Science.gov

Sample records for physical weathering processes

  1. Weather Information Processing

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Science Communications International (SCI), formerly General Science Corporation, has developed several commercial products based upon experience acquired as a NASA Contractor. Among them are METPRO, a meteorological data acquisition and processing system, which has been widely used, RISKPRO, an environmental assessment system, and MAPPRO, a geographic information system. METPRO software is used to collect weather data from satellites, ground-based observation systems and radio weather broadcasts to generate weather maps, enabling potential disaster areas to receive advance warning. GSC's initial work for NASA Goddard Space Flight Center resulted in METPAK, a weather satellite data analysis system. METPAK led to the commercial METPRO system. The company also provides data to other government agencies, U.S. embassies and foreign countries.

  2. Space Weathering Processes on Mercury

    NASA Technical Reports Server (NTRS)

    Noble, S. K.; Pieters, C. M.

    2002-01-01

    Like the Moon, Mercury has no atmosphere to protect it from the harsh space environment and therefore it is expected that it will incur the effects of space weathering. These weathering processes are capable of both creating regolith and altering its optical properties. However, there are many important differences between the environments of Mercury and the Moon. These environmental differences will almost certainly affect the weathering processes as well as the products of those processes. It should be possible to observe the effects of these differences in Vis/NIR spectra of the type expected to be returned by MESSENGER. More importantly, understanding these weathering processes and their consequences is essential for evaluating the spectral data returned from MESSENGER and other missions in order to determine the mineralogy and the iron content of the Mercurian surface. Theoretical and experimental work has been undertaken in order to better understand these consequences.

  3. Soil Genesis and Development, Lesson 2 - Processes of Weathering

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weathering processes — which include physical, chemical, and biological — contribute to the development of soil. The learning objectives of the lesson are: 1) Define and distinguish physical, chemical, and biological weathering processes; and 2) Describe how rock and mineral properties and environm...

  4. Physical and chemical weathering. [of Martian surface and rocks

    NASA Technical Reports Server (NTRS)

    Gooding, James L.; Arvidson, Raymond E.; Zolotov, Mikhail IU.

    1992-01-01

    Physical and chemical weathering processes that might be important on Mars are reviewed, and the limited observations, including relevant Viking results and laboratory simulations, are summarized. Physical weathering may have included rock splitting through growth of ice, salt or secondary silicate crystals in voids. Chemical weathering probably involved reactions of minerals with water, oxygen, and carbon dioxide, although predicted products vary sensitively with the abundance and physical form postulated for the water. On the basis of kinetics data for hydration of rock glass on earth, the fate of weathering-rind formation on glass-bearing Martian volcanic rocks is tentatively estimated to have been on the order of 0.1 to 4.5 cm/Gyr; lower rates would be expected for crystalline rocks.

  5. Space Weather: Physics and Effects

    NASA Astrophysics Data System (ADS)

    Hughes, W. Jeffrey

    2009-03-01

    With the launching of Sputnik, Explorer 1, and the other early satellites, the new discipline of space physics was born, about 50 years ago. Although earlier ground-based observations had provided strong hints about the nature of our space environment above the upper atmosphere, those early satellites initiated a series of surprises and discoveries, including Van Allen's discovery of the Earth's radiation belts. Young scientists were attracted to this new field, and it grew quickly. When the Journal of Geophysical Research was divided into two sections, in 1964, one section was devoted to space physics. The field explored not only new regions of space but also a new state of matter: the rarefied, fully ionized plasma that fills space and interacts intimately with magnetic fields.

  6. Space Weather: Physics, Effects and Predictability

    NASA Astrophysics Data System (ADS)

    Singh, A. K.; Siingh, Devendraa; Singh, R. P.

    2010-12-01

    The time varying conditions in the near-Earth space environment that may affect space-borne or ground-based technological systems and may endanger human health or life are referred to as space weather. Space weather effects arise from the dynamic and highly variable conditions in the geospace environment starting from explosive events on the Sun (solar flares), Coronal Mass Ejections near the Sun in the interplanetary medium, and various energetic effects in the magnetosphere-ionosphere-atmosphere system. As the utilization of space has become part of our everyday lives, and as our lives have become increasingly dependent on technological systems vulnerable to the space weather influences, the understanding and prediction of hazards posed by these active solar events have grown in importance. In this paper, we review the processes of the Sun-Earth interactions, the dynamic conditions within the magnetosphere, and the predictability of space weather effects on radio waves, satellites and ground-based technological systems today.

  7. Physical weathering and modification of a rhyolitic hyaloclastite in Iceland

    NASA Astrophysics Data System (ADS)

    de Vet, S. J.; Mittelmeijer-Hazeleger, M. C.; Braakhekke, J. J. M.; Cammeraat, L. H.

    2014-06-01

    Fragmental volcanic glass or `hyaloclastite' is a common glaciovolcanic eruption product that is formed in large abundance during basaltic, andesitic and rhyolitic subglacial eruptions. The physical weathering of rhyolitic hyaloclastites differs notably from basaltic hyaloclastites due to differences in cementation and edifice consolidation. As rhyolitic glasses are also much rarer, comparatively little is known about their physical weathering and fracturing characteristics. In the presented study, we provide a process-oriented analysis of the physical modification of subglacially erupted rhyolitic hyaloclastites from the Blhnkur edifice in Torfajkull (Iceland). Frost weathering experiments were performed to determine how vesicular glass particles fragment to finer particle sizes. The surficial porosity of the glass drives such frost weathering through the process of pore pressurisation and was quantified using high-pressure mercury intrusion. Uniaxial compression experiments were carried out to understand how the glass structure responds to the application of external stress. The observed fracturing in both experimental treatments was found to adhere to fractal statistics, which allowed the compression experiments to be used in conjunction with the frost weathering experiments for inferring the fracturing characteristics of rhyolitic volcanic glasses. Transport processes by wind and gravity were simulated by long-duration abrasion experiments in rock tumblers (through granular avalanching), but these low-energy particle interactions were not found to significantly abrade particles. A notable result from our fragmentation experiments was the production of <10 ?m particles. This size range is considered respirable and illustrates how physical weathering can continuously create potentially harmful ash textures; a process which is often overlooked in health hazard assessments after volcanic eruptions. Fragmentation by post-eruptive weathering can lead to overestimations of the fine ash fraction produced by syneruptive fragmentation and granulometric studies therefore need to be appreciative of the effects of such secondary fracturing processes.

  8. The Chemistry and Physics of Space Weathering

    NASA Astrophysics Data System (ADS)

    Britt, D. T.; Schelling, P. K.; Blair, R.

    2015-11-01

    Local chemistry and the nature of the energy input drive space weathering. Weathering products are not random, but the predictable outcome of reactions that depend on chemical feedstock, mineral kinetics, catalytic components, and energetic inputs.

  9. Salt-Induced Physical Weathering of Stone

    NASA Astrophysics Data System (ADS)

    Schiro, M.; Ruiz-Agudo, E.; Rodriguez-Navarro, C.

    2010-12-01

    Salt weathering is recognized as an important mechanism that contributes to the modeling and shaping of the earths surface, in a range of environments spanning from the Sahara desert to Antarctica. It also contributes to the degradation and loss of cultural heritage, particularly carved stone and historic buildings. Soluble salts have recently been suggested to contribute to the shaping of rock outcrops on Mars and are being identified in other planetary bodies such as the moons of Jupiter (Europa and IO)1. Soluble salts such as sulfates, nitrates, chlorides and carbonates of alkali and alkali earth metals can crystallize within the porous system of rocks and building stones, exerting sufficient pressure against the pore walls to fracture the substrate. This physical damage results in increased porosity, thus providing a higher surface area for salt-enhanced chemical weathering. To better understand how salt-induced physical weathering occurs, we have studied the crystallization of the particularly damaging salt, sodium sulfate2, in a model system (a sintered porous glass of controlled porosity and pore size). For this elusive task of studying sub-surface crystallization in pores, we combined a variety of instruments to identify which phases crystallized during evaporation and calculated the supersaturation and associated crystallization pressure that caused damage. The heat of crystallization was measured using differential scanning calorimetry (DSC), providing the timing of crystallization events and phase transitions3, while the evaporation rate was recorded using thermal gravimetry (TG). These methods enabled calculation of the sodium sulfate concentration in solution at every point during evaporation. Two-dimensional X-ray diffraction (2D-XRD) performs synchrotron-like experiments in a normal lab by using a Molybdenum X-ray source (more than 5 times more penetrative than conventional Copper source). Using this method, we determined that the first phase to form within our porous system was the metastable heptahydrate (NaSO4?7H2O)4, followed by mirabilite (NaSO4?10H2O), and finally thenardite (NaSO4). Combining this sequence with data from TG/DSC, we calculated the supersaturation of the solution with respect to each crystallizing phase as well as the associated crystallization pressure5. In situ environmental scanning electron microscopy (ESEM) complemented 2D-XRD data by giving high magnification images of crystallization and phase transitions during dissolution/precipitation cycles. These results give us a clear understanding of sodium sulfate behavior during evaporative crystallization. Further studies will examine different salts and different substrates. This research will help us to better understand the crystallization of salts and associated weathering in cultural heritage, natural environments and possibly, in other planetary bodies. [1] Rodriguez-Navarro, C. (1998) Geophys. Res. Lett., 25, 3249-3252. [2] Rodriguez-Navarro, C., et al. (2000), Cement Concrete Res., 30, 1527-1534. [3] Espinosa, R., Scherer, G., (2008), Environ. Geol., 56, 605-621. [4] Hamilton, A., Hall, C., (2008), J. Anal. Atom. Spectrom., 23, 840-844. [5] Steiger, M., Asmussen, S., (2008), Geochim. Cosmochim. Acta, 72, 4291-4306.

  10. Landslides as weathering reactors; links between physical erosion and weathering in rapidly eroding mountain belts

    NASA Astrophysics Data System (ADS)

    Emberson, R.; Hovius, N.; Galy, A.

    2014-12-01

    The link between physical erosion and chemical weathering is generally modelled with a surface-blanketing weathering zone, where the supply of fresh minerals is tied to the average rate of denudation. In very fast eroding environments, however, sediment production is dominated by landsliding, which acts in a stochastic fashion across the landscape, contrasting strongly with more uniform denudation models. If physical erosion is a driver of weathering at the highest erosion rates, then an alternative weathering model is required. Here we show that landslides can be effective 'weathering reactors'. Previous work modelling the effect of landslides on chemical weathering (Gabet 2007) considered the fresh bedrock surfaces exposed in landslide scars. However, fracturing during the landslide motion generates fresh surfaces, the total surface area of which exceeds that of the exposed scar by many orders of magnitude. Moreover, landslides introduce concavity into hillslopes, which acts to catch precipitation. This is funnelled into a deposit of highly fragmented rock mass with large reactive surface area and limited hydraulic conductivity (Lo et al. 2007). This allows percolating water reaction time for chemical weathering; any admixture of macerated organic debris could yield organic acid to further accelerate weathering. In the South island of New Zealand, seepage from recent landslide deposits has systematically high solute concentrations, far outstripping concentration in runoff from locations where soils are present. River total dissolved load in the western Southern Alps is highly correlated with the rate of recent (<35yrs) landsliding, suggesting that landslides are the dominant locus of weathering in this rapidly eroding landscape. A tight link between landsliding and weathering implies that localized weathering migrates through the landscape with physical erosion; this contrasts with persistent and ubiquitous weathering associated with soil production. Solute fluxes from fast eroding landscapes therefore likely depend on climatic or tectonic forcing of mass wasting; greater precipitation would drive increased weathering, while earthquakes, in generating landslides (Dadson et al. 2003; Chen & Hawkins 2009), may be important in setting long term solute fluxes.

  11. Physical aspects of the weather generator

    NASA Astrophysics Data System (ADS)

    Hantel, Michael; Acs, Ferenc

    1998-12-01

    One task in B AHC is to develop a physical understanding of the weather generator (WG). The core of the WG concept is scale interaction, represented by upscaling and downscaling, between the gridscale atmospheric fields and the subgrid-scale hydrological and ecosystem patterns. This paper considers scale interaction in terms of the convective (=latent plus sensible heat) and rain fluxes. Earth's surface and atmosphere are coupled through these fluxes. However, horizontal scale interaction in the free atmosphere is physically different from that at the surface. Upscaling atmospheric fluxes generates new sub-gridscale fluxes at the lower grid resolution, caused by the gridscale fluxes resolved at the higher grid resolution. Downscaling has to recover these secondary circulations, usually through mesoscale submodels. The same gridscale eddy effect is zero for surface fluxes because there is no cross-surface mass flux of air. The atmospheric fluxes on the various scales are quantified here with an atmospheric diagnostic model (D IAMOD) coupled to a surface flux model (S URFMOD). Two convectively active periods over Europe (one disturbed, one undisturbed) are considered. Upscaling from 100 to 1000 km horizontal resolution generates additional grid-scale eddy fluxes. However, these amount, in both cases, to just 10% of the diagnosed fluxes that are sub-gridscale at 100 km; this suggests that the additional gridscale eddy effect may be negligible in convective situations. We further apply a simple downscaling recipe for disturbed periods (scale the rain flux profiles with the observed surface rain) and for undisturbed periods (scale the convective flux profiles with the observed surface latent plus sensible heat flux). At the Earth's surface, we study the upscaling-downscaling mechanism, not with diagnosed, but with modeled latent and sensible heat fluxes. With a simplified version of S URFMOD, plus the probability density function of soil moisture, we reproduce the fatal impact of taking mean soil moisture for calculating mean evaporation: evaporation can be underestimated by 25% in dry situations and overestimated by 10% in moist situations. We demonstrate how to completely remove this bias. The technique presented here can be generalized to a wide class of deterministic and statistical models and offers a rational framework for the aggregation problem and the WG problem in general.

  12. Detecting Anthropogenic Disturbance on Weathering and Erosion Processes

    NASA Astrophysics Data System (ADS)

    Vanacker, V.; Schoonejans, J.; Bellin, N.; Ameijeiras-Mario, Y.; Opfergelt, S.; Christl, M.

    2014-12-01

    Anthropogenic disturbance of natural vegetation can profoundly alter the physical, chemical and biological processes within soils. Rapid removal of topsoil during intense farming can result in an imbalance between soil production through chemical weathering and physical erosion, with direct implications on local biogeochemical cycling. However, the feedback mechanisms between soil erosion, chemical weathering and biogeochemical cycling in response to anthropogenic forcing are not yet fully understood. In this paper, we analyze dynamic soil properties for a rapidly changing anthropogenic landscape in the Spanish Betic Cordillera; and focus on the coupling between physical erosion, soil production and soil chemical weathering. Modern erosion rates were quantified through analysis of sediment deposition volumes behind check dams, and represent catchment-average erosion rates over the last 10 to 50 years. Soil production rates are derived from in-situ produced 10Be nuclide concentrations, and represent long-term flux rates. In each catchment, soil chemical weathering intensities were calculated for two soil-regolith profiles. Although Southeast Spain is commonly reported as the European region that is most affected by land degradation, modern erosion rates are low (140 t ha-1 yr-1). About 50 % of the catchments are losing soils at a rate of less than 60 t km-2 yr-1. Our data show that modern erosion rates are roughly of the same magnitude as the long-term or cosmogenically-derived erosion rates in the Betic Cordillera. Soils developed on weathered metamorphic rocks have no well-developed profile characteristics, and are generally thin and stony. Nevertheless, soil chemical weathering intensities are high; and question the occurrence of past soil truncation.

  13. Olivine Weathering: Abiotic Versus Biotic Processes as Possible Biosignatures

    NASA Technical Reports Server (NTRS)

    Longazo, T. G.; Wentworth, S. J.; McKay, D. S.; Southam, G.; Clemett, S. J.

    2001-01-01

    A preliminary study to determine how abiotic versus biotic processes affect the weathering of olivine crystals. Perhaps the differences between these weathering processes could be used as biosignatures. Additional information is contained in the original extended abstract.

  14. Understanding Space Weather and the Physics Behind It

    NASA Astrophysics Data System (ADS)

    Knipp, D. J.; Gross, N. A.

    2011-12-01

    A new textbook on space weather, Understanding Space Weather and the Physics Behind It, aimed at upper-level undergraduates and beginning graduate students, contains numerous examples of basic physics applications in space weather. We will highlight a few of the examples from the text. In addition, new material is being developed to support the many references to NOAA Space Weather Prediction Center (SWPC) graphics and scales. Our intent is to provide background and improved understanding of the underpinnings of the operational images. In this presentation we provide a set of questions, tools, and exercises that guide inquiry into the observations and proxies behind some of elements on SWPC's home page. Our materials include observation sequences for the types of space weather disturbances discussed in SWPC's Report of Solar and Geophysical Activity and the NOAA Space Weather Scales. Our instructional materials are in standard electronic document formats and in "dashboard" format supported by tools from the Integrated Space Weather Analysis platform at NASA's Community Coordinated Modeling Center.

  15. Multilayer Scintillation Detector for Nuclear Physics Monitoring of Space Weather

    NASA Astrophysics Data System (ADS)

    Batischev, A. G.; Aleksandrin, S. Yu.; Gurov, Yu. B.; Koldashov, S. V.; Lapushkin, S. V.; Mayorov, A. G.

    The physical characteristics of the multilayer scintillation spectrometer (MSS) for identification and energy measurement of cosmic electrons, positrons and nuclei are considered in this paper. This spectrometer is made on the basis of several plastic scintillator plates with various thick viewed by photomultipliers. Two upper layers are strips of orthogonal scintillators. The nuclei energy measurement range is 3 - 100 MeV/nucleon. Spectrometer is planning for space weather monitoring and investigation of solar-magnetospheric and geophysics effects on satellite. MSS time resolution is about 1 microsecond and it can measure the time profiles of fast processes in the Earth's magnetosphere. Spectrometer experimental characteristics were estimated by means of computer simulation. The ionization loss fluctuations, ion charge exchange during pass through detector and, especially, scintillation quenching effect (Bircs effect) were taken into account in calculations.

  16. Weather.

    ERIC Educational Resources Information Center

    Ruth, Amy, Ed.

    1996-01-01

    This theme issue of "The Goldfinch" focuses on weather in Iowa and weather lore. The bulletin contains historical articles, fiction, activities, and maps. The table of contents lists: (1) "Wild Rosie's Map"; (2) "History Mystery"; (3) "Iowa's Weather History"; (4) "Weather Wonders"; (6) "Seasonal Jobs"; (7) "Fiction: Winter Courage"; (8) "Stayin'…

  17. Sensitivity of mineral dissolution rates to physical weathering : A modeling approach

    NASA Astrophysics Data System (ADS)

    Opolot, Emmanuel; Finke, Peter

    2015-04-01

    There is continued interest on accurate estimation of natural weathering rates owing to their importance in soil formation, nutrient cycling, estimation of acidification in soils, rivers and lakes, and in understanding the role of silicate weathering in carbon sequestration. At the same time a challenge does exist to reconcile discrepancies between laboratory-determined weathering rates and natural weathering rates. Studies have consistently reported laboratory rates to be in orders of magnitude faster than the natural weathering rates (White, 2009). These discrepancies have mainly been attributed to (i) changes in fluid composition (ii) changes in primary mineral surfaces (reactive sites) and (iii) the formation of secondary phases; that could slow natural weathering rates. It is indeed difficult to measure the interactive effect of the intrinsic factors (e.g. mineral composition, surface area) and extrinsic factors (e.g. solution composition, climate, bioturbation) occurring at the natural setting, in the laboratory experiments. A modeling approach could be useful in this case. A number of geochemical models (e.g. PHREEQC, EQ3/EQ6) already exist and are capable of estimating mineral dissolution / precipitation rates as a function of time and mineral mass. However most of these approaches assume a constant surface area in a given volume of water (White, 2009). This assumption may become invalid especially at long time scales. One of the widely used weathering models is the PROFILE model (Sverdrup and Warfvinge, 1993). The PROFILE model takes into account the mineral composition, solution composition and surface area in determining dissolution / precipitation rates. However there is less coupling with other processes (e.g. physical weathering, clay migration, bioturbation) which could directly or indirectly influence dissolution / precipitation rates. We propose in this study a coupling between chemical weathering mechanism (defined as a function of reactive area, solution composition, temperature, mineral composition) and the physical weathering module in the SoilGen model which calculates the evolution of particle size (used for surface area calculation) as influenced by temperature gradients. The solution composition in the SoilGen model is also influenced by other processes such as atmospheric inputs, organic matter decomposition, cation exchange, secondary mineral formation and leaching. We then apply this coupled mechanism on a case study involving 3 loess soil profiles to analyze the sensitivity of mineral weathering rates to physical weathering. Initial results show some sensitivity but not that dramatic. The less sensitivity was attributed to dominance of resistant primary minerals (> 70% quartz). Scenarios with different sets of mineralogy will be tested and sensitivity results in terms of silicate mineral dissolution rates and CO2-consumption will be presented in the conference. References Sverdrup H and Warfvinge P., 1993. Calculating field weathering rates using a mechanistic geochemical model PROFILE. Applied Geochemistry, 8:273-283. White, A.F., 2009. Natural weathering rates of silicate minerals. In: Drever, J.I. (Ed.), Surface and Ground Water, Weathering and Soils. In: Holland, H.D., Turekian, K.K. (Eds.), Treatise on Geochemistry. vol. 5. Elsevier-Pergamon, Oxford, pp. 133-168.

  18. Gombosi Receives 2013 Space Weather and Nonlinear Waves and Processes Prize: Citation

    NASA Astrophysics Data System (ADS)

    McCoy, Robert P.

    2014-08-01

    The Space Physics and Aeronomy section of AGU awards the Space Weather and Nonlinear Waves and Processes Prize to Tamas Gombosi of the University of Michigan. Gombosi, the founding director of the Center for Space Environment Modeling, has been a leader in space weather research, a visionary in space weather numerical modeling for several decades, and a pioneer of international space physics collaboration. Gombosi's major contributions to space weather include the development of the first time-dependent numerical model of the terrestrial polar wind and the creation of the BATS-R-US magnetohydrodynamic model, a powerful and versatile numerical tool widely used today for modeling the global geospace, the heliosphere, and the solar interior.

  19. Influence of weather-climatic conditions on biospheric processes

    NASA Astrophysics Data System (ADS)

    Govorushko, S. M.

    2012-12-01

    The significance of meteorological processes and phenomena in the biosphere functioning is revealed. The influence of various weather conditions on human health is considered; the factors and mechanisms of their action are described. The impact of meteorological processes on animals is discussed and concrete examples of such impacts are presented. The influence of meteorological processes and phenomena on plants at different stages of their life (pollination, growth, ripening, transport of seeds, damage, and death) and on some abiotic natural components is shown. It is inferred that weather-climatic conditions have a great influence on biospheric processes.

  20. Physical disintegration of biochar: An overlooked process

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Data collected from both artificially and field (naturally) weathered biochar suggest that a potentially significant pathway of biochar disappearance is through physical breakdown of the biochar structure. Through scanning electron microscopy (SEM) we characterized this physical weathering which inc...

  1. Future L5 Missions for Solar Physics and Space Weather

    NASA Astrophysics Data System (ADS)

    Auchere, Frederic; Gopalswamy, Nat

    Coronal mass ejections (CMEs) and corotating interaction regions (CIR) are the sources of intense space weather in the heliosphere. Most of the current knowledge on CMEs accumulated over the past few decades has been derived from observations made from the Sun-Earth line, which is not the ideal vantage point to observe Earth-affecting CMEs (Gopalswamy et al., 2011a,b). In this paper, the advantages of remote-sensing and in-situ observations from the Sun-Earth L5 point are discussed. Locating a mission at Sun-Earth L5 has several key benefits for solar physics and space weather: (1) off the Sun-Earth line view is critical in observing Earth-arriving parts of CMEs, (2) L5 coronagraphic observations can also provide near-Sun space speed of CMEs, which is an important input to models that forecast Earth-arrival time of CMEs, (3) backside and frontside CMEs can be readily distinguished even without inner coronal imagers, (4) preceding CMEs in the path of Earth-affecting CMEs can be identified for a better estimate of the travel time, (5) CIRs reach the L5 point a few days before they arrive at Earth, and hence provide significant lead time before CIR arrival, (6) L5 observations can provide advance knowledge of CME and CIR source regions (coronal holes) rotating to Earth view, and (7) magnetograms obtained from L5 can improve the surface magnetic field distribution used as input to MHD models that predict the background solar wind. The paper also discusses L5 mission concepts that can be achieved in the near future. References Gopalswamy, N., Davila, J. M., St. Cyr, O. C., Sittler, E. C., Auchre, F., Duvall, T. L., Hoeksema, J. T., Maksimovic, M., MacDowall, R. J., Szabo, A., Collier, M. R. (2011a), Earth-Affecting Solar Causes Observatory (EASCO): A potential International Living with a Star Mission from Sun-Earth L5 JASTP 73, 658-663, DOI: 10.1016/j.jastp.2011.01.013 Gopalswamy, N., Davila, J. M., Auchre, F., Schou, J., Korendyke, C. M. Shih, A., Johnston, J. C., MacDowall, R. J., Maksimovic, M., Sittler, E., et al. (2011b), Earth-Affecting Solar Causes Observatory (EASCO): a mission at the Sun-Earth L5, Solar Physics and Space Weather Instrumentation IV. Ed. Fineschi, S. & Fennelly, J., Proceedings of the SPIE, Volume 8148, article id. 81480Z, DOI: 10.1117/12.901538

  2. Weather.

    ERIC Educational Resources Information Center

    Web Feet K-8, 2000

    2000-01-01

    This subject guide to weather resources includes Web sites, CD-ROMs and software, videos, books, audios, magazines, and professional resources. Related disciplines are indicated, age levels are specified, and a student activity is included. (LRW)

  3. An Unusual Process of Accelerated Weathering of a Marly Limestone

    NASA Astrophysics Data System (ADS)

    Ercoli, L.; Rizzo, G.; Algozzini, G.

    2003-04-01

    This work deals with a singular case of stone deterioration, which occurred during the restoration of the Cathedral of Cefal. In particular, a significant process of stone decohesion started after a consolidation treatment on ashlars of the external face of the cloister portico. A study was carried out to characterize the stone and to investigate the deterioration process. Petrographical, chemical and physical analyses were performed on samples taken from the wall. The results indicate that the medieval monument was built using a Pliocene marly limestone, called "trubo", quarried from outcrops of the environs of Cefal. The rock is soft and uniformely cemented. The carbonatic fraction of the rock is due to foraminifera shells; the rock also contains detritic quartz, feldspate and glauconite. The clay minerals, mainly illite and montmorillonite, are widespread in the rock in the form of thin layers. The use of such a stone in a building of relevant artistic value is definitely unusual. In fact, the "trubo" is a rock subjected to natural decay because of its mineralogical composition and fabric; as effect of natural weathering, in the outcrops the rock disaggregates uniformely, producing silt. In the cloister this effect was magnified by extreme environmental conditions (marine spray, severe excursions of both relative humidity and temperature). Furthermore, after soluble salts removing and subsequent consolidation with ethyl silicate, a significant acceleration of the decay process was observed, producing friable scales detach for a depth of about 3 cm into the ashlars. The stone appeared corroded and uneven. Experimental tests were performed in laboratory in order to evidence any origin of incompatibility between such stone composition and the treatments carried out, which on the other hand are the most generally adopted in restoration interventions.

  4. Stealth CMEs: A Challenge for Solar Physics and Space Weather

    NASA Astrophysics Data System (ADS)

    Nitta, N.; Srivastava, N.

    2013-12-01

    It is commonly believed that coronal mass ejections (CMEs) are a primary driver of intense disturbances in the inner heliosphere. Although many of these CMEs are associated with clear solar transient phenomena such as flares, there have been a number of events without unambiguous solar origin, presenting a significant challenge not only for solar physics research, but also for space weather forecasts. For example, nearly 20% of major geomagnetic storms in solar cycle 23 that involved the interplanetary counterparts of CMEs (i.e., ICMEs) did not leave compelling signatures in EUV or X-ray images. We now tend to consider such orphan CMEs to be 'stealth' CMEs as first identified in data from the Solar Terrestrial Relations Observatory (STEREO) during last solar minimum. In the meantime the sensitivity of coronal observations has been tremendously improved as the Solar Dynamics Observatory (SDO) was launched in February 2010; SDO carries the Atmospheric Imaging Assembly (AIA), which provides high-cadence, full-disk images in a broad temperature range as sampled in EUV wavelengths. In principle, AIA should allow us to trace the origin of every Earth-directed CME observed as a limb event by the coronagraphs (COR-1, COR-2, HI-1 and HI-2) on STEREO. In reality, however, we have at least a handful of ICMEs whose origin may not clearly be tracked down to the low corona. Some of them were indeed geo-effective, further complicated by other factors including co-rotating interaction regions (CIRs). Here we give a survey of these events, discussing AIA and STEREO observations of their onsets and propagations in reference to their in-situ manifestations. We list key questions that should be answered by observational and modeling work in order to get more solid understanding of the origin of geomagnetic storms.

  5. Process evaluation: Weatherization Residential Assistance Partnership (WRAP Program). [Final report

    SciTech Connect

    Not Available

    1990-10-01

    The ``Weatherization Residential Assistance Partnership,`` or WRAP program, is a fuel-blind conservation program designed to assist Northeast Utilities` low-income customers to use energy safely and efficiently. Innovative with respect to its collaborative approach and its focus on utilizing and strengthening the existing low-income weatherization service delivery network, and WRAP program offers an interesting model to other utilities which traditionally have relied on for-profit energy service contractors and highly centralized program implementation structures. This report presents the findings of a process evaluation and WRAP customer survey conducted by the Technical Development Corporation (TDC). TDC`s work is one part of a multi-part evaluation project being conducted under the management of ICF Resources, Inc.

  6. Process evaluation: Weatherization Residential Assistance Partnership (WRAP Program)

    SciTech Connect

    Not Available

    1990-10-01

    The Weatherization Residential Assistance Partnership,'' or WRAP program, is a fuel-blind conservation program designed to assist Northeast Utilities' low-income customers to use energy safely and efficiently. Innovative with respect to its collaborative approach and its focus on utilizing and strengthening the existing low-income weatherization service delivery network, and WRAP program offers an interesting model to other utilities which traditionally have relied on for-profit energy service contractors and highly centralized program implementation structures. This report presents the findings of a process evaluation and WRAP customer survey conducted by the Technical Development Corporation (TDC). TDC's work is one part of a multi-part evaluation project being conducted under the management of ICF Resources, Inc.

  7. Anvil Forecast Tool in the Advanced Weather Interactive Processing System

    NASA Technical Reports Server (NTRS)

    Barrett, Joe H., III; Hood, Doris

    2009-01-01

    Meteorologists from the 45th Weather Squadron (45 WS) and National Weather Service Spaceflight Meteorology Group (SMG) have identified anvil forecasting as one of their most challenging tasks when predicting the probability of violations of the Lightning Launch Commit Criteria and Space Shuttle Flight Rules. As a result, the Applied Meteorology Unit (AMU) was tasked to create a graphical overlay tool for the Meteorological Interactive Data Display System (MIDDS) that indicates the threat of thunderstorm anvil clouds, using either observed or model forecast winds as input. The tool creates a graphic depicting the potential location of thunderstorm anvils one, two, and three hours into the future. The locations are based on the average of the upper level observed or forecasted winds. The graphic includes 10 and 20 n mi standoff circles centered at the location of interest, as well as one-, two-, and three-hour arcs in the upwind direction. The arcs extend outward across a 30 sector width based on a previous AMU study that determined thunderstorm anvils move in a direction plus or minus 15 of the upper-level wind direction. The AMU was then tasked to transition the tool to the Advanced Weather Interactive Processing System (AWIPS). SMG later requested the tool be updated to provide more flexibility and quicker access to model data. This presentation describes the work performed by the AMU to transition the tool into AWIPS, as well as the subsequent improvements made to the tool.

  8. Van Allen Probes Science Gateway and Space Weather Data Processing

    NASA Astrophysics Data System (ADS)

    Romeo, G.; Barnes, R. J.; Weiss, M.; Fox, N. J.; Mauk, B.; Potter, M.; Kessel, R.

    2014-12-01

    The Van Allen Probes Science Gateway acts as a centralized interface to the instrument Science Operation Centers (SOCs), provides mission planning tools, and hosts a number of science related activities such as the mission bibliography. Most importantly, the Gateway acts as the primary site for processing and delivering the VAP Space Weather data to users. Over the past year, the web-site has been completely redesigned with the focus on easier navigation and improvements of the existing tools such as the orbit plotter, position calculator and magnetic footprint tool. In addition, a new data plotting facility has been added. Based on HTML5, which allows users to interactively plot Van Allen Probes summary and space weather data. The user can tailor the tool to display exactly the plot they wish to see and then share this with other users via either a URL or by QR code. Various types of plots can be created, including simple time series, data plotted as a function of orbital location, and time versus L-Shell. We discuss the new Van Allen Probes Science Gateway and the Space Weather Data Pipeline.

  9. Structural control of weathering processes within exhumed granitoids: Compartmentalisation of geophysical properties by faults and fractures

    NASA Astrophysics Data System (ADS)

    Place, J.; Géraud, Y.; Diraison, M.; Herquel, G.; Edel, J.-B.; Bano, M.; Le Garzic, E.; Walter, B.

    2016-03-01

    In the latter stages of exhumation processes, rocks undergo weathering. Weathering halos have been described in the vicinity of structures such as faults, veins or dykes, with a lateral size gradually narrowing with depth, symmetrically around the structures. In this paper, we describe the geophysical characterisation of such alteration patterns on two granitoid outcrops of the Catalan Coastal Ranges (Spain), each of which is affected by one major fault, as well as minor faults and fractures. Seismic, electric and ground penetrating radar surveys were carried out to map the spatial distribution of P-wave velocity, electrical resistivity and to identify reflectors of electromagnetic waves. The analysis of this multi-method and complementary dataset revealed that, at shallow depth, geophysical properties of the materials are compartmentalised and asymmetric with respect to major and subsidiary faults affecting the rock mass. This compartmentalisation and asymmetry both tend to attenuate with depth, whereas the effect of weathering is more symmetric with respect to the major structure of the outcrops. We interpret such compartmentalisation as resulting from the role of hydraulic and mechanical boundaries played by subsidiary faults, which tend to govern both the chemical and physical alterations involved in weathering. Thus, the smoothly narrowing halo model is not always accurate, as weathering halos can be strongly asymmetrical and present highly irregular contours delimiting sharp contrasts of geophysical properties. These results should be considered when investigating and modelling fluid storage and transfer in top crystalline rock settings for groundwater applications, hydrocarbon or geothermal reservoirs, as well as mineral deposits.

  10. Assessing the Effects of Weather Conditions on Physical Activity Participation Using Objective Measures

    PubMed Central

    Chan, Catherine B.; Ryan, Daniel A.

    2009-01-01

    Habitual physical activity is an important determinant of health, yet many people are considered to be inactive. Identification of the obstacles to greater participation is necessary for the development of strategies to overcome those obstacles. The weather has been identified as a perceived barrier to participation in physical activity, but exactly which adverse weather conditions are most important, and the extent to which they contribute to decreases in physical activity have rarely been quantified in populations. In the past decade, a small number of studies have used publicly available databases to examine the quantitative effects of weather (e.g., temperature, precipitation, wind) on physical activity in children, adolescents and adults. This review examines our historical, qualitative versus emerging, quantitative understanding of how specific weather conditions affect a population’s activity. PMID:20054460

  11. The physics of Martian weather and climate: a review.

    PubMed

    Read, P L; Lewis, S R; Mulholland, D P

    2015-12-01

    The planet Mars hosts an atmosphere that is perhaps the closest in terms of its meteorology and climate to that of the Earth. But Mars differs from Earth in its greater distance from the Sun, its smaller size, its lack of liquid oceans and its thinner atmosphere, composed mainly of CO2. These factors give Mars a rather different climate to that of the Earth. In this article we review various aspects of the martian climate system from a physicist's viewpoint, focusing on the processes that control the martian environment and comparing these with corresponding processes on Earth. These include the radiative and thermodynamical processes that determine the surface temperature and vertical structure of the atmosphere, the fluid dynamics of its atmospheric motions, and the key cycles of mineral dust and volatile transport. In many ways, the climate of Mars is as complicated and diverse as that of the Earth, with complex nonlinear feedbacks that affect its response to variations in external forcing. Recent work has shown that the martian climate is anything but static, but is almost certainly in a continual state of transient response to slowly varying insolation associated with cyclic variations in its orbit and rotation. We conclude with a discussion of the physical processes underlying these long- term climate variations on Mars, and an overview of some of the most intriguing outstanding problems that should be a focus for future observational and theoretical studies. PMID:26534887

  12. The physics of Martian weather and climate: a review

    NASA Astrophysics Data System (ADS)

    Read, P. L.; Lewis, S. R.; Mulholland, D. P.

