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('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('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('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> </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/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=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> <span class="hlt">tests</span> 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 laboratory 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, laboratory <span class="hlt">tests</span> 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> <span class="hlt">tests</span> 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 laboratory 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, laboratory <span class="hlt">tests</span> 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=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://adsabs.harvard.edu/abs/2016JGRD..12112298S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRD..12112298S"><span>WWLLN <span class="hlt">lightning</span> and satellite microwave radiometrics at 37 to 183 GHz: Thunderstorms in the broad tropics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Solorzano, N. N.; Thomas, J. N.; Hutchins, M. L.; Holzworth, R. H.</p> <p>2016-10-01</p> <p>We investigate <span class="hlt">lightning</span> strokes and deep convection through the examination of cloud-to-ground (CG) <span class="hlt">lightning</span> from the World Wide <span class="hlt">Lightning</span> Location Network (WWLLN) and passive microwave radiometer data. Microwave channels at 37 to 183.3 GHz are provided by the Tropical Rainfall Measuring Mission satellite (TRMM) Microwave Imager (TMI) and the Special Sensor Microwave Imager/Sounder (SSMIS) on the Defense Meteorological Satellite <span class="hlt">Program</span> (DMSP) satellite F16. The present study compares WWLLN stroke rates and minimum radiometer brightness temperatures (Tbs) for two Northern Hemisphere and Southern Hemisphere summers (2009-2011) in the broad tropics (35°S to 35°N). To identify deep convection, we use <span class="hlt">lightning</span> data and Tbs derived from all channels and differences in the Tbs (ΔTbs) of the three water vapor channels near 183.3 GHz. We find that stroke probabilities increase with increasing Tb depressions for all frequencies examined. Moreover, we apply methods that use the 183.3 GHz channels to pinpoint deep convection associated with <span class="hlt">lightning</span>. High <span class="hlt">lightning</span> stroke probabilities are found over land regions for both intense and relatively weak convective systems, although the TMI 85 GHz results should be used with caution as they are affected by a 7 km gap between the conical scans. Over the ocean, <span class="hlt">lightning</span> is associated mostly with larger Tb depressions. Generally, our results support the noninductive thundercloud charging mechanism but do not rule out the inductive mechanism during the mature stages of storms. Lastly, we present a case study in which <span class="hlt">lightning</span> stroke rates are used to reconstruct microwave radiometer Tbs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993JGR....9822887F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993JGR....9822887F"><span>Parameters of triggered-<span class="hlt">lightning</span> flashes in Florida and Alabama</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fisher, R. J.; Schnetzer, G. H.; Thottappillil, R.; Rakov, V. A.; Uman, M. A.; Goldberg, J. D.</p> <p>1993-12-01</p> <p>Channel base currents from triggered <span class="hlt">lightning</span> were measured at the NASA Kennedy Space Center, Florida, during summer 1990 and at Fort McClellan, Alabama, during summer 1991. Additionally, 16-mm cinematic records with 3- or 5-ms resolution were obtained for all flashes, and streak camera records were obtained for three of the Florida flashes. The 17 flashes analyzed here contained 69 strokes, all lowering negative charge from cloud to ground. Statistics on interstroke interval, no-current interstroke interval, total stroke duration, total stroke charge, total stroke action integral (∫ i2dt), return stroke current wave front characteristics, time to half peak value, and return stroke peak current are presented. Return stroke current pulses, characterized by rise times of the order of a few microseconds or less and peak values in the range of 4 to 38 kA, were found not to occur until after any preceding current at the bottom of the <span class="hlt">lightning</span> channel fell below the noise level of less than 2 A. Current pulses associated with M components, characterized by slower rise times (typically tens to hundreds of microseconds) and peak values generally smaller than those of the return stroke pulses, occurred during established channel current flow of some tens to some hundreds of amperes. A relatively strong positive correlation was found between return stroke current average rate of rise and current peak. There was essentially no correlation between return stroke current peak and 10-90% rise time or between return stroke peak and the width of the current waveform at half of its peak value. Parameters of the <span class="hlt">lightning</span> flashes triggered in Florida and Alabama are similar to each other but are different from those of triggered <span class="hlt">lightning</span> recorded in New Mexico during the 1981 Thunderstorm Research International <span class="hlt">Program</span>. Continuing currents that follow return stroke current peaks and last for more than 10 ms exhibit a variety of wave shapes that we have subdivided into four</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023380','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023380"><span><span class="hlt">Lightning</span> induced currents in aircraft wiring using low level injection techniques</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stevens, E. G.; Jordan, D. T.