    2015-12-01

    The planet Mars hosts an atmosphere that is perhaps the closest in terms of its meteorology and climate to that of the Earth. But Mars differs from Earth in its greater distance from the Sun, its smaller size, its lack of liquid oceans and its thinner atmosphere, composed mainly of CO2. These factors give Mars a rather different climate to that of the Earth. In this article we review various aspects of the martian climate system from a physicists viewpoint, focusing on the processes that control the martian environment and comparing these with corresponding processes on Earth. These include the radiative and thermodynamical processes that determine the surface temperature and vertical structure of the atmosphere, the fluid dynamics of its atmospheric motions, and the key cycles of mineral dust and volatile transport. In many ways, the climate of Mars is as complicated and diverse as that of the Earth, with complex nonlinear feedbacks that affect its response to variations in external forcing. Recent work has shown that the martian climate is anything but static, but is almost certainly in a continual state of transient response to slowly varying insolation associated with cyclic variations in its orbit and rotation. We conclude with a discussion of the physical processes underlying these long- term climate variations on Mars, and an overview of some of the most intriguing outstanding problems that should be a focus for future observational and theoretical studies.

  13. Evidence for Physical Weathering of Iron Meteorite Meridiani Planum (Heat Shield Rock) on Mars

    NASA Astrophysics Data System (ADS)

    Ashley, J. W.; McCoy, T. J.; Schrder, C.

    2009-12-01

    Meteorites on the surfaces of other solar system bodies can provide natural experiments for monitoring weathering processes. In the case of Mars, clues to the more subtle aspects of water occurrence and reaction may be revealed by the effects of highly sensitive aqueous alteration processes, while physical processes may be recorded through aeolian abrasion effects. Over the past 2000 sols, the two Mars Exploration Rover (MER) spacecraft have formally identified a minimum of 11 meteorite candidates [1-3], with many more unofficial candidates likely, posing an intriguing set of questions concerning their chemical, mineralogical, and morphological conditions. Five meteorite candidates, including the newly discovered MER-B rock Block Island, and one confirmed meteorite [Meridiani Planum (MP; originally Heat Shield Rock)] [4] have been investigated with the rover arm instruments. All contain levels of ferric iron, which should not be present in pristine samples (i.e. without fusion crust and/or alteration phases). Moreover, preliminary morphologic evidence contributes to the case of possible chemical weathering in Block Island. Scrutiny of a Microscopic Imager (MI) mosaic of MP shows clear evidence for both localized aeolian sculpting, and the Widmansttten pattern common to sliced and acid-etched surfaces of many iron-nickel meteorites. These latter features are manifest as millimeter-sized chevrons and subparallel linearities, most prominent across a partially brushed surface approximately 3 x 2 cm in area. Similar patterns are observed on a number of hot and cold desert meteorites (e.g. Drum Mountain and Ft. Stockton), and are attributed to physical ablation by sand grains differentially weathering the kamacite and taenite lamellae within the rock. A similar or identical process is interpreted as responsible for the features observed in MP. Other macro-scale features on MP are of questionable weathering origin. While some prefer a regmaglypt interpretation for the cavities in MP, others question whether differential weathering (either aqueous or physical) of softer sulfide (troilite) nodules or other inclusions such as schreibersite [5] in the metal matrix may be at least partly responsible. A discontinuous coating of darker material, interpreted to be oxide (though it is uncertain whether this is relict fusion crust or weathering rind), appears in the MI images also to have been polished and sculpted by abrasive forces. Laboratory experiments designed to address the requirements for iron shaping by wind abrasion would help provide constraints on the wind velocities involved in these processes. Preliminary results for Block Island display many features that are also consistent with aeolian abrasion. References: [1] Schrder C. et al. (2008) JGR 113, E06S22, doi:10.1029/2007JE002990. [2] Ashley J. W. et al. (2009) LPSC XL. [3] Schrder C. et al. (2009) LPSC XL. [4] Connolly H.C.J. et al. (2006) Meteoritical Bulletin #90, Meteoritics and Planet Sci. 41(9): p. 1383-1418. [5] Fleischer I. et al. (2009) Meteoritics and Planet Sci. 44, p. A70.

  14. Evidence of Space Weathering Processes Across the Surface of Vesta

    NASA Technical Reports Server (NTRS)

    Pieters, Carle M.; Blewett, David T.; Gaffey, Michael; Mittlefehldt, David W.; CristinaDeSanctis, Maria; Reddy, Vishnu; Coradini, Angioletta; Nathues, Andreas; Denevi, Brett W.; Li, Jian-Yang; McCord, Thomas B.; Marchi, Simone; Palmer, Eric E.; Sunshine, Jessica M.; Filacchione, Gianrico; Ammannito, Eleonora; Raymond, Carol A.; Russell, Christopher T.

    2011-01-01

    As NASA s Dawn spacecraft explores the surface of Vesta, it has become abundantly clear that Vesta is like no other planetary body visited to date. Dawn is collecting global data at increasingly higher spatial resolution during its one-year orbital mission. The bulk properties of Vesta have previously been linked to the HED meteorites through remote mineral characterization of its surface from Earth-based spectroscopy. A principal puzzle has been why Vesta exhibits relatively unweathered diagnostic optical features compared to other large asteroids. Is this due to the composition of this proto-planet or the space environment at Vesta? Alteration or weathering of materials in space normally develops as the products of several processes accumulate on the surface or in an evolving particulate regolith, transforming the bedrock into fragmental material with properties that may be measurably different from the original. Data from Dawn reveal that the regolith of Vesta is exceptionally diverse. Regional surface units are observed that have not been erased by weathering with time. Several morphologically-fresh craters have excavated bright, mafic-rich materials and exhibit bright ray systems. Some of the larger craters have surrounding subdued regions (often asymmetric) that are lower in albedo and relatively red-sloped in the visible while exhibiting weaker mafic signatures. Several other prominent craters have rim exposures containing very dark material and/or display a system of prominent dark rays. Most, but not all, dark areas associated with craters exhibit significantly lower spectral contrast, suggesting that either a Vesta lithology with an opaque component has been exposed locally or that the surface has been contaminated by a relatively dark impactor. Similarly, most, but not all, bright areas associated with craters exhibit enhanced mafic signatures compared to surroundings. On a regional scale, the large south polar structure and surrounding terrain exhibit relatively strong mafic absorption features, suggesting either a concentration of mafic materials or that materials exposed have been less affected by space weathering products. These combined initial observations indicate some space weathering processes are active in this part of the main asteroid belt, but are highly variable across the surface of Vesta. Such processes include: impacts from wandering asteroidal debris and local mixing at both micro- and macro-scales, irradiation by solar wind and galactic particles, production and distribution of impact breccias or melt products, and local movement of materials to gravity lows (gradual as well as sudden).

  15. Distinctive space weathering on Vesta from regolith mixing processes.

    PubMed

    Pieters, C M; Ammannito, E; Blewett, D T; Denevi, B W; De Sanctis, M C; Gaffey, M J; Le Corre, L; Li, J-Y; Marchi, S; McCord, T B; McFadden, L A; Mittlefehldt, D W; Nathues, A; Palmer, E; Reddy, V; Raymond, C A; Russell, C T

    2012-11-01

    The surface of the asteroid Vesta has prominent near-infrared absorption bands characteristic of a range of pyroxenes, confirming a direct link to the basaltic howardite-eucrite-diogenite class of meteorites. Processes active in the space environment produce 'space weathering' products that substantially weaken or mask such diagnostic absorption on airless bodies observed elsewhere, and it has long been a mystery why Vesta's absorption bands are so strong. Analyses of soil samples from both the Moon and the asteroid Itokawa determined that nanophase metallic particles (commonly nanophase iron) accumulate on the rims of regolith grains with time, accounting for an observed optical degradation. These nanophase particles, believed to be related to solar wind and micrometeoroid bombardment processes, leave unique spectroscopic signatures that can be measured remotely but require sufficient spatial resolution to discern the geologic context and history of the surface, which has not been achieved for Vesta until now. Here we report that Vesta shows its own form of space weathering, which is quite different from that of other airless bodies visited. No evidence is detected on Vesta for accumulation of lunar-like nanophase iron on regolith particles, even though distinct material exposed at several fresh craters becomes gradually masked and fades into the background as the craters age. Instead, spectroscopic data reveal that on Vesta a locally homogenized upper regolith is generated with time through small-scale mixing of diverse surface components. PMID:23128227

  16. Space Weathering on 4 Vesta: Processes and Products

    NASA Technical Reports Server (NTRS)

    Pieters, C. M.; Blewett, D. T.; Gaffey, M.; Mittlefehldt, D. W.; De Sanctis, M. C.; Reddy, V.; Nathues, A.; Denevi, B. W.; Li, J. Y.; McCord, T. B.; Marchi, S.; Palmer, E. E.; Sunshine, J. M.; Ammannito, E.; Raymond, C. A.; Russell, C. T.

    2012-01-01

    The bulk properties of Vesta have previously been linked directly to the howardite, eucrite, and diogenite (HED) meteorites through remote mineral characterization of its surface from Earth-based spectroscopy [e.g., 1]. A long-standing enigma has been why does Vesta s surface appear to have suffered so little alteration from the space environment, whereas materials exposed on the Moon and some S-type asteroids are significantly changed (grains develop rims containing nano-phase opaques [e.g. 2]). The Dawn spacecraft is well suited to address this issue and is half through its extended mapping phase of this remarkable proto-planet [3]. On a local scale Dawn sees evidence of recent exposures at craters, but distinctive surface materials blend into background at older craters. The presence of space weathering processes are thus evident at Vesta, but the character and form are controlled by the unique environment and geologic history of this small body.

  17. Weathering processes implied from analysis of small Martian avalanche chutes

    NASA Technical Reports Server (NTRS)

    Sullivan, R.

    1992-01-01

    It has been proposed that the smaller features of martian spur and gully slope morphology, located along the upper walls of Valles Marineris, are avalanche chutes. A three-dimensional stability back-analysis technique was developed and applied to these small avalanche chutes, yielding average values of cohesion and angle of internal friction for the mobile layer materials on these slopes at the time of each slope failure. Generally, the analysis showed that at the time of each slope failure material strengths had been reduced to those of moderately cohesive debris down through depths of tens of meters. These results have implications and possible constraints for the nature and rate of martian weathering processes.

  18. Planetary surface weathering

    NASA Technical Reports Server (NTRS)

    Gooding, J. L.

    1986-01-01

    The weathering of planetary surfaces is treated. Both physical and chemical weathering (reactions between minerals or mineraloids and planetary volatiles through oxidation, hydration, carbonation, or solution processes) are discussed. Venus, earth, and Mars all possess permanent atmospheres such that weathering should be expected to significantly affect their respective surfaces. In contrast, Mercury and the moon lack permanent atmospheres but conceivably could experience surface weathering in response to transient atmospheres generated by volcanic or impact cratering events. Weathering processes can be postulated for other rocky objects including Io, Titan, asteroids, and comets.

  19. wradlib - an Open Source Library for Weather Radar Data Processing

    NASA Astrophysics Data System (ADS)

    Pfaff, Thomas; Heistermann, Maik; Jacobi, Stephan

    2014-05-01

    Even though weather radar holds great promise for the hydrological sciences, offering precipitation estimates with unrivaled spatial and temporal resolution, there are still problems impeding its widespread use, among which are: almost every radar data set comes with a different data format with public reading software being available only rarely. standard products as issued by the meteorological services often do not serve the needs of original research, having either too many or too few corrections applied. Especially when new correction methods are to be developed, researchers are often forced to start from scratch having to implement many corrections in addition to those they are actually interested in. many algorithms published in the literature cannot be recreated using the corresponding article only. Public codes, providing insight into the actual implementation and how an approach deals with possible exceptions are rare. the radial scanning setup of weather radar measurements produces additional challenges, when it comes to visualization or georeferencing of this type of data. Based on these experiences, and in the hope to spare others at least some of these tedious tasks, wradlib offers the results of the author's own efforts and a growing number of community-supplied methods. wradlib is designed as a Python library of functions and classes to assist users in their analysis of weather radar data. It provides solutions for all tasks along a typical processing chain leading from raw reflectivity data to corrected, georeferenced and possibly gauge adjusted quantitative precipitation estimates. There are modules for data input/output, data transformation including Z/R transformation, clutter identification, attenuation correction, dual polarization and differential phase processing, interpolation, georeferencing, compositing, gauge adjustment, verification and visualization. The interpreted nature of the Python programming language makes wradlib an ideal tool for interactive data exploration and analysis. Based on the powerful scientific python stack (numpy, scipy, matplotlib) and in parts augmented by functions compiled in C or Fortran, most routines are fast enough to also allow data intensive re-analyses or even real-time applications. From the organizational point of view, wradlib is intended to be community driven. To this end, the source code is made available using a distributed version control system (DVCS) with a publicly hosted repository. Code may be contributed using the fork/pull-request mechanism available to most modern DVCS. Mailing lists were set up to allow dedicated exchange among users and developers in order to fix problems and discuss new developments. Extensive documentation is a key feature of the library, and is available online at http://wradlib.bitbucket.org. It includes an individual function reference as well as examples, tutorials and recipes, showing how those routines can be combined to create complete processing workflows. This should allow new users to achieve results quickly, even without much prior experience with weather radar data.

  20. Anvil Tool in the Advanced Weather Interactive Processing System

    NASA Technical Reports Server (NTRS)

    Barrett, Joe, III; Bauman, William, III; Keen, Jeremy

    2007-01-01

    Meteorologists from the 45th Weather Squadron (45 WS) and Spaceflight Meteorology Group (SMG) have identified anvil forecasting as one of their most challenging tasks when predicting the probability of violations of the lightning Launch Commit Criteria and Space Shuttle Flight Rules. As a result, the Applied Meteorology Unit (AMU) created a graphical overlay tool for the Meteorological Interactive Data Display Systems (MIDDS) to indicate the threat of thunderstorm anvil clouds, using either observed or model forecast winds as input. In order for the Anvil Tool to remain available to the meteorologists, the AMU was tasked to transition the tool to the Advanced Weather interactive Processing System (AWIPS). This report describes the work done by the AMU to develop the Anvil Tool for AWIPS to create a graphical overlay depicting the threat from thunderstorm anvil clouds. The AWIPS Anvil Tool is based on the previously deployed AMU MIDDS Anvil Tool. SMG and 45 WS forecasters have used the MIDDS Anvil Tool during launch and landing operations. SMG's primary weather analysis and display system is now AWIPS and the 45 WS has plans to replace MIDDS with AWIPS. The Anvil Tool creates a graphic that users can overlay on satellite or radar imagery to depict the potential location of thunderstorm anvils one, two, and three hours into the future. The locations are based on an average of the upper-level observed or forecasted winds. The graphic includes 10 and 20 nm standoff circles centered at the location of interest, in addition to one-, two-, and three-hour arcs in the upwind direction. The arcs extend outward across a 30 degree sector width based on a previous AMU study which determined thunderstorm anvils move in a direction plus or minus 15 degrees of the upper-level (300- to 150-mb) wind direction. This report briefly describes the history of the MIDDS Anvil Tool and then explains how the initial development of the AWIPS Anvil Tool was carried out. After testing was performed by SMG, 45 WS, and AMU, a number of needed improvements were identified. A bug report document was created that showed the status of each bug and desired improvement. This report lists the improvements that were made to increase the accuracy and user-friendliness of the tool. Final testing was carried out and documented and then the final version of the software and Users Guide was provided to SMG and the 45 WS. Several possible future improvements to the tool are identified that would increase the flexibility of the tool. This report contains a brief history of the development of the Anvil Tool in MIDDS, and then describes the transition and development of software to AWIPS.

  1. The Space Physics of Life: Searching for Biosignatures on Habitable Icy Worlds Affected by Space Weathering

    NASA Technical Reports Server (NTRS)

    Cooper, John F.

    2006-01-01

    Accessible surfaces of the most likely astrobiological habitats (Mars, Europa, Titan) in the solar system beyond Earth are exposed to various chemical and hydrologic weathering processes directly or indirectly induced by interaction with the overlying space environment. These processes can be both beneficial, through provision of chemical compounds and energy, and destructive, through chemical dissociation or burial, to detectable presence of biosignatures. Orbital, suborbital, and surface platforms carrying astrobiological instrumentation must survive, and preferably exploit, space environment interactions to reach these habitats and search for evidence of life or its precursors. Experience from Mars suggests that any detection of biosignatures must be accompanied by characterization of the local chemical environment and energy sources including irradiation by solar ultraviolet photons and energetic particles from the space environment. Orbital and suborbital surveys of surface chemistry and astrobiological potential in the context of the space environment should precede targeted in-situ measurements to maximize probability of biosignature detection through site selection. The Space Physics of Life (SPOL) investigation has recently been proposed to the NASA Astrobiology Institute and is briefly described in this presentation. SPOL is the astrobiologically relevant study of the interactions and relationships of potentially? or previously inhabited, bodies of the solar system with the surrounding environments. This requires an interdisciplinary effort in space physics, planetary science, and radiation biology. The proposed investigation addresses the search for habitable environments, chemical resources to support life, and techniques for detection of organic and inorganic signs of life in the context of the space environment.

  2. Zeolite Formation and Weathering Processes in Dry Valleys of Antartica: Martian Analogs

    NASA Technical Reports Server (NTRS)

    Gibson, E. K., Jr.; Wentworth, S. J.; McKay, D. S.; Socki, R. A.

    2004-01-01

    Terrestrial weathering processes in cold-desert climates such as the Dry Valleys of Antarctica may provide an excellent analog to chemical weathering and diagenesis of soils on Mars. Detailed studies of soil development and the chemical and mineralogical alterations occurring within soil columns in Wright Valley, Antarctica show incredible complexity in the upper meter of soil. Previous workers noted the ice-free Dry Valleys are the best terrestrial approximations to contemporary Mars. Images returned from the Pathfinder and Spirit landers show similarities to surfaces observed within the Dry Valleys. Similarities to Mars that exist in these valleys are: mean temperatures always below freezing (-20 C), no rainfall, sparse snowfall-rapidly removed by sublimation, desiccating winds, diurnal freeze-thaw cycles (even during daylight hours), low humidity, oxidative environment, relatively high solar radiation and low magnetic fields . The Dry Valley soils contain irregular distributions and low abundances of soil microorganisms that are somewhat unusual on Earth. Physical processes-such as sand abrasion-are dominant mechanisms of rock weathering in Antarctica. However, chemical weathering is also an important process even in such extreme climates. For example, ionic migration occurs even in frozen soils along liquid films on individual soil particles. It has also been shown that water with liquid-like properties is present in soils at temperatures on the order of approx.-80 C and it has been observed that the percentage of oxidized iron increases with increasing soil age and enrichments in oxidized iron occurs toward the surface. The presence of evaporates is evident and appear similar to "evaporite sites" within the Pathfinder and Spirit sites. Evaporites indicate ionic migration and chemical activity even in the permanently frozen zone. The presence of evaporates indicates that chemical weathering of rocks and possibly soils has been active. Authogenic zeolites have been identified within the soil columns because they are fragile; i.e. they are euhedral, unabraded, and unfractured, strongly suggesting in situ formation. Their presence in Antarctic samples is another indication that diagenic processes are active in cold-desert environments. The presence of zeolites, and other clays along with halites, sulfates, carbonates, and hydrates are to be expected within the soil columns on Mars at the Gusev and Isidis Planitia regions. The presence of such water-bearing minerals beneath the surface supplies one of the requirements to support biological activity on Mars.

  3. The Effects of Daily Weather on Accelerometer-measured Physical Activity among Adults with Arthritis

    PubMed Central

    Feinglass, Joe; Lee, Julia; Dunlop, Dorothy; Song, Jing; Semanik, Pam; Chang, Rowland W.

    2010-01-01

    Background This study analyzes Chicago-area weather effects on objectively measured physical activity over a three year period among a cohort of 241 participants in an on-going arthritis physical activity trial. Methods Uniaxial accelerometer counts and interview data were analyzed for up to six weekly study waves involving 4823 days of wear. The effects of temperature, rainfall, snowfall and daylight hours were analyzed after controlling for participant characteristics, day of the week, and daily accelerometer wear hours in a mixed effects linear regression model. Results Daylight hours, mean daily temperature <20 or ? 75 degrees and light or heavy rainfall (but not snowfall) were all significantly associated with lower physical activity after controlling for the significant effects of weekends, accelerometer wear hours, age, sex, type of arthritis, employment, Hispanic ethnicity, obesity, and SF36 physical and mental health scores. Conclusions The cumulative effects of weather are reflected in a 38.3% mean monthly difference in daily counts between November and June, reflecting over three additional hours of sedentary time. Physical activity promotion programs for older persons with chronic conditions need lifestyle physical activity plans adapted to weather extremes. PMID:21885884

  4. Novel predictors of soil genesis following natural weathering processes of bauxite residues.

    PubMed

    Zhu, Feng; Xue, Shengguo; Hartley, William; Huang, Ling; Wu, Chuan; Li, Xiaofei

    2016-02-01

    Bauxite residue often has chemical and physical limitations to support plant growth, and improving its matrix properties is crucial to support sustainable vegetation in the long term. Spontaneous vegetation colonization on deposits in Central China, over a period of 20 years, has revealed that natural weathering processes may convert bauxite residue to a soil-like medium. Residue samples from different stacking ages were collected to determine the effect of natural processes on matrix properties over time. It was demonstrated that natural processes decreased pH (10.98 to 9.45), electrical conductivity (EC) (3.73 to 0.36 mS/cm), and exchangeable sodium percentage (ESP) (72.51 to 28.99 %), while increasing bulk density (1.91 to 1.39 g/cm(3)), improving the mean weight diameter (MWD) of water-stable aggregates (0.24 to 0.52 mm), and the proportion of >0.25-mm water-stable aggregates (19.91 to 50.73 %). The accumulation of organic carbon and the reduction of ESP and exchangeable Na had positive effects on soil aggregate formation, while exchangeable Ca and Mg were significantly beneficial to aggregation of water-stable aggregates. Climate, stacking time, and biological factors appear to improve the structure of bauxite residue. Our findings demonstrate soil genesis occurring following natural weathering processes of bauxite residues over time. PMID:26452661

  5. Understanding Magnetic Reconnection: The Physical Mechanism Driving Space Weather

    NASA Astrophysics Data System (ADS)

    Black, Carrie; Antiochos, Spiro K.; Karpen, Judith T.; Germaschewski, Kai; Bessho, Naoki

    2015-04-01

    The explosive energy release in solar eruptive events is believed to be due to magnetic reconnection. In the standard model for coronal mass ejections (CME) and/or solar flares, the free energy for the event resides in the strongly sheared magnetic field of a filament channel. The pre-eruption force balance consists of an upward force due to the magnetic pressure of the sheared field countered by the downward tension of the overlying unsheared field. Magnetic reconnection disrupts this force balance. Therefore, to understand CME/flare initiation, it is critical to model the onset of reconnection driven by the build-up of magnetic shear. In MHD simulations, the application of a magnetic-field shear is trivial. However, kinetic effects are important in the diffusion region and thus, it is important to examine this process with PIC simulations as well. The implementation of such a driver in PIC methods is nontrivial, however, and indicates the necessity of a true multiscale model for such processes in the solar environment. The field must be sheared self-consistently and indirectly to prevent the generation of waves that destroy the desired system. In the work presented here, we show reconnection in an X-Point geometry due to a velocity shear driver perpendicular to the plane of reconnection.This material is based upon work supported by the National Science Foundation under Award No. AGS-1331356 and NASA's Living With a Star Targeted Research and Technology program.

  6. Transitioning From Space Physics Research to Space Weather Application at The Johns Hopkins University Applied Physics Laboratory (JHU/APL)

    NASA Astrophysics Data System (ADS)

    Meng, C. I.

    2003-12-01

    The ability to monitor and predict our near-Earth space environment ("space weather") lags its sister discipline of terrestrial weather studies by years, in both observational and forecast capabilities. However, with current rapid progress in space physics research, and with current and near-future space environment sensors on research and operational satellites, the space weather operational community can reach new levels of maturity. A rapid transition of scientific research results into prototype operational products is especially important. This paper addresses the concept of rapid transition and presents examples carried out recently by scientists at JHU/APL, such as: OVATION (Oval Variation, Assessment, Tracking, Intensity and Online Nowcasting), and real-time geomagnetic activity nowcasting using observations from limited ground magnetometer stations. Several potential future application projects will be discussed as well; these space-environment products are designed to coincide with operationally significant events, such as communication outages or space object tracking.

  7. The Evolution of Soil Hydrological and Physical Properties under the Impact of Mineral Weathering and Organic Matter Sequestration

    NASA Astrophysics Data System (ADS)

    Tan, F.; Lunn, E.; Fisher, B.; Yoo, K.; Imhoff, P. T.; Michael, H. A.

    2014-12-01

    Soil water characteristic (SWC) curve is important for modeling unsaturated flow and reactive transport. SWC also likely influences mineral weathering by affecting water-mineral interactions in the critical zone. The depth profiles of SWC could form as a result of long-term chemical weathering and physical erosion processes. We measured SWCs on samples collected from soil pit and drill cores which captured the weathering profiles from ground surface to slightly weathered bedrock (~7m depth) on a hillslope in Laurel Preserve in West Chester, PA. The weathering profile represents the co-evolution of hydrological and physical properties with varied degrees of weathering and organic matter (OM) content. A WP4C Dewpoint Potentiameter was used to obtain the SWCs (matric potential range: -300 ~ -1.5MPa) for original and OM-removed samples, where OM was removed by heating samples to 350? for 24 h. From the WP4C measurement, soil samples from shallower depths (?44cm) retained more water at a given matric potential, with water contents at shallower depths generally ~2-3 times more than that for saprolite samples from deeper depths at similar matric potentials, indicating that soil water retention increased with degree of weathering. The SWCs measured by WP4C were used to estimate the specific surface area (SSA) using the Tuller and Or (TO) model (Tuller and Or, 2005) , which is based on the assumption that water forms a film on micropore surfaces at the dry end (matric potential ? -1.5MPa). The SSA estimation from the TO model followed the same trend as SSA measured with the N2-BET method. However, the estimated SSA was greater than BET-based SSA, indicating possible underestimation of SSA by the N2-BET method. The comparison of SWC and SSA between original and OM-removed samples indicated the presence of a threshold depth of ~40cm. At depths shallower than 40cm, especially at A horizon (OM ? 9.5Wt%), OM removal significantly decreased estimated SSA and water content at similar matric potentials, while at deeper depths (OM ? 2.7Wt%), the OM-removal treatment resulted in either no change or a slight increase in SSA. The possible existence of a threshold depth indicates that the interactions between OM-mineral sorption and water-mineral interaction differ with depth and are particularly strong within OM-rich surface soils.

  8. Image processing for hazard recognition in on-board weather radar

    NASA Technical Reports Server (NTRS)

    Kelly, Wallace E. (Inventor); Rand, Timothy W. (Inventor); Uckun, Serdar (Inventor); Ruokangas, Corinne C. (Inventor)

    2003-01-01

    A method of providing weather radar images to a user includes obtaining radar image data corresponding to a weather radar image to be displayed. The radar image data is image processed to identify a feature of the weather radar image which is potentially indicative of a hazardous weather condition. The weather radar image is displayed to the user along with a notification of the existence of the feature which is potentially indicative of the hazardous weather condition. Notification can take the form of textual information regarding the feature, including feature type and proximity information. Notification can also take the form of visually highlighting the feature, for example by forming a visual border around the feature. Other forms of notification can also be used.

  9. Interplay between physical movements of soils and mineral grains and chemical weathering

    NASA Astrophysics Data System (ADS)

    Yoo, K.

    2007-12-01

    Most soil biogeochemistry studies treat the soils and their inorganic and organic constituents as physically immobile. Those soil materials, however, are in perpetual motion due to the conversion of bedrock to soils, colluvial transport, and vertical mixing by various biophysical perturbations of the soils. Subsequently, a soil is continuously replaced by the materials from the neighboring soils and the underlying parent material, while its individual horizons are gradually mixed with the materials in the neighboring horizons. The movements of bulk soil materials are ultimately driven by moving individual mineral grains. While rarely appreciated, these physical movements of soil's mineral components operate in the presence of strong vertical and topographic gradients of the rates of mineral dissolution and leaching. The result is that the physical movement of soil constituents affects chemical weathering. The fluxes of soil materials (via physical movements and solute fluxes) in and out of a soil system defined by a researcher determine the time length that the materials reside in the system. The residence time, together with the system-specific rates of chemical weathering, determine the degree of weathering of the materials within the system. This presentation provides a new mathematical framework to consistently quantify the residence times of minerals, individual soil horizons, soil profiles, and an entire soil within a watershed boundary. Soil age, which is equivalent of the time length since the cessation of erosion or deposition on level grounds, becomes a special case of the residence time. The model is combined with empirical data to quantitatively illustrate the impacts that the physical motion of soil constituents have on the rates of chemical weathering. The data are drawn from ongoing field and laboratory studies focusing on the impact of river incision, colluvial flux, bioturbation, and agricultural tillage on the vertical and lateral variation of elemental composition within the soils.

  10. Rock weathering processes and landform development in the Sr Rondane Mountains, Antarctica

    NASA Astrophysics Data System (ADS)

    Matsuoka, Norikazu

    1995-07-01

    Field observations of weathering processes and the related landforms, combined with laboratory analyses of weathering products, permit a synthetic evaluation of Late Cenozoic weathering environments in the Sr Rondane Mountains, Antarctica, an arid upland characterized by low temperatures and strong winds. Rates and character of weathering depend mainly on moisture availability and the bedrock geology. Under the humid weathering regime that occurs only locally around the margin of the present sheet, frequent diurnal freeze-thaw cycles in summer cause relatively rapid rock fragmentation. Most of the mountains are situated in the arid weathering regime, under which rock breakdown is very slow unless the rock contains plenty of salts. Salt weathering becomes more intensive and extensive with exposure age, as a result of salt accumulation in rock, eventually producing soils as small as fine-silt size. Lack of clay mineralization even in weathered rocks having been exposed above the ice sheet prior to 4 Ma ago indicates that hydrolysis or carbonation of rock minerals has been insignificant during the past 4 Ma. The final products of weathering are due mainly to salt action and reflect the parent lithology. Resistant fine-grained granite forms strongly oxidized tors carved with tafoni, or fields of mushroom-like boulders overlying the fractured bedrock. Less resistant rocks, like biotite gneiss and amphibolite, produce stone pavements underlain by saline, silty soils up to 30-40 cm thick, the thickness of which corresponds to the maximum thaw depth.

  11. Physical Activity–Related and Weather-Related Practices of Child Care Centers From 2 States

    PubMed Central

    Ball, Sarah C.; Gillman, Matthew W.; Mayhew, Meghan; Brouwer, Rebecca J. Namenek; Neelon, Sara Benjamin

    2015-01-01

    Background Young children’s physical activity (PA) is influenced by their child care environment. This study assessed PA practices in centers from Massachusetts (MA) and Rhode Island (RI), compared them to best practice recommendations, and assessed differences between states and center profit status. We also assessed weather-related practices. Methods Sixty percent of MA and 54% of RI directors returned a survey, for a total of 254. Recommendations were 1) daily outdoor play, 2) providing outdoor play area, 3) limiting fixed play structures, 4) variety of portable play equipment, and 5) providing indoor play area. We fit multivariable linear regression models to examine adjusted associations between state, profit status, PA, and weather-related practices. Results MA did not differ from RI in meeting PA recommendations (β = 0.03; 0.15, 0.21; P = .72), but MA centers scored higher on weather-related practices (β = 0.47; 0.16, 0.79; P = .004). For-profit centers had lower PA scores compared with nonprofits (β = −0.20; 95% CI: −0.38, −0.02; P = .03), but they did not differ for weather (β = 0.12; −0.19, 0.44; P = .44). Conclusions More MA centers allowed children outside in light rain or snow. For-profit centers had more equipment—both fixed and portable. Results from this study may help inform interventions to increase PA in children. PMID:24763142

  12. Weathering processes and pickeringite formation in a sulfidic schist: a consideration in acid precipitation neutralization studies

    SciTech Connect

    Parnell, R.A. Jr.

    1983-01-01

    Extremely low abrasion pH values (2.8-3.3) characterize the weathering products of the Partridge Formation, a Middle-Ordovician metamorphosed, black, sulfidic shale. The local occurrence is observed of two sulfates that are rare in the Northeast: pickeringite and jarosite. X-ray diffraction studies of the weathering residues and the sulfate efflorescences have also identified dioctahedral and trioctahedral illite, kaolinite, vermiculite, and an 11-12 Angstrom phase, thought to be a type of randomly-interstratified biotite-vermiculite. From the mineralogical studies, qualitative weathering processes for the schist are formulated. A probable mechanism for the intense chemical weathering of the schist appears to be oxidation of iron sulfides to form iron oxide-hydroxides, sulfates, and sulfuric acid. This natural weathering process is proposed as an analog to anthropogenic low pH rock weathering resulting from acid precipitation. In the Northeast, natural weathering rates, may, in places, significantly affect the water chemistry and mineralogy used to quantify total (natural plus anthropogenic) weathering and leaching rates. 27 references, 4 figures.

  13. New Space Weather and Nonlinear Waves and Processes Prize announced for 2013

    NASA Astrophysics Data System (ADS)

    Thompson, Victoria

    2012-01-01

    At the 2011 Fall Meeting in San Francisco, Calif., AGU announced the creation of a new award: the Space Weather and Nonlinear Waves and Processes Prize. The prize, which is being made possible by a generous contribution from longtime AGU members and NASA Jet Propulsion Laboratory (JPL), California Institute of Technology, scientists Bruce Tsurutani and Olga Verkhoglyadova, will recognize an AGU member scientist and will come with a $10,000 award. Tsurutani has served as a researcher with JPL since 1972 and is currently a senior research scientist. He was also the president of AGU's Space Physics and Aeronomy section from 1990 to 1992 and is a recipient of AGU's John Adam Fleming Medal, given for original research and technical leadership in geomagnetism, atmospheric electricity, aeronomy, space physics, and related sciences. Verkhoglyadova served as a professor of space physics in the Department of Astrophysics and Space Physics at Taras Shevchenko National University of Kyiv, in the Ukraine, prior to coming to the United States. Their leadership and dedication to AGU and to their field are apparent in their passion for this prize.

  14. Effect of Weathering Processes on Mineralogical and Mechanical Properties of Volcanic Rocks Used as Ballast Material for Railway Between Sabuncupinar and Kütahya in Western Turkey

    NASA Astrophysics Data System (ADS)

    Abiddin Erguler, Zeynal; Adıgüzel, Ömer; Derman, Mustafa

    2015-04-01

    Geomaterials used in engineering projects and man-made structures such as railway ballasts, buildings, historical structures, monuments and tombstones naturally weather as a result of various physico-chemical factors. Due to being long-term exposure to the anthroposphere, geomaterials used for these purposes provides important information to the researchers for understanding the effect of weathering processes on their time dependent physical, mineralogical and mechanical changes. Thus, researchers frequently can take advantage of available engineering time of man-made structures to assess weathering properties of the geomaterials used in their construction in terms of time dependent durability and stability of these structures. Considering the fact that railway ballasts produced from natural deposits of limestone, dolomite, granite, basalt etc., supply an important contribution for evaluation weathering processes, a research was carried out to determine the effect of weathering as a function of time on physical, mineralogical and mechanical properties of ballasts used for railway between Kütahya and Sabuncupınar in western Turkey. For this purpose, fresh and weathered rock samples exposed to physical and chemical weathering processes at different times were collected from quarry located in Sabuncupınar and nearby railway. This volcanic rock was previously classified as basalt based on the detailed mineralogical and geochemical analyses performed at the laboratories of the Mineral Research & Exploration General Directorate located in Ankara (Turkey). In-situ characteristics of sampling site were also investigated at different locations of quarry site by line surveying technique to describe the influence of discontinuity conditions on the weathering rate of selected rocks. Several techniques were utilized to determine time dependent deterioration in mineralogical and chemical composition of these samples for understanding their weathering rate. The porosity, water absorption by weight, weight loss after slake durability index and freezing-thawing tests and Los Angeles abrasion value of these samples subjected to weathering processes at different time intervals at field conditions were also determined to measure the time dependent resistance of collected ballast materials against natural weathering processes. When all results obtained from mineralogical and chemical analyses, field observations and further laboratory tests are considered, it can be concluded that collected ballast materials provide important information for understanding weathering rate of basalt. Furthermore, despite of being exposure to the anthroposphere for very long time, the very little water absorption content, resistance to extreme weather conditions and very angular characteristics of collected samples indicate that these previously used materials can still serve the purpose as ballast materials in accordance to related standards (TS 7043 and EN 13450).

  15. Gombosi Receives 2013 Space Weather and Nonlinear Waves and Processes Prize: Response

    NASA Astrophysics Data System (ADS)

    Gombosi, Tamas

    2014-08-01

    It is a great honor to be the recipient of AGU's inaugural Space Weather and Nonlinear Waves and Processes Prize. I am truly humbled by this recognition because there are many other highly deserving colleagues in our research field.

  16. The Colorado Student Space Weather Experiment : A CubeSat for Space Physics

    NASA Astrophysics Data System (ADS)

    Palo, Scott; Li, Xinlin; Gerhardt, David; Turner, Drew; Hoxie, V.; Kohnert, Rick; Batiste, Susan

    Energetic particles, electrons and protons either directly associated with solar flares or trapped in the terrestrial radiation belt, have a profound space weather impact. A National Science Foundation supported 3U CubeSat mission with a single instrument, Relativistic Electrons and Proton Telescope integrated little experiment (REPTile), is proposed to address fundamental scientific questions relating to these high energy particles. Of key importance are the relation-ship between solar flares and energetic particles and the acceleration and loss mechanism of outer radiation belt electrons. REPTile, operating in a highly inclined low earth orbit, will measure differential fluxes of relativistic electrons in the energy range of 0.5-3.5 MeV and pro-tons in 10-40 MeV. The Colorado Student Space Weather Experiment cubesat will be designed, integrated and testing by students at the University of Colorado under the oversight of pro-fessional engineers with the Laboratory of Atmospheric and Space Physics who have extensive space hardware experience. Our design philosophy is to use commercially off the shelf (COTS) parts where available and only engage in detailed designed where COTS parts cannot meet the system needs. The top level science requirements for the mission have driven the system and subsystem level performance requirements and the specific design choices such as a passive magnetic attitude system and instrument design. In this paper we will present details of the CSSWE design and management approach. Specifically we will discuss the top level science requirements for the mission and show that these measurements are novel and will address open questions in the scientific community. The overall system architecture resulting from a flow-down of these requirements will be presented with a focus on the novel aspects of the system including the instrument design. Finally we will discuss how this project is organized and man-aged as part of the Department of Aerospace Engineering graduate projects course sequence along with the integration of professional engineers in the program. It is often underappreciated that the management of a student project, given the transient nature of the students in the program, is more challenging than many of the technical aspects. We will discuss our process to managing this project risk along with our pedagological philosophy for student learning and its relationship to a small satellite program.

  17. Processing of Indian Doppler Weather Radar data for mesoscale applications

    NASA Astrophysics Data System (ADS)

    Roy Bhowmik, S. K.; Sen Roy, Soma; Srivastava, Kuldeep; Mukhopadhay, B.; Thampi, S. B.; Reddy, Y. K.; Singh, Hari; Venkateswarlu, S.; Adhikary, Sourav

    2011-03-01

    This paper demonstrates the usefulness of Indian Doppler Weather Radar (DWR) data for nowcasting applications, and assimilation into a mesoscale Numerical Weather Prediction (NWP) model. Warning Decision Support System Integrated Information (WDSS-II) developed by National Severe Storm Laboratory (NSSL) and Advanced Regional Prediction System (ARPS) developed at the Centre for Analysis and Prediction, University of Oklahoma are used for this purpose. The study reveals that the WDSS-II software is capable of detecting and removing anomalous propagation echoes from the Indian DWR data. The software can be used to track storm cells and mesocyclones through successive scans. Radar reflectivity mosaics are created for a land-falling tropical cycloneKhaimuk of 14 November 2008 over the Bay of Bengal using observations from three DWR stations, namely, Visakhapatnam, Machilipatnam and Chennai. Assimilation of the quality-controlled radar data (DWR, Chennai) of the WDSS-II software in a very high-resolution NWP model (ARPS) has a positive impact for improving mesoscale prediction. This has been demonstrated for a land-falling tropical cyclone Nisha of 27 November 2008 of Tamil Nadu coast. This paper also discusses the optimum scan strategy and networking considerations. This work illustrates an important step of transforming research to operation.

  18. Chemical Weathering of Soils from the Dry Valleys of Antarctica: a Terrestrial Analog of Martian Weathering Processes

    NASA Technical Reports Server (NTRS)

    Gibson, E. K., Jr.

    1985-01-01

    Martian soil subjected to chemical weathering processes could contain the following likely constituents: (1) fresh primary silicate material; (2) partially altered primary silicates; (3) secondary minerals, possibly including clay minerals, evaporites, carbonates, sulfates, hydrates, and zeolites; and (4) altered volcanic glass or impact glass. The soil may also include palogonite and other alteration products and secondary minerals. It is unlikely therefore that an equilibrium assemblage of minerals would be present. From the detailed study of the soils from the Dry Valleys of Antarctica, it is obvious that the complex processes in operation produce major changes in the parent materials, depending upon where the constituents reside and the degree to which weathering and diagenesis operates. It is clear that natural near surface environments, even in very cold and dry regions, may produce extremely complex soils. Extreme caution must be taken when interpreting the results and drawing conclusions, especially about possible processes operating in regoliths in cold, arid environments similar to those of the Dry Valleys or Mars.

  19. Physical Processing of Cometary Nuclei

    NASA Technical Reports Server (NTRS)

    Weissman, Paul R.; Stern, S. Alan

    1997-01-01

    Cometary nuclei preserve a cosmo-chemical record of conditions and processes in the primordial solar nebula, and possibly even the interstellar medium. However, that record is not perfectly preserved over the age of the solar system due to a variety of physical processes which act to modify cometary surfaces and interiors. Possible structural and/or internal processes include: collisional accretion, disruption, and reassembly during formation; internal heating by long and short-lived radionuclides; amorphous to crystalline phase transitions, and thermal stresses. Identified surface modification processes include: irradiation by galactic cosmic rays, solar protons, UV photons, and the Sun's T Tauri stage mass outflow; heating by passing stars and nearby supernovae; gardening by debris impacts; the accretion of interstellar dust and gas and accompanying erosion by hypervelocity dust impacts and sputtering; and solar heating with accompanying crust formation. These modification processes must be taken into account in both the planning and the interpretation of the results of a Comet Nucleus Sample Return Mission. Sampling of nuclei should be done at as great a depth below the surface crust as technically feasible, and at vents or fissures leading to exposed volatiles at depth. Samples of the expected cometary crust and near-surface layers also need to be returned for analysis to achieve a better understanding of the effects of these physical processes. We stress that comets are still likely less modified dm any other solar system bodies, but the degree of modification can vary greatly from one comet to the next.

  20. Modeling land-surface processes and land-atmosphere interactions in the community weather and regional climate WRF model (Invited)

    NASA Astrophysics Data System (ADS)

    Chen, F.; Barlage, M. J.

    2013-12-01

    The Weather Research and Forecasting (WRF) model has been widely used with high-resolution configuration in the weather and regional climate communities, and hence demands its land-surface models to treat not only fast-response processes, such as plant evapotranspiration that are important for numerical weather prediction but also slow-evolving processes such as snow hydrology and interactions between surface soil water and deep aquifer. Correctly representing urbanization, which has been traditionally ignored in coarse-resolution modeling, is critical for applying WRF to air quality and public health research. To meet these demands, numerous efforts have been undertaken to improve land-surface models (LSM) in WRF, including the recent implementation of the Noah-MP (Noah Multiple-Physics). Noah-MP uses multiple options for key sub-grid land-atmosphere interaction processes (Niu et al., 2011; Yang et al., 2011), and contains a separate vegetation canopy representing within- and under-canopy radiation and turbulent processes, a multilayer physically-based snow model, and a photosynthesis canopy resistance parameterization with a dynamic vegetation model. This paper will focus on the interactions between fast and slow land processes through: 1) a benchmarking of the Noah-MP performance, in comparison to five widely-used land-surface models, in simulating and diagnosing snow evolution for complex terrain forested regions, and 2) the effects of interactions between shallow and deep aquifers on regional weather and climate. Moreover, we will provide an overview of recent improvements of the integrated WRF-Urban modeling system, especially its hydrological enhancements that takes into account the effects of lawn irrigation, urban oasis, evaporation from pavements, anthropogenic moisture sources, and a green-roof parameterization.

  1. CHEMICAL WEATHERING AND SOLUTION CHEMISTRY IN ACID FOREST SOILS: DIFFERENTIAL INFLUENCE OF SOIL TYPE, BIOTIC PROCESSES, AND H+ DEPOSITION

    EPA Science Inventory

    In the investigation, weathering rates were calculated for three eastern North American forest soils using five separate estimation techniques. In addition, leaching experiments were performed to examine the influence of selected environmental variables on the weathering process....

  2. Conversion of bedrock to soil and feedback processes between the surface and the weathering front in a deeply weathered regolith, Central Sri Lankan Highlands

    NASA Astrophysics Data System (ADS)

    Behrens, Ricarda; Bouchez, Julien; Schuessler, Jan A.; Dultz, Stefan; Hewawasam, Tilak; von Blanckenburg, Friedhelm

    2014-05-01

    In the Sri Lankan highlands denudation rates and chemical weathering rates represent the low-end-member in global weathering rates [1, 2]. Here we explore the causes for these low rates by a detailed soil-mineralogical study of a highly weathered deep saprolite profile developed from charnockite bedrock. Spheroidal weathering of the bedrock characterized the weathering front where rounded corestones are produced at the rock-saprolite interface. The first mineral attacked by weathering was found to be pyroxene but plagioclase is the first mineral depleted to near-completion at the corestone-saprolite-boundary. Weathering of pyroxene is initiated by in situ iron oxidation, leading to an increase of porosity due to micro-cracking [3]. The accrued micro cracks allow for fluid transport and the dissolution of biotite and plagioclase. The strong plagioclase weathering leads to formation of high secondary porosity over a small distance and the final disaggregation of bedrock to saprolite. Sequential extraction showed that the first secondary phases are amorphous oxides from which secondary minerals (gibbsite, kaolinite, goethite and minor amounts of smectites) precipitate. Modeling of the strain formation due to increasing volume during iron oxidation in pyroxene and biotite showed that spheroidal weathering can be explained with this process only if the formation of secondary porosity, due to a negative volume budget during primary mineral weathering to secondary phases, occurs. As oxidation is the first occurring reaction, O2 is a rate limiting factor for chemical weathering in this setting. Hence the supply of oxygen and the consumption at depth connects processes at the weathering front with those at the surface as a feedback mechanism. Advective and diffusive transport modeling shows that the feedback will be much more pronounced with dominating diffusive transport. Due to the low porosity of the bedrock the O2 transport in the pristine bedrock occurs via diffusion. The slow weathering rate is, beside tectonic quiescence, related to this feedback and to lithological factors such as low porosity and the amount of Fe-bearing primary minerals. 1. Hewawasam, T., et al., Slow advance of the weathering front during deep, supply-limited saprolite formation in the tropical Highlands of Sri Lanka. Geochimica et Cosmochimica Acta, 2013. 118: p. 202-230. 2. von Blanckenburg, F., T. Hewawasam, and P. Kubik, Cosmogenic nuclide evidence for low weathering and denudation in the wet tropical Highlands of Sri Lanka. J. Geoph. Res., 2004. 109: p. doi10.1029/2003JF000049. 3. Buss, H.L., et al., Weathering of the Rio Blanco quartz diorite, Luquillo Mountains, Puerto Rico: Coupling oxidation, dissolution, and fracturing. Geochimica et Cosmochimica Acta, 2008. 72(18): p. 4488-4507.

  3. a 100% Renewable Power System for Europe -- let the Weather and Physics DECIDE!

    NASA Astrophysics Data System (ADS)

    Greiner, Martin; Heide, Dominik; Rasmussen, Morten; Andresen, Gorm

    2012-01-01

    The design of sustainable energy systems is no longer only the domain of politics, economics and engineering. Mathematical physics is able to contribute with its generic understanding of everything. A new modelling approach is presented and applied to design a fully renewable European power system. This approach is based on weather data with good spatio-temporal resolution, which is first converted into wind and solar power generation and then used to derive estimates on the optimal mix between the renewable resources and the storage needs.

  4. TIMBER HARVESTING AND LONG-TERM PRODUCTIVITY: WEATHERING PROCESSES AND SOIL DISTURBANCE

    EPA Science Inventory

    Both timber harvesting and amelioration practices can cause chemical and physical changes in soil. hese changes can affect factors which alter soil mineral stability and weathering rates, potentially changing inputs to the nutrient cycle. his paper discusses possible effects of h...

  5. Formation of Silica Deposits on Mars by Acid Weathering: Physical-Chemical Constraints

    NASA Astrophysics Data System (ADS)

    McAdam, A. C.; Zolotov, M. Y.; Mironenko, M. V.; Sharp, T. G.

    2007-12-01

    Many chemical and mineralogical characteristics of martian surface materials are indicative of exposure to acidic solutions. Silica-rich outcrops and soils found in Gusev crater could also result from acid weathering. We used thermochemical equilibrium and coupled kinetic-thermodynamic models to investigate conditions under which abundant amorphous silica forms by low-temperature (273 K) H2SO4-HCl acid weathering of mafic/ultramafic rocks. We explored the effects of pH, solution/rock ratio (W/R) and rock composition on secondary mineralogy, solution chemistry, and timing of weathering. Modeling shows that silica-rich deposits form mainly under very acid conditions (pHs<~2-3) and at high W/R ratios (~102-103). High W/R ratios may represent solution discharge in spring environments, groundwater flow, or lake settings. If solution pH does not change much during high W/R alteration, silica-rich (>90 vol% silica) mineral assemblages form at pHs<~2. If acid solutions with original pH<~2 are neutralized as weathering proceeds, abundant silica precipitates at early stages of weathering (W/Rs >~102) below pH ~3. Calculated timing of silica deposition is consistent with these inferences. Kinetic models also demonstrate that silica can dissolve when the solution neutralizes. Silica precipitation conditions are similar for several potential martian protoliths, however, the volume precipitated increases with increasing rock SiO2 content (Shergotty basalt > Adirondack olivine basalt > Chassigny dunite). Low-pH deposition of amorphous silica is consistent with experimental Mars analog studies and theoretical models directed at understanding martian acid weathering. Observed Ti enrichment in some of the high silica deposits in Gusev crater is also consistent with a low-pH process. Rapid dissolution of mafic minerals and glass in cold, low-pH fluids could have been followed by the precipitation of silica and Ti-oxide owing to their low and comparable solubilities in these solutions. However, a high-temperature (e.g., hydrothermal) origin for the observed deposits remains a possibility.

  6. The Spatial Variability of Weathering Processes in a Peruvian River System

    NASA Astrophysics Data System (ADS)

    Torres, M. A.; Ballew, N.; Clark, K.; West, A.

    2011-12-01

    The role of floodplains in the weathering of sediment exported from mountainous regions is poorly understood and has the potential to play a significant role in the overall weathering budget of large river systems. While high rates of floodplain weathering have been measured in the Himalayan system [1], there are conflicting results concerning the importance of floodplain weathering in the Amazon system [2-3]. To address this issue, the dissolved major element chemistry of the Kosipata-Madre de Dios river system in Peru was measured monthly in nested catchments spanning the headwater-floodplain transition in order to determine spatially-resolved weathering rates and to examine any associated changes in weathering processes. Analysis of the dissolved major element data reveals a change in the dominant weathering process controlling the Ca2+ and Mg2+ fluxes associated with the headwater-floodplain transition. Based on (Ca2+ + Mg2+) / HCO3- ratios near 0.5, Ca2+ and Mg2+ fluxes in the floodplain are controlled by carbonate dissolution by carbonic acid. In the Andean catchments, variable (Ca2+ + Mg2+) / HCO3- ratios, (Ca2+ + Mg2+) / SO42- ratios near 1, and high SO42- concentrations suggest that either carbonate dissolution by sulfuric acid or sulfate mineral dissolution is the main control on Ca2+ and Mg2+ fluxes. This observed change is significant as it has important implications for the net consumption of CO2 by silicate weathering in this river system. [1] West, AJ et al, 2002, Geology 30: 355-358, [2] Gaillardet, J et al, 2006, Geochim. Cosmochim. Acta 70: 189, [3] Moquet, J et al, 2011, Chem. Geol 287: 1-26

  7. Geochemistry of river-borne clays entering the East China Sea indicates two contrasting types of weathering and sediment transport processes

    NASA Astrophysics Data System (ADS)

    Bi, Lei; Yang, Shouye; Li, Chao; Guo, Yulong; Wang, Quan; Liu, James T.; Yin, Ping

    2015-09-01

    The East China Sea is characterized by wide continental shelf receiving a huge input of terrigenous matter from both large rivers and mountainous rivers, which makes it an ideal natural laboratory for studying sediment source-to-sink transport processes. This paper presents mineralogical and geochemical data of the clays and bulk sediments from the rivers entering the East China Sea, aiming to investigate the general driving mechanism of silicate weathering and sediment transport processes in East Asian continental margin. Two types of river systems, tectonically stable continental rivers and tectonically active mountainous rivers, coexist in East Asia. As the direct weathering products, clays can better reflect the silicate weathering regimes within the two river systems. Provenance rock types are not the dominant factor causing silicate weathering intensity difference existed in the East Asian rivers. The silicate weathering intensity of tectonically stable river basins is primarily driven by monsoon climate, and the sediment transfer is relatively slow because of natural trapping process and increasing damming effect. The geochemistry of these river-borne sediments can thus indicate paleo-weathering intensities in East Asian continent. In contrast, silicate weathering intensity in tectonically active mountainous rivers is greatly limited by strong physical erosion despite the high temperature and highest monsoon rainfall. The factors controlling silicate weathering in tectonically active catchments are complex and thus, it should be prudent to use river sediment records to decipher paleoclimate change. These two different silicate weathering regimes and sediment transport processes are manifestations of the landscape evolution and overall dominate the sedimentation in Asian continental margin.

  8. Two-dimensional gas chromatography/mass spectrometry, physical property modeling and automated production of component maps to assess the weathering of pollutants.

    PubMed

    Antle, Patrick M; Zeigler, Christian D; Livitz, Dimitri G; Robbat, Albert

    2014-10-17

    Local conditions influence how pollutants will weather in subsurface environments and sediment, and many of the processes that comprise environmental weathering are dependent upon these substances' physical and chemical properties. For example, the effects of dissolution, evaporation, and organic phase partitioning can be related to the aqueous solubility (SW), vapor pressure (VP), and octanol-water partition coefficient (KOW), respectively. This study outlines a novel approach for estimating these physical properties from comprehensive two-dimensional gas chromatography-mass spectrometry (GCGC/MS) retention index-based polyparameter linear free energy relationships (LFERs). Key to robust correlation between GC measurements and physical properties is the accurate and precise generation of retention indices. Our model, which employs isovolatility curves to calculate retention indices, provides improved retention measurement accuracy for families of homologous compounds and leads to better estimates of their physical properties. Results indicate that the physical property estimates produced from this approach have the same error on a logarithmic-linear scale as previous researchers' log-log estimates, yielding a markedly improved model. The model was embedded into a new software program, allowing for automated determination of these properties from a single GCGC analysis with minimal model training and parameter input. This process produces component maps that can be used to discern the mechanism and progression of how a particular site weathers due to dissolution, organic phase partitioning, and evaporation into the surrounding environment. PMID:25223613

  9. Chemical weathering processes in the Great Artesian Basin: Evidence from lithium and silicon isotopes

    NASA Astrophysics Data System (ADS)

    Pogge von Strandmann, Philip A. E.; Porcelli, Don; James, Rachael H.; van Calsteren, Peter; Schaefer, Bruce; Cartwright, Ian; Reynolds, Ben C.; Burton, Kevin W.

    2014-11-01

    Variations in lithium and silicon isotope ratios in groundwaters of the Great Artesian Basin in Australia, and the causes of these variations, have been explored. The chemistries of Li and Si in groundwater are influenced by the dissolution of primary phases, the formation of secondary minerals, and the reaction of solid phases with dissolved constituents, while isotopic variations are generated by uptake into clays, which preferentially incorporate the light isotopes. The lithium isotopic composition (expressed as ? 7Li) of the groundwaters ranges from +9 to +16 , and clearly reflects changes in aquifer conditions. Reaction-transport modelling indicates that changes in Li concentrations are principally controlled by the ratio of the weathering rate of primary minerals to the precipitation rate of secondary minerals, whereas ? 7Li is affected by the extent of isotope fractionation during secondary mineral formation (which is dependent on mineralogy). The patterns of groundwater Si concentrations and ? 30Si values versus flow distance suggest that Si is at steady state in the aquifer. The ? 30Si value of most of the groundwater samples is close to -1 , which is significantly lower than the ? 30Si value of the reservoir rocks (?0 ). Since precipitation of clays preferentially removes the light Si isotopes from solution, the most plausible explanation for these low groundwater ? 30Si values is addition of Si by dissolution of isotopically light secondary minerals. These data, together with model calculations, show that Li isotopes are extremely sensitive to changes in the chemical and physical conditions in the aquifer, whereas Si is not. Importantly, the model suggests that even in large aquifers with long fluid residence times, where steady-state would be expected to be reached, the concentrations and isotopic fractionation of trace elements are not controlled by Li adsorption. The model developed here provides a basis for using Li isotopes measured in groundwaters and surface waters to constrain weathering processes.

  10. Space Weather data processing and Science Gateway for the Van Allen Probes

    NASA Astrophysics Data System (ADS)

    Romeo, G.; Barnes, R. J.; Weiss, M.; Fox, N. J.; Mauk, B.; Potter, M.; Kessel, R.

    2013-12-01

    A near real-time data processing pipeline for the Space Weather broadcast data from the Van Allen Probes is presented. The Van Allen Probes broadcasts a sub-set of the science data in real-time when not downlinking the principal science data. This broadcast is received by several ground stations and relayed to APL in near real time to be ingested into the space weather processing pipeline. This pipeline processes the available level zero space weather data into higher level science data products. These products are made available to the public via the Van Allen Probes Science Gateway website (http://athena.jhuapl.edu). The website acts as pivotal point though which all other instrument SOC's can be accessed. Several other data products (e.g KP/DST indices) and tools (e.g orbit calculator) are made also available to the general public.

  11. Using weather prediction data for simulation of mesoscale atmospheric processes

    NASA Astrophysics Data System (ADS)

    Bart, Andrey A.; Starchenko, Alexander V.

    2015-11-01

    The paper presents an approach to specify initial and boundary conditions from the output data of global model SLAV for mesoscale modelling of atmospheric processes in areas not covered by meteorological observations. From the data and the model equations for a homogeneous atmospheric boundary layer the meteorological and turbulent characteristics of the atmospheric boundary layer are calculated.

  12. Investigation of changes in surface properties of bituminous coal during natural weathering processes by XPS and SEM

    NASA Astrophysics Data System (ADS)

    Xia, Wencheng; Yang, Jianguo; Liang, Chuan

    2014-02-01

    In this investigation, XPS and SEM were used to indicate the changes in surface properties of bituminous coal during natural weathering processes. Natural weathering processes of bituminous coal were conducted on the roof. XPS results showed that the content of CC and CH groups on bituminous coal surface decreased but the content of CO, CO, and OCO groups increased after natural weathering processes. Meanwhile, the contents of Al and Si elements on bituminous coal surface were also increased. SEM results showed that the surface roughness of bituminous coal was increased after natural weathering processes. Natural weathering processes not only changed surface chemical composition of bituminous coal but also changed surface topography of bituminous coal. In addition, natural weathering processes made bituminous coal surface more hydrophilic.

  13. Mapping Glacial Weathering Processes with Thermal Infrared Remote Sensing: A Case Study at Robertson Glacier, Canada

    NASA Astrophysics Data System (ADS)

    Rutledge, A. M.; Christensen, P. R.; Shock, E.; Canovas, P. A., III

    2014-12-01

    Geologic weathering processes in cold environments, especially subglacial chemical processes acting on rock and sediment, are not well characterized due to the difficulty of accessing these environments. Glacial weathering of geologic materials contributes to the solute flux in meltwater and provides a potential source of energy to chemotrophic microbes, and is thus an important component to understand. In this study, we use Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data to map the extent of glacial weathering in the front range of the Canadian Rockies using remotely detected infrared spectra. We ground-truth our observations using laboratory infrared spectroscopy, x-ray diffraction, and geochemical analyses of field samples. The major goals of the project are to quantify weathering inputs to the glacial energy budget, and to link in situ sampling with remote sensing capabilities. Robertson Glacier, Alberta, Canada is an excellent field site for this technique as it is easily accessible and its retreating stage allows sampling of fresh subglacial and englacial sediments. Infrared imagery of the region was collected with the ASTER satellite instrument. At that same time, samples of glacially altered rock and sediments were collected on a downstream transect of the glacier and outwash plain. Infrared laboratory spectroscopy and x-ray diffraction were used to determine the composition and abundance of minerals present. Geochemical data were also collected at each location, and ice and water samples were analyzed for major and minor elements. Our initial conclusion is that the majority of the weathering seems to be occurring at the glacier-rock interface rather than in the outwash stream. Results from both laboratory and ASTER data indicate the presence of leached weathering rinds. A general trend of decreasing carbonate abundances with elevation (i.e. residence time in ice) is observed, which is consistent with increasing calcium ion meltwater concentrations towards the glacier terminus. These results are used to map the extent of regional glacial chemical weathering using ASTER thermal imagery.

  14. [Role of microscopic fungi in the process of weathering of pegmatite deposit rocks and minerals].

    PubMed

    Avakian, Z A; Karavaiko, G I; Mel'nikova, E O; Krutsko, V S; Ostroushko, Iu I

    1981-01-01

    The object of this work was to study the effect of microscopic fungi isolated from the weathering zone of a pegmatite deposit on the transport of elements and the degradation of rocks and minerals. Regardless of the chemical composition of rocks and minerals, microscopic fungi accelerated the leaching of elements as compared to the purely chemical process. The extraction of Li, Si, Al and Fe under the action of microorganisms increased by factors of 1.4-1.7, 2.7-4.0, 5.0-8.7 and 4-18, respectively. In the case of chemical weathering, the extraction of elements occurred at a high rate only at the beginning; then the process either decelerated or stopped. The mechanism of action of microscopic fungi on rocks and minerals is discussed as well as the role of these microorganisms in the weathering of spodumene and the surrounding rocks, pegmatites an shales, which occurs in the zone of hypergenesis. PMID:7194415

  15. RBSP Space Weather data

    NASA Astrophysics Data System (ADS)

    Weiss, M.; Fox, N. J.; Mauk, B. H.; Barnes, R. J.; Potter, M.; Romeo, G.; Smith, D.

    2012-12-01

    On August 23, 2012, NASA will launch two identical probes into the radiation belts to provide unprecedented insight into the physical processes and dynamics of near-Earth space. The RBSP mission in addition to the scientific data return, provides a 1Kbps real-time space weather broadcast data in support of real time space weather modeling, forecast and prediction efforts. Networks of ground stations have been identified to downlink the space weather data. The RBSP instrument suites have selected space weather data to be broadcast from their collected space data on board the spacecraft, a subset from measurements based on information normally available to the instrument. The data subset includes particle fluxes at a variety of energies, and magnetic and electric field data. This selected space weather data is broadcast at all times through the primary spacecraft science downlink antennas when an observatory is not in a primary mission-related ground contact. The collected data will resolve important scientific issues and help researchers develop and improve various models for the radiation belts that can be used by forecasters to predict space weather phenomena and alert astronauts and spacecraft operators to potential hazards. The near real-time data from RBSP will be available to monitor and analyze current environmental conditions, forecast natural environmental changes and support anomaly resolution. The space weather data will be available on the RBSP Science Gateway at http://athena.jhuapl.edu/ and will provide access to the space weather data received from the RBSP real-time space weather broadcast. The near real-time data will be calibrated and displayed on the web as soon as possible. The CCMC will ingest the RBSP space weather data into real-time models. The raw space weather data will be permanently archived at APL. This presentation will provide a first look at RBSP space weather data products.

  16. Effects Of Fungal-Mineral Interactions On Chemical Weathering And Denudation Processes - Observations From Experimental Ecosystems

    NASA Astrophysics Data System (ADS)

    Balogh, Z.; Keller, C.; Dickinson, J.

    2003-12-01

    A mesoscale (`sandbox') lysimeter experiment was performed at Hubbard Brook Experimental Forest, New Hampshire, to study plant-growth influences on chemical weathering and chemical denudation. Weathering was estimated by mass balance for 5 and 15-year intervals, and denudation was monitored as the product of drainage flow and concentration for 20 years in large (7.5x7.5x1.5m) fully lined sandboxes a.) planted with red pine (Pinus resinosa Ait.), and b.) kept free of vascular vegetation. Mass-balance equations included base cations (Ca, Mg, and K) in precipitation inputs and drainage outputs, and changes of base cation contents in biomass and soil. Scanning Electron Microscopy (SEM) and Environmental-SEM studies of the coarse sandbox soils were used for detection of mycorrhizal fungal association with roots, fungal development and attachment features on mineral grain surfaces. In the non-vascular system chemical weathering and denudation fluxes did not change significantly during the monitored period, but denudation fluxes were 1.3-1.4 times higher than weathering fluxes. In the vascular ecosystem the chemical weathering flux was 3 and 1.8 times greater than the denudation flux over 5 and 15 years, respectively, but both rates decreased over time. In our experiment the pines retarded denudation and accelerated weathering relative to the nonvascular system, thereby increasing available nutrient pools. The SEM and ESEM studies indicated more weathering features (etch pits, cracks, wholes, channels, and secondary minerals) in the mineral surfaces of the vascular system associated with the mycorrhizal fungal hyphae. Profiles of base-cation concentrations in soil water suggest that hyphal-mineral surface attachment might also insulate cation uptake from bulk soil water and hydrologic loss. The sandbox study offers insight into short-term effects of ecosystems on global biogeochemical processes.

  17. Mismatched Physical and Chemical Weathering of Rocks on Mars: Clues to Past Climate

    NASA Astrophysics Data System (ADS)

    Thomson, B. J.; Hurowitz, J. A.; Baker, L. L.; Bridges, N. T.; Lennon, A.; Paulson, G.; Zacny, K.

    2014-07-01

    Here we quantify the degree of weathering experienced by the Adirondack-class basalts at the MER Spirit site by performing comparative analyses on the strength and chemistry of a series of progressively weathered Columbia River Basalt samples.

  18. The Relationships between Weather-Related Factors and Daily Outdoor Physical Activity Counts on an Urban Greenway

    PubMed Central

    Wolff, Dana; Fitzhugh, Eugene C.

    2011-01-01

    The purpose of this study was to examine relationships between weather and outdoor physical activity (PA). An online weather source was used to obtain daily max temperature [DMT], precipitation, and wind speed. An infra-red trail counter provided data on daily trail use along a greenway, over a 2-year period. Multiple regression analysis was used to examine associations between PA and weather, while controlling for day of the week and month of the year. The overall regression model explained 77.0% of the variance in daily PA (p < 0.001). DMT (b = 10.5), max temp-squared (b = ?4.0), precipitation (b = ?70.0), and max wind speed (b = 1.9) contributed significantly. Conclusion: Aggregated daily data can detect relationships between weather and outdoor PA. PMID:21556205

  19. Shenandoah National Park Phenology Project-Weather data collection, description, and processing

    USGS Publications Warehouse

    Jones, John W.; Aiello, Danielle P.; Osborne, Jesse D.

    2010-01-01

    The weather data described in this document are being collected as part of a U.S. Geological Survey (USGS) study of changes in Shenandoah National Park (SNP) landscape phenology (Jones and Osbourne, 2008). Phenology is the study of the timing of biological events, such as annual plant flowering and seasonal bird migration. These events are partially driven by changes in temperature and precipitation; therefore, phenology studies how these events may reflect changes in climate. Landscape phenology is the study of changes in biological events over broad areas and assemblages of vegetation. To study climate-change relations over broad areas (at landscape scale), the timing and amount of annual tree leaf emergence, maximum foliage, and leaf fall for forested areas are of interest. To better link vegetation changes with climate, weather data are necessary. This report documents weather-station data collection and processing procedures used in the Shenandoah National Park Phenology Project.

  20. Chemical and Physical Weathering in a Hot-arid, Tectonically Active Alluvial System (Anza-Borrego Desert, CA)

    NASA Astrophysics Data System (ADS)

    Joo, Y. J.; Elwood Madden, M.; Soreghan, G. S.

    2014-12-01

    Climate and tectonics are primary controls on bedrock erosion, and sediment production, transport, and deposition. Additionally, silicate weathering in tectonically active regions is known to play a significant role in global climate owing to the high rates of physical erosion and exposure of unweathered bedrock to chemical weathering, which removes CO2 from the atmosphere. Therefore, the feedback between weathering and climate is key to understanding climate change through Earth history. This study investigates chemical and physical weathering of alluvial sediments in the Anza-Borrego Desert, California, located in the southern part of the San Andreas Fault System. This setting provides an ideal opportunity to study weathering in a hot and arid climate with mean annual temperatures of ~23 °C and mean annual precipitation of ~160 mm in the basin. Samples were collected along a proximal-to-distal transect of an alluvial-fan system sourced exclusively from Cretaceous tonalite of the Peninsular Range. The single bedrock lithology enables exploration of the effects of other variables — climate, transport distance, drainage area, and tectonics— on the physical and chemical properties of the sediments. Although minimal overall (CIA = 56-61), the degree of chemical weathering increases down transect, dominated by plagioclase dissolution. BET surface area of the mud (<63µm) fraction decreases distally, which is consistent with coarsening grain-size. Chemical alteration and BET surface area both increase in a distal region, within the active Elsinore Fault zone. Extensive fracturing here, together with a more-humid Pleistocene climate likely facilitated in-situ bedrock weathering; specifically, dissolution of primary minerals (e.g. plagioclase), preceding the arid alluvial erosion, transport, and deposition in the Holocene. This study further seeks to disentangle the complex record of the climate and tectonic signals imprinted in these sediments.

  1. Physical Fitness and the Stress Process

    ERIC Educational Resources Information Center

    Ensel, Walter M.; Lin, Nan

    2004-01-01

    In the current paper we focus on the role of physical fitness in the life stress process for both psychological and physical well-being. The major research question posed in the current study is: Does physical fitness deter distress in a model containing the major components of the life stress process? That is, do individuals who exercise show…

  2. Space-weathering processes and products on volatile-rich asteroids

    NASA Astrophysics Data System (ADS)

    Britt, D.; Schelling, P.; Consolmagno, G.; Bradley, T.

    2014-07-01

    Space weathering is a generic term for the effects on atmosphereless solid bodies in the solar system from a range of processes associated with direct exposure to the space environment. These include impact processes (shock, vaporization, fragmentation, heating, melting, and ejecta formation), radiation damage (from galactic and solar cosmic rays), solar-wind effects (irradiation, ion implantation, and sputtering), and the chemical reactions driven by these processes. The classic example of space weathering is the formation of the lunar spectral red slope associated with the production of nanophase Fe (npFe0) in the dusty lunar regolith (C.R. Chapman, 2004, Annual Review of Earth & Planet. Sci. 32, C.M. Pieters, 2000, MAPS 35). Similar npFe0 has been recovered from asteroid (25143) Itokawa and some asteroid classes do exhibit modest spectral red slopes (T. Noguchi, 2011, Science 333). Space weathering can be thought of as driven by a combination of the chemical environment of space (hard vacuum, low oxygen fugacity, solar-wind implantation of hydrogen) along with thermal energy supplied by micrometeorite impacts. The forward modeling of space weathering as thermodynamically-driven decomposition of common rock-forming minerals suggests the production of a range of daughter products: (1) The silicate products typically lose oxygen, other volatile elements (i.e., sulfur and sodium), and metallic cations, producing minerals that are typically more disordered and less optically active than the original parent materials. (2) The decomposed metallic cations form in nano-sized blebs including npFe0, on the surfaces or in condensing rims of mineral grains. This creates a powerful optical component as seen in the lunar red slope. Surfaces with exposed npFe0 are an ideal environment for catalyzing further reactions. (3) The liberated volatile elements and gases (O, S, Na) may form an observable exosphere (e.g., Moon and Mercury) and can either escape from the body or recombine with available solar-wind-implanted hydrogen to form trace amounts of water and OH. Mineral decomposition can be thought of as the first stage of space weathering. It produces weathered surfaces somewhat depleted in volatile elements, creates a predictable set of minor or trace minerals, and leaves the surfaces with catalytic species, primarily npFe0. However, a second stage of further reactions and weathering depends upon the presence of ''feed-stock'' components that can participate in catalyzed chemical reactions on exposed surfaces. For volatile-rich small bodies, the available materials are not only silicates, but a volatile feedstock that can include water, carbon monoxide, ammonia, to name a few. Thermodynamically-driven decomposition of silicates will produce trace amounts of npFe0 which are ideal sites for Fischer-Tropsch type (FTT) catalytic reactions that can produce organics in situ on the asteroids including alkanes, polyaromatic hydrocarbons, and amino acids (J.E. Elsila, 2012, MAPS 47). The mix and range of products depends on the composition and morphology of the mineral surface, energy inputs produced by the micrometeorite impacts or other processes, and the composition of the input volatile feedstock. FFT reactions generate long-chain carbon compounds and amino acids. Secondary reactions that generate more complex carbon compounds and amino acids are likely to occur as the organic material matures. Weathering maturity can be thought of as a function of the abundance and diversity of the weathering products. Since the npFe0 is not destroyed in the reaction, continued micrometeorite bombardment would result in continuing processing and recombination of the existing organic feedstock. More weathering would result in progressively longer-chain carbon compounds as well as more complex and diverse amino acids, and eventually the kerogen-like insoluble-organic matter that forms a large fraction of carbonaceous meteorites. This insight has several major implications for our planetary science and, potentially, the formation of the precursors of life. First, the range of weathering products seen in remotely-sensed data, meteorites, and returned samples are not random, but the predictable outcome of the source region's mineral kinetics and chemical feedstock. Weathering products do not have to be optically active like the npFe0 that produces the lunar red slope; on the contrary, probably most weathering products are spectrally neutral or even suppress an object's near-IR reflectance spectrum. In the case of volatile-rich parent bodies, a major weathering product is a range of carbon-rich compounds. But an additional result of considerable interest is the generation of pre-biotic compounds as a routine and predictable byproduct of common space-weathering processes. Any atmosphereless body around any star with mafic silicate mineral compositions and volatile feedstocks should create amino acids as a standard byproduct of space weathering. The precursors of life are probably abundant in any space-weathered asteroid belt, in any solar system, and only wait being accreted to a hospitable environment.