</p> <p>1991-01-01</p> <p>Various techniques were studied to predict the transient current induced into aircraft wiring bundles as a result of an aircraft <span class="hlt">lightning</span> strike. A series of aircraft measurements were carried out together with a theoretical analysis using computer modeling. These <span class="hlt">tests</span> were applied to various aircraft and also to specially constructed cylinders installed within coaxial return conductor systems. Low level swept frequency CW (carrier waves), low level transient and high level transient injection <span class="hlt">tests</span> were applied to the aircraft and cylinders. Measurements were made to determine the transfer function between the aircraft drive current and the resulting skin currents and currents induced on the internal wiring. The full threat <span class="hlt">lightning</span> induced transient currents were extrapolated from the low level data using Fourier transform techniques. The aircraft and cylinders used were constructed from both metallic and CFC (carbon fiber composite) materials. The results show the pulse stretching phenomenon which occurs for CFC materials due to the diffusion of the <span class="hlt">lightning</span> current through carbon fiber materials. Transmission Line Matrix modeling techniques were used to compare theoretical and measured currents.</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://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 Laboratory, 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/2060/19810016745','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/2060/20110015811','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://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('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 Laboratory 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://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('https://images.nasa.gov/#/details-KSC-07PD-3005.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-KSC-07PD-3005.html"><span>Large Crawler Crane for new <span class="hlt">lightning</span> protection system</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2007-10-25</p> <p>A large crawler crane traveling long one of the crawlerway tracks makes the turn toward Launch Pad 39B. The crane with its 70-foot boom will be used to construct a new <span class="hlt">lightning</span> protection system for the Constellation <span class="hlt">Program</span> and Ares/Orion launches. Pad B will be the site of the first Ares vehicle launch, including Ares I-X which is scheduled for April 2009.</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://images.nasa.gov/#/details-KSC-07PD-3004.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-KSC-07PD-3004.html"><span>Large Crawler Crane for new <span class="hlt">lightning</span> protection system</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2007-10-25</p> <p>A large crawler crane travels along one of the crawlerway tracks on its way to Launch Pad 39B. The crane with its 70-foot boom will be used to construct a new <span class="hlt">lightning</span> protection system for the Constellation <span class="hlt">Program</span> and Ares/Orion launches. Pad B will be the site of the first Ares vehicle launch, including Ares I-X which is scheduled for April 2009.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-KSC-07PD-3003.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-KSC-07PD-3003.html"><span>Large Crawler Crane for new <span class="hlt">lightning</span> protection system</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2007-10-25</p> <p>A large crawler crane moves past the Vehicle Assembly Building on its way to Launch Pad 39B. The crane with its 70-foot boom will be used to construct a new <span class="hlt">lightning</span> protection system for the Constellation <span class="hlt">Program</span> and Ares/Orion launches. Pad B will be the site of the first Ares vehicle launch, including Ares I-X which is scheduled for April 2009.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5693383','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5693383"><span>Kinematic and Microphysical Significance of <span class="hlt">Lightning</span> Jumps versus Non-Jump Increases in Total Flash Rate</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, Christopher J.; Carey, Lawrence D.; Schultz, Elise V.; Blakeslee, Richard J.</p> <p>2017-01-01</p> <p>Thirty-nine thunderstorms are examined using multiple-Doppler, polarimetric and total <span class="hlt">lightning</span> observations to understand the role of mixed phase kinematics and microphysics in the development of <span class="hlt">lightning</span> jumps. This sample size is larger than those of previous studies on this topic. The principal result of this study is that <span class="hlt">lightning</span> jumps are a result of mixed phase updraft intensification. Larger increases in intense updraft volume (≥ 10 m s−1) and larger changes in peak updraft speed are observed prior to <span class="hlt">lightning</span> jump occurrence when compared to other non-jump increases in total flash rate. Wilcoxon-Mann-Whitney Rank Sum <span class="hlt">testing</span> yields p-values ≤0.05, indicating statistical independence between <span class="hlt">lightning</span> jump and non-jump distributions for these two parameters. Similar changes in mixed phase graupel mass magnitude are observed prior to <span class="hlt">lightning</span> jumps and non-jump increases in total flash rate. The p-value for graupel mass change is p=0.096, so jump and non-jump distributions for graupel mass change are not found statistically independent using the p=0.05 significance level. Timing of updraft volume, speed and graupel mass increases are found to be 4 to 13 minutes in advance of <span class="hlt">lightning</span> jump occurrence. Also, severe storms without <span class="hlt">lightning</span> jumps lack robust mixed phase updrafts, demonstrating that mixed phase updrafts are not always a requirement for severe weather occurrence. Therefore, the results of this study show that <span class="hlt">lightning</span> jump occurrences are coincident with larger increases in intense mixed phase updraft volume and peak updraft speed than smaller non-jump increases in total flash rate. PMID:29158622</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29158622','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29158622"><span>Kinematic and Microphysical Significance of <span class="hlt">Lightning</span> Jumps versus Non-Jump Increases in Total Flash Rate.