  3. Paleopedological reconstruction and quantitative analysis of weathering processes in the Southern Piedmont Province

    SciTech Connect

    Feldman, S.B.; Zelazny, L.W. ); Pavich, M.J. )

    1992-01-01

    Soils and paleosols are commonly used to estimate ages of deposits and geomorphic surfaces, and to infer paleoenvironmental conditions during pedogenesis. Accurate interpretation of these and other parameters is currently limited, however, by considerable uncertainty in many fundamental areas of soils-geomorphic research. These include: (1) lack of accurate estimates of weathering rates for reliably-dated surfaces, (2) inability to quantitatively differentiate between the complex effects of climate vs. geomorphic age on weathering rates, processes, and pedogenic properties, and (3) difficulty in assessing which soil properties persist, alter, or become obliterated in the weathering environment as conditions change. In this paper, the authors discuss a method for assessing, on a regional basis, the quantitative relationships between climate, time, and weathering processes along a soil climosequence in the Southern Piedmont Province. Their approach involves sampling exclusively in areas of granitic plutons that exhibit a high degree of homogeneity with regard to total Fe content, bulk mineralogy, and absence of secondary phyllosilicates or sesquioxides. Independent age control is being established by [sup 10]Be dating, and analytical techniques include, in part, (1) geochemical speciation of soil solution and mineral equilibrium determination, (2) elemental analysis and mass balance calculations of elemental flux during pedogenesis, and (3) detailed analysis of Fe-oxide crystallinity, structure, and Al substitution using selective dissolution analysis, and both X-ray and differential X-ray diffraction.

  4. Deducing Weathering Processes Using Silicon Isotopes in the Ganges Alluvial Plain, India

    NASA Astrophysics Data System (ADS)

    Frings, P.; De La Rocha, C. L.; Fontorbe, G.; Chakrapani, G.; Clymans, W.; Conley, D. J.

    2014-12-01

    The Ganges Alluvial Plain ('GAP') is the sedimentary infill of the foreland basin created during Himalayan orogeny. Freshly eroded material from the Himalaya and southern cratonic tributaries is deposited into a system with long water-sediment interaction times, creating potential for further generation of river weathering fluxes. To quantify weathering processes in the GAP, 51 sites including all major tributaries were sampled in a September 2013 campaign and analysed for major and minor ions, Ge/Si ratios and ?30Si, ?13C and ?18O. Net dissolved Si (DSi) and major cation yields are 2 to 5 times lower in the GAP than the Himalaya, and at a whole basin scale approximate the global average, indicating that the plain apparently moderates the efficiency of Himalayan weathering rates. Mainstem ?30Si spans 0.81 to 1.93 (see figure) and gives the impression of a system buffered to moderate DSi and ?30Si. Ge/Si ratios (mol/mol) are higher than expected in the Himalaya (>3), reflecting input of Ge-enriched water from hot springs, and decline to ~1.4 in the GAP. For the Himalayan sourced rivers, ?30Si increases with distance from the Himalayan front, and can not be explained entirely by conservative mixing with higher ?30Si peninsular and GAP streams. To a first degree, the ?30Si data suggest incorporation of Si into secondary minerals as the key fractionating process, and that this occurs both in situ during initial weathering and progressively in the GAP. Partitioning of solutes between sources is complicated in the GAP. Consistent with previous work, carbonate weathering dominates the ion fluxes, but with substantial contributions from saline/alkaline soil salts, the chlorination of wastewater and highly variable rainfall chemistry. Due to these contributions, precisely inferring the input from silicate weathering is difficult. We introduce a novel method to infer silicate-weathering rates that exploits the fractionation of Si during clay formation to account for the loss of DSi from solution.

  5. Inclusions in precious Australian opals offer a unique access to Martian-like weathering processes

    NASA Astrophysics Data System (ADS)

    Roberts, Gemma; Rey, Patrice; Carter, Elizabeth

    2015-04-01

    Spectral signatures of the surface of Mars indicate a variety of hydrated minerals, including Al- and Fe/Mg-rich phyllosilicates, iron oxides, sulfates, and opaline silica. Their formation has been attributed to a long-lived low-temperature aqueous weathering history (e.g. Bishop et al., 2008; Ehlmann et al., 2013) followed by a period of intense acidic oxidative weathering (e.g. Carter et al., 2013). Very acidic weathering, driven by volcanic-derived sulfuric acid, is possible on a regional scale on Mars because of the lack of carbonate. On Earth, however, low-pH weathering on a regional scale is unusual because of the abundance of carbonate. Finding regional-scale Martian analogues on Earth is therefore a challenge. The Great Artesian Basin (GAB) in central Australia formed during the Early Cretaceous from the deposition of pyrite-rich volcaniclastic sediments in a cold, muddy, anoxic and shallow continental sea. Following mid-Cretaceous sea regression, a deep (~100 m) weathering profile recorded a protracted episode (~from 97 to 60 Ma) of oxidative weathering during continuous uplift and denudation, which stopped 60 myr ago. Since then, the weathering profile, which consists of Al- and Fe-rich phyllosilicates, iron oxides, and sulfates, has been constantly reworked. Interestingly, this profile hosts the bulk of the world's precious opal deposits. Since no opal deposit can be found in post-60 Ma rock formations, it is most likely that opal is part of the weathering profile developed during the drying out of central Australia. We analysed the mineral inclusions from six opal samples from the GAB to better document the early oxidative weathering. Using VNIR and Raman spectroscopy we were able to identify a variety of minerals including ferrihydrite, barite, gypsum and alunite replaced by goethite. This mineralogical assemblage is indicative of acidic oxidative conditions that points to Martian-like acidic weathering. We propose that acidity was derived from the oxidation of biogenic pyrite, and that the quasi absence of carbonates allowed very acidic conditions to take hold at a regional scale. If this model is valid, central Australia may be one of the best terrestrial analogues for the understanding of some of Mars' weathering processes. References Bishop, J.L., Noe Dobrea, E.Z., McKeown, N.K., Parente, M., Ehlmann, B.L., Michalski, J.R., Milliken, R.E., Poulet, F., Swayze, G.A., Mustard, J.F., Murchie, S.L. and Bibring, J.-P. (2008): Phyllosilicate Diversity and Past Aqueous Activity Revealed at Mawrth Vallis, Mars, Science 321(5890), 830-833. Carter, J., Poulet, F., Bibring, J.-P., Mangold, N., Murchie, S. (2013): Hydrous minerals of Mars as seen by the CRISM and OMEGA imaging spectrometer: Updated global view, Journal of Geophysical Research: Planets 118, 831-858. Ehlmann, B. L., Berger, G., Mangold, N., Michalski, J. R., Catling, D. C., Ruff, S. W., Chassefière, E., Niles, P. B., Chevrier, V., Poulet, F. (2013): Geochemical Consequences of Widespread Clay Minerals Formation in Mars' Ancient Crust, Space Science Review 174, 329-364.

  6. Composing Models of Geographic Physical Processes

    NASA Astrophysics Data System (ADS)

    Hofer, Barbara; Frank, Andrew U.

    Processes are central for geographic information science; yet geographic information systems (GIS) lack capabilities to represent process related information. A prerequisite to including processes in GIS software is a general method to describe geographic processes independently of application disciplines. This paper presents such a method, namely a process description language. The vocabulary of the process description language is derived formally from mathematical models. Physical processes in geography can be described in two equivalent languages: partial differential equations or partial difference equations, where the latter can be shown graphically and used as a method for application specialists to enter their process models. The vocabulary of the process description language comprises components for describing the general behavior of prototypical geographic physical processes. These process components can be composed by basic models of geographic physical processes, which is shown by means of an example.

  7. Anvil Forecast Tool in the Advanced Weather Interactive Processing System (AWIPS)

    NASA Technical Reports Server (NTRS)

    Barrett, Joe H., III; Hood, Doris

    2009-01-01

    Launch Weather Officers (LWOs) from the 45th Weather Squadron (45 WS) and forecasters from the National Weather Service (NWS) Spaceflight Meteorology Group (SMG) have identified anvil forecasting as one of their most challenging tasks when predicting the probability of violating the Lightning Launch Commit Criteria (LLCC) (Krider et al. 2006; Space Shuttle Flight Rules (FR), NASA/JSC 2004)). As a result, the Applied Meteorology Unit (AMU) developed a tool that creates an anvil threat corridor graphic that can be overlaid on satellite imagery using the Meteorological Interactive Data Display System (MIDDS, Short and Wheeler, 2002). The tool helps forecasters estimate the locations of thunderstorm anvils at one, two, and three hours into the future. It has been used extensively in launch and landing operations by both the 45 WS and SMG. The Advanced Weather Interactive Processing System (AWIPS) is now used along with MIDDS for weather analysis and display at SMG. In Phase I of this task, SMG tasked the AMU to transition the tool from MIDDS to AWIPS (Barrett et aI., 2007). For Phase II, SMG requested the AMU make the Anvil Forecast Tool in AWIPS more configurable by creating the capability to read model gridded data from user-defined model files instead of hard-coded files. An NWS local AWIPS application called AGRID was used to accomplish this. In addition, SMG needed to be able to define the pressure levels for the model data, instead of hard-coding the bottom level as 300 mb and the top level as 150 mb. This paper describes the initial development of the Anvil Forecast Tool for MIDDS, followed by the migration of the tool to AWIPS in Phase I. It then gives a detailed presentation of the Phase II improvements to the AWIPS tool.

  8. Laboratory Hydrothermal Alteration of Basaltic Tephra by Acid Sulfate Solutions: An Analog Process for Martian Weathering

    NASA Technical Reports Server (NTRS)

    Golden, D. C.; Ming, D. W.; Morris, R. V.

    2003-01-01

    The objective of this study is to conduct simulated Mars-like weathering experiments in the laboratory to determine the weathering products that might form during oxidative, acidic weathering of Mars analog materials.

  9. Physical Processes Controlling Earth's Climate

    NASA Technical Reports Server (NTRS)

    Genio, Anthony Del

    2013-01-01

    As background for consideration of the climates of the other terrestrial planets in our solar system and the potential habitability of rocky exoplanets, we discuss the basic physics that controls the Earths present climate, with particular emphasis on the energy and water cycles. We define several dimensionless parameters relevant to characterizing a planets general circulation, climate and hydrological cycle. We also consider issues associated with the use of past climate variations as indicators of future anthropogenically forced climate change, and recent advances in understanding projections of future climate that might have implications for Earth-like exoplanets.

  10. Personal Insights and Anecdotes about the Weatherization Assistance Program Process Field Study

    SciTech Connect

    Treitler, Inga

    2014-09-01

    The present report is based on the research conducted for the Process Field Study between March and September 2011. The Process Field Study documents how Weatherization Assistance Program (WAP) services were delivered to clients, and the quality with which those services were delivered. The assessments were conducted by visiting 19 agencies in 19 states around the country interviewing agency managers, staff, and contractors; observing program intake along, with 43 audits, 45 measure installation and 37 final inspections; and conducting debriefing interviews with clients and weatherization staff following the observation of service delivery. In this report, we turn to detailed observations of a few field interactions. The client stories from our observations illustrate some of the ways clients and crew interact to build the success of the program, but shows there will always be unanticipated obstacles to building trust and getting the program to the public. Stories of staff and crew career paths indicate that weatherization technology and techniques are being learned and used by technicians out of the new home construction industry and that their new knowledge provides them with technical tools and methods that many hope to take back into the construction industry if and when they return. This report is organized according to the four stages of weatherization: intake, audit, installation, and inspection. It contributes to our understanding of the area where policy, environment, culture, and individual decisions influence social innovation. The anecdotes reveal the realities of implementing programs for the benefit of the greater good at minimal cost and sacrifice in times of ever restricting budgets. As the authors revisited their field notes and compiled memorable narratives to communicate the essence of the weatherization experience, they identified three key takeaways that summarize the major issues. First, in WAP as in all services there will always be challenges to reaching the community needing to be served. Second, crew and staff learn new skills and gain experience that can be and are applied in jobs elsewhere. Finally, in the best cases, changes from the weatherization experience permeate communities in unanticipated ways.

  11. Si transfers during Archean weathering processes traced by silicon isotopes and Ge/Si ratios

    NASA Astrophysics Data System (ADS)

    Delvigne, Camille; Opfergelt, Sophie; Hofmann, Axel; Cardinal, Damien; Andr, Luc

    2015-04-01

    Weathering conditions in the Mesoarchean are poorly constrained. Recent advances in analytical capabilities have added Si isotopes and Ge/Si ratios to the repertoire of tracers used in the study of soil formation processes: neoformation of secondary clay minerals is associated with large Si isotope and Ge/Si fractionation in response to desilication processes and the weathering degree [1, 2, 3, 4]. Here we combine Si isotopes and Ge/Si ratios of a Mesoarchean paleosol (~2.95 Ga) and of nearly coeval but younger shales as proxies of weathering processes and Si mass transfer at the early Earth's surface. The paleosol is developed on andesite and shows a well defined mineralogical and chemical differentiation. In a first step, similar to modern soils, neoformation of secondary clay minerals in the paleosol was associated with fractionation of Si isotopes and Ge/Si ratios in response to chemical weathering degree and soil desilication. In a second step, the loss of Fe(II)-rich minerals, likely Fe-rich smectites, due to low pO2 conditions produced additional control on Si and Ge mobilities. Opposite fractionation behaviors are observed: products of desilication acted as 28Si and Ge sink while the leaching of Fe(II)-rich minerals released 28Si and Ge to soil solutions. Furthermore, the shales deposited immediately after the paleosol display ?30Si and Ge/Si compositions which may be explained as mixtures of the recognized Archean paleosols components. Their recording within the sedimentary pile suggests that the observed weathering-induced desilication might have been widely effective during the Mesoarchean as well as Fe(II)-rich minerals leaching in a lesser extent and pointing out these processes as determinant in the Si transfers from continents to hydrosphere. [1] Kurtz et al., (2002) Geochim. Cosmochim. Acta 66, 1525-1537 [2] Ziegler et al., (2005) Geochim. Cosmochim. Acta 69, 4597-4610. [3] Opfergelt et al., (2010) Geochim. Cosmochim. Acta 74, 225-240. [4] Steinhoefel et al., (2011) Chem. Geol. 286, 280-289.

  12. Spatial gradient of chemical weathering and its coupling with physical erosion in the soils of the Betic Cordillera (SE Spain)

    NASA Astrophysics Data System (ADS)

    Schoonejans, Jerome; Vanacker, Veerle; Opfergelt, Sophie; Ameijeiras-Mario, Yolanda; Kubik, Peter

    2015-04-01

    The production and denudation of soil material are controlled by chemical weathering and physical erosion which influence one another. Better understanding and quantification of this relationship is critical to understand biogeochemical cycles in the critical zone. The intense silicate weathering that is taking place in young mountain ranges is often cited to be a negative feedback that involves a long-term reduction of the atmospheric CO2 and the temperature cooling. However the possible (de)coupling between weathering and erosion is not fully understood for the moment and could reduce the effect of the feedback. This study is conducted in the eastern Betic Cordillera located in southeast Spain. The Betic Cordillera is composed by several mountains ranges or so-called Sierras that are oriented E-W to SE-NW and rise to 2000m.a.s.l. The Sierras differ in topographic setting, tectonic activity, and slightly in climate and vegetation. The mountain ranges located in the northwest, such as the Sierra Estancias, have the lowest uplift rates ( ~20-30 mm/kyr); while those in the southeast, such as the Sierra Cabrera, have the highest uplift rates ( >150mm/kyr). The sampling was realised into four small catchments located in three different Sierras. In each of them, two to three soil profiles were excavated on exposed ridgetops, and samples were taken by depth slices. The long-term denudation rate at the sites is inferred from in-situ 10Be CRN measurements. The chemical weathering intensity is constrained using a mass balance approach that is based on the concentration of immobile elements throughout the soil profile (CDF). Our results show that the soil depth decreases with an increase of the denudation rates. Chemical weathering accounts for 5 to 35% of the total mass lost due to denudation. Higher chemical weathering intensities (CDFs) are observed in sites with lower denudation rates (and vice versa). The data suggest that chemical weathering intensities are strongly associated with long-term 10Be derived denudation rates. Several causative factors may contribute to this observation, amongst which variation in climate, topography, and vegetation that are all associated with the measured variation in denudation rates. Finally, our data do not support a positive relation between the weathering rate and the physical erosion rate in the soil.

  13. Weathering processes as predisposing factors of the landscape evolution along plutono-metamorphic profiles of the Sila Massif, Calabria, southern Italy

    NASA Astrophysics Data System (ADS)

    Perri, Francesco; Borrelli, Luigi; Muto, Francesco; Gullà, Giovanni; Critelli, Salvatore; Conforti, Massimo; Filomena, Luciana; Rago, Valeria

    2013-04-01

    This work is aimed to join interdisciplinary research topics of weathering profile stages on plutonic (granitoid) and metamorphic (gneissic) rocks related to tectonic and landscape evolution of the western Sila Grande Massif (southern Italy). The grain-size of the studied samples is related to the parent rocks in response to physical and chemical weathering processes. Weathering processes produce an unconsolidated rock characterized by sand-gravel grain-size fraction for the granitoid rocks and by sand-silt grain-size fraction for the gneissic rocks. Chemical and mineralogical analyses confirm the granulometric observations. The difference between granitoid and gneissic rocks are mainly related to a higher content of quartz and feldspars for the first one rock type, whereas the second rock type shows higher content of neoformed clay minerals as well expandable phases. The main mineralogical changes concern the partial transformation of biotite and the partial destruction of feldspars, associated with the neoformation of secondary minerals (clay minerals and Fe-oxides) during the most advanced weathering stage; these processes also produce a substitution of the original rock fabric. All these petrological, chemical and mineralogical observations associated to microfractures and morphological variations occur on both plutonic and metamorphic original rocks and, thereby, affect the surrounding landscape processes. Generally, the granitoid profiles are regular and simple, characterized by gradual variation in the degree of weathering from bottom to top; where granitoid rocks show strong morphologies characterized by high relief energy and steep slopes, earth and debris slides, soil slips and earth flow can occur especially when fresher granitoids is near the surface and is covered by organic debris, colluvium, or soil. The gneissic profiles are characterized by structural complexity may be related to several factors such as presence of faults, high state of fracturing and the compositional heterogeneity of the gneiss. These profile characteristics are strongly related to the tectonic setting of the studied area. In particular, many fractured zone associated to fault planes and completely degraded rocks associated to thrust planes have been observed along the cutslope studied, where physical and chemical weathering produce argillified levels. These profile features represents a predisposing factor to the development of mass movements such as deep landslide (e.g., rock slide) and DSGSD (Deep Seated Gravitational Slope Deformation) in the fresher rocks. The weathering puzzle resulting from this preliminary study, based on the reconstruction of the weathering profiles in the plutonic and metamorphic rocks will help to evaluate the landslides susceptibility and hazard assessment in homogeneous geological context.

  14. Spin physics through unpolarized processes

    NASA Astrophysics Data System (ADS)

    Lu, Zhun

    2016-02-01

    This article presents a review of our present understanding of the spin structure of the unpolarized hadron. Particular attention is paid to the quark sector at leading twist, namely, the quark Boer-Mulders function, which describes the transverse polarization of the quark inside an unpolarized hadron. After introducing the operator definition of the Boer-Mulders function, a detailed treatment of different non-perturbative calculations of the Boer-Mulders functions is provided. The phenomenology in Drell-Yan processes and semi-inclusive leptoproduction, including the extraction of the quark and antiquark Boer-Mulders functions from experimental data, is presented comprehensively. Finally, prospects for future theoretical studies and experimental measurements are presented in brief.

  15. Process Coupling Between Mineral Transformation and U Speciation in Acid Waste Weathered Sediments

    NASA Astrophysics Data System (ADS)

    Perdrial, N.; Kanematsu, M.; Wang, G.; Um, W.; O'Day, P. A.; Chorover, J.

    2013-12-01

    The need for better prediction of contaminant transport motivates multi-faceted lines of inquiry to build a strong bridge between molecular- and field-scale information. At Hanford (WA), millions of liters of U-containing acidic wastes have been discharged to the soil. In order to predict reactive contaminant migration in the soil, it is necessary to determine the process coupling that occurs between mineral transformation and uranium speciation in these acid-uranium waste weathered sediments. Furthermore, we seek to establish linkages between molecular-scale contaminant speciation and meso-scale contaminant lability, release and reactive transport. Unweathered Hanford sediments were reacted for 365 days with acidic (pH 3), uranium bearing waste solutions in batch experiments. The presence and absence of phosphate in the waste as a control on uranium speciation was also investigated. At dedicated reaction times (7, 14, 30, 90, 180 and 365 days) solid and solution chemistry were analyzed to determine weathering trajectories and contaminant speciation. As observed by XRD and U-EXAFS, when present, PO4 exerted a strong controls over uranium speciation at all pH with the rapid precipitation of meta-ankoleite [K(UO2PO4).3H2O] and near complete immobilization of U. Over prolonged reaction time, however, small fractions of boltwoodite [K(UO2)(HSiO4).3H2O] increased in PO4-high U systems. When PO4 was excluded from the reaction systems, U speciation was indirectly controlled by the pH of the reactant solution and its effect on primary mineral weathering. In this case, U immobilization remained limited with 25 to 50% of the uranium precipitated as becquerelite ([Ca(UO2)6O4(OH)6.3H2O] or the K equivalent - compreignacite) and suspected boltwoodite. Differences between the systems are attributed to process coupling between acid chemistry and U geochemistry. Carbonate weathering contributed to rapidly buffer the pH to pH 7-8 in the absence of PO4 and to 6-7 in its presence, promoting subsequent silicate weathering that makes aqueous Si available for boltwoodite precipitation. Comparison with homogeneous nucleation experiments and thermodynamic calculations confirmed the strong phosphate control over U speciation and the multispeciation of U in its absence.

  16. Chemical weathering and diagenesis of a cold desert soil from Wright Valley, Antarctica - An analog of Martian weathering processes

    NASA Technical Reports Server (NTRS)

    Gibson, E. K.; Mckay, D. S.; Wentworth, S. J.

    1983-01-01

    Weathering, diagenesis, and chemical alteration of a soil profile from the Dry Valleys of Antarctica are investigated as an analog to soil development within the Martian regolith. Soil samples from a soil pit one meter deep on Prospect Mesa, Wright Valley, are examined for their major element concentrations, water-soluble cations and anions, carbon, sulfur, and water concentrations, and related petrographic characteristics of weathering in a cold, dry environment. A petrographic study of the samples suggests that most silicate mineral and lithic fragments exhibit some degree of alteration. Chemical alteration occurs both in samples above and within the permanently frozen zone. The concentrations of water-soluble cations, for example, Na(+), K(+), Ca(2+), and anions, Cl(-), SO4(2-), NO3(-), are found to decrease significantly from the surface to the permanently frozen zone, suggesting a major movement of water-soluble species. It is also found that enrichments in secondary mineral abundances correlate with the water soluble ion concentrations. The formation of zeolites is seen throughout the soil column; these, it is thought, may be reservoirs for volatile storage within the regolith.

  17. Evaluating sensitivity of silicate mineral dissolution rates to physical weathering using a soil evolution model (SoilGen2.25)

    NASA Astrophysics Data System (ADS)

    Opolot, E.; Finke, P. A.

    2015-11-01

    Silicate mineral dissolution rates depend on the interaction of a number of factors categorized either as intrinsic (e.g. mineral surface area, mineral composition) or extrinsic (e.g. climate, hydrology, biological factors, physical weathering). Estimating the integrated effect of these factors on the silicate mineral dissolution rates therefore necessitates the use of fully mechanistic soil evolution models. This study applies a mechanistic soil evolution model (SoilGen) to explore the sensitivity of silicate mineral dissolution rates to the integrated effect of other soil-forming processes and factors. The SoilGen soil evolution model is a 1-D model developed to simulate the time-depth evolution of soil properties as a function of various soil-forming processes (e.g. water, heat and solute transport, chemical and physical weathering, clay migration, nutrient cycling, and bioturbation) driven by soil-forming factors (i.e., climate, organisms, relief, parent material). Results from this study show that although soil solution chemistry (pH) plays a dominant role in determining the silicate mineral dissolution rates, all processes that directly or indirectly influence the soil solution composition play an equally important role in driving silicate mineral dissolution rates. Model results demonstrated a decrease of silicate mineral dissolution rates with time, an obvious effect of texture and an indirect but substantial effect of physical weathering on silicate mineral dissolution rates. Results further indicated that clay migration and plant nutrient recycling processes influence the pH and thus the silicate mineral dissolution rates. Our silicate mineral dissolution rates results fall between field and laboratory rates but were rather high and more close to the laboratory rates possibly due to the assumption of far from equilibrium reaction used in our dissolution rate mechanism. There is therefore a need to include secondary mineral precipitation mechanism in our formulation. In addition, there is a need for a more detailed study that is specific to field sites with detailed measurements of silicate mineral dissolution rates, climate, hydrology, and mineralogy to enable the calibration and validation of the model. Nevertheless, this study is another important step to demonstrate the critical need to couple different soil-forming processes with chemical weathering in order to explain differences observed between laboratory and field measured silicate mineral dissolution rates.

  18. Evaluating sensitivity of silicate mineral dissolution rates to physical weathering using a soil evolution model (SoilGen2.25)

    NASA Astrophysics Data System (ADS)

    Opolot, E.; Finke, P. A.

    2015-08-01

    Silicate mineral dissolution rates depend on the interaction of a number of factors categorized either as intrinsic (e.g. mineral surface area, mineral composition) or extrinsic (e.g. climate, hydrology, biological factors, physical weathering). Estimating the integrated effect of these factors on the silicate mineral dissolution rates therefore necessitates the use of fully mechanistic soil evolution models. This study applies a mechanistic soil evolution model (SoilGen) to explore the sensitivity of silicate mineral dissolution rates to the integrated effect of other soil forming processes and factors. The SoilGen soil evolution model is a 1-D model developed to simulate the time-depth evolution of soil properties as a function of various soil forming processes (e.g. water, heat and solute transport, chemical and physical weathering, clay migration, nutrient cycling and bioturbation) driven by soil forming factors (i.e., climate, organisms, relief, parent material). Results from this study show that although soil solution chemistry (pH) plays a dominant role in determining the silicate mineral dissolution rates, all processes that directly or indirectly influence the soil solution composition equally play an important role in driving silicate mineral dissolution rates. Model results demonstrated a decrease of silicate mineral dissolution rates with time, an obvious effect of texture and an indirect but substantial effect of physical weathering on silicate mineral dissolution rates. Results further indicated that clay migration and plant nutrient recycling processes influence the pH and thus the silicate mineral dissolution rates. Our silicate mineral dissolution rates results fall between field and laboratory rates but were rather high and more close to the laboratory rates owing to the assumption of far from equilibrium reaction used in our dissolution rate mechanism. There is therefore need to include secondary mineral precipitation mechanism in our formulation. In addition, there is need for a more detailed study that is specific to field sites with detailed measurements of silicate mineral dissolution rates, climate, hydrology and mineralogy to enable the calibration and validation of the model. Nevertheless, this study is another important step to demonstrate the critical need to couple different soil forming processes with chemical weathering in order to explain differences observed between laboratory and field measured silicate mineral dissolution rates.

  19. Biological processes and links to the physics

    NASA Astrophysics Data System (ADS)

    Hinrichsen, Hans-Harald

    2009-10-01

    Analysis of the temporal and spatial variability of biological processes and identification of the main variables that drive the dynamic regime of marine ecosystems is complex. Correlation between physical variables and long-term changes in ecosystems has routinely been identified, but the specific mechanisms involved remain often unclear. Reasons for this could be various: the ecosystem can be very sensitive to the seasonal timing of the anomalous physical forcing; the ecosystem can be contemporaneously influenced by many physical variables and the ecosystem can generate intrinsic variability on climate time scales. Marine ecosystems are influenced by a variety of physical factors, e.g., light, temperature, transport, turbulence. Temperature has a fundamental forcing function in biology, with direct influences on rate processes of organisms and on the distribution of mobile species that have preferred temperature ranges. Light and transport also affect the physiology and distribution of marine organisms. Small-scale turbulence determines encounter between larval fish and their prey and additionally influences the probability of successful pursuit and ingestion. The impact of physical forcing variations on biological processes is studied through long-term observations, process studies, laboratory experiments, retrospective analysis of existing data sets and modelling. This manuscript reviews the diversity of physical influences on biological processes, marine organisms and ecosystems and their variety of responses to physical forcing with special emphasis on the dynamics of zooplankton and fish stocks.

  20. Will Somebody do the Dishes? Weathering Analogies, Geologic Processes and Geologic Time

    NASA Astrophysics Data System (ADS)

    Stelling, P.; Wuotila, S.; Giuliani, M.

    2006-12-01

    A good analogy is one of the most powerful tools in any instructors' arsenal, and encouraging students to explore the links between an analogy and a scientific concept can cement both ideas in a student's mind. A common analogy for weathering and erosion processes is doing the dishes. Oxidation, hydration, and solution reactions can be intimidating on the chalkboard but easily understood in the context of cleaning up after dinner. Rather than present this analogy as a lecture demonstration, students are encouraged to experimentally determine which type of weathering works best on their dirty dishes. The experiment must use at least four identically dirty dishes: three experimental dishes and one control dish. The experimental dishes are subjected to simulated weathering and erosion processes of the student's design. Common techniques developed by students are cold or warm water baths, baths with and without acid (lemon juice or soda), and freeze-thaw cycles. Occasionally creative experiments result in unexpected discoveries, such the inefficiency of abrasion from wind-blown sand, especially when compared to soaking dishes in Canadian Whiskey. The effectiveness of each experimental run is determined by comparison to the control plate after loose debris is removed from each. The dish with the smallest aerial extent of remaining food is the declared the most effective. Discussion sections of the experimental write-up includes a description of which geologic processes were being simulated in each experiment, comparisons of the effectiveness of each techniques, and statements of how these experiments differ from reality. In order to advance this project, a second stage of the assignment, a direct comparison of weathering and erosion techniques on food and on geologic materials, will be added this fall. Ideally, students will empirically derive erosion rates and calculate the time required to remove the volume of material represented by a geologically important feature, such as Mt. Rainier or the Grand Canyon. In the end, students completing this project gain an understanding of how geologic processes work, the time scales required, the differences between analogies and the real thing, and arguably the most important aspect, a best-practices approach to doing the dishes.

  1. Physically coherent probabilistic weather forecasts via discrete copula-based ensemble postprocessing methods

    NASA Astrophysics Data System (ADS)

    Schefzik, Roman; Thorarinsdottir, Thordis; Gneiting, Tilmann

    2015-04-01

    State-of-the-art weather forecasts depend on ensemble prediction systems, which consist of multiple runs of dynamical numerical weather prediction models differing in the initial conditions and/or the parameterized numerical representation of the atmosphere. Statistical postprocessing of the ensemble forecasts can address biases and dispersion errors. However, current postprocessing approaches are mostly univariate and apply to a single weather quantity at a single location and for a single prediction horizon only. Such methods do not account for dependencies which are crucial in many applications. Multivariate postprocessing approaches based on empirical copulas offer appealing options to address this. The ensemble copula coupling (ECC) method uses the empirical copula of the raw ensemble to aggregate samples from predictive distributions obtained by univariate postprocessing. It captures the spatial, temporal and inter-variable rank dependence pattern of the unprocessed raw ensemble. Proceeding in a similar manner, the Schaake shuffle alternatively captures dependence structures of past observations rather than ensemble forecasts. A specific implementation of the Schaake shuffle employs historical observation data from past dates for which the corresponding ensemble forecast resembles the current one. The methods are illustrated and tested using real weather forecast data provided by the European Centre for Medium-Range Weather Forecasts.

  2. Interface-coupled dissolution-precipitation processes during acidic weathering of multicomponent minerals

    NASA Astrophysics Data System (ADS)

    Ruiz-Agudo, Encarnacion; King, Helen E.; Patiño-López, Luis D.; Putnis, Christine V.; Geisler, Thorsten; Rodriguez-Navarro, Carlos M.; Putnis, Andrew

    2015-04-01

    The chemical weathering of carbonate and silicate minerals on the Earth's surface controls important geochemical processes such as erosion rates and soil formation, ore genesis or climate evolution. The dissolution of most of these minerals is typically incongruent, and results in the formation of surface coatings (altered layers, also known as leached layers). These coatings may significantly affect mineral dissolution rates over geological timescales, and therefore a great deal of research has been conducted on them. However, the mechanism of leached layer formation is a matter of vigorous debate. Here we report on an in situ atomic force microscopy (AFM) and real-time Mach-Zehnder phase-shift interferometry (PSI) study of the dissolution of wollastonite, CaSiO3, and dolomite, CaMg(CO3)2, as an example of surface coating formation during acidic weathering of multicomponent minerals. Our in situ results provide clear direct experimental evidence that leached layers are formed in a tight interface-coupled two-step process: stoichiometric dissolution of the pristine mineral surfaces and subsequent precipitation of a secondary phase (silica in the case of wollastonite, or hydrated magnesium carbonate in the case of dolomite) from a supersaturated boundary layer of fluid in contact with the mineral surface. This occurs despite the bulk solution remaining undersaturated with respect to the secondary phase. The validation of such a mechanism given by the results reported here completely changes the conceptual framework concerning the mechanism of chemical weathering, and differs significantly from the concept of preferential leaching of cations postulated by most currently accepted incongruent dissolution models.

  3. Rock Abrasion as Seen by the MSL Curiosity Rover: Insights on Physical Weathering on Mars

    NASA Astrophysics Data System (ADS)

    Bridges, N.; Day, M. D.; Le Mouelic, S.; Martin-Torres, F. J.; Newsom, H. E.; Sullivan, R. J., Jr.; Ullan, A.; Wiens, R. C.; Zorzano, M. P.

    2014-12-01

    Mars is a dry planet, with actively blowing sand in many regions. In the absence of stable liquid water and an active hydrosphere, rates of chemical weathering are slow, such that aeolian abrasion is a dominant agent of landscape modification where sand is present and winds above threshold occur at sufficient frequency. Reflecting this activity, ventifacts, rocks that have been abraded by windborne particles, and wind-eroded outcrops, are common. They provide invaluable markers of the Martian wind record and insight into climate and landscape modification. Ventifacts are distributed along the traverse of the Mars Science Laboratory Curiosity rover. They contain one or more diagnostic features and textures: Facets, keels, basal sills, elongated pits, scallops/flutes, grooves, rock tails, and lineations. Keels at the junction of facets are sharp enough to pose a hazard MSL's wheels in some areas. Geomorphic and textural patterns on outcrops indicate retreat of windward faces. Moonlight Valley and other depressions are demarcated by undercut walls and scree boulders, with the valley interiors containing fewer rocks, most of which show evidence for significant abrasion. Together, this suggests widening and undercutting of the valley walls, and erosion of interior rocks, by windblown sand. HiRISE images do not show any dark sand dunes in the traverse so far, in contrast to the large dune field to the south that is migrating up to 2 m per year. In addition, ChemCam shows that the rock Bathurst has a rind rich in mobile elements that would be removed in an abrading environment. This indicates that rock abrasion was likely more dominant in the past, a hypothesis consistent with rapid scarp retreat as suggested by the cosmogenic noble gases in Yellowknife Bay. Ventifacts and evidence for bedrock abrasion have also been found at the Pathfinder, Spirit, and Opportunity sites, areas, like the Curiosity traverse so far, that lack evidence for current high sand fluxes. Yardangs are also common on the planet, regardless of whether local sand is mobile. This suggest that abrasion on Mars is an episodic process driven by the passage of sand in which rock retreat rates, based on fluxes of current active dunes, may reach 10s of microns per year. Such a process has acted, over long time scales, to imprint upon the surface a record of sand activity.

  4. Major ion chemistry of the Son River, India: Weathering processes, dissolved fluxes and water quality assessment

    NASA Astrophysics Data System (ADS)

    Maharana, Chinmaya; Gautam, Sandeep Kumar; Singh, Abhay Kumar; Tripathi, Jayant K.

    2015-08-01

    River Son, draining diverse lithologies in the subtropical climate of the peninsular sub-basin of the Ganga basin, is one of the major tributaries of the Ganga River. The chemistry of major ions in the surface water of the Son River was studied in detail to determine various source(s) and processes controlling its water chemistry, seasonal and spatial variations in water chemistry, dissolved fluxes and chemical denudation rate (CDR). The study shows that Ca2+, Mg2+ and HCO 3- are major ionic species in the river water. Most of the measured parameters exhibit a relatively lower concentration in the post-monsoon as compared to pre-monsoon season. The water chemistry highlights the influence of continental weathering aided by secondary contributions from ground water, saline/alkaline soils and anthropogenic activities in the catchment. Results also reflect the dominance of carbonate weathering over silicate weathering in controlling water composition. The Son River delivers about 4.2 million tons of dissolved loads annually to the Ganga River, which accounts for ˜6% of the total annual load carried by the Ganga River to the Bay of Bengal. The average CDR of the Son River is 59.5 tons km -2 yr -1, which is less than the reported 72 tons km -2 yr -1 of the Ganga River and higher than the global average of 36 tons km -2 yr -1. The water chemistry for the pre-monsoon and post-monsoon periods shows a strong seasonal control on solute flux and CDR values. The water chemistry indicates that the Son River water is good to excellent in quality for irrigation and also suitable for drinking purposes.

  5. Weathering and weathering rates of natural stone

    SciTech Connect

    Winkler, E.M. )

    1987-01-01

    Physical and chemical weathering were studied as separate processes in the past. Recent research, however, shows that most processes are physicochemical in nature. The rates at which calcite and silica weather by dissolution are dependent on the regional and local climatic environment. The weathering of silicate rocks leaves discolored margins and rinds, a function of the ricks permeability and of the climatic parameters. Salt action, the greatest disruptive factor, is complex and not yet fully understood in all its phases, but some of th causes of disruption are crystallization pressure, hydration pressure, and hygroscopic attraction of excess moisture. The decay of marble is complex, an interaction between dissolution, crack-corrosion, and the expansion-contraction cycles triggered by the release of residual stresses. Thin spalls of granites commonly found near the street level of buildings are generally caused by a combination of stress relief and salt action. To study and determine weathering rates of a variety of commercial stones, the National Bureau of Standards erected a Stone Exposure Test Wall in 1948. Of the many types of stone represented, only a few fossiliferous limestones permit a valid measurement of surface reduction in a polluted urban environment.

  6. Physical conditions for the r-process

    SciTech Connect

    Wanajo, S.; Tachibana, T.; Goriely, S.

    2012-11-12

    Recent works show that the r-process can proceed by competition between neutron capture and {beta}-decay in low temperature environments (< 5 Multiplication-Sign 10{sup 8} K; cold r-process) where photo-disintegration plays no role. This is in contrast to the traditional picture of the r-process in high temperature environments ({approx} 1 Multiplication-Sign 10{sup 9} K; hot r-process) where the (n, {gamma})-({gamma}, n) equilibrium holds. In this study, we explore nucleosynthesis calculations based on a site-independent model to elucidate the physical conditions leading to cold and hot r-processes.

  7. Physical conditions for the r-process

    NASA Astrophysics Data System (ADS)

    Wanajo, S.; Tachibana, T.; Goriely, S.

    2012-11-01

    Recent works show that the r-process can proceed by competition between neutron capture and β-decay in low temperature environments (< 5 × 108 K; cold r-process) where photo-disintegration plays no role. This is in contrast to the traditional picture of the r-process in high temperature environments (~ 1 × 109 K; hot r-process) where the (n, γ)-(γ, n) equilibrium holds. In this study, we explore nucleosynthesis calculations based on a site-independent model to elucidate the physical conditions leading to cold and hot r-processes.

  8. Displaying Composite and Archived Soundings in the Advanced Weather Interactive Processing System

    NASA Technical Reports Server (NTRS)

    Barrett, Joe H., III; Volkmer, Matthew R.; Blottman, Peter F.; Sharp, David W.

    2008-01-01

    This presentation describes work done by the Applied Meteorology Unit (AMU) to add composite soundings to the Advanced Weather Interactive Processing System (AWIPS). This allows National Weather Service (NWS) forecasters to compare the current atmospheric state with climatology. In a previous task, the AMU created composite soundings for four rawinsonde observation stations in Florida, for each of eight flow regimes. The composite soundings were delivered to the NWS Melbourne (MLB) office for display using the NSHARP software program. NWS MLB requested that the AMU make the composite soundings available for display in AWIPS. The AMU first created a procedure to customize AWIPS so composite soundings could be displayed. A unique four-character identifier was created for each of the 32 composite soundings. The AMIU wrote a Tool Command Language/Tool Kit (TclITk) software program to convert the composite soundings from NSHARP to Network Common Data Form (NetCDF) format. The NetCDF files were then displayable by AWIPS.

  9. Identifying weathering processes by Si isotopes in two small catchments in the Black Forest (Germany)

    NASA Astrophysics Data System (ADS)

    Steinhoefel, G.; Breuer, J.; von Blanckenburg, F.; Horn, I.; Kaczorek, D.; Sommer, M.

    2013-12-01

    Stable Si isotopes are potentially an ideal proxy to investigate weathering as the release or precipitation of Si during abiotic or biotic processes causes significant shifts in the isotope signature depending on the weathering intensity. In this study, we determine the Si isotope signature of spring and stream waters and of the principle Si pools of typical soil profiles within two small catchments located on sandstone and paragneiss, respectively, in the cold, perhumid Black Forest (Germany). The Si isotope data were obtained on a Neptune MC-ICP-MS in solution for the water samples and in situ by coupling a UV femtosecond laser ablation system for solid samples, respectively. Bulk soils show a largely homogeneous Si isotope signature for different horizons and locations, which is close to those of bulk bedrocks with δ30Si value around -0.3‰. Soil clay formation is associated with limited Si mobility, which preserves initial Si isotope signatures of parental minerals. Biogenic mineral, i.e. phytoliths, exhibit negative Si isotope signature of about -0.4‰. An exception are the topsoil layers in the paragneiss catchment where the organic-rich environment promotes high Si mobility leading to a significant depletion of heavy Si isotopes. Springs and streams, sampled in spring and late summer, vary between -0.7 to 1.1‰ in δ30Si showing spatial and temporal variations dependent on the water pathways. Groundwater originated from sandstone and overlying periglacial debris layers reveals constant δ30Si values of 0.3 to 0.5‰, which is attributed to kaolinite formation. In contrast, water passing the soil zone shows very variable signatures. Low δ30Si values down to -0.7‰ most likely reflects dissolution processes of clay minerals and phytoliths during spring. In late summer, positive δ30Si values expose the impact of preferential uptake of light Si isotopes by plants. In the paragneiss catchment, this effect is likely increased by co-precipitation of isotopically light Si with Fe-oxides, which shifts surface water to δ30Si values up to 1.1‰. The Si isotope signature of the main stream depends on variable proportion of inflowing surface water and groundwater. The results on these small catchments demonstrate that Si isotopes are a powerful tool to identify weathering processes and the sources of dissolved Si, which can now be used to constrain the isotope signature of large river systems.

  10. A novel process for recovering rare earth from weathered black earth

    SciTech Connect

    Chi, R.; Zhu, G.; Zhou, Z.; Xu, Z.

    2000-02-01

    A novel process for recovering rare-earth (RE) elements from weathered-black-earth slime is developed. This process involves the initial removal of Mn by reduction leaching using SO{sub 2} followed by ammonium chloride roasting of the residual solids from the leaching process. The controlled roasting selectively converts RE oxides to water-soluble RE chlorides. The roasted materials are then dispersed in warm water (75 C) to extract RE, while water-insoluble iron oxides remain in gangue sludge, minimizing iron impurities in final RE products and hence simplifying the purification process. Lead chloride precipitates are obtained by cooling the leachate to {minus}10 C, and RE is recovered using oxalic acid precipitation. With this new process, a product of 92 pct purity at a RE recovery greater than 65 pct is obtained. In addition, Mn and Pb are recovered as by-products, with a recovery of 64 and 54 pct, respectively. The effect of operating variables on RE recovery is examined and the process chemistry described.

  11. Spectral evidence of size dependent space weathering processes on asteroid surfaces

    NASA Technical Reports Server (NTRS)

    Gaffey, M. J.; Bell, J. F.; Brown, R. H.; Burbine, T. H.; Piatek, J. L.; Reed, K. L.; Chaky, D. A.

    1993-01-01

    Most compositional characterizations of the minor planets are derived from analysis of visible and near-infrared reflectance spectra. However, such spectra are derived from light which has only interacted with a very thin surface layer. Although regolith processes are assumed to mix all near-surface lithologic units into this layer, it has been proposed that space weathering processes can alter this surface layer to obscure the spectral signature of the bedrock lithology. It has been proposed that these spectral alteration processes are much less pronounced on asteroid surfaces than on the lunar surface, but the possibility of major spectral alteration of asteroidal optical surfaces has been invoked to reconcile S-asteroids with ordinary chondrites. The reflectance spectra of a large subset of the S-asteroid population have been analyzed in a systematic investigation of the mineralogical diversity within the S-class. In this sample, absorption band depth is a strong function of asteroid diameter. The S-asteroid band depths are relatively constant for objects larger than 100 km and increase linearly by factor of two toward smaller sizes (approximately 40 km). Although the S-asteroid surface materials includes a diverse variety of silicate assemblages, ranging from dunites to basalts, all compositional subtypes of the S-asteroids conform to this trend. The A-, R-, and V-type asteroids which are primarily silicate assemblages (as opposed to the metal-silicate mixtures of most S-asteroids) follow a parallel but displaced trend. Some sort of textural or regolith equilibrium appears to have been attained in the optical surfaces of asteroids larger than about 100 km diameter but not on bodies below this size. The relationships between absorption band depth, spectral slope, surface albedo and body size provide an intriguing insight into the nature of the optical surfaces of the S-asteroids and space weathering on these objects.

  12. Environmental tracers for elucidating the weathering process in a phosphogypsum disposal site: Implications for restoration

    NASA Astrophysics Data System (ADS)

    Pérez-López, Rafael; Nieto, José M.; de la Rosa, Jesús D.; Bolívar, Juan P.

    2015-10-01

    This study provides geochemical data with the aim of identifying and tracing the weathering of phosphogypsum wastes stack-piled directly on salt-marshes of the Tinto River (Estuary of Huelva, SW Spain). With that purpose, different types of highly-polluted acid solutions were collected in the stack. Connection between these solutions and the estuarine environment was studied by geochemical tracers, such as rare earth elements (REE) and their North American Shale Composite (NASC)-normalized patterns and Cl/Br ratios. Phosphogypsum-related wastewaters include process water stored on the surface, pore-water contained in the phosphogypsum profile and edge outflow water emerging from inside the stack. Edge outflow waters are produced by waterlogging at the contact between phosphogypsum and the nearly impermeable marsh surface and discharge directly into the estuary. Process water shows geochemical characteristics typical of phosphate fertilizers, i.e. REE patterns with an evident enrichment of heavy-REE (HREE) with respect to middle-REE (MREE) and light-REE (LREE). By contrast, REE patterns of deeper pore-water and edge outflows are identical to those of Tinto River estuary waters, with a clear enrichment of MREE relative to LREE and HREE denoting influence of acid mine drainage. Cl/Br ratios of these solutions are very close to that of seawater, which also supports its estuarine origin. These findings clearly show that process water is not chemically connected with edge outflows through pore-waters, as was previously believed. Phosphogypsum weathering likely occurs by an upward flow of seawater from the marsh because of overpressure and permeability differences. Several recommendations are put forward in this study to route restoration actions, such as developing treatment systems to improve the quality of the edge outflow waters before discharging to the receiving environment.

  13. Some topics on geochemistry of weathering: a review.

    PubMed

    Formoso, Milton L L

    2006-12-01

    Weathering is a complex process comprising physical disaggregation, chemical and biological decomposition of rocks and minerals transforming complex structure minerals in simpler ones. Hydrolysis of silicates is perhaps the most important process but associated certainly to biological weathering. It is discussed the role ofwaters: activities/concentrations of chemical species, pH, Eh, importance of complexes. Weathering is not only a destructive process. It can concentrate chemical species and form mineral deposits (kaolin, bauxite, Fe, Mn, P, Nb, Au). Weathering studies are important in pedology, engineering geology, hydrogeology, paleoclimatology and ecology. The use of stonemeal is based upon the study of rock weathering. PMID:17143414

  14. Space plasma physics: I - Stationary processes

    NASA Technical Reports Server (NTRS)

    Hasegawa, Akira; Sato, Tetsuya

    1989-01-01

    The physics of stationary processes in space plasmas is examined theoretically in an introduction intended for graduate students. The approach involves the extensive use of numerical simulations. Chapters are devoted to fundamental principles, small-amplitude waves, and the stationary solar plasma system; typical measurement data and simulation results are presented graphically.

  15. Physical processes in gamma-ray bursts

    NASA Astrophysics Data System (ADS)

    Katz, J. I.

    1982-09-01

    Physical processes occurring in gamma-ray bursts are discussed, with special attention to the event of March 5, 1979 in the Large Magellanic Cloud. The source of that event's extraordinary intense line and continuum radiation has been explained as a pair plasma confined in a strong magnetic field, as in a neutron star magnetosphere, and some consequences of that model are studied. The magnetic field (approximately 10 to the 13th gauss) affects both plasma physical processes and annihilation, so that accurate measurements of the annihilation line shape may lead to quantitative field determinations. A simple model for gamma-gamma pair production and annihilation is calculated, implying that this process will not prevent escape of intense gamma-ray fluxes. Finally, energetic considerations suggest that the magnetospheric energy may be regenerated from internal sources, either during or between bursts.

  16. Process for the physical segregation of minerals

    DOEpatents

    Yingling, Jon C.; Ganguli, Rajive

    2004-01-06

    With highly heterogeneous groups or streams of minerals, physical segregation using online quality measurements is an economically important first stage of the mineral beneficiation process. Segregation enables high quality fractions of the stream to bypass processing, such as cleaning operations, thereby reducing the associated costs and avoiding the yield losses inherent in any downstream separation process. The present invention includes various methods for reliably segregating a mineral stream into at least one fraction meeting desired quality specifications while at the same time maximizing yield of that fraction.

  17. Analyzing the Role of Biofilm in Weathering Processes in the Rhizosphere with Various Microscopic Techniques

    NASA Astrophysics Data System (ADS)

    Niedziela, S.; Greenberg, K. A.; Dohnalkova, A.; Arey, B.; Balogh-Brunstad, Z.

    2011-12-01

    Biofilm is thought to have a significant role in biological weathering of minerals in the rhizosphere (root systems). The goal of our study is to examine the characteristics of rhizospheric biofilms under a range of base cation limitations and determine the best microscopic techniques to analyze the biofilm-microbe-fungus-mineral interface. We hypothesized that tree-fungus-bacteria association increases biofilm formation under severe base cation limitations that enhance mineral weathering rate and improve potassium and calcium retention and transport to the trees. Our hypothesis was tested in samples from a growth column experiment. Red pine (Pinus resinosa) trees were grown in leach tubes in quartz sand amended with 1 wt% biotite and anorthite. Half of the trees were inoculated with Suillus tomentosus and a group of soil bacteria, and the other half were left without microbial inoculation. Columns without any biology added served as controls. Calcium and potassium were supplied in irrigation water in 0, 30, 60 and 100% of an amount for healthy tree growth and the concentration of all other nutrients stayed constant in all solutions. After four weeks, the columns were destructively sampled and the root systems were analyzed by various microscopic techniques such as helium ion microscopy (HeIM), scanning electron microscopy (SEM) coupled with focused ion beam (FIB) and energy dispersive x-ray spectroscopy (EDS), cryo-SEM, and high resolution transmission electron microscopy (TEM) also coupled with EDS. These techniques were employed to collect the most information about the biofilm-microbe-fungus-mineral interface. The HeIM uses a beam of helium ions to produce 3-D high resolution images with greater depth of field than SEM and produces detailed surface topography results. The SEM coupled with EDS gives detailed chemical distribution of elements on a surface topography. The SEM coupled with FIB produces a cross-section of the analyzed material and allows a view inside of the sample. It also allows preparing a thin section of a selected area, which could be transferred to the TEM for correlative imaging and analyses providing high resolution structural and chemical information of the biofilm-microbe-fungus-mineral interface. Using cryo-SEM complements the above results with preserving the specimen in its real, hydrated state that allows the characterization of the original topography and cross-section. The combinations of these state-of-the-art techniques shed new light on the characteristics of biofilm-microbe-fungus-mineral interface and provide information about weathering processes, rates, and base cation immobilization in soils.

  18. Creating Interactive Graphical Overlays in the Advanced Weather Interactive Processing System Using Shapefiles and DGM Files

    NASA Technical Reports Server (NTRS)

    Barrett, Joe H., III; Lafosse, Richard; Hood, Doris; Hoeth, Brian

    2007-01-01

    Graphical overlays can be created in real-time in the Advanced Weather Interactive Processing System (AWIPS) using shapefiles or Denver AWIPS Risk Reduction and Requirements Evaluation (DARE) Graphics Metafile (DGM) files. This presentation describes how to create graphical overlays on-the-fly for AWIPS, by using two examples of AWIPS applications that were created by the Applied Meteorology Unit (AMU) located at Cape Canaveral Air Force Station (CCAFS), Florida. The first example is the Anvil Threat Corridor Forecast Tool, which produces a shapefile that depicts a graphical threat corridor of the forecast movement of thunderstorm anvil clouds, based on the observed or forecast upper-level winds. This tool is used by the Spaceflight Meteorology Group (SMG) at Johnson Space Center, Texas and 45th Weather Squadron (45 WS) at CCAFS to analyze the threat of natural or space vehicle-triggered lightning over a location. The second example is a launch and landing trajectory tool that produces a DGM file that plots the ground track of space vehicles during launch or landing. The trajectory tool can be used by SMG and the 45 WS forecasters to analyze weather radar imagery along a launch or landing trajectory. The presentation will list the advantages and disadvantages of both file types for creating interactive graphical overlays in future AWIPS applications. Shapefiles are a popular format used extensively in Geographical Information Systems. They are usually used in AWIPS to depict static map backgrounds. A shapefile stores the geometry and attribute information of spatial features in a dataset (ESRI 1998). Shapefiles can contain point, line, and polygon features. Each shapefile contains a main file, index file, and a dBASE table. The main file contains a record for each spatial feature, which describes the feature with a list of its vertices. The index file contains the offset of each record from the beginning of the main file. The dBASE table contains records for each attribute. Attributes are commonly used to label spatial features. Shapefiles can be viewed, but not created in AWIPS. As a result, either third-party software can be installed on an AWIPS workstation, or new software must be written to create shapefiles in the correct format.

  19. Meteorites on Mars as Planetary Research Tools with Special Considerations for Martian Weathering Processes

    NASA Astrophysics Data System (ADS)

    Ashley, James Warren

    2011-09-01

    The occurrence of exogenic, meteoritic materials on the surface of any world presents opportunities to explore a variety of significant problems in the planetary sciences. In the case of Mars, meteorites found on its surface may help to (1) constrain atmospheric conditions during their time of arrival; (2) provide insights into possible variabilities in meteoroid type sampling between Mars and Earth space environments; (3) aid in our understanding of soil, dust, and sedimentary rock chemistry; (4) assist with the calibration of crater-age dating techniques; and (5) provide witness samples for chemical and mechanical weathering processes. The presence of reduced metallic iron in approximately 88 percent of meteorite falls renders the majority of meteorites particularly sensitive to oxidation by H2O interaction. This makes them excellent markers for H2O occurrence. Several large meteorites have been discovered at Gusev Crater and Meridiani Planum by the Mars Exploration Rovers (MERs). Significant morphologic characteristics interpretable as weathering features in the Meridiani suite of iron meteorites include a (1) large pit lined with delicate iron protrusions suggestive of inclusion removal by corrosive interaction; (2) differentially eroded kamacite and taenite lamellae on three of the meteorites, providing relative timing through cross-cutting relationships with deposition of (3) an iron oxide-rich dark coating; and (4) regmaglypted surfaces testifying to regions of minimal surface modification; with other regions in the same meteorites exhibiting (5) large-scale, cavernous weathering. Iron meteorites found by Mini-TES at both Meridiani Planum and Gusev Crater have prompted laboratory experiments designed to explore elements of reflectivity, dust cover, and potential oxide coatings on their surfaces in the thermal infrared using analog samples. Results show that dust thickness on an iron substrate need be only one tenth as great as that on a silicate rock to obscure its infrared signal. In addition, a database of thermal emission spectra for 46 meteorites was prepared to aid in the on-going detection and interpretation of these valuable rocks on Mars using Mini-TES instruments on both MER spacecraft. Applications to the asteroidal sciences are also relevant and intended for this database.

  20. Reproducibility of Carbon and Water Cycle by an Ecosystem Process Based Model Using a Weather Generator and Effect of Temporal Concentration of Precipitation on Model Outputs

    NASA Astrophysics Data System (ADS)

    Miyauchi, T.; Machimura, T.

    2014-12-01

    GCM is generally used to produce input weather data for the simulation of carbon and water cycle by ecosystem process based models under climate change however its temporal resolution is sometimes incompatible to requirement. A weather generator (WG) is used for temporal downscaling of input weather data for models, where the effect of WG algorithms on reproducibility of ecosystem model outputs must be assessed. In this study simulated carbon and water cycle by Biome-BGC model using weather data measured and generated by CLIMGEN weather generator were compared. The measured weather data (daily precipitation, maximum, minimum air temperature) at a few sites for 30 years was collected from NNDC Online weather data. The generated weather data was produced by CLIMGEN parameterized using the measured weather data. NPP, heterotrophic respiration (HR), NEE and water outflow were simulated by Biome-BGC using measured and generated weather data. In the case of deciduous broad leaf forest in Lushi, Henan Province, China, 30 years average monthly NPP by WG was 10% larger than that by measured weather in the growing season. HR by WG was larger than that by measured weather in all months by 15% in average. NEE by WG was more negative in winter and was close to that by measured weather in summer. These differences in carbon cycle were because the soil water content by WG was larger than that by measured weather. The difference between monthly water outflow by WG and by measured weather was large and variable, and annual outflow by WG was 50% of that by measured weather. The inconsistency in carbon and water cycle by WG and measured weather was suggested be affected by the difference in temporal concentration of precipitation, which was assessed.

  1. Physical processes in spin polarized plasmas

    SciTech Connect

    Kulsrud, R.M.; Valeo, E.J.; Cowley, S.

    1984-05-01

    If the plasma in a nuclear fusion reactor is polarized, the nuclear reactions are modified in such a way as to enhance the reactor performance. We calculate in detail the modification of these nuclear reactions by different modes of polarization of the nuclear fuel. We also consider in detail the various physical processes that can lead to depolarization and show that they are by and large slow enough that a high degree of polarization can be maintained.

  2. Physical processes causing the formation of penitentes.

    PubMed

    Claudin, P; Jarry, H; Vignoles, G; Plapp, M; Andreotti, B

    2015-09-01

    Snow penitentes form in sublimation conditions by differential ablation. Here we investigate the physical processes at the initial stage of penitente growth and perform the linear stability analysis of a flat surface submitted to the solar heat flux. We show that these patterns do not simply result from the self-illumination of the surface-a scale-free process-but are primarily controlled by vapor diffusion and heat conduction. The wavelength at which snow penitentes emerge is derived and discussed. We found that it is controlled by aerodynamic mixing of vapor above the ice surface. PMID:26465564

  3. Physical processes causing the formation of penitentes

    NASA Astrophysics Data System (ADS)

    Claudin, P.; Jarry, H.; Vignoles, G.; Plapp, M.; Andreotti, B.

    2015-09-01

    Snow penitentes form in sublimation conditions by differential ablation. Here we investigate the physical processes at the initial stage of penitente growth and perform the linear stability analysis of a flat surface submitted to the solar heat flux. We show that these patterns do not simply result from the self-illumination of the surfacea scale-free processbut are primarily controlled by vapor diffusion and heat conduction. The wavelength at which snow penitentes emerge is derived and discussed. We found that it is controlled by aerodynamic mixing of vapor above the ice surface.

  4. Automating the initial physics chart checking process.

    PubMed

    Furhang, Eli E; Dolan, James; Sillanpaa, Jussi K; Harrison, Louis B

    2009-01-01

    The initial physics chart check, an essential quality assurance process, verifies that the physician intent is properly expressed in the treatment plan, the treatment plan is reasonable, and the Record and Verify (RV) system properly captures the plan parameters. In this work the process was automated by characterizing the initial physics chart check as a universal set of steps, compartmentalized into intra-plan and inter-plan reviews. The intra-plan review confirms the diagnosis-prescription-plan correlation, and verifies transfer accuracy of the signed treatment plan parameters into the RV system. The inter-plan review tabulates all RV parameters for similar cases, and highlights outliers. The tabulation of RV parameters for similar cases enables a summation of experience across staff members, and facilitates a comparison using the Statistical Process Control (SPC) formalism. A summary sheet, added to each reviewed chart, automatically documents deviations noted during the review process. Forty-five patient charts were analyzed using the software. The length of time for the entire initial chart-checking process was reduced from about an hour to a few minutes. The code developed in this work allows the user to consider the big picture, trusting the software to track details. PMID:19223834

  5. Soil redistribution and weathering controlling the fate of geochemical and physical carbon stabilization mechanisms in soils of an eroding landscape

    NASA Astrophysics Data System (ADS)

    Doetterl, S.; Cornelis, J.-T.; Six, J.; Bod, S.; Opfergelt, S.; Boeckx, P.; Van Oost, K.

    2015-03-01

    The role of eroding landscapes in organic carbon stabilization operating as C sinks or sources has been frequently discussed, but the underlying mechanisms are not fully understood. Our analysis aims to clarify the effects of soil redistribution on physical and biogeochemical soil organic carbon (SOC) stabilization mechanisms along a hillslope transect. The observed mineralogical differences seem partly responsible for the effectiveness of geochemical and physical SOC stabilization mechanisms as the mineral environment along the transect is highly variable and dynamic. The abundance of primary and secondary minerals and the weathering status of the investigated soils differ drastically along this transect. Extractable iron and aluminum components are generally abundant in aggregates, but show no strong correlation to SOC, indicating their importance for aggregate stability but not for SOC retention. We further show that pyrophosphate extractable soil components, especially manganese, play a role in stabilizing SOC within non-aggregated mineral fractions. The abundance of microbial residues and measured 14C ages for aggregated and non-aggregated SOC fractions demonstrate the importance of the combined effect of geochemical and physical protection to stabilize SOC after burial at the depositional site. Mineral alteration and the breakdown of aggregates limit the protection of C by minerals and within aggregates temporally. The 14C ages of buried soil indicate that C in aggregated fractions seems to be preserved more efficiently while C in non-aggregated fractions is released, allowing a re-sequestration of younger C with this fraction. Old 14C ages and at the same time high contents of microbial residues in aggregates suggest either that microorganisms feed on old carbon to build up microbial biomass or that these environments consisting of considerable amounts of old C are proper habitats for microorganisms and preserve their residues. Due to continuous soil weathering and, hence, weakening of protection mechanisms, a potential C sink through soil burial is finally temporally limited.

  6. Mineralogy of weathering processes on the spoil dumps in the Ostrava-Karvina Coal District

    SciTech Connect

    Matysek, D.; Bielesz, M.

    1994-12-31

    Exploitation of coal in the Ostrava-Karvina Coal District is accompanies by the accumulation of large amounts of waste materials: spoil rocks from mine works, wastes from processing plants, and coal slurries. This waste often is sued for landscape preparation, or it is deposited on spoil dumps. According to their composition, carboniferous materials (siltstones, silt-claystones with admixtures of coal matter prevailing, and fine-grained feldspathic sandstones and subgraywackes) are considered to be relatively harmless to the environment. Problems resulting from reclaiming spoil dumps have resulted in more detailed study of the relationship between carboniferous materials and the environment, specifically, the relationship between spoil dumps and such factors as the ecosystems and acidification, geochemical reactivity of carboniferous rocks,a nd stability of minerals. Geological processes of environmental concern in this case include the mineralogy of weathering products with production of salts (evaporation) and the degradation of clay fractions. Geochemical and botanical factors of origin of soils on spoil dumps were described by Stalmachova and Matysek. The authors report a study in which changes in the clay minerals from dumps are compared with paragneiss of clay minerals on the carboniferous outcrops.

  7. Day Length and Weather Effects on Children’s Physical Activity and Participation in Play, Sports, and Active Travel

    PubMed Central

    Goodman, Anna; Paskins, James; Mackett, Roger

    2013-01-01

    Background Children in primary school are more physically active in the spring/summer. Little is known about the relative contributions of day length and weather, however, or about the underlying behavioral mediators. Methods 325 British children aged 8 to 11 wore accelerometers as an objective measure of physical activity, measured in terms of mean activity counts. Children simultaneously completed diaries in which we identified episodes of out-of-home play, structured sports, and active travel. Our main exposure measures were day length, temperature, rainfall, cloud cover, and wind speed. Results Overall physical activity was higher on long days (≥ 14 hours daylight), but there was no difference between short (< 9.5 hours) and medium days (10.2–12.6 hours). The effect of long day length was largest between 5 PM and 8 PM, and persisted after adjusting for rainfall, cloud cover, and wind. Up to half this effect was explained by a greater duration and intensity of out-of-home play on long days; structured sports and active travel were less affected by day length. Conclusions At least above a certain threshold, longer afternoon/evening daylight may have a causal role in increasing child physical activity. This strengthens the public health arguments for daylight saving measures such as those recently under consideration in Britain. PMID:22826506

  8. Characterizing the process and quantifying the rate of subaerial rock weathering on desert surfaces using roughness analysis

    NASA Astrophysics Data System (ADS)

    Mushkin, Amit; Sagy, Amir; Trabelci, Eran

    2013-04-01

    Subaerial weathering of rocks is a common process observed on desert surfaces on Earth and other planetary terrestrial surfaces such as on Mars. On Earth, this weathering process has been previously identified as one of the key erosion agent driving geomorphic surface evolution and the development of desert pavements. And yet, fundamental aspects of the process, such as the relative contribution of the different weathering modes that drive it (e.g., mechanical breakdown of rocks, chemical weathering, aeolian abrasion and exfoliation) as well as the rate by which this weathering process occurs have not been systematically examined. Here, we present a new approach for quantitatively addressing these fundamental aspects of process geomorphology on desert surfaces. We focus here on co-genetic desert alluvial surfaces of different ages, i.e. alluvial chronosequences, which provide excellent recorders for the evolution of boulder-strewn surfaces into smooth desert pavements through in-situ subaerial weathering of rocks. Our approach combines independent measures of two different surface attributes: High resolution (mm-scale) 3D ground-based laser scanning (LiDAR) of surface micro-topography, and numerical dating of surface age. Roughness analysis of the LiDAR data in power spectral density (PSD) space allows us to characterize the geometric manifestation of rock weathering on the surface and to distinguish between the different weathering modes. Numerical age constraints provide independent estimates for the time elapsed since the process began. Accordingly, we are able to constrain surface roughness evolution on alluvial fan desert chronosequences through time, and present PSD analysis of surface roughness as a new quantitative tool to examine the process of subaerial rock weathering in desert environments. In this study we present results from two late Quaternary alluvial chronosequences along the Dead Sea Transform in the hyper-arid Negev desert of southern Israel. LiDAR scanning was applied on representative areas (~30-50 m2) of 10 separate surfaces ranging from rough Holocene surfaces to fairly smooth surfaces with well-developed pavements displaying an OSL age of 87 kyr. We find typical and recurring time-dependent changes in the offset as well as shape of the PSD curves in both chronosequences: PSD offset is continuously reduced over time reflecting the overall reduction in the amplitude of roughness at all wavelengths. The PSD curves display progressive moderation of slopes at the longer wavelengths with the moderation point itself systematically shifted to shorter wavelengths. This characteristic evolution of PSD offset and slope moderation at longer wavelengths reflects the typical break up of boulder-sized clasts through time as the surfaces mature into well-developed desert pavements and points towards mechanical breakdown as the dominant weathering mode. In addition, we are able to determine the rate by which the larger clasts are removed from the system. We build on these new insights into process and rate of rock weathering to propose PSD analysis of surface roughness as a complementary method for constraining the age of desert alluvial surfaces in places where 'conventional' dating cannot be applied.

  9. Novel natural and anthropogenic physical mechanisms of weather and climate changes

    NASA Astrophysics Data System (ADS)

    Voronin, Nikolai; Avakyan, Sergei

    2010-05-01

    A unified approach is suggested to the problem of impact of both space and several anthropogenic sources on the weather and climate changes. The united agent of this impact is examined i.e. microwave emission of the ionosphere, which resulted from ionospheric atoms and molecules excitation into highly excited (Rydberg) states by fast ionospheric electrons. Fast electrons with the energies more than 15 eV are formed with the photoionization of the upper atmosphere under the effect of X-ray/EUV solar radiation and with the ionization of the corpuscular precipitations from the radiation belts and magnetosphere both during of geomagnetic storms and under the anthropogenic influences. The latter (the work of powerful navigation and communication radio stations (because the most of them induce very low frequency (VLF) range: from few to few tens kilo Hertz.), electric power lines, starting space rockets, industrial activity) determines the locality of precipitations and accordingly the local action of the microwave radiation of the ionosphere on the weather characteristics. Surface transmitters with such frequency have power up to 1 Mw that cause precipitations and result in optical emission (the aurora of the class IBC II or more) above the transmitter. Indeed results of measurements performed by the satellites Intercosmos-Bulgaria 1300 at 1982 and DEMETER at 2005 confirm very high extent of disturbance of radiation belts and night ionosphere above the zone of work of VLF transmitters both in Northern Hemisphere (transmitters NLK, NAA in USA and UMS, RPS in Russia), and in Southern Hemisphere (transmitter NWC) especially during geomagnetic disturbances. Areas of stimulated electron precipitations and areas of perturbed ionosphere are linked either with the magnetic force line at which the surface VHL transmitter is situated or with the magnetic line at which effect of radio wave on the pitch angle of electron, captured in radiation belt, takes place. This area of stimulated perturbations reaches a half of million of square kilometers. Every time perturbations of lesser scale are observed in magnetic conjugate area. In accordance with our calculations the rate of ionization and excitation of ionosphere in the conjugate point and hence, generation of microwave radiation from Rydberg states reaches 10 % of the effect in the point of the transmitter work. We suggest three-stage radio-optical trigger mechanism for the ionospheric microwaves influence on the weather and climate. The first stage is an increase in generation of the microwave radiation which penetrates from the ionosphere to the earth surface. The second stage is a change in the proportion of water vapour to water clusters caused by increased microwave radiation. The third stage is a change of the atmosphere transparence in the absorption bands of water vapour and clusters. The atmosphere transparence due to cloudiness (usually optically thin (warming) clouds from solar flares and corpuscular of both natural and technological precipitations) determines fluxes of solar irradiance coming down as well as fluxes of the thermal radiation coming out from the underlying surface. The maximum of secular cycles of solar activity was observed in eighties of last century. Since 1985 the total solar irradiance and ionizing radiation fluxes have been decreasing but geomagnetic activity (aa - index) has been going up till 2003. Only during the last few years geomagnetic activity also started decreasing. This means that negative trends have begun both for solar and geomagnetic activities, and also there is a positive trend of GCR since 1998 which participate in generation of optically thick (cooling) clouds. We suppose that according to our mechanism the natural global warming will go down to lower levels.

  10. The Themis-Beagle families: Investigation of space-weathering processes on primitive surfaces

    NASA Astrophysics Data System (ADS)

    Fornasier, S.; Perna, D.; Lantz, C.; Barucci, M.