</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; Carey, Lawrence D; Schultz, Elise V; Blakeslee, Richard J</p> <p>2017-02-01</p> <p>Thirty-nine thunderstorms are examined using multiple-Doppler, polarimetric and total <span class="hlt">lightning</span> observations to understand the role of mixed phase kinematics and microphysics in the development of <span class="hlt">lightning</span> jumps. This sample size is larger than those of previous studies on this topic. The principal result of this study is that <span class="hlt">lightning</span> jumps are a result of mixed phase updraft intensification. Larger increases in intense updraft volume (≥ 10 m s -1 ) and larger changes in peak updraft speed are observed prior to <span class="hlt">lightning</span> jump occurrence when compared to other non-jump increases in total flash rate. Wilcoxon-Mann-Whitney Rank Sum <span class="hlt">testing</span> yields p-values ≤0.05, indicating statistical independence between <span class="hlt">lightning</span> jump and non-jump distributions for these two parameters. Similar changes in mixed phase graupel mass magnitude are observed prior to <span class="hlt">lightning</span> jumps and non-jump increases in total flash rate. The p-value for graupel mass change is p=0.096, so jump and non-jump distributions for graupel mass change are not found statistically independent using the p=0.05 significance level. Timing of updraft volume, speed and graupel mass increases are found to be 4 to 13 minutes in advance of <span class="hlt">lightning</span> jump occurrence. Also, severe storms without <span class="hlt">lightning</span> jumps lack robust mixed phase updrafts, demonstrating that mixed phase updrafts are not always a requirement for severe weather occurrence. Therefore, the results of this study show that <span class="hlt">lightning</span> jump occurrences are coincident with larger increases in intense mixed phase updraft volume and peak updraft speed than smaller non-jump increases in total flash rate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160014899','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160014899"><span>Kinematic and Microphysical Significance of <span class="hlt">Lightning</span> Jumps Versus Non-Jump Increases in Total Flash Rate</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.; Carey, Lawrence D.; Schultz, Elise V.; Blakeslee, Richard J.</p> <p>2017-01-01</p> <p>Thirty-nine thunderstorms are examined using multiple-Doppler, polarimetric and total <span class="hlt">lightning</span> observations to understand the role of mixed phase kinematics and microphysics in the development of <span class="hlt">lightning</span> jumps. This sample size is larger than those of previous studies on this topic. The principal result of this study is that <span class="hlt">lightning</span> jumps are a result of mixed phase updraft intensification. Larger increases in intense updraft volume greater than or equal to 10 m(sup -1) and larger changes in peak updraft speed are observed prior to <span class="hlt">lightning</span> jump occurrence when compared to other non-jump increases in total ash rate. Wilcoxon-Mann-Whitney Rank Sum <span class="hlt">testing</span> yields p-values 0.05, indicating statistical independence between <span class="hlt">lightning</span> jump and non-jump distributions for these two parameters. Similar changes in mixed phase graupel mass magnitude are observed prior to <span class="hlt">lightning</span> jumps and non-jump increases in total ash rate. The p-value for graupel mass change is p=0.096, so jump and non-jump distributions for graupel mass change are not found statistically independent using the p=0.05 significance level. Timing of updraft volume, speed and graupel mass increases are found to be 4 to 13 minutes in advance of <span class="hlt">lightning</span> jump occurrence. Also, severe storms without <span class="hlt">lightning</span> jumps lack robust mixed phase updrafts, demonstrating that mixed phase updrafts are not always a requirement for severe weather occurrence. Therefore, the results of this study show that <span class="hlt">lightning</span> jump occurrences are coincident with larger increases in intense mixed phase updraft volume and peak updraft speed than smaller non-jump increases in total ash rate.</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> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20090032643&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=20090032643&hterms=bateman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbateman"><span>Developing <span class="hlt">Lightning</span> Prediction Tools for the CCAFS Dual-Polarimetric Radar</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Petersen, W. A.; Carey, L. D.; Deierling, W.; Johnson, E.; Bateman, M.