    2014-07-01

    In the past 20 years, enormous progress has been reached in the study of space-weathering (SW) effects on silicates and silicate asteroids. The so-called ordinary chondrite paradox, that is, lack of asteroids similar to the ordinary chondrites, which represent 80 % of meteorite falls, has been solved. These meteorites are now clearly related to S-type asteroids, as proved also by the direct measurements of the NEAR and HAYABUSA missions on the near-Earth asteroids Eros and Itokawa. Spectral differences between S-type asteroids and ordinary chondrites are caused by space-weathering effects, which produce a darkening in the albedo, a reddening of the spectra, and diminish the silicate absorption bands on the asteroids surfaces, exposed to cosmic radiation and solar wind. On the other hand, our understanding of space-weathering effects on primitive asteroids is still poor. Only few laboratory experiments have been devoted to the investigation of SW effects on dark carbonaceous chondrites and on complex organic materials. Irradiation of transparent organic materials produces firstly redder and darker materials that upon further processing turn flatter-bluish and darker (Kanuchova et al. 2012; Moroz et al. 2004). The Themis family is a natural laboratory to study primitive asteroids and space-weathering effects. The Themis family is located between 3.05 and 3.24 au, beyond the snow line, and it is composed of primitive asteroids. Themis is one of the most statistically reliable families in the asteroid belt. First discovered by Hirayama (1918), it has been identified as a family in all subsequent works, and it has 550 members as determined by Zappalà et al. (1995) and more than 4000 as determined by Nesvorny et al. (2010). The family formed probably about 2.3 Gyr ago as a result of a large-scale catastrophic disruption event of a parent asteroid 400 km in diameter colliding with a 190-km projectile (Marzari et al. 1995). Several Themis family members show absorption features associated to hydrated silicates, and, recently, water-ice and organics features have been detected on the surface of (24) Themis (Campins et al. 2010, Rivkin & Emery 2010). Hydrated silicates are produced by the aqueous-alteration process, which require low temperature (< 320 K) and the presence of liquid water in the past. The Themis family may be an important reservoir of water ice. Moreover, the main-belt comets 133P, 238P, and 176P seem to be related to the Themis family because of orbital proximities and spectral properties analogies. Within the old Themis family members, a young sub-family, Beagle, formed less than 10 Myr ago, has been identified. This sub-family has 65 members up to 2 km of diameter (Nesvorny et al. 2008). So, the Themis family is very important to shed light on the asteroid-comet continuum, to constrain the abundances of water ices in the outer part of the main belt, and to probe space-weathering effects on old Themis and young Beagle families' members. To investigate all these aspects, we carried out a spectroscopic survey in the visible and near-infrared range at the 3.6-m Italian telescope TNG (La Palma, Spain) during 6 nights in February and December 2012. We got new spectra of 8 Beagle and 22 Themis members using the DOLORES (with the LR-R and LR-B grisms) and the NICS (with the Amici prism) instruments. To look for possible coma around the targets, we also performed deep imaging in the R filter. Data are currently under analysis, and the results will be presented at the ACM meeting. None of the investigated spectra show water-ice absorption features at 1.5 and 2 microns, while few Themis members have visible absorption bands associated with hydrated silicates. The best meteoritic analogues to both Themis and Beagle members are the carbonaceous chondrites, especially CM2. The spectra of Beagle and Themis asteroids show significant differences: 'old' Themis members exhibit a wide range of spectra, including asteroids with blue/neutral and moderately red spectra (relative to the Sun), while the young Beagle members investigated are bluer and brighter than the Themis ones. These preliminary results seem to indicate that the SW effects on primitive asteroids are similar to those observed on silicate asteroids, that is, they produce reddening of the spectra and moderate darkening of the surface.

  11. Physical processes in laser-materials interactions

    SciTech Connect

    Bertolotti, M.

    1983-01-01

    This book explores the effects of laser light on metals and semiconductors as part of Plenum's NATO Advanced Study Institute Series. It presents papers by leading metallurgists, solid-state physicists, and other scientists employing laser technology who review the latest applications of the laser in metalworking, drilling, cutting, alloying, hardening, and semiconductor annealing. It provides detailed information on the physical processes involved in laser-materials interactions-coupling of laser radiation to metals and semiconductors, heating, and phase transformations. Considers the practical implications of these processes. It explores the thermodynamics of fast processes, a field originating in the laser treatment of materials, and includes information on the interaction of lasers with refractory materials and some general background data on laser-materials interactions.

  12. Clouds, weather, climate, and modeling for K-12 and public audiences from the Center for Multi-scale Modeling of Atmospheric Processes

    NASA Astrophysics Data System (ADS)

    Foster, S. Q.; Johnson, R. M.; Randall, D. A.; Denning, A.; Russell, R. M.; Gardiner, L. S.; Hatheway, B.; Jones, B.; Burt, M. A.; Genyuk, J.

    2010-12-01

    The need for improving the representation of cloud processes in climate models has been one of the most important limitations of the reliability of climate-change simulations. Now in its fifth year, the National Science Foundation-funded Center for Multi-scale Modeling of Atmospheric Processes (CMMAP) at Colorado State University (CSU) is addressing this problem through a revolutionary new approach to representing cloud processes on their native scales, including the cloud-scale interaction processes that are active in cloud systems. CMMAP has set ambitious education and human-resource goals to share basic information about the atmosphere, clouds, weather, climate, and modeling with diverse K-12 and public audiences. This is accomplished through collaborations in resource development and dissemination between CMMAP scientists, CSU’s Little Shop of Physics (LSOP) program, and the Windows to the Universe (W2U) program at University Corporation for Atmospheric Research (UCAR). Little Shop of Physics develops new hands on science activities demonstrating basic science concepts fundamental to understanding atmospheric characteristics, weather, and climate. Videos capture demonstrations of children completing these activities which are broadcast to school districts and public television programs. CMMAP and LSOP educators and scientists partner in teaching a summer professional development workshops for teachers at CSU with a semester's worth of college-level content on the basic physics of the atmosphere, weather, climate, climate modeling, and climate change, as well as dozens of LSOP inquiry-based activities suitable for use in classrooms. The W2U project complements these efforts by developing and broadly disseminating new CMMAP-related online content pages, animations, interactives, image galleries, scientists’ biographies, and LSOP videos to K-12 and public audiences. Reaching nearly 20 million users annually, W2U is highly valued as a curriculum enhancement resource, because its content is written at three levels in English and Spanish. Links between science topics and literature, art, and mythology enable teachers of English Language Learners, literacy, and the arts to integrate science into their classrooms. In summary, the CMMAP NSF-funded Science and Technology Center has established a highly effective and productive partnership of scientists and educators focused on enhancing public science literacy about weather, climate, and global change. All CMMAP, LSOP, and W2U resources can be accessed online at no cost by the entire atmospheric science K-12 and informal science education community.

  13. Hands-on, online, and workshop-based K-12 weather and climate education resources from the Center for Multi-scale Modeling of Atmospheric Processes

    NASA Astrophysics Data System (ADS)

    Foster, S. Q.; Johnson, R. M.; Randall, D. A.; Denning, A.; Burt, M. A.; Gardiner, L.; Genyuk, J.; Hatheway, B.; Jones, B.; La Grave, M. L.; Russell, R. M.

    2009-12-01

    The need for improving the representation of cloud processes in climate models has been one of the most important limitations of the reliability of climate-change simulations. Now in its fourth year, the National Science Foundation-funded Center for Multi-scale Modeling of Atmospheric Processes (CMMAP) at Colorado State University (CSU) is addressing this problem through a revolutionary new approach to representing cloud processes on their native scales, including the cloud-scale interaction processes that are active in cloud systems. CMMAP has set ambitious education and human-resource goals to share basic information about the atmosphere, clouds, weather, climate, and modeling with diverse K-12 and public audiences. This is accomplished through collaborations in resource development and dissemination between CMMAP scientists, CSU’s Little Shop of Physics (LSOP) program, and the Windows to the Universe (W2U) program at University Corporation for Atmospheric Research (UCAR). Little Shop of Physics develops new hands on science activities demonstrating basic science concepts fundamental to understanding atmospheric characteristics, weather, and climate. Videos capture demonstrations of children completing these activities which are broadcast to school districts and public television programs. CMMAP and LSOP educators and scientists partner in teaching a summer professional development workshops for teachers at CSU with a semester's worth of college-level content on the basic physics of the atmosphere, weather, climate, climate modeling, and climate change, as well as dozens of LSOP inquiry-based activities suitable for use in classrooms. The W2U project complements these efforts by developing and broadly disseminating new CMMAP-related online content pages, animations, interactives, image galleries, scientists’ biographies, and LSOP videos to K-12 and public audiences. Reaching nearly 20 million users annually, W2U is highly valued as a curriculum enhancement resource, because its content is written at three levels in English and Spanish. Links between science topics and literature, art, and mythology enable teachers of English Language Learners, literacy, and the arts to integrate science into their classrooms. In summary, the CMMAP NSF-funded Science and Technology Center has established a highly effective and productive partnership of scientists and educators focused on enhancing public science literacy about weather, climate, and global change. All CMMAP, LSOP, and W2U resources can be accessed online at no cost by the entire atmospheric science K-12 and informal science education community.

  14. Atomic-Scale Modeling and Theory of Space Weathering Processes: Mechanisms and Surface Properties

    NASA Astrophysics Data System (ADS)

    Schelling, P. K.; Britt, D. T.; Quadery, A. H.; Tucker, W. C.; Blair, R.

    2015-11-01

    We apply atomic-scale simulation to describe space weathering, including point-defect migration and surface properties. Distinct differences are reported between olivine and orthopyroxene. Surface properties including adhesion are described.

  15. Space Weather Prediction Using a Hybrid Physics/Black-box Model

    NASA Astrophysics Data System (ADS)

    Spencer, E. A.; Kaveri, S.; Horton, W.; Mays, L.

    2006-12-01

    A hybrid physics/black-box approach is used to model the nightside magnetosphere. The physics based model is a state-space description of the global energy components of the system called WINDMI. A nonlinear system identification technique using multi-resolution wavelet decomposition is developed that incorporates the physics model as part of a larger hybrid model. The input to the hybrid model is the solar wind velocity, Interplanetary Magnetic Field, and the proton density measured by the Advance Composition Explorer (ACE) satellite. The output of the combined model is the westward auroral index AL, and the equatorial storm time index Dst. The performance of the hybrid model is evaluated using historical geomagnetic storm datasets.

  16. Physics of a random biological process

    NASA Astrophysics Data System (ADS)

    Canessa, E.; Calmetta, A.

    1994-07-01

    We analyze the successive fluctuations of the daytime and nighttime sleep pattern of a newborn baby by using tools of far-from-equilibrium statistical physics. We find that this class of natural random biological process displays a remarkable long-range power-law correlation that extends for, at least, the first six months of life. Such a scaling behavior might help to characterize the underlying dynamics of the (early) growth and development of humans through analyzing the time series generated when asleep.

  17. Doing It In The SWMF Way: From Separate Space Physics Simulation Programs To The Framework For Space Weather Simulation.

    NASA Astrophysics Data System (ADS)

    Volberg, O.; Toth, G.; Sokolov, I.; Ridley, A. J.; Gombosi, T. I.; de Zeeuw, D. C.; Hansen, K. C.; Chesney, D. R.; Stout, Q. F.; Powell, K. G.; Kane, K. J.; Oehmke, R. C.

    2003-12-01

    The NASA-funded Space Weather Modeling Framework (SWMF) is developed to provide "plug and play" type Sun-to-Earth simulation capabilities serving the space physics modeling community. In its fully developed form, the SWMF will comprise a series of interoperating models of physics domains, ranging from the surface of the Sun to the upper atmosphere of the Earth. In its current form the SWMF links together five models: Global Magnetosphere, Inner Heliosphere, Ionosphere Electrodynamics, Upper Atmosphere, and Inner Magnetosphere. The framework permits to switch models of any type. The SWMF is a structured collection of software building blocks that can be used or customized to develop Sun-Earth system modeling components, and to assemble them into application. The SWMF consist of utilities and data structures for creating model components and coupling them. The SWMF contains Control Model, which controls initialization and execution of the components. It is responsible for component registration, processor layout for each component and coupling schedules. A component is created from the user-supplied physics code by adding a wrapper, which provides the control functions and coupling interface to perform the data exchange with other components. Both the wrapper and coupling interface are constructed from the building blocks provided by the framework itself. The current SWMF implementation is based on the latest component technology and uses many important concepts of Object-Oriented Programming emulated in Fortran 90. Currently it works on Linux Beowulf clusters, SGI Origin 2000 and Compaq ES45 machines.

  18. An advanced physical coal cleaning process

    SciTech Connect

    Wang, Z.; Zhu, S.; Jiang, Z.Y.; Fu, X.

    1994-12-31

    Physical processes for deep-cleaning of coal have been developed, the application of which depends to a large extent upon their economic feasibility; the determinate factors are the cost of ultra-fine grinding to attain necessary liberation of locked mineral from the coal matrix and the cost of reagents consumed to effect separation of micronized coal and mineral particles in aqueous suspension. Modified stirred ball mill has been found to be the promising equipment for ultra-fine coal grinding with both low energy and metal consumption. Selective flocculation-flotation process, as given in the paper presented at the last Conference, is technically feasible for preparation of ultra-clean coal. Recent work has indicated that the reagent consumption can be further reduced to a level proximating that in conventional coal flotation, being more economic feasible for its applications. Ultra-clean coals have been recovered by this process from conventional coal concentrate or low-ash raw coal. It can also be applied to process middling product from a coal preparation plant for additional concentrate extracted at very high yield. For metallurgical coal with difficult washability or high content of middling fractions, the advent of this process will be attractive in both technically and economically.

  19. Physical characteristics of welding arc ignition process

    NASA Astrophysics Data System (ADS)

    Shi, Linan; Song, Yonglun; Xiao, Tianjiao; Ran, Guowei

    2012-07-01

    The existing research of welding arc mainly focuses on the stable combustion state and the research on the mechanism of welding arc ignition process is quite lack. The tungsten inert gas(TIG) touch arc ignition process is observed via a high speed camera and the high time resolution spectral diagnosis system. The changing phenomenon of main ionized element provided the electrons in the arc ignition is found. The metallic element is the main contributor to provide the electrons at the beginning of the discharging, and then the excitated shielding gas element replaces the function of the metallic element. The electron density during the period of the arc ignition is calculated by the Stark-broadened lines of H?. Through the discussion with the repeatability in relaxation phenomenon, the statistical regularity in the arc ignition process is analyzed. The similar rules as above are observed through the comparison with the laser-assisted arc ignition experiments and the metal inert gas(MIG) arc ignition experiments. This research is helpful to further understanding on the generation mechanism of welding arc ignition and also has a certain academic and practical significance on enriching the welding physical theoretical foundation and improving the precise monitoring on automatic arc welding process.

  20. Displaying Composite and Archived Soundings in the Advanced Weather Interactive Processing System

    NASA Technical Reports Server (NTRS)

    Barrett, Joe H., III; Volkmer, Matthew R.; Blottman, Peter F.; Sharp, David W.

    2008-01-01

    In a previous task, the Applied Meteorology Unit (AMU) developed spatial and temporal climatologies of lightning occurrence based on eight atmospheric flow regimes. The AMU created climatological, or composite, soundings of wind speed and direction, temperature, and dew point temperature at four rawinsonde observation stations at Jacksonville, Tampa, Miami, and Cape Canaveral Air Force Station, for each of the eight flow regimes. The composite soundings were delivered to the National Weather Service (NWS) Melbourne (MLB) office for display using the National version of the Skew-T Hodograph analysis and Research Program (NSHARP) software program. The NWS MLB requested the AMU make the composite soundings available for display in the Advanced Weather Interactive Processing System (AWIPS), so they could be overlaid on current observed soundings. This will allow the forecasters to compare the current state of the atmosphere with climatology. This presentation describes how the AMU converted the composite soundings from NSHARP Archive format to Network Common Data Form (NetCDF) format, so that the soundings could be displayed in AWl PS. The NetCDF is a set of data formats, programming interfaces, and software libraries used to read and write scientific data files. In AWIPS, each meteorological data type, such as soundings or surface observations, has a unique NetCDF format. Each format is described by a NetCDF template file. Although NetCDF files are in binary format, they can be converted to a text format called network Common data form Description Language (CDL). A software utility called ncgen is used to create a NetCDF file from a CDL file, while the ncdump utility is used to create a CDL file from a NetCDF file. An AWIPS receives soundings in Binary Universal Form for the Representation of Meteorological data (BUFR) format (http://dss.ucar.edu/docs/formats/bufr/), and then decodes them into NetCDF format. Only two sounding files are generated in AWIPS per day. One file contains all of the soundings received worldwide between 0000 UTC and 1200 UTC, and the other includes all soundings between 1200 UTC and 0000 UTC. In order to add the composite soundings into AWIPS, a procedure was created to configure, or localize, AWIPS. This involved modifying and creating several configuration text files. A unique fourcharacter site identifier was created for each of the 32 soundings so each could be viewed separately. The first three characters were based on the site identifier of the observed sounding, while the last character was based on the flow regime. While researching the localization process for soundings, the AMU discovered a method of archiving soundings so old soundings would not get purged automatically by AWl PS. This method could provide an alternative way of localizing AWl PS for composite soundings. In addition, this would allow forecasters to use archived soundings in AWIPS for case studies. A test sounding file in NetCDF format was written in order to verify the correct format for soundings in AWIPS. After the file was viewed successfully in AWIPS, the AMU wrote a software program in the Tool Command Language/Tool Kit (Tcl/Tk) language to convert the 32 composite soundings from NSHARP Archive to CDL format. The ncgen utility was then used to convert the CDL file to a NetCDF file. The NetCDF file could then be read and displayed in AWIPS.

  1. Bringing life to soil physical processes

    NASA Astrophysics Data System (ADS)

    Hallett, P. D.

    2013-12-01

    When Oklahoma's native prairie grass roots were replaced by corn, the greatest environmental (and social) disaster ever to hit America ensued. The soils lost structure, physical binding by roots was annihilated and when drought came the Great Dust Bowl commenced. This form of environmental disaster has repeated over history and although not always apparent, similar processes drive the degradation of seemingly productive farmland and forests. But just as negative impacts on biology are deleterious to soil physical properties, positive impacts could reverse these trends. In finding solutions to soil sustainability and food security, we should be able to exploit biological processes to improve soil physical properties. This talk will focus on a quantitative understanding of how biology changes soil physical behaviour. Like the Great Dust Bowl, it starts with reinforcement mechanisms by plant roots. We found that binding of soil by cereal (barley) roots within 5 weeks of planting can more than double soil shear strength, with greater plant density causing greater reinforcement. With time, however, the relative impact of root reinforcement diminishes due to root turnover and aging of the seedbed. From mechanical tests of individual roots, reasonable predictions of reinforcement by tree roots are possible with fibre bundle models. With herbaceous plants like cereals, however, the same parameters (root strength, stiffness, size and distribution) result in a poor prediction. We found that root type, root age and abiotic factors such as compaction and waterlogging affect mechanical behaviour, further complicating the understanding and prediction of root reinforcement. For soil physical stability, the interface between root and soil is an extremely important zone in terms of resistance of roots to pull-out and rhizosphere formation. Compounds analogous to root exudates have been found with rheological tests to initially decrease the shear stress where wet soils flow, but after decomposition of these exudates by microbes the shear stress increases. This suggests an initial dispersion, followed by aggregation of the soil, which explains the structural arrangement of soil particles in the rhizosphere observed by microscopy. Dispersion of soil minerals in the root zone is important to release bound nutrients from mineral surfaces. Using fracture mechanics we measured large impacts of biological exudates on the toughness and interparticle bond energy of soils. Now novel tests are being developed to quantify interparticle bonding by biological exudates on single and multiple particle contacts, including mechanical test specimens that can be inoculated with specific bacteria or fungi. This will allow for clay mineralogy, water potential and solution chemistry impacts on interparticle bonding to be quantified directly. Wettability experiments with the same samples measure hydrological properties such as contact angle. Basic information from these tests will help explain biological processes that drive soil structure formation and stabilisation, providing data for models of soil structure dynamics.

  2. Cryptomelane: A tool to determine the age and the physical-chemical regime of a Plio-Pleistocene weathering zone in a granitic terrain (Hagendorf, SE Germany)

    NASA Astrophysics Data System (ADS)

    Dill, H. G.; Hansen, B.; Keck, E.; Weber, B.

    2010-09-01

    Cryptomelane, a K-Mn-bearing oxide, is widespread in the lowermost part of the weathering/supergene alteration zone of the Hagendorf Pegmatite, SE Germany. This supergene Mn mineral has been used in the present study for K/Ar dating of weathering and paleohydraulic processes as young as Plio-Pleistocene. Different cryptomelane age data found in the same weathering and paleohydraulic system resulted from continuous hydraulic processes in the weathering system rather than from a stepwise uplift that shaped the landscape in the granitic area of the NE Bavarian Basement. An almost pure cryptomelane mineralization is indicative of the basal zone of supergene alteration, because a complete separation of Mn from Fe can favorably be achieved only in the infiltration zone under slightly reducing conditions or in the percolation zone under slightly oxidizing conditions. Cryptomelane is precipitated under slightly oxidizing conditions from alkaline solutions in the percolation zone and cast as a marker for fluctuating (paleo)water levels. Manganese oxides, uranyl phosphates and silicates were found at different depths in the weathering zone of this granitic terrain. They were dated by different dating methods (K/Ar and U/Pb) and yielded the same age of formation. Consequently, the 4 Ma signal of both groups of supergene minerals has geomorphological and paleohydraulic connotation and is related to a unique geomorphological process, the Pliocene peneplanation. Gradual hydraulic adjustments gave rise to the younger Pleistocene age found at shallow depth in the weathering zone.

  3. Physical processes in collapse driven supernova

    SciTech Connect

    Mayle, R.W.

    1985-11-01

    A model of the supernova explosion is discussed. The method of neutrino transport is discussed, since the explosive mechanism depends on neutrino heating of the material behind the accretion shock. The core region of these exploding stars becomes unstable to convective motions during the supernova evolution. Convective mixing allows more neutrinos to escape from under the neutrinosphere, and thus increases the amount of heating by neutrinos. An approximate method of incorporating convection is described, and some results of including convection in a computer model is presented. Another phenomena is seen in computer simulations of supernova, oscillations in the neutrino luminosity and mass accretion rate onto the protoneutron star. The last topic discussed in this thesis describes the attempt to understand this oscillation by perturbation of the steady state solution to equations approximating the complex physical processes occurring in the late time supernova. 42 refs., 31 figs.

  4. Weather variability, ecological processes and optimization of soil micro-environment for rangeland restoration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Arid and semi-arid rangelands occupy over half of the earth’s surface and are characterized by relatively high variability in seasonal and annual patterns of precipitation. Invasive plants compete for soil and water resources and exacerbate inherent weather limitations for native plant establishmen...

  5. Contrasting Li and Mg isotope behaviour in small Alpine rivers: tracing seasonal changes in weathering processes (Invited)

    NASA Astrophysics Data System (ADS)

    Tipper, E.; Hindshaw, R. S.; Bourdon, B.; Lemarchand, E.

    2013-12-01

    Seasonal changes in river chemistry offer the potential to assess how weathering processes respond to changing meteorological parameters and ultimately how chemical weathering might respond to climatic parameters. A key observation with time-series data on river waters is that variations in elemental concentrations (typically less than an order of magnitude) are damped compared to variations in discharge (up to several orders of magnitude). This behavior is referred to as chemostatic. However, both radiogenic and stable isotope ratios of the solutes show significant, systematic temporal variations than indicate that there is not a chemostasis in the elemental release of solutes during dissolution. Here we discuss systematic seasonal variations in lithium and magnesium isotope ratios (the 7Li/6Li 26Mg/24Mg ratio expressed as delta7Li and delta26Mg in per mil units) in stream waters from a mono-lithological granitic, weathering-limited, first order catchment from the Swiss Alps (Damma glacier). Rain, ground, and pore-waters, in addition to plants, rocks, mineral separates and soil are also reported. Whilst the concentration response of Li and Mg in the river waters is attenuated compared to the large changes in discharge that occur over an annual cycle the systematic trends in both the Mg and Li isotope data imply that either the source of the Li and Mg changes in a systematic manner, or that the process by which Mg and Li are released into solution changes as a function of discharge. In the first order the Mg and Li isotope data appear to show similar trends. However, when examined in more detail, it is difficult to reconcile the data by one pair of fractionation factors for Li and Mg. This provides an additional constraint on how weathering processes vary over a seasonal cycle, and perhaps indications an incomplete equilibrium or kinetic limitation to weathering. The reasons behind these trends will be discussed in the context of the apparent chemostatic behavior of solute concentrations. Such isotopic observations provide significant insight into how solutes can apparently keep pace with order of magnitude variations in discharge, one of the key reasons why runoff is frequently identified as being a key variable in weathering fluxes.

  6. Weather Watch

    ERIC Educational Resources Information Center

    Bratt, Herschell Marvin

    1973-01-01

    Suggests a number of ways in which Federal Aviation Agency weather report printouts can be used in teaching the weather section of meteorology. These weather sequence reports can be obtained free of charge at most major airports. (JR)

  7. Physical processes in EUV sources for microlithography

    NASA Astrophysics Data System (ADS)

    Banine, V. Y.; Koshelev, K. N.; Swinkels, G. H. P. M.

    2011-06-01

    The source is an integral part of an extreme ultraviolet lithography (EUVL) tool. Such a source, as well as the EUVL tool, has to fulfil very high demands both technical and cost oriented. The EUVL tool operates at a wavelength of 13.5 nm, which requires the following new developments. The light production mechanism changes from conventional lamps and lasers to relatively high-temperature emitting plasmas. The light transport, mainly refractive for deep ultraviolet (DUV), should be reflective for EUV. The source specifications as derived from the customer requirements on wafer throughput mean that the output EUV source power has to be hundreds of watts. This in its turn means that tens to hundreds of kilowatts of dissipated power has to be managed in a relatively small volume. In order to keep lithography costs as low as possible, the lifetime of the components should be as long as possible and at least of the order of thousands of hours. This poses a challenge for the sources, namely how to design and manufacture components robust enough to withstand the intense environment of high heat dissipation, flows of several keV ions as well as the atomic and particular debris within the source vessel. As with all lithography tools, the imaging requirements demand a narrow illumination bandwidth. Absorption of materials at EUV wavelengths is extreme with extinguishing lengths of the order of tens of nanometres, so the balance between high transmission and spectral purity requires careful engineering. All together, EUV lithography sources present technological challenges in various fields of physics such as plasma, optics and material science. These challenges are being tackled by the source manufacturers and investigated extensively in the research facilities around the world. An overview of the published results on the topic as well as the analyses of the physical processes behind the proposed solutions will be presented in this paper.

  8. Physics as an Enterprise of Process Philosophy

    ERIC Educational Resources Information Center

    Rangacharyulu, Chary

    2005-01-01

    Physics, as a discipline, attempts to discern the mysteries of physical universe and it is also an inspiration for technological innovations which contribute to the good or demise of human civilization. While it continues to have tremendous impact on the technological front, one wonders if physics, as an enterprise engaged in providing a coherent

  9. The Stress Process in Physical Education

    ERIC Educational Resources Information Center

    Blankenship, Bonnie Tjeerdsma

    2007-01-01

    Negative stress in physical education can reduce a student's enjoyment of physical activity and destroy the individual's desire to be a lifelong mover. The purpose of this article is to explore the concept of stress in physical education. Stress is defined as a substantial imbalance between the demand of a situation and the individual's capability…

  10. A processing-modeling routine to use rough data from automatic weather stations in snowpack mass dynamics modeling at fine temporal resolutions

    NASA Astrophysics Data System (ADS)

    Avanzi, Francesco; De Michele, Carlo; Ghezzi, Antonio; Jommi, Cristina; Pepe, Monica

    2015-04-01

    We discuss a proposal of coupled routine to process rough data from automatic weather stations at an hourly resolution and to model snowpack mass dynamics. Seasonal snow represents an important component of the water cycle in mountain environment, and the modeling of its mass dynamics is a living topic in modern hydrology, given the expected modifications of the climate in the near future. Nevertheless, model forcing, calibration and evaluation operations are often hampered by the noisiness of rough data from automatic weather stations. The noise issue include, among others, non-physical temperature-based fluctuations of the signal or gauge under-catch. Consequently, it can be difficult to quantify precipitation inputs, accumulation/ablation periods or melt-runoff timing and amounts. This problem is particularly relevant at fine temporal resolution (e.g., the hourly one). To tackle this issue, 40 SNOTEL sites from western US are here considered, and the proposed processing-modeling routine is applied on multi-year datasets to assess its performances to both process hourly data and model snowpack dynamics. A simple one-layer snowpack model is used for this purpose. Specific attention is paid to remove sub-daily erroneous oscillations of snow depth. Under these assumptions, we can separate events of different types and recover catch deficiency by means of a data-fusion procedure that relies on the mass conservation law, instead of site- or instrument-specific relations. Since the considered model needs the calibration of two parameters, and given that sub-daily physical oscillations in snow depth data are difficult to be separated from instrument noise, a coupled processing-modeling procedure has been designed. Results prove that noise can be successfully removed from data, and that sub-daily data-series can be exploited as useful sources to model snowpack dynamics.

  11. Space Weathering of Asteroids: Issues Remain

    NASA Astrophysics Data System (ADS)

    Chapman, C. R.

    2003-05-01

    After decades of debate, consensus now exists that asteroid reflectance spectra are affected by space weathering. Based on a recent consensus [1] about the physical processes that space weather the Moon, we can realistically hypothesize about the causes of asteroidal space weathering and about how the processes might be manifested on different types of asteroids. But issues and questions remain. While vapor deposition on grains dominates lunar space weathering, for asteroids the relative vapor production by solar wind sputtering versus micrometeorite impact (or even other processes masked on the Moon) remains uncertain. Particularly troublesome are the different styles of space weathering on Ida and Eros; these otherwise similarly sized SIV asteroids differ mainly in being either in the belt or in near-Earth space, but how does that affect space weathering so dramatically? A vital issue is the timescale for space weathering to be manifested, or to mature, under various conditions (e.g. in or out of the belt, for different taxonomic types, or for different sizes). An extraordinary discovery may finally help provide an answer. Nesvorny et al. [2,3] have discovered how to date the creation of specific asteroids (i.e. in a catastrophic collisional break-up) with a robust precision of several percent, competitive with meteoritic age-dating techniques except that we know which specific asteroids the dates pertain to. The Karin cluster, within the S-type Koronis family, formed 5.8 +/-0.2 Myr ago. This age is of the order of estimates of space-weathering/regolith-evolution timescales. Spectral studies of Karin cluster members, and members of other dated families, may determine the absolute rates of space weathering processes. That in turn can elucidate the physical processes and permit better extrapolation to other asteroids. References: [1] B. Hapke (2001) J. Geophys. Res. 106, 10039-10073; [2] D. Nesvorny et al. (2002) Nature 417, 720-722; [3] D. Nesvorny et al. (2003) Astrophys. J. 591, 486-497.

  12. Weather-driven variation in dengue activity in Australia examined using a process-based modeling approach.

    PubMed

    Bannister-Tyrrell, Melanie; Williams, Craig; Ritchie, Scott A; Rau, Gina; Lindesay, Janette; Mercer, Geoff; Harley, David

    2013-01-01

    The impact of weather variation on dengue transmission in Cairns, Australia, was determined by applying a process-based dengue simulation model (DENSiM) that incorporated local meteorologic, entomologic, and demographic data. Analysis showed that inter-annual weather variation is one of the significant determinants of dengue outbreak receptivity. Cross-correlation analyses showed that DENSiM simulated epidemics of similar relative magnitude and timing to those historically recorded in reported dengue cases in Cairns during 1991-2009, (r = 0.372, P < 0.01). The DENSiM model can now be used to study the potential impacts of future climate change on dengue transmission. Understanding the impact of climate variation on the geographic range, seasonality, and magnitude of dengue transmission will enhance development of adaptation strategies to minimize future disease burden in Australia. PMID:23166197

  13. Space Weathering of Apollo 16 Sample 62255: Lunar Rocks as Witness Plates for Deciphering Regolith Formation Processes

    NASA Technical Reports Server (NTRS)

    Wentworth, S. J.; McKay, D. S.; Keller, L. P.

    2004-01-01

    Space weathering, or alteration that occurs at the surfaces of materials exposed directly to space, has been one of the primary areas of focus of lunar studies for the past several years. It is caused by processes such as micrometeorite impacts and solar wind bombardment, and effects can include microcraters, spall zones, and vapor deposits. Much of the recent work on space weathering has been concentrated on nanoscale features, especially the amorphous rims commonly found on individual lunar soil grains. The rims typically contain nanophase Fe metal globules, which, along with Fe metal globules in agglutinates, have a profound effect on optical properties of lunar soils. The nanophase metallic iron globules cause the characteristic optical changes (reddening and darkening) found in mature lunar soils.

  14. NASA's Advancements in Space-Based Spectrometry Lead to Improvements in Weather Prediction and Understanding of Climate Processes

    NASA Technical Reports Server (NTRS)

    Susskind, Joel

    2010-01-01

    AIRS is a precision state of the art High Spectral Resolution Multi-detector IR grating array spectrometer that was launched into a polar orbit on EOS Aqua in 2002. AIRS measures most of the infra-red spectrum with very low noise from 650/cm to 2660/cm with a resolving power of 2400 at a spatial resolution of 13 km. The objectives of AIRS were to perform accurate determination of atmospheric temperature and moisture profiles in up to 90% partial cloud cover conditions for the purpose of improving numerical weather prediction and understanding climate processes. AIRS data has also been used to determine accurate trace gas profiles. A brief overview of the retrieval methodology used to analyze AIRS observations under partial cloud cover will be presented and sample results will be shown from the weather and climate perspectives.

  15. The Themis-Beagle families: clues into space weathering processes on primitive asteroids

    NASA Astrophysics Data System (ADS)

    Fornasier, S.; Perna, D.; Lantz, C.; Barucci, M. A.

    2015-10-01

    The Themis family is a natural laboratory to study the asteroids-comets continuum and space weathering effects. Recently water ice and organics were detected on 24 Themis indicating that the Themis family may be an important reservoir of ice. Moreover, some main belt comets may be related with the Themis family because of orbital proximities and spectral properties analogies. Within the old Themis family members, a young sub-family, Beagle, formed less than 10 Myr ago, has been identified. Thus the Themis family is very important to shed light on the asteroid-comet continuum, to constrain the abundances of water ices in the outer part of the main belt, and to probe space weathering effects on old Themis and young Beagle families' members.

  16. Stellar Evolution Physics, Volume 1: Physical Processes in Stellar Interiors

    NASA Astrophysics Data System (ADS)

    Iben, Icko, Jr.

    This volumes describes the microscopic physics operating in stars and demonstrates how stars respond to the operation of this physics from formation through hydrogen-burning phases, up to the onset of helium burning. Intended for beginning graduate students and senior undergraduates with a good background in physics and mathematics, it describes with many numerical examples and illustrations the intricate interplay between the microscopic physics and the macroscopic responses of the stars. Considerable attention is paid to how numerical solutions are obtained. The volume examines the gravitationally contracting phases which carry a star from formation to the core hydrogen-burning main sequence, through the main sequence phase, through shell hydrogen-burning phases as a red giant, up to the onset of core helium burning. Particular emphasis is placed on the gravothermal responses of stars to nuclear transformations in the interior , energy loss by photons from the surface, and energy loss by neutrinos from the interior, responses which express the very essence of stellar evolution.

  17. Proton computed tomography from multiple physics processes

    NASA Astrophysics Data System (ADS)

    Bopp, C.; Colin, J.; Cussol, D.; Finck, Ch; Labalme, M.; Rousseau, M.; Brasse, D.

    2013-10-01

    Proton CT (pCT) nowadays aims at improving hadron therapy treatment planning by mapping the relative stopping power (RSP) of materials with respect to water. The RSP depends mainly on the electron density of the materials. The main information used is the energy of the protons. However, during a pCT acquisition, the spatial and angular deviation of each particle is recorded and the information about its transmission is implicitly available. The potential use of those observables in order to get information about the materials is being investigated. Monte Carlo simulations of protons sent into homogeneous materials were performed, and the influence of the chemical composition on the outputs was studied. A pCT acquisition of a head phantom scan was simulated. Brain lesions with the same electron density but different concentrations of oxygen were used to evaluate the different observables. Tomographic images from the different physics processes were reconstructed using a filtered back-projection algorithm. Preliminary results indicate that information is present in the reconstructed images of transmission and angular deviation that may help differentiate tissues. However, the statistical uncertainty on these observables generates further challenge in order to obtain an optimal reconstruction and extract the most pertinent information.

  18. Statistical physics of media processes: Mediaphysics

    NASA Astrophysics Data System (ADS)

    Kuznetsov, Dmitri V.; Mandel, Igor

    2007-04-01

    The processes of mass communications in complicated social or sociobiological systems such as marketing, economics, politics, animal populations, etc. as a subject for the special scientific subbranch-“mediaphysics”-are considered in its relation with sociophysics. A new statistical physics approach to analyze these phenomena is proposed. A keystone of the approach is an analysis of population distribution between two or many alternatives: brands, political affiliations, or opinions. Relative distances between a state of a “person's mind” and the alternatives are measures of propensity to buy (to affiliate, or to have a certain opinion). The distribution of population by those relative distances is time dependent and affected by external (economic, social, marketing, natural) and internal (influential propagation of opinions, “word of mouth”, etc.) factors, considered as fields. Specifically, the interaction and opinion-influence field can be generalized to incorporate important elements of Ising-spin-based sociophysical models and kinetic-equation ones. The distributions were described by a Schrödinger-type equation in terms of Green's functions. The developed approach has been applied to a real mass-media efficiency problem for a large company and generally demonstrated very good results despite low initial correlations of factors and the target variable.

  19. Anvil Forecast Tool in the Advanced Weather Interactive Processing System, Phase II

    NASA Technical Reports Server (NTRS)

    Barrett, Joe H., III

    2008-01-01

    Meteorologists from the 45th Weather Squadron (45 WS) and Spaceflight Meteorology Group have identified anvil forecasting as one of their most challenging tasks when predicting the probability of violations of the Lightning Launch Commit Criteria and Space Light Rules. As a result, the Applied Meteorology Unit (AMU) created a graphical overlay tool for the Meteorological Interactive Data Display Systems (MIDDS) to indicate the threat of thunderstorm anvil clouds, using either observed or model forecast winds as input.