</p> <p>2009-01-01</p> <p> ensuing <span class="hlt">lightning</span> in the sub-tropical/tropical convection typical of the southeastern U.S., Maritime Continent, and southwestern Amazon. The polarimetric signatures detected in this setting provide a basis for automated 3-D detection of hydrometeor types in fuzzy logic hydrometeor identification algorithms (HID). Our working hypothesis is that improvement in <span class="hlt">lightning</span> onset warning lead time and specificity for a given storm, relative to application of a Z-threshold algorithm, should arise as a consequence of the ability of dual-polarimetric radar to unambiguously detect and identify (through HID algorithms) the updraft elevation of rain-water cores above the freezing level and subsequent onset of drop freezing, riming, and robust mixed phase processes leading to significant charge separation and <span class="hlt">lightning</span>. This type of algorithm, though dependent on the quality of the polarimetric data should be less susceptible to variable Z-calibration that can impact a given Z-threshold approach. To facilitate development of the algorithm while the 45WS dual-pol radar is in its current <span class="hlt">test</span> stages and to evaluate the impact of polarimetric data quality (e.g., modified scan parameters and sampling) on the ensuing algorithms, we are using the ARMOR C-band dual-pol radar in Huntsville combined with N. Alabama LMA data and ARMOR HID algorithms [NCAR algorithm modified for application at C-band] in a testbed fashion. For <span class="hlt">lightning</span> cessation we are revisiting the application of differential propagation phase variables for the monitoring of ice crystal alignment driven by in-cloud electric fields combined with metrics of ice water path (i.e., vertically integrated reflectivity). Importantly it should be noted that this approach is still very much a research topic and as such, we will explore operational applications that involve radar frequencies other than C-Band by using the UAH MAX X-band dual-pol radar in slow staring modes.</p> </li> <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/17777757','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17777757"><span>Daylight time-resolved photographs 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>Qrville, R E; Lala, G G; Idone, V P</p> <p>1978-07-07</p> <p><span class="hlt">Lightning</span> dart leaders and return strokes have been recorded in daylight with both good spatial resolution and good time resolution as part of the Thunder-storm Research International <span class="hlt">Program</span>. The resulting time-resolved photographs are apparently equivalent to the best data obtained earlier only at night. Average two-dimensional return stroke velocities in four subsequent strokes between the ground and a height of 1400 meters were approximately 1.3 x 10(8) meters per second. The estimated systematic error is 10 to 15 percent.</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://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.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://hdl.handle.net/2060/20110024190','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110024190"><span>Forecasting <span class="hlt">Lightning</span> at Kennedy Space Center/Cape Canaveral Air Force Station, Florida</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 equation development. Fifteen years (1 989-2003) of warm season data were used to develop the forecast equations. The data sources included a local network of cloud-to-ground <span class="hlt">lightning</span> sensors called the Cloud-to-Ground <span class="hlt">Lightning</span> Surveillance System (CGLSS), 1200 UTC Florida synoptic soundings, and the 1000 UTC CCAFS sounding. Data from CGLSS were used to determine <span class="hlt">lightning</span> occurrence for each day. The 1200 UTC soundings were used to calculate the synoptic-scale flow regimes and the 1000 UTC soundings were used to calculate local stability parameters, which were used as candidate predictors of <span class="hlt">lightning</span> occurrence. Five logistic regression forecast equations were created through careful selection and elimination of the candidate predictors. The resulting equations contain five to six predictors each. Results from four performance <span class="hlt">tests</span> indicated that the equations showed an increase in skill over several standard forecasting methods, good reliability, an ability to distinguish between non-<span class="hlt">lightning</span> and <span class="hlt">lightning</span> days, and good accuracy measures and skill scores. Given the overall good performance the 45 WS requested that the equations be transitioned to operations and added to the current set of tools used to determine the daily <span class="hlt">lightning</span> probability of occurrence.</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('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> </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-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> <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('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 <span class="hlt">tested</span>, which is capable of delivering more than 50 kA to an 8 micro-H <span class="hlt">test</span> object. The simulator was designed to be a versatile device in the <span class="hlt">lightning</span> laboratory 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 <span class="hlt">test</span> 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 <span class="hlt">test</span> results are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19800013448&hterms=Electromagnetic+Pulse&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DElectromagnetic%2BPulse','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19800013448&hterms=Electromagnetic+Pulse&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DElectromagnetic%2BPulse"><span>Broadband electromagnetic sensors for aircraft <span class="hlt">lightning</span> research. [electromagnetic effects of <span class="hlt">lightning</span> on aircraft digital equipment</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.; Zaepfel, K. P.