  20. The weathering and transformation process of lead in China's shooting ranges.

    PubMed

    Li, Yeling; Zhu, Yongbing; Zhao, Sanping; Liu, Xiaodong

    2015-09-01

    Corroding steel-core bullets from three shooting ranges in different climate zones of China were collected. Multiple technical methods (EMPA, SEM, XRD, and ICP-OES) were applied to investigate the structure, morphology, and weathering product of this type of bullet in China to analyze the weathering mechanisms in different types of soils. A scanning electron microscope (SEM) was used to view the morphology and microstructure of corrosion layers. On the corroded lead layer surface, unevenness, micro cracks, and spallation were usually present. Around the micro cracks, many types of euhedral and subhedral crystals of the secondary products of lead were formed, most of which were composed of cerussite (PbCO3), while hydrocerussite (Pb3(CO3)2(OH)2) was predominant in the bullet collected from the humid environment. X-ray power diffraction (XRD) results show that the secondary weathering products in the three shooting range soils are clearly different. In the Fangyan shooting range, which has a neutral and semi-arid soil, the lead weathering product was mainly hydrocerussite (Pb3(CO3)2(OH)2), while no substantial amount of crystal phase of lead compound could be found in acidic, damp soils from the Fenghuang shooting range, possibly due to the enhanced dissolution and mobilization of lead compounds at lower pH and higher content of organic matter in the soil. In hot and arid environment of the Baicheng shooting range, cerussite might have undergone thermal decomposition, thus generating shannonite (Pb2O(CO3)). These results indicate that the formation of secondary Pb minerals is largely affected by the climatic zone or the soil properties, which may have implications for range management practices. PMID:26283517

  1. Factoring in weather variation to capture the influence of urban design and built environment on globally recommended levels of moderate to vigorous physical activity in children

    PubMed Central

    Katapally, Tarun Reddy; Muhajarine, Nazeem

    2015-01-01

    Objectives In curbing physical inactivity, as behavioural interventions directed at individuals have not produced a population-level change, an ecological perspective called active living research has gained prominence. However, active living research consistently underexplores the role played by a perennial phenomenon encompassing all other environmental exposures—variation in weather. After factoring in weather variation, this study investigated the influence of diverse environmental exposures (including urban design and built environment) on the accumulation of globally recommended moderate to vigorous physical activity levels (MVPA) in children. Design This cross-sectional observational study is part of an active living initiative set in the Canadian prairie city of Saskatoon. As part of this study, Saskatoon's neighbourhoods were classified based on urban street design into grid-pattern, fractured grid-pattern and curvilinear types of neighbourhoods. Moreover, diverse environmental exposures were measured including, neighbourhood built environment, and neighbourhood and household socioeconomic environment. Actical accelerometers were deployed between April and June 2010 (spring-summer) to derive MVPA of 331 10–14-year-old children in 25 1-week cycles. Each cycle of accelerometry was conducted on a different cohort of children within the total sample and matched with weather data obtained from Environment Canada. Multilevel modelling using Hierarchical Linear and Non-linear Modelling software was conducted by factoring in weather variation to depict the influence of diverse environmental exposures on the accumulation of recommended MVPA. Results Urban design, including diversity of destinations within neighbourhoods played a significant role in the accumulation of MVPA. After factoring in weather variation, it was observed that children living in neighbourhoods closer to the city centre (with higher diversity of destinations) were more likely to accumulate recommended MVPA. Conclusions The findings indicate that after factoring in weather variation, certain types of urban design are more likely to be associated with MVPA accumulation. PMID:26621516

  2. Research in Support of Operational Space Weather Forecasting

    NASA Astrophysics Data System (ADS)

    Viereck, R. A.

    2014-12-01

    Space Weather Operations can be defined as the specification and forecasting of the space environment for societal benefit. It is the potential benefit to society that is the justification for much space physics research and it helps to highlight the importance of the NASA Sun Earth Connections and Heliophysics programs. Scientific advances in the last few years have brought the first physics-base space weather forecast model into operations. Observations of the sun at higher cadences and improved spectral and temporal resolution have opened new windows on the processes that drive space weather. However, there are still some fundamental scientific questions, relevant to space weather forecasting, the answers to which still elude us. In this presentation I will review some of the most pressing needs of the space weather forecasters and the scientific advances and new observations that would greatly enhance the accuracy of space weather products and predictions.

  3. Severe Weather

    ERIC Educational Resources Information Center

    Forde, Evan B.

    2004-01-01

    Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. This month's insert, Severe Weather, has been created by NOAA to help educate the public about hazardous weather conditions. The four types of severe weather highlighted in this poster are hurricanes,…

  4. Severe Weather

    ERIC Educational Resources Information Center

    Forde, Evan B.

    2004-01-01

    Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. This article deals with a poster entitled, "Severe Weather," that has been created by NOAA to help educate the public about hazardous weather conditions. The four types of severe weather highlighted in…

  5. Severe Weather

    ERIC Educational Resources Information Center

    Forde, Evan B.

    2004-01-01

    Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. This article deals with a poster entitled, "Severe Weather," that has been created by NOAA to help educate the public about hazardous weather conditions. The four types of severe weather highlighted in

  6. Severe Weather

    ERIC Educational Resources Information Center

    Forde, Evan B.

    2004-01-01

    Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. This month's insert, Severe Weather, has been created by NOAA to help educate the public about hazardous weather conditions. The four types of severe weather highlighted in this poster are hurricanes,

  7. Creating Interactive Graphical Overlays in the Advanced Weather Interactive Processing System (AWIPS) Using Shapefiles and DGM Files

    NASA Technical Reports Server (NTRS)

    Barrett, Joe H., III; Lafosse, Richard; Hood, Doris; Hoeth, Brian

    2007-01-01

    Graphical overlays can be created in real-time in the Advanced Weather Interactive Processing System (AWIPS) using shapefiles or DARE Graphics Metafile (DGM) files. This presentation describes how to create graphical overlays on-the-fly for AWIPS, by using two examples of AWIPS applications that were created by the Applied Meteorology Unit (AMU). The first example is the Anvil Threat Corridor Forecast Tool, which produces a shapefile that depicts a graphical threat corridor of the forecast movement of thunderstorm anvil clouds, based on the observed or forecast upper-level winds. This tool is used by the Spaceflight Meteorology Group (SMG) and 45th Weather Squadron (45 WS) to analyze the threat of natural or space vehicle-triggered lightning over a location. The second example is a launch and landing trajectory tool that produces a DGM file that plots the ground track of space vehicles during launch or landing. The trajectory tool can be used by SMG and the 45 WS forecasters to analyze weather radar imagery along a launch or landing trajectory. Advantages of both file types will be listed.

  8. Sr isotopes as a tracer of weathering processes and dust inputs in a tropical granitoid watershed, Luquillo Mountains, Puerto Rico

    NASA Astrophysics Data System (ADS)

    Pett-Ridge, Julie C.; Derry, Louis A.; Kurtz, Andrew C.

    2009-01-01

    Sr isotope data from soils, water, and atmospheric inputs in a small tropical granitoid watershed in the Luquillo Mountains of Puerto Rico constrain soil mineral development, weathering fluxes, and atmospheric deposition. This study provides new information on pedogenic processes and geochemical fluxes that is not apparent in watershed mass balances based on major elements alone. 87Sr/ 86Sr data reveal that Saharan mineral aerosol dust contributes significantly to atmospheric inputs. Watershed-scale Sr isotope mass balance calculations indicate that the dust deposition flux for the watershed is 2100 700 mg cm -2 ka -1. Nd isotope analyses of soil and saprolite samples provide independent evidence for the presence of Saharan dust in the regolith. Watershed-scale Sr isotope mass balance calculations are used to calculate the overall short-term chemical denudation velocity for the watershed, which agrees well with previous denudation rate estimates based on major element chemistry and cosmogenic nuclides. The dissolved streamwater Sr flux is dominated by weathering of plagioclase and hornblende and partial weathering of biotite in the saprock zone. A steep gradient in regolith porewater 87Sr/ 86Sr ratio with depth, from 0.70635 to as high as 0.71395, reflects the transition from primary mineral-derived Sr to a combination of residual biotite-derived Sr and atmospherically-derived Sr near the surface, and allows multiple origins of kaolinite to be identified.

  9. Thermodynamics of Irreversible Processes. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    ERIC Educational Resources Information Center

    Levin, Michael; Gallucci, V. F.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module describes the application of irreversible thermodynamics to biology. It begins with…

  10. Generation of abnormal trace element abundances in Antarctic eucrites by weathering processes

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Lindstrom, Marilyn M.

    1991-01-01

    Data were obtained on the trace- and major-element compositions of 16 Antarctic abnormal eucrites, many of which exhibiting positive (but sometimes negative) Ce anomalies, positive Eu anomalies, and low abundances of the remainder of the REEs. The results of data analysis suggest that the unusual REE patterns of abnormal Antarctic eucrites arise from weathering effects generated in or on the Antarctic ice. The suggested scenario involves the formation of melt water and its equilibration with the atmosphere, promoting the dissolution of REE-rich phosphates and the oxidation of Ce. As a result, tetravalent Ce is fractionated from the trivalent REE in solution.

  11. Probing new physics in rare charm processes

    SciTech Connect

    Hewett, J.L.

    1994-09-01

    The possibility of using the charm system to search for new physics is addressed. Phenomena such as D{sup 0} - {bar D}{sup 0} mixing and rare decays of charmed mesons are first examined in the Standard Model to test the present understanding and to serve as benchmarks for signals from new sources. The effects of new physics from various classes of non-standard dynamical models on D{sup 0} - {bar D}{sup 0} mixing are investigated.

  12. Weather & Weather Maps. Teacher's Manual.

    ERIC Educational Resources Information Center

    Metro, Peter M.; Green, Rachel E.

    This guide is intended to provide an opportunity for students to work with weather symbols used for reporting weather. Also included are exercises in location of United States cities by latitude and longitude, measurement of distances in miles and kilometers, and prediction of weather associated with various types of weather fronts. (RE)

  13. Enabling Effective Space Weather and Climatology (SWaC) Capabilities: The NRC Decadal Survey in Solar and Space Physics

    NASA Astrophysics Data System (ADS)

    Baker, D. N.

    2012-12-01

    The U.S. very much needs long-term observations of the space weather environment and must support the development and application of coupled space weather models to protect critical societal infrastructure, including communication, navigation, and terrestrial weather satellites. As just one example, solar and space physicists partnering with power grid engineers have created the capability to model the effects of geomagnetically-induced currents on electricity transmission and distribution systems. This crucially important work has produced sophisticated software to assess the response of the electrical power system to geomagnetic storms, to assess the vulnerabilities, and to develop mitigation strategies. To fulfill the requirements for space weather presented in the June 2010 U.S. National Space Policy and envisioned in the 2010 National Space Weather Program Plan, we must develop a new approach. The National Research Council's 2013-2022 Decadal Survey presents a vision for renewed national commitment to a comprehensive program in Space Weather and Climatology, building on agency strengths. Enabling an effective SWaC capability will require action across multiple agencies. To coordinate the development of this plan, the National Space Weather Program should be re-chartered under the auspices of the National Science and Technology Council and include active participation from the Office of Science and Technology Policy and the Office of Management and Budget. The plan should take into account current agency efforts and capabilities, leverage the new capabilities and knowledge that will arise from implementation of the Decadal Survey, and develop additional monitoring capabilities and platforms specifically tailored to space weather monitoring and prediction.

  14. Weathering in a Cup.

    ERIC Educational Resources Information Center

    Stadum, Carol J.

    1991-01-01

    Two easy student activities that demonstrate physical weathering by expansion are described. The first demonstrates ice wedging and the second root wedging. A list of the needed materials, procedure, and observations are included. (KR)

  15. Neutron radiography and X-ray computed tomography for quantifying weathering and water uptake processes inside porous limestone used as building material

    SciTech Connect

    Dewanckele, J.; De Kock, T.; Fronteau, G.; Derluyn, H.; Vontobel, P.; Dierick, M.; Van Hoorebeke, L.; Jacobs, P.; Cnudde, V.

    2014-02-15

    Euville and Savonnières limestones were weathered by acid test and this resulted in the formation of a gypsum crust. In order to characterize the crystallization pattern and the evolution of the pore structure below the crust, a combination of high resolution X-ray computed tomography and SEM–EDS was used. A time lapse sequence of the changing pore structure in both stones was obtained and afterwards quantified by using image analysis. The difference in weathering of both stones by the same process could be explained by the underlying microstructure and texture. Because water and moisture play a crucial role in the weathering processes, water uptake in weathered and non-weathered samples was characterized based on neutron radiography. In this way the water uptake was both visualized and quantified in function of the height of the sample and in function of time. In general, the formation of a gypsum crust on limestone slows down the initial water uptake in the materials. - Highlights: • Time lapse sequence in 3D of changing pore structures inside limestone • A combination of X-ray CT, SEM and neutron radiography was used. • Quantification of water content in function of time, height and weathering • Characterization of weathering processes due to gypsum crystallization.

  16. Characterization and nultivariate analysis of physical properties of processing peaches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Characterization of physical properties of fruits represents the first vital step to ensure optimal performance of fruit processing operations and is also a prerequisite in the development of new processing equipment. In this study, physical properties of engineering significance to processing of th...

  17. Geochemical evidence of chemical and physical weathering of mine waste downriver from the New Idria Mercury Mine, San Benito County, California

    NASA Astrophysics Data System (ADS)

    Sharma, R. K.; Weinman, B.

    2014-12-01

    Soil, river bank, and sediment samples were collected from Panoache Creek's mine tailings and its drainages in the Mendota Pool area of California's Central Valley. The samples were collected in order to understand the transport mechanisms of mercury and other heavy metals from the abandoned New Idria Mercury Mine (NIMM) in San Banito County, CA. It is generally thought that materials weathered from the NIMM site flow down gradient into the San Carlos Creek, which then joins Silver Creek and Panoche Creek, before finally ending up in the Valley's Mendota pool and San Joaquin River (SJR). While we know that factors like geology, anthropogenic activities, and weathering can accelerate heavy metal accumulation at downgradient reaches (Chakravarty and Patgiri, 2009), it is unclear how this part of the SJR has responded to the mine's abandonment since the 1970s. To investigate how mercury and other heavy metals are weathering and being transported through this portion of the SJR drainage, gains and losses using "enrichment factors" (EF) were calculated and compared along a gradient downstream. Overall, EF of fine and bank sediments show Hg is being enriched and stored within bank sediments. For example, Hg in banks sediments are up to 5% enriched compared to the bed sediments. There is also an enrichment gain trending downstream, as sediments settling in the Mendota pool have comparatively higher EF for Hg (0.94 ppm to 6.91 ppm) relative to background concentrations. Along with other geochemical indices, which can be used to more highly resolve exactly how mine contaminants like Hg are chemically and physically being weathered, (i.e., Igeo, PLI, and CIA) the overall enrichment trend is interpreted to be the physical transport of erosion material during runoff events from the stream banks of SJR tributaries. This interpretation is also supported by depleted Sr and enriched Rb/Sr ratios, which further support physical transport as a dominating factor in contaminant enrichment along the banks of the catchment area. Combined with general trends of increasing Igeo, PLI values, and generally low CIA indices, results support Hg weathering predominantly being controlled by a combination of physical weathering, anthropogenic activities, and bank erosion, that lead to Hg mobilization and transport to downstream areas.

  18. Verifying the learning process in physics

    NASA Astrophysics Data System (ADS)

    Tartaglia, A.; Tresso, E.

    2001-05-01

    This paper describes an automated evaluation system for the learning of general physics. The system whose name is Test on Line (ToL) is based on a question bank from which an appropriate software generates individual multi-issue questionnaires to be submitted through the Web. ToL has been extensively tested over three years and is presently in use for basic physics courses at the Engineering Faculties of the Turin Politecnico. The results of the experimentation and use are presented and discussed. Accumulating data allows for an optimization of the internal partitions of the question bank and of the selection criteria for generating of the questionnaires. The instrument proved to be useful and reliable and could become the core of an agreed common standard for physics education at university level.

  19. CHEMICAL AND PHYSICAL PROCESS AND MECHANISM MODELING

    EPA Science Inventory

    The goal of this task is to develop and test chemical and physical mechanisms for use in the chemical transport models of EPA's Models-3. The target model for this research is the Community Multiscale Air Quality (CMAQ) model. These mechanisms include gas and aqueous phase ph...

  20. Wide variability in physical activity environments and weather-related outdoor play policies in child-care centers within a single county of Ohio

    PubMed Central

    Copeland, Kristen A; Sherman, Susan N; Khoury, Jane C; Foster, Karla E; Saelens, Brian E; Kalkwarf, Heidi J

    2011-01-01

    Objectives To examine the variability of physical activity environments and outdoor play-policies in child-care centers, and to determine if they are associated with center demographic characteristics Design Telephone surveythe Early Learning Environments Physical Activity and Nutrition Telephone Survey (ELEPhANTS) Setting Child-care centers in Hamilton County (Cincinnati area), Ohio, 20089. Participants Directors of all 185 licensed full-time child-care centers in Hamilton County. Outcome Measures Descriptive measures of center playground and indoor physical activity environments, and weather-related outdoor-play policies. Results 162 (88%) centers responded. Most (93%) centers reported an on-site playground, but only half reported their playgrounds as large, at least 1/3rd covered in shade, or having a variety of portable play equipment. Only half reported having a dedicated indoor gross-motor room where children could be active during inclement weather. Only 20% of centers allowed children to go outside in temperatures below 32F, and 43% of centers reported allowing children outdoors during light rain. A higher percent of children receiving tuition-assistance was associated with lower quality physical activity facilities and stricter weather-related practices. National accreditation was associated with more physical-activity promoting practices. Conclusion We found considerable variability in the indoor and outdoor playground offerings among child-care centers, even within a single county of Ohio. Per center policy and limited inside options, childrens active opportunities are curtailed due to sub-freezing temperatures or light rain. Policy change and parent/teacher education may be needed to ensure children achieve ample opportunity for daily physical activity. PMID:21199969

  1. Coral-rubble ridges as dynamic coastal features - short-term reworking and weathering processes

    NASA Astrophysics Data System (ADS)

    Spiske, Michaela

    2016-02-01

    A coral-rubble ridge built by storm waves at Anegada (British Virgin Islands) underwent remarkable changes in shape and weathering in a 23-month period. The ridge is located along the island's north shore, in the lee of a fringing reef and a reef flat. This coarse-clast ridge showed two major changes between March 2013, when first examined, and February 2015, when revisited. First, a trench dug in 2013, and intentionally left open for further examination, was found almost completely infilled in 2015, and the ridge morphology was modified by slumping of clasts down the slope and by reworking attributable to minor storm waves. In size, composition and overall condition, most of the clasts that filled the trench resemble reworked clasts from the ridge itself; only a small portion had been newly brought ashore. Second, a dark gray patina formed on the whitish exteriors of the carbonate clasts that had been excavated in 2013. These biologically weathered, darkened clasts had become indistinguishable from clasts that had been at the ridge surface for a much longer time. The findings have two broader implications. First, coastal coarse-clast ridges respond not solely to major storms, but also to tropical storms or minor hurricanes. The modification and reworking of the ridge on Anegada most probably resulted from hurricane Gonzalo which was at category 1-2 as it passed about 60 km north of the island in October 2014. Second, staining of calcareous clasts by cyanobacteria in the supralittoral zone occurs within a few months. In this setting, the degree of darkening quickly saturates as a measure of exposure age.

  2. Alteration processes in volcanic soils and identification of exobiologically important weathering products on Mars using remote sensing.

    PubMed

    Bishop, J L; Froschl, H; Mancinelli, R L

    1998-12-25

    Determining the mineralogy of the Martian surface material provides information about the past and present environments on Mars which are an integral aspect of whether or not Mars was suitable for the origin of life. Mineral identification on Mars will most likely be achieved through visible-infrared remote sensing in combination with other analyses on landed missions. Therefore, understanding the visible and infrared spectral properties of terrestrial samples formed via processes similar to those thought to have occurred on Mars is essential to this effort and will facilitate site selection for future exobiology missions to Mars. Visible to infrared reflectance spectra are presented here for the fine-grained fractions of altered tephra/lava from the Haleakala summit basin on Maui, the Tarawera volcanic complex on the northern island of New Zealand, and the Greek Santorini island group. These samples exhibit a range of chemical and mineralogical compositions, where the primary minerals typically include plagioclase, pyroxene, hematite, and magnetite. The kind and abundance of weathering products varied substantially for these three sites due, in part, to the climate and weathering environment. The moist environments at Santorini and Tarawera are more consistent with postulated past environments on Mars, while the dry climate at the top of Haleakala is more consistent with the current Martian environment. Weathering of these tephra is evaluated by assessing changes in the leachable and immobile elements, and through detection of phyllosilicates and iron oxide/oxyhydroxide minerals. Identifying regions on Mars where phyllosilicates and many kinds of iron oxides/oxyhydroxides are present would imply the presence of water during alteration of the surface material. Tephra samples altered in the vicinity of cinder cones and steam vents contain higher abundances of phyllosilicates, iron oxides, and sulfates and may be interesting sites for exobiology. PMID:11542259

  3. Terrestrial-marine teleconnections in the Devonian: links between the evolution of land plants, weathering processes, and marine anoxic events

    PubMed Central

    Algeo, T. J.

    1998-01-01

    The Devonian Period was characterized by major changes in both the terrestrial biosphere, e.g. the evolution of trees and seed plants and the appearance of multi-storied forests, and in the marine biosphere, e.g. an extended biotic crisis that decimated tropical marine benthos, especially the stromatoporoid-tabulate coral reef community. Teleconnections between these terrestrial and marine events are poorly understood, but a key may lie in the role of soils as a geochemical interface between the lithosphere and atmosphere/hydrosphere, and the role of land plants in mediating weathering processes at this interface. The effectiveness of terrestrial floras in weathering was significantly enhanced as a consequence of increases in the size and geographic extent of vascular land plants during the Devonian. In this regard, the most important palaeobotanical innovations were (1) arborescence (tree stature), which increased maximum depths of root penetration and rhizoturbation, and (2) the seed habit, which freed land plants from reproductive dependence on moist lowland habitats and allowed colonization of drier upland and primary successional areas. These developments resulted in a transient intensification of pedogenesis (soil formation) and to large increases in the thickness and areal extent of soils. Enhanced chemical weathering may have led to increased riverine nutrient fluxes that promoted development of eutrophic conditions in epicontinental seaways, resulting in algal blooms, widespread bottomwater anoxia, and high sedimentary organic carbon fluxes. Long-term effects included drawdown of atmospheric pCO2 and global cooling, leading to a brief Late Devonian glaciation, which set the stage for icehouse conditions during the Permo-Carboniferous. This model provides a framework for understanding links between early land plant evolution and coeval marine anoxic and biotic events, but further testing of Devonian terrestrial-marine teleconnections is needed.

  4. Soil mineralogy at the Mars Exploration Rover landing sites: An assessment of the competing roles of physical sorting and chemical weathering

    NASA Astrophysics Data System (ADS)

    McGlynn, Ian O.; Fedo, Christopher M.; McSween, Harry Y., Jr.

    2012-01-01

    Soils in Gusev Crater and Meridiani Planum derive primarily from a surface dominated by basalt. The modal mineralogy of primary (igneous) and secondary (alteration) phases in the soils is estimated using Mssbauer, MiniTES, and APXS spectra. Primary minerals include plagioclase, pyroxene, and olivine with less common apatite, magnetite, and chromite. Secondary phases are dominated by sulfates, and include nanophase oxides, chlorides, hematite, and are assumed to include amorphous silica and phyllosilicates. Most soil chemical compositions overlap with basalts indicating that despite the presence of a secondary component in the soils, they have not been significantly chemically weathered. We modeled the significance of olivine dissolution by acid-S by iteratively removing the molar FeOT + MgO component (olivine proxy) from the mean bulk compositions of the Gusev rock classes Adirondack, Algonquin, and Irvine until none remained. Regardless of modeling conditions, acid-S alteration cannot account for many soils in Gusev Crater that are either depleted or enriched in molar FeOT + MgO, although it is a process capable of explaining some soil compositions. Based on a rock and mineral mixing model, supports our hypothesis for soil formation that consists of surface comminution by impact gardening, followed by compositional modification by hydrodynamic sorting and admixing of secondary components, including phyllosilicates and sulfates. Such a physical process can produce the range of molar FeOT + MgO in soils by concentrating or depleting specific minerals. For example, dust and fine sands are enriched in molar FeOT + MgO relative to coarse sand, which suggests accumulation of more mafic phases in finer grain fractions.

  5. Space Weathering in the Inner Solar System

    NASA Technical Reports Server (NTRS)

    Noble, Sarah K.

    2010-01-01

    "Space weathering" is the term given to the cumulative effects incurred by surfaces which are exposed to the harsh environment of space. Lunar sample studies over the last decade or so have produced a clear picture of space weathering processes in the lunar environment. By combining laboratory and remote spectra with microanalytical methods (scanning and transmission electron microscopy), we have begun to unravel the various processes (irradiation, micrometeorite bombardment, etc) that contribute to space weathering and the physical and optical consequences of those processes on the Moon. Using the understanding gleaned from lunar samples, it is possible to extrapolate weathering processes to other airless bodies from which we have not yet returned samples (i.e. Mercury, asteroids). Through experiments which simulate various components of weathering, the expected differences in environment (impact rate, distance from Sun, presence of a magnetic field, reduced or enhanced gravity, etc) and composition (particularly iron content) can be explored to understand how space weathering will manifest on a given body.

  6. The Space Weather Reanalysis

    NASA Astrophysics Data System (ADS)

    Kihn, E. A.; Ridley, A. J.; Zhizhin, M.

    2002-12-01

    The objective of this project is to generate a complete 11 year space weather representation using physically consistent data-driven space weather models. The project will create a consistent, integrated historical record of the near Earth space environment by coupling observational data from space environmental monitoring systems archived at NGDC with data-driven, physically based numerical models. The resulting product will be an enhanced look at the space environment on consistent grids, time resolution, coordinate systems and containing key fields allowing an interested user to quickly and easily incorporate the impact of the near-Earth space climate in environmentally sensitive models. Currently there are no easily accessible long term climate archives available for the space-weather environment. Just as with terrestrial weather it is crucial to understand both daily weather forecasts as well as long term climate changes, so this project will demonstrate the ability to generate a meaningful and physically derived space weather climatology. The results of this project strongly support the DOD's Environmental Scenario Generator (ESG) project. The ESG project provides tools for intellegent data mining, classification and event detection which could be applied to a historical space-weather database. The two projects together provide a suite of tools for the user interested in modeling the effect of the near-earth space environment. We will present results and methodologies developed during the first two years of effort in the project.

  7. Electrical Storm Simulation to Improve the Learning Physics Process

    ERIC Educational Resources Information Center

    Martnez Muoz, Miriam; Jimnez Rodrguez, Mara Lourdes; Gutirrez de Mesa, Jos Antonio

    2013-01-01

    This work is part of a research project whose main objective is to understand the impact that the use of Information and Communication Technology (ICT) has on the teaching and learning process on the subject of Physics. We will show that, with the use of a storm simulator, physics students improve their learning process on one hand they understand

  8. A New Perspective on Surface Weather Maps

    ERIC Educational Resources Information Center

    Meyer, Steve

    2006-01-01

    A two-dimensional weather map is actually a physical representation of three-dimensional atmospheric conditions at a specific point in time. Abstract thinking is required to visualize this two-dimensional image in three-dimensional form. But once that visualization is accomplished, many of the meteorological concepts and processes conveyed by the

  9. A New Perspective on Surface Weather Maps

    ERIC Educational Resources Information Center

    Meyer, Steve

    2006-01-01

    A two-dimensional weather map is actually a physical representation of three-dimensional atmospheric conditions at a specific point in time. Abstract thinking is required to visualize this two-dimensional image in three-dimensional form. But once that visualization is accomplished, many of the meteorological concepts and processes conveyed by the…

  10. Humps and hollows: basalt weathering in low-latitude mountains

    NASA Astrophysics Data System (ADS)

    Knight, Jasper; Grab, Stefan

    2013-04-01

    Physical, chemical and biological weathering processes are significant contributors to landscape development in mountain blocks worldwide, and over long time scales, but the interplay between different weathering processes is uncertain. Jurassic-age basalt lava flows underlie the Drakensberg mountain range of eastern Lesotho, southern Africa (summits 3200-3400 m asl), and weathered bedrock is commonly exposed on flat plateau surfaces. Subaerial weathering throughout the Quaternary and Holocene has resulted in a range of weathering forms, some of which exploit pre-existing cooling fractures within the basalts, and some of which are independent of geological control. These forms include pseudokarst-style potholes, karren and other microforms. The geometry, chemistry of water contained within the potholes, seasonal presence of ice, sediment and organic residues all suggest that physical, chemical and biological weathering processes are significant at different times and in different ways in subaerial weathering. Moreover, it is also likely that these process-types show pronounced seasonal variability that means that the interplay between different processes is subtle. Aggregated rates of land surface denudation or geomorphic development of single landforms therefore hide this subtle interplay between different processes. Changes in mountain summit soil depth (through soil erosion), ecosystems and climate will change this balance between different processes, and will operate over different spatial and temporal scales.

  11. Space Weathering of Rocks

    NASA Technical Reports Server (NTRS)

    Noble, Sarah

    2011-01-01

    Space weathering discussions have generally centered around soils but exposed rocks will also incur the effects of weathering. On the Moon, rocks make up only a very small percentage of the exposed surface and areas where rocks are exposed, like central peaks, are often among the least space weathered regions we find in remote sensing data. However, our studies of weathered Ap 17 rocks 76015 and 76237 show that significant amounts of weathering products can build up on rock surfaces. Because rocks have much longer surface lifetimes than an individual soil grain, and thus record a longer history of exposure, we can study these products to gain a deeper perspective on the weathering process and better assess the relative impo!1ance of various weathering components on the Moon. In contrast to the lunar case, on small asteroids, like Itokowa, rocks make up a large fraction of the exposed surface. Results from the Hayabusa spacecraft at Itokowa suggest that while the low gravity does not allow for the development of a mature regolith, weathering patinas can and do develop on rock surfaces, in fact, the rocky surfaces were seen to be darker and appear spectrally more weathered than regions with finer materials. To explore how weathering of asteroidal rocks may differ from lunar, a set of ordinary chondrite meteorites (H, L, and LL) which have been subjected to artificial space weathering by nanopulse laser were examined by TEM. NpFe(sup 0) bearing glasses were ubiquitous in both the naturally-weathered lunar and the artificially-weathered meteorite samples.

  12. Weather impacts on space operations

    NASA Astrophysics Data System (ADS)

    Madura, J.; Boyd, B.; Bauman, W.; Wyse, N.; Adams, M.

    The efforts of the 45th Weather Squadron of the USAF to provide weather support to Patrick Air Force Base, Cape Canaveral Air Force Station, Eastern Range, and the Kennedy Space Center are discussed. Its weather support to space vehicles, particularly the Space Shuttle, includes resource protection, ground processing, launch, and Ferry Flight, as well as consultations to the Spaceflight Meteorology Group for landing forecasts. Attention is given to prelaunch processing weather, launch support weather, Shuttle launch commit criteria, and range safety weather restrictions. Upper level wind requirements are examined. The frequency of hourly surface observations with thunderstorms at the Shuttle landing facility, and lightning downtime at the Titan launch complexes are illustrated.

  13. Physical Modeling of Hydrologic Processes in South Central Texas

    NASA Astrophysics Data System (ADS)

    El Hassan, A.; Sharif, H.; Xie, H.; Terrance, J.; Mcclelland, J.

    2012-04-01

    Flood magnitude and recurrence modeling and analysis play an important role in water resources planning, management, and permitting. In both urban and rural situations, flood analysis is important to flood plain mapping and the development of best management practices for both environmental and engineering concerns. The majority of annual precipitation in South Texas results from extreme, large storm events, which produce flash floods (the number one cause of weather-related deaths in Texas). Surface geology such as such as Edward out crop faulting zone at Balcones escarpment has different properties than the classified soil; affect the soil parameters such as infiltration or hydraulic conductivity. This result in a very high infiltration and channel loss as a recharge component to the Edward aquifer from the surface runoff and rivers that are crossing the recharge zone, such as Nueces, San Antonio, Guadalupe and Colorado Rivers. Water quality is another issue in hydrological modeling, specifically in south central Texas. Water quality assessment is another issue on hydrological modeling in south central Texas. SWAT Soil and water assessment tool model is used for water quality assessment in San Antonio River basin since the rainfall runoff simulation is a necessity to derive the surface water quality process especially in the streams. With the advances in the Geographical information system (GIS) and instant precipitation products such as next generation radar (NEXRAD) and data acquisition for these products, the accuracy of the hydrological models has improved. Different hydrological models were used to evaluate the surface water and other hydrological cycle components in different watersheds in south central Texas through different events and their different causes and effects in these watersheds. Some of them are semi distributed and lumped models such as Soil and Water Assessment Tool (SWAT), Hydrologic Modeling System (HEC-HMS) and physically based distributed model Girded Surface Subsurface Hydrologic Assessment GSSHA taking the advances of GIS, NEXRAD product, remote sensing and other product such as gridded land use and soil map to achieve the highest accuracy of these models.

  14. World weather program

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A brief description of the Global Weather Experiment is presented. The world weather watch program plan is described and includes a global observing system, a global data processing system, a global telecommunication system, and a voluntary cooperation program. A summary of Federal Agency plans and programs to meet the challenges of international meteorology for the two year period, FY 1980-1981, is presented.

  15. Home Weatherization Visit

    ScienceCinema

    Chu, Steven

    2013-05-29

    Secretary Steven Chu visits a home that is in the process of being weatherized in Columbus, OH, along with Ohio Governor Ted Strickland and Columbus Mayor Michael Coleman. They discuss the benefits of weatherization and how funding from the recovery act is having a direct impact in communities across America.

  16. Foundations of Physical Theory, I: Force and Energy. Physical Processes in Terrestrial and Aquatic Ecosystems, Fundamentals.

    ERIC Educational Resources Information Center

    Pearson, Nolan E.

    This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module is one of two units on the foundations of physical theory and the

  17. Modelling weathering processes at the catchment scale: The WITCH numerical model

    NASA Astrophysics Data System (ADS)

    Goddris, Yves; Franois, Louis M.; Probst, Anne; Schott, Jacques; Moncoulon, David; Labat, David; Viville, Daniel

    2006-03-01

    A numerical model of chemical weathering in soil horizons and underlying bedrock (WITCH) has been coupled to a numerical model of water and carbon cycles in forest ecosystems (ASPECTS) to simulate the concentration of major species within the soil horizons and the stream of the Strengbach granitic watershed, located in the Vosges Mountains (France). For the first time, simulations of solute concentrations in soil layers and in the catchment river have been performed on a seasonal basis. The model is able to reproduce the concentrations of most major species within the soil horizons, as well as catching the first-order seasonal fluctuations of aqueous calcium, magnesium and silica concentrations. However, the WITCH model underestimates concentrations of Mg 2+ and silica at the spring of the catchment stream, and significantly underestimates Ca 2+ concentration. The deficit in calculated calcium can be compensated for by dissolution of trace apatite disseminated in the bedrock. However, the resulting increased Ca 2+ release yields important smectite precipitation in the deepest model layer (in contact with the bedrock) and subsequent removal of large amount of silica and magnesium from solution. In contrast, the model accurately accounts for the concentrations of major species (Ca, Mg and silica) measured in the catchment stream when precipitation of clay minerals is not allowed. The model underestimation of Mg 2+ and H 4SiO 4 concentrations when precipitation of well crystallized smectites is allowed strongly suggests that precipitation of well crystallized clay minerals is overestimated and that more soluble poorly crystallized and amorphous materials may be forming. In agreement with observations on other watersheds draining granitic rocks, this study indicates that highly soluble trace calcic phases control the aqueous calcium budget in the Strengbach watershed.

  18. The influence of regional urbanization and abnormal weather conditions on the processes of human climatic adaptation on mountain resorts

    NASA Astrophysics Data System (ADS)

    Artamonova, M.; Golitsyn, G.; Senik, I.; Safronov, A.; Babyakin, A.; Efimenko, N.; Povolotskaya, N.; Topuriya, D.; Chalaya, E.