</p> <p>1980-01-01</p> <p>A set of electromagnetic sensors, or electrically-small antennas, is described. The sensors are designed for installation on an F-106 research aircraft for the measurement of electric and magnetic fields and currents during a <span class="hlt">lightning</span> strike. The electric and magnetic field sensors mount on the aircraft skin. The current sensor mounts between the nose boom and the fuselage. The sensors are all on the order of 10 cm in size and should produce up to about 100 V for the estimated <span class="hlt">lightning</span> fields. The basic designs are the same as those developed for nuclear electromagnetic pulse studies. The most important electrical parameters of the sensors are the sensitivity, or equivalent area, and the bandwidth (or rise time). Calibration of sensors with simple geometries is reliably accomplished by a geometric analysis; all the sensors discussed possess geometries for which the sensitivities have been calculated. For the calibration of sensors with more complex geometries and for general <span class="hlt">testing</span> of all sensors, two transmission lines were constructed to transmit known pulsed fields and currents over the sensors.</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://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('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://adsabs.harvard.edu/abs/2012JESS..121..211Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JESS..121..211Y"><span>Audible thunder characteristic and the relation between peak frequency and <span class="hlt">lightning</span> parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yuhua, Ouyang; Ping, Yuan</p> <p>2012-02-01</p> <p>In recent summers, some natural <span class="hlt">lightning</span> optical spectra and audible thunder signals were observed. Twelve events on 15 August 2008 are selected as samples since some synchronizing information about them are obtained, such as <span class="hlt">lightning</span> optical spectra, surface E-field changes, etc. By using digital filter and Fourier transform, thunder frequency spectra in observation location have been calculated. Then the two main propagation effects, finite amplitude propagation and attenuation by air, are calculated. Upon that we take the <span class="hlt">test</span> thunder frequency spectra and work backward to recalculate the original frequency spectra near generation location. Thunder frequency spectra and the frequency distribution varying with distance are researched. According to the theories on plasma, the channel temperature and electron density are further calculated by transition parameters of lines in <span class="hlt">lightning</span> optical spectra. Pressure and the average ionization degree of each discharge channel are obtained by using Saha equations, charge conservation equations and particle conservation equations. Moreover, the relationship between the peak frequency of each thunder and channel parameters of the <span class="hlt">lightning</span> is studied.</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=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> </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('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://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 Laboratory, Pasadena, CA manages the Galileo mission for</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('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.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 Laboratory in Albuquerque calculated the EM fields inside a Faraday</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/2060/20130012532','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130012532"><span>NASA Standard Initiator Susceptibility to UHF and S-Band Radio Frequency Power and <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>Burnham, Karen; Scully, Robert; Norgard, John</p> <p>2013-01-01</p> <p>The NASA Standard Initiator (NSI) is an important piece of pyrotechnic equipment used in many space applications. This presentation will outline the results of a series of <span class="hlt">tests</span> done at UHF and S-Band frequencies to determine NSI susceptibility to Radio Frequency (RF) power. The results show significant susceptibility to pulsed RF power in the S-Band region. Additional <span class="hlt">testing</span> with <span class="hlt">lightning</span> pulses injected into the firing line harness, modelling the indirect effects of a <span class="hlt">lightning</span> strike to a spacecraft, showed no vulnerability</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130009741','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130009741"><span>NASA Standard Initiator Susceptibility to UHF and S-Band Radio Frequency Power and <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>Burnham, Karen; Scully, Robert C.; Norgard, John D.</p> <p>2013-01-01</p> <p>The NASA Standard Initiator (NSI) is an important piece of pyrotechnic equipment used in many space applications. This paper outlines the results of a series of <span class="hlt">tests</span> done at UHF and S-Band frequencies to determine NSI susceptibility to Radio Frequency (RF) power. The results show significant susceptibility to pulsed RF power in the S-Band region. Additional <span class="hlt">testing</span> with <span class="hlt">lightning</span> pulses injected into the firing line harness, modelling the indirect effects of a <span class="hlt">lightning</span> strike to a spacecraft, showed no vulnerability.</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/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> <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> </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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