    2012-04-01

    This work is a further development in the study of weather pathogenic index (WPI) and negative influence of urbanization processes on the state of people's health with adaptation disorder. This problem is socially significant. According to the data of the WHO, in the world there are from 20 to 45% of healthy people and from 40 to 80% of people with chronic diseases who suffer from the raised meteosensitivity. As a result of our researches of meteosensitivity of people during their short-duration on mountain resorts there were used negative adaptive reactions (NAR) under 26 routine tests, stress-reactions under L.H. Garkavi's hemogram, vegetative indices, tests of neuro-vascular reactivity, signs of imbalance of vegetative and neurohumoral regulation according to the data of biorhythm fractal analysis and sudden aggravations of diseases (SAD) as an indicator of negative climatic and urbanization influence. In 2010-2011 the Caucasian mountain resorts were having long periods of climatic anomalies, strengthening of anthropogenic emissions and forest fires when record-breaking high waves of NAR and SAD were noticed. There have also been specified indices ranks of weather pathogenicity from results of comparison of health characteristics with indicators of synoptico-dynamic processes according to Weather Research and Forecasting model (WRF); air ionization N+, N-, N+/N- spectra of aerosol particles (the size from 500 to 20000 nanometers) and concentrations of chemically active gases (O3, NO, NO2, ), volatile phytoorganic substances in the surface atmosphere, bactericidal characteristics of vegetation by criterion χ2 (not above 0,05). It has allowed us to develop new physiological optimum borders, norm and pessimum, to classify emergency ecologo-weather situations, to develop a new techniques of their forecasting and prevention of meteopathic reactions with meteosensitive patients (Method of treatment and the early (emergency) and planned prevention meteopatic reactions in patients with coronary heart disease, hypertension stage I-II syndrome disadaptative using the transcranial mezo diencephalic modulation / L.I.Zherlitsina, N.V. Efimenko, N.P. Povolotskaya, I.I. Velikanov. the Patent for the invention No.2422128, RU (11) 2 422 128 (13) C1 from 6/27/2011; Bull.13). We have observed that such anthropogenic characteristics as accumulation of aerosol with the size of particles 500-5000 nanometers in the lower atmosphere in the quantity more than 60 particles/sm3 (getting to alveoli); decrease in quantity of negative ions (N-) lower than 200 ions/sm3, high coefficient of ions unipolarity (N+/N-) - more than 4-6; mass concentration of aerosol more than 150 mkg/m3 and other modules of the environment can act as limited markers for the forecast of dangerous NAR, SAD and taking of urgent radical preventive measures. These techniques of medical weather forecast and meteo prevention can be used in other mountain regions of the world. The studies were performed by support of the Program "Basic Sciences for Medicine" and RFBR project No.10-05-01014_a.

  19. Physical processes at high field strengths

    SciTech Connect

    Rhodes, C.K.

    1986-01-01

    Measurements of the radiation produced by the high field interaction with the rare gases have revealed the presence of both copious harmonic production and fluorescence. The highest harmonic observed was the seventeenth (14.6 rm) in Ne, the shortest wavelength ever produced by that means. Strong fluorescence was seen in Ar, Kr, and Xe with the shortest wavelengths observed being below 10 nm. Furthermore, radiation from inner-shell excited configurations in Xe, specifically the 4d/sup 9/5s5p ..-->.. 4d/sup 10/5s manifold at approx. 17.7 nm, was detected. The behaviors of the rare gases with respect to multiquantum ionization, harmonic production, and fluorescence were found to be correlated so that the materials fell into two groups, He and Ne in one and Ar, Kr, and Xe in the other. These experimental findings, in alliance with other studies on inner-shell decay processes, give evidence for a role of atomic correlations in a direct nonlinear process of inner-shell excitation. It is expected that an understanding of these high-field processes will enable the generation of stimulated emission in the x-ray range. 59 refs., 6 figs., 5 tabs.

  20. Evaluating the effects of terrestrial ecosystems, climate and carbon dioxide on weathering over geological time: a global-scale process-based approach

    PubMed Central

    Taylor, Lyla L.; Banwart, Steve A.; Valdes, Paul J.; Leake, Jonathan R.; Beerling, David J.

    2012-01-01

    Global weathering of calcium and magnesium silicate rocks provides the long-term sink for atmospheric carbon dioxide (CO2) on a timescale of millions of years by causing precipitation of calcium carbonates on the seafloor. Catchment-scale field studies consistently indicate that vegetation increases silicate rock weathering, but incorporating the effects of trees and fungal symbionts into geochemical carbon cycle models has relied upon simple empirical scaling functions. Here, we describe the development and application of a process-based approach to deriving quantitative estimates of weathering by plant roots, associated symbiotic mycorrhizal fungi and climate. Our approach accounts for the influence of terrestrial primary productivity via nutrient uptake on soil chemistry and mineral weathering, driven by simulations using a dynamic global vegetation model coupled to an ocean–atmosphere general circulation model of the Earth's climate. The strategy is successfully validated against observations of weathering in watersheds around the world, indicating that it may have some utility when extrapolated into the past. When applied to a suite of six global simulations from 215 to 50 Ma, we find significantly larger effects over the past 220 Myr relative to the present day. Vegetation and mycorrhizal fungi enhanced climate-driven weathering by a factor of up to 2. Overall, we demonstrate a more realistic process-based treatment of plant fungal–geosphere interactions at the global scale, which constitutes a first step towards developing ‘next-generation’ geochemical models. PMID:22232768

  1. TIME SERIES ANALYSIS OF REMOTELY-SENSED TIR EMISSION: linking anomalies to physical processes

    NASA Astrophysics Data System (ADS)

    Pavlidou, E.; van der Meijde, M.; Hecker, C.; van der Werff, H.; Ettema, J.

    2013-12-01

    In the last 15 years, remote sensing has been evaluated for detecting thermal anomalies as precursor to earthquakes. Important issues that need yet to be tackled include definition of: (a) thermal anomaly, taking into account weather conditions, observation settings and ';natural' variability caused by background sources (b) the length of observations required for this purpose; and (c) the location of detected anomalies, which should be physically related to the tectonic activity. To determine whether thermal anomalies are statistical noise, mere meteorological conditions, or actual earthquake-related phenomena, we apply a novel approach. We use brightness temperature (top-of-atmosphere) data from thermal infrared imagery acquired at a hypertemporal (sub-hourly) interval, from geostationary weather satellites over multiple years. The length of the time series allows for analysis of meteorological effects (diurnal, seasonal or annual trends) and background variability, through the application of a combined spatial and temporal filter to distinguish extreme occurrences from trends. The definition of potential anomalies is based on statistical techniques, taking into account published (geo)physical characteristics of earthquake related thermal anomalies. We use synthetic data to test the performance of the proposed detection method and track potential factors affecting the results. Subsequently, we apply the method on original data from Iran and Turkey, in quiescent and earthquake-struck periods alike. We present our findings with main focus to assess resulting anomalies in relation to physical processes thereby considering: (a) meteorological effects, (b) the geographical, geological and environmental settings, and (c) physically realistic distances and potential physical relations with the activity of causative faults.

  2. Physical process which shapes Cassiopeia A

    NASA Astrophysics Data System (ADS)

    Braun, Robert; Gull, Stephen F.; Perley, Richard A.

    1987-06-01

    The Cassiopeia A nebula provides a special opportunity for improving our understanding of how massive stars explode. Its relative proximity (a distance of 2.9 kpc) makes it possible to study the source's structure and time evolution in sufficient detail. The authors have exploited the rapid time evolution of the source through a series of three high-resolution radio images spanning four years. These images have allowed them to recognize the previously unsuspected process which is in fact dominant in shaping the object. Tenuous clumps of intermediate velocity stellar ejecta are now continuously puncturing, from within, the decelerated shell swept up by the diffuse ejecta which once had the highest velocity.

  3. Human sperm rheotaxis: a passive physical process.

    PubMed

    Zhang, Zhuoran; Liu, Jun; Meriano, Jim; Ru, Changhai; Xie, Shaorong; Luo, Jun; Sun, Yu

    2016-01-01

    A long-standing question in natural reproduction is how mammalian sperm navigate inside female reproductive tract and finally reach the egg cell, or oocyte. Recently, fluid flow was proposed as a long-range guidance cue for sperm navigation. Coitus induces fluid flow from oviduct to uterus, and sperm align themselves against the flow direction and swim upstream, a phenomenon termed rheotaxis. Whether sperm rheotaxis is a passive process dominated by fluid mechanics, or sperm actively sense and adapt to fluid flow remains controversial. Here we report the first quantitative study of sperm flagellar motion during human sperm rheotaxis and provide direct evidence indicating that sperm rheotaxis is a passive process. Experimental results show that there is no significant difference in flagellar beating amplitude and asymmetry between rheotaxis-turning sperm and those sperm swimming freely in the absence of fluid flow. Additionally, fluorescence image tracking shows no Ca(2+) influx during sperm rheotaxis turning, further suggesting there is no active signal transduction during human sperm rheotaxis. PMID:27005727

  4. Human sperm rheotaxis: a passive physical process

    PubMed Central

    Zhang, Zhuoran; Liu, Jun; Meriano, Jim; Ru, Changhai; Xie, Shaorong; Luo, Jun; Sun, Yu

    2016-01-01

    A long-standing question in natural reproduction is how mammalian sperm navigate inside female reproductive tract and finally reach the egg cell, or oocyte. Recently, fluid flow was proposed as a long–range guidance cue for sperm navigation. Coitus induces fluid flow from oviduct to uterus, and sperm align themselves against the flow direction and swim upstream, a phenomenon termed rheotaxis. Whether sperm rheotaxis is a passive process dominated by fluid mechanics, or sperm actively sense and adapt to fluid flow remains controversial. Here we report the first quantitative study of sperm flagellar motion during human sperm rheotaxis and provide direct evidence indicating that sperm rheotaxis is a passive process. Experimental results show that there is no significant difference in flagellar beating amplitude and asymmetry between rheotaxis-turning sperm and those sperm swimming freely in the absence of fluid flow. Additionally, fluorescence image tracking shows no Ca2+ influx during sperm rheotaxis turning, further suggesting there is no active signal transduction during human sperm rheotaxis. PMID:27005727

  5. Biogenic catalysis in sulphide minerals' weathering processes and acid mine drainage genesis.

    PubMed

    Kušnierová, Mária; Praščáková, Mária; Nowak, Anna K; Gorazda, Katarzyna; Wzorek, Zbigniew

    2014-01-01

    Bioleaching and biogenesis are the main outputs from a large group of environmental processes participating in the natural material cycle, used in raw materials processing. Bio-oxidation reactions are the main basis for bioleaching procedures, often participating in parallel leaching processes. During the leaching processes of polycomponent sulphide substrates, the factor of process selection also plays an important role, being in direct relation to the electric properties and galvanic effect occurring between the individual components of the leaching substrate. This work gives a summary of the results of a research focused on the possibilities of using biotechnological procedures for treatment of Slovak sulphide ores. The object of the research is extraction of valuable metals, undesirable admixtures and degradation of crystal lattice of sulphides for subsequent chemical leaching processing of precious metals. The results of experiments on the existence of biogenic processes in situ on waste dumps from exploitation containing residual sulphides are also presented. The processes result in acid mine drainage water generation. These waters are strongly mineralised (over 48 g/L) and of low pH; that is why they are very caustic. The arsenic content (2.558 mg/L) in outflowing waters from old mines is high and over the limits set by the law. PMID:24445359

  6. Two-Photon Physics in Hadronic Processes

    SciTech Connect

    Carl Carlson; Marc Vanderhaeghen

    2007-11-01

    Two-photon exchange contributions to elastic electron-scattering are reviewed. The apparent discrepancy in the extraction of elastic nucleon form factors between unpolarized Rosenbluth and polarization transfer experiments is discussed, as well as the understanding of this puzzle in terms of two-photon exchange corrections. Calculations of such corrections both within partonic and hadronic frameworks are reviewed. In view of recent spin-dependent electron scattering data, the relation of the two-photon exchange process to the hyperfine splitting in hydrogen is critically examined. The imaginary part of the two-photon exchange amplitude as can be accessed from the beam normal spin asymmetry in elastic electron-nucleon scattering is reviewed. Further extensions and open issues in this field are outlined.

  7. Turbulence and Fluid Flow: Perspectives. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    ERIC Educational Resources Information Center

    Simpson, James R.

    This module is part of a series on Physical Processes in Terrestrial and Aquatic Ecosystems. The materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process.…

  8. Redistribution of uranium by physical processes during weathering and implications for radon production.

    PubMed

    Bottrell, S H

    1993-03-01

    Erosion of the Edale shales of Derbyshire during the Tertiary and Quaternary has resulted in sediment deposits in and on the underlying karstified limestones. Sorting during sedimentation has generated clay-rich sediments which are uranium enriched due to a clay association of uranium in the shales. Radon production in these sediments is at or close to equilibrium with their uranium content, and their fine grain-size ensures efficient radon release. Such sediments are therefore potent local sources of environmental radon. PMID:24198078

  9. Uranium and thorium isotopes in the rivers of the Amazonian basin: hydrology and weathering processes

    NASA Astrophysics Data System (ADS)

    Marques, Aguinaldo N., Jr.; Al-Gharib, Iyad; Bernat, Michel; Fernex, Franois

    2003-01-01

    Two expeditions (October 1989 and May 1992) were carried out to two points of the main Amazon River channel and four tributaries. The Solimes and Madeira rivers, taking their origin in the Andes, are whitewater rivers. The Negro River is a typical acid, blackwater river. The Trombetas River flows through bauxite-rich areas, and is characterized by low concentrations of dissolved humic substances. The 238U, 234U, 232Th and 230Th activities were recorded from dissolved, suspended particulate phases and river bank sediments. The latter were analysed for their 226Ra, 228Ra and 210Pb contents, and also subjected to leaching with 02 M hydroxylamine-hydrochloride solution to determine the concentrations of radionuclides bound to amorphous Fe hydroxides and Mn oxides and hydroxides.The dissolved U average concentration in the Amazon system is ten times lower than the mean world river concentration. The uranium concentration observed at bidos in the lower Amazon (0095 g L-1), where the U content in the river bank sediments and suspended matter is lowest, suggests U release from the solid phase during river transport. About 485 t of U are transported annually to the Amazon delta area in dissolved form, and 1943 t bound to suspended particulate matter.Total U and Th concentrations in the river bank sediments ranged from 159 to 714 g g-1 and from 674 to 32 g g-1, respectively. The highest concentrations were observed in the Trombetas River. The proportion extracted by means of the hydroxylamine solution (HL) was relatively high for U in the Trombetas river bank sediment (31%) and for Th in the Solimes sediment (30%).1, but were <1 in the Negro River (at Manaus). The activity ratios of dissolved U correlate with pH and also with the U activity ratios in the river bank sediment hydroxylamine extracts. As expected, the 1 in the Trombetas and Negro rivers. Such ratios probably result from the binding of dissolved uranium to solid sediment.weathering rate of rocks in the Amazon system, which was estimated to be 27 cm 1000 year

  10. Cockpit weather information needs

    NASA Technical Reports Server (NTRS)

    Scanlon, Charles H.

    1992-01-01

    The primary objective is to develop an advanced pilot weather interface for the flight deck and to measure its utilization and effectiveness in pilot reroute decision processes, weather situation awareness, and weather monitoring. Identical graphical weather displays for the dispatcher, air traffic control (ATC), and pilot crew should also enhance the dialogue capabilities for reroute decisions. By utilizing a broadcast data link for surface observations, forecasts, radar summaries, lightning strikes, and weather alerts, onboard weather computing facilities construct graphical displays, historical weather displays, color textual displays, and other tools to assist the pilot crew. Since the weather data is continually being received and stored by the airborne system, the pilot crew has instantaneous access to the latest information. This information is color coded to distinguish degrees of category for surface observations, ceiling and visibilities, and ground radar summaries. Automatic weather monitoring and pilot crew alerting is accomplished by the airborne computing facilities. When a new weather information is received, the displays are instantaneously changed to reflect the new information. Also, when a new surface or special observation for the intended destination is received, the pilot crew is informed so that information can be studied at the pilot's discretion. The pilot crew is also immediately alerted when a severe weather notice, AIRMET or SIGMET, is received. The cockpit weather display shares a multicolor eight inch cathode ray tube and overlaid touch panel with a pilot crew data link interface. Touch sensitive buttons and areas are used for pilot selection of graphical and data link displays. Time critical ATC messages are presented in a small window that overlays other displays so that immediate pilot alerting and action can be taken. Predeparture and reroute clearances are displayed on the graphical weather system so pilot review of weather along the route can be accomplished prior to pilot acceptance of the clearance. An ongoing multiphase test series is planned for testing and modifying the graphical weather system. Preliminary data shows that the nine test subjects considered the graphical presentation to be much better than their current weather information source for situation awareness, flight safety, and reroute decision making.

  11. Space Weather: Where Is The Beef?

    NASA Astrophysics Data System (ADS)

    Koskinen, H. E. J.

    Space weather has become a highly fashionable topic in solar-terrestrial physics. It is perhaps the best tool to popularise the field and it has contributed significantly to the dialogue between solar, magnetospheric, and ionospheric scientist, and also to mu- tual understanding between science and engineering communities. While these are laudable achievements, it is important for the integrity of scientific space weather re- search to recognise the central open questions in the physics of space weather and the progress toward solving them. We still lack sufficient understanding of the solar physics to be able to tell in advance when and where a solar eruption will take place and whether it will turn to a geoeffective event. There is much to do to understand ac- celeration of solar energetic particles and propagation of solar mass ejecta toward the Earth. After more than 40 years of research scientific discussion of energy and plasma transfer through the magnetopause still deals mostly with qualitative issues and the rapid acceleration processes in the magnetosphere are not yet explained in a satisfac- tory way. Also the coupling to the ionosphere and from there to the strong induction effects on ground is another complex of research problems. For space weather science the beef is in the investigation of these and related topics, not in marketing half-useful space weather products to hesitant customers.

  12. Distributed System of Processing of Data of Physical Experiments

    NASA Astrophysics Data System (ADS)

    Nazarov, A. A.; Moiseev, A. N.

    2014-11-01

    Complication of physical experiments and increasing volumes of experimental data necessitate the application of supercomputer and distributed computing systems for data processing. Design and development of such systems, their mathematical modeling, and investigation of their characteristics and functional capabilities is an urgent scientific and practical problem. In the present work, the characteristics of operation of such distributed system of processing of data of physical experiments are investigated using the apparatus of theory of queuing networks.

  13. Enhancing Cloud Radiative Processes and Radiation Efficiency in the Advanced Research Weather Research and Forecasting (WRF) Model

    SciTech Connect

    Iacono, Michael J.

    2015-03-09

    The objective of this research has been to evaluate and implement enhancements to the computational performance of the RRTMG radiative transfer option in the Advanced Research version of the Weather Research and Forecasting (WRF) model. Efficiency is as essential as accuracy for effective numerical weather prediction, and radiative transfer is a relatively time-consuming component of dynamical models, taking up to 30-50 percent of the total model simulation time. To address this concern, this research has implemented and tested a version of RRTMG that utilizes graphics processing unit (GPU) technology (hereinafter RRTMGPU) to greatly improve its computational performance; thereby permitting either more frequent simulation of radiative effects or other model enhancements. During the early stages of this project the development of RRTMGPU was completed at AER under separate NASA funding to accelerate the code for use in the Goddard Space Flight Center (GSFC) Goddard Earth Observing System GEOS-5 global model. It should be noted that this final report describes results related to the funded portion of the originally proposed work concerning the acceleration of RRTMG with GPUs in WRF. As a k-distribution model, RRTMG is especially well suited to this modification due to its relatively large internal pseudo-spectral (g-point) dimension that, when combined with the horizontal grid vector in the dynamical model, can take great advantage of the GPU capability. Thorough testing under several model configurations has been performed to ensure that RRTMGPU improves WRF model run time while having no significant impact on calculated radiative fluxes and heating rates or on dynamical model fields relative to the RRTMG radiation. The RRTMGPU codes have been provided to NCAR for possible application to the next public release of the WRF forecast model.

  14. DOE Workshop; Pan-Gass Conference on the Representation of Atmospheric Processes in Weather and Climate Models

    SciTech Connect

    Morrison, PI Hugh

    2012-09-21

    This is the first meeting of the whole new GEWEX (Global Energy and Water Cycle Experiment) Atmospheric System Study (GASS) project that has been formed from the merger of the GEWEX Cloud System Study (GCSS) Project and the GEWEX Atmospheric Boundary Layer Studies (GABLS). As such, this meeting will play a major role in energizing GEWEX work in the area of atmospheric parameterizations of clouds, convection, stable boundary layers, and aerosol-cloud interactions for the numerical models used for weather and climate projections at both global and regional scales. The representation of these processes in models is crucial to GEWEX goals of improved prediction of the energy and water cycles at both weather and climate timescales. This proposal seeks funds to be used to cover incidental and travel expenses for U.S.-based graduate students and early career scientists (i.e., within 5 years of receiving their highest degree). We anticipate using DOE funding to support 5-10 people. We will advertise the availability of these funds by providing a box to check for interested participants on the online workshop registration form. We will also send a note to our participants' mailing lists reminding them that the funds are available and asking senior scientists to encourage their more junior colleagues to participate. All meeting participants are encouraged to submit abstracts for oral or poster presentations. The science organizing committee (see below) will base funding decisions on the relevance and quality of these abstracts, with preference given to under-represented populations (especially women and minorities) and to early career scientists being actively mentored at the meeting (e.g. students or postdocs attending the meeting with their advisor).

  15. Frost weathering versus glacial grinding in the micromorphology of quartz sand grains: Processes and geological implications

    NASA Astrophysics Data System (ADS)

    Woronko, Barbara

    2016-04-01

    Micromorphology of quartz sand grains is used to reconstruct processes occurring in the glacial environment and to distinguish the latter from other environments. Two processes dominate in the glacial environment, i.e., crushing and abrasion, or a combination thereof. Their effect is a wide range of microstructures on the surface of quartz grains, e.g., chattermarks, conchoidal fractures and multiple grooves. However, the periglacial environment also effectively modifies the surface of quartz grains. The active layer of permafrost is considered to have a significantly higher contribution to the formation of crushed grains and the number of microstructures resulting from mechanical destruction (e.g., breakage blocks or conchoidal fractures), as compared to deposits which are not affected by freeze-thaw cycles. However, only a few microstructures are found in both environments. At the same time, there are several processes in subglacial environments related to freeze-thaw cycles, e.g., regelation, congelation, basal adfreezing, and glaciohydraulic supercooling. Most likely, therefore, the role of the glacial environment in the destruction of quartz grains has been misinterpreted, and consequently the conclusions regarding environmental processes drawn on the basis of the number of crushed grains and edge-to-edge contacts are erroneous.

  16. NATURAL ARSENIC CONTAMINATION OF HOLOCENE ALLUVIAL AQUIFERS BY LINKED TECTONIC, WEATHERING, AND MICROBIAL PROCESSES

    EPA Science Inventory

    Linked tectonic, geochemical, and biologic processes lead to natural arsenic contamination of groundwater in Holocene alluvial aquifers, which are the main threat to human health around the world. These groundwaters are commonly found a long distance from their ultimate source of...

  17. Extrapolation of space weathering processes to other small solar system bodies

    NASA Technical Reports Server (NTRS)

    Gaffey, M. J.

    1993-01-01

    A diverse range of processes were invoked as the dominant factor or as important contributory factors in the modification of the optical surface and regolith of the moon. These include impact vitrification by large and small projectiles, solar wind implantation and the reduction of oxidized iron during energetic events, sputtering and crystal lattice damage by energetic cosmic rays, shock metamorphism of minerals, mixing of diverse lithologies by impacts, and contamination by external materials. These processes are also potentially important on the rocky surfaces of other small solar system bodies. For icy bodies, several additional processes are also possible, including formation of complex organic compounds from methane and ammonia-bearing ices by ultraviolet irradiation and the condensation of vapor species to form frost layers in the polar or cooler regions of objects at appropriate heliocentric distances. The lunar case, even when completely understood, will not extend in a simple linear fashion to other small rocky objects, nor will the optical surfaces of those objects all be affected to the same degree by each process. The major factors that will control the relative efficacy of a possible mechanism include the efficiency of ejecta retention and the degree to which the regolith materials experience multiple events (primarily a function of body size, escape velocity, and impactor velocities); the mean duration of typical regolith particle exposure at the optical surface and within reach of the micrometeorite, cosmic ray, solar wind, or UV fluxes (a function of the rate and scale of regolith mixing, production, and removal processes); the incident flux of solar (low energy) cosmic rays, solar wind, or UV radiation (inverse square of heliocentric distance) or of galactic (high energy) cosmic rays (slowly increasing flux with heliocentric distance); and the compositional and mineralogical nature of the surface being affected. In general, those processes that depend upon either the retention of impact ejecta or on the presence of multigenerational regoliths should be substantially less effective on smaller bodies with lower escape velocities. However, there are important exceptions to this generalization. For example, a process that involves the hypervelocity impact of small particles into a fine-grained regolith may be able to effectively retain highly shocked or melted material due to the nature of shock wave propagation in such a heterogeneous material.

  18. Extrapolation of space weathering processes to other small solar system bodies

    NASA Astrophysics Data System (ADS)

    Gaffey, M. J.

    A diverse range of processes were invoked as the dominant factor or as important contributory factors in the modification of the optical surface and regolith of the moon. These include impact vitrification by large and small projectiles, solar wind implantation and the reduction of oxidized iron during energetic events, sputtering and crystal lattice damage by energetic cosmic rays, shock metamorphism of minerals, mixing of diverse lithologies by impacts, and contamination by external materials. These processes are also potentially important on the rocky surfaces of other small solar system bodies. For icy bodies, several additional processes are also possible, including formation of complex organic compounds from methane and ammonia-bearing ices by ultraviolet irradiation and the condensation of vapor species to form frost layers in the polar or cooler regions of objects at appropriate heliocentric distances. The lunar case, even when completely understood, will not extend in a simple linear fashion to other small rocky objects, nor will the optical surfaces of those objects all be affected to the same degree by each process. The major factors that will control the relative efficacy of a possible mechanism include the efficiency of ejecta retention and the degree to which the regolith materials experience multiple events (primarily a function of body size, escape velocity, and impactor velocities); the mean duration of typical regolith particle exposure at the optical surface and within reach of the micrometeorite, cosmic ray, solar wind, or UV fluxes (a function of the rate and scale of regolith mixing, production, and removal processes); the incident flux of solar (low energy) cosmic rays, solar wind, or UV radiation (inverse square of heliocentric distance) or of galactic (high energy) cosmic rays (slowly increasing flux with heliocentric distance); and the compositional and mineralogical nature of the surface being affected. In general, those processes that depend upon either the retention of impact ejecta or on the presence of multigenerational regoliths should be substantially less effective on smaller bodies with lower escape velocities. However, there are important exceptions to this generalization. For example, a process that involves the hypervelocity impact of small particles into a fine-grained regolith may be able to effectively retain highly shocked or melted material due to the nature of shock wave propagation in such a heterogeneous material.

  19. Physical Processes in the MAGO/MFT Systems

    SciTech Connect

    Garanin, Sergey F; Reinovsky, Robert E.

    2015-03-23

    The Monograph is devoted to theoretical discussion of the physical effects, which are most significant for the alternative approach to the problem of controlled thermonuclear fusion (CTF): the MAGO/MTF approach. The book includes the description of the approach, its difference from the major CTF systems—magnetic confinement and inertial confinement systems. General physical methods of the processes simulation in this approach are considered, including plasma transport phenomena and radiation, and the theory of transverse collisionless shock waves, the surface discharges theory, important for such kind of research. Different flows and magneto-hydrodynamic plasma instabilities occurring in the frames of this approach are also considered. In virtue of the general physical essence of the considered phenomena the presented results are applicable to a wide range of plasma physics and hydrodynamics processes. The book is intended for the plasma physics and hydrodynamics specialists, post-graduate students, and senior students-physicists.

  20. Weather Instruments.

    ERIC Educational Resources Information Center

    Brantley, L. Reed, Sr.; Demanche, Edna L.; Klemm, E. Barbara; Kyselka, Will; Phillips, Edwin A.; Pottenger, Francis M.; Yamamoto, Karen N.; Young, Donald B.

    This booklet presents some activities to measure various weather phenomena. Directions for constructing a weather station are included. Instruments including rain gauges, thermometers, wind vanes, wind speed devices, humidity devices, barometers, atmospheric observations, a dustfall jar, sticky-tape can, detection of gases in the air, and pH of

  1. Wacky Weather

    ERIC Educational Resources Information Center

    Sabarre, Amy; Gulino, Jacqueline

    2013-01-01

    What do a leaf blower, water hose, fan, and ice cubes have in common? Ask the students who participated in an integrative science, technology, engineering, and mathematics (I-STEM) education unit, "Wacky Weather," and they will tell say "fun and severe weather"--words one might not have expected! The purpose of the unit…

  2. Weather Instruments.

    ERIC Educational Resources Information Center

    Brantley, L. Reed, Sr.; Demanche, Edna L.; Klemm, E. Barbara; Kyselka, Will; Phillips, Edwin A.; Pottenger, Francis M.; Yamamoto, Karen N.; Young, Donald B.

    This booklet presents some activities to measure various weather phenomena. Directions for constructing a weather station are included. Instruments including rain gauges, thermometers, wind vanes, wind speed devices, humidity devices, barometers, atmospheric observations, a dustfall jar, sticky-tape can, detection of gases in the air, and pH of…

  3. Wacky Weather

    ERIC Educational Resources Information Center

    Sabarre, Amy; Gulino, Jacqueline

    2013-01-01

    What do a leaf blower, water hose, fan, and ice cubes have in common? Ask the students who participated in an integrative science, technology, engineering, and mathematics (I-STEM) education unit, "Wacky Weather," and they will tell say "fun and severe weather"--words one might not have expected! The purpose of the unit

  4. AN overview of the FLYSAFE datalink solution for the exchange of weather information: supporting aircrew decision making processes.

    NASA Astrophysics Data System (ADS)

    Mirza, A.; Drouin, A.

    2009-09-01

    FLYSAFE is an Integrated Project of the 6th framework of the European Commission with the aim to improve flight safety through the development of an avionics solution the Next Generation Integrated Surveillance System (NGISS), which is supported by a ground based network of Weather Information Management Systems (WIMS) and access points in the form of the Ground Weather Processor (GWP). The NGISS provides information to the flight crew on the three major external hazards for aviation: weather, air traffic and terrain. The NGISS has the capability of displaying data about all three hazards on a single display screen, facilitating rapid appreciation of the situation by the flight crew. Weather Information Management Systems (WIMS) were developed to provide the NGISS and the flight crew with weather related information on in-flight icing, thunderstorms and clear-air turbulence. These products are generated on the ground from observations and model forecasts. WIMS will supply relevant information on three different scales: global, regional and local (over airport Terminal Manoeuvring Area). The Ground Weather Processor is a client-server architecture that utilises open source components, which include a geospatial database and web feature services. The GWP stores Weather Objects generated by the WIMS. An aviation user can retrieve on-demand all Weather Objects that intersect the volume of space that is of interest to them. The Weather Objects are fused with in-situ observation data and can be used by the flight management system to propose a route to avoid the hazard. In addition they can be used to display the current hazardous weather to the Flight Crew thereby raising their awareness. Within the FLYSAFE program, around 120 hours of flight trials were performed during February 2008 and August 2008. Two aircraft were involved each with separate objectives: - to assess FLYSAFE's innovative solutions for the data-link, on-board data-fusion and data-display and data-updates during flight; - to evaluate the new weather information management systems (in-flight icing and thunderstorms) using in-situ measurements recorded on-board the test aircraft. In this presentation we will focus on the data link solution to uplink the Weather Objects to the NGISS. As part of the solution, a brief description is given on how grid data created by the WIMS are transformed to Weather Objects; which describe the weather hazard and are formatted using the Geospatial Mark-up Language.

  5. Ontology of physics for biology: representing physical dependencies as a basis for biological processes

    PubMed Central

    2013-01-01

    Background In prior work, we presented the Ontology of Physics for Biology (OPB) as a computational ontology for use in the annotation and representations of biophysical knowledge encoded in repositories of physics-based biosimulation models. We introduced OPB:Physical entity and OPB:Physical property classes that extend available spatiotemporal representations of physical entities and processes to explicitly represent the thermodynamics and dynamics of physiological processes. Our utilitarian, long-term aim is to develop computational tools for creating and querying formalized physiological knowledge for use by multiscale physiome projects such as the EUs Virtual Physiological Human (VPH) and NIHs Virtual Physiological Rat (VPR). Results Here we describe the OPB:Physical dependency taxonomy of classes that represent of the laws of classical physics that are the rules by which physical properties of physical entities change during occurrences of physical processes. For example, the fluid analog of Ohms law (as for electric currents) is used to describe how a blood flow rate depends on a blood pressure gradient. Hookes law (as in elastic deformations of springs) is used to describe how an increase in vascular volume increases blood pressure. We classify such dependencies according to the flow, transformation, and storage of thermodynamic energy that occurs during processes governed by the dependencies. Conclusions We have developed the OPB and annotation methods to represent the meaningthe biophysical semanticsof the mathematical statements of physiological analysis and the biophysical content of models and datasets. Here we describe and discuss our approach to an ontological representation of physical laws (as dependencies) and properties as encoded for the mathematical analysis of biophysical processes. PMID:24295137

  6. Genesis of karren in Kentucky Lake, Tennessee: Interaction of geologic structure, weathering processes, and bioerosion

    SciTech Connect

    Gibson, M.A.; Smith, W.L. )

    1993-03-01

    While karst features formed along marine coastlines are commonly reported, shoreline karst features produced within lacustrine systems have received little attention. The shoreline of Bond Island'' in Kentucky Lake has evolved a distinctive karren geomorphology not recognized elsewhere in the lake. The karren consist of well-developed clint and grike topography, trench formation, solution pits, flutes, and runnels, and pit and tunnel development. Two processes are responsible for the karren. First, freshwater dissolution and wave action on structurally fractured Decatur Limestone (Silurian) mechanically and chemically weaken the entire exposed surface. Second, a seasonal cycle of winter freeze-thaw and frost wedging followed by spring bioerosion overprints the first set of processes. Bioerosion by chemical dissolution involving a complex association of predominantly chironomids, algae, fungi, and bryozoa results in preferential dissolution along joints, stylolites, and bedding planes to form shallow spindle-shaped solution pits over the entire surface and sides of the karren. The solution pits average 1 cm length by 0.4 cm depth densely covering rock surfaces. This study suggests that seasonal bioerosion may constitute a more important geomorphic factor in lacustrine systems than previously recognized.

  7. Zeolite Formation and Weathering Processes Within the Martian Regolith: An Antarctic Analog

    NASA Technical Reports Server (NTRS)

    Gibson, E. K.; McKay, D. S.; Wentworth, S. J.; Socki, R. A.

    2003-01-01

    As more information is obtained about the nature of the surface compositions and processes operating on Mars, it is clear that significant erosional and depositional features are present on the surface. Apparent aqueous or other fluid activity on Mars has produced many of the erosional and outflow features observed. Evidence of aqueous activity on Mars has been reported by earlier studies. Gooding and colleagues championed the cause of pre-terrestrial aqueous alteration processes recorded in Martian meteorites. Oxygen isotope studies on Martian meteorites by Karlsson et al. and Romenek et al. gave evidence for two separate water reservoirs on Mars. The oxygen isotopic compositions of the host silicate minerals was different from the oxygen isotopic composition of the secondary alteration products within the SNC meteorites. This implied that the oxygen associated with fluids which produced the secondary alteration was from volatiles which were possibly added to the planetary inventory after formation of the primary silicates from which the SNC s were formed. The source of the oxygen may have been from a cometary or volatile-rich veneer added to the planet in its first 600 million years.

  8. National Weather Service

    MedlinePLUS

    ... Weather Fire Weather Sun/Moon Long Range Forecasts Climate Prediction PAST WEATHER Past Weather Heating/Cooling Days ... Radio NWS CAP Feeds PAST WEATHER Past Weather Climate Monitoring Heating/Cooling Days Monthly Temps Records Astronomical ...

  9. Weathering processes in the Rio Icacos and Rio Mameyes watersheds in Eastern Puerto Rico: Chapter I in Water quality and landscape processes of four watersheds in eastern Puerto Rico

    USGS Publications Warehouse

    Buss, Heather L.; White, Arthur F.

    2012-01-01

    Streams draining watersheds of the two dominant lithologies (quartz diorite and volcaniclastic rock) in the Luquillo Experimental Forest of eastern Puerto Rico have very high fluxes of bedrock weathering products. The Ro Blanco quartz diorite in the Icacos watershed and the Fajardo volcaniclastic rocks in the Mameyes watershed have some of the fastest documented rates of chemical weathering of siliceous rocks in the world. Rapid weathering produces thick, highly leached saprolites in both watersheds that lie just below the soil and largely isolate subsurface biogeochemical and hydrologic processes from those in the soil. The quartz diorite bedrock in the Icacos watershed weathers spheroidally, leaving large, relatively unweathered corestones that are enveloped by slightly weathered rock layers called rindlets. The rindlets wrap around the corestones like an onionskin. Within the corestones, biotite oxidation is thought to induce the spheroidal fracturing that leads to development of rindlets; plagioclase in the rindlets dissolves, creating additional pore spaces. Near the rindlet-saprolite interface, the remaining plagioclase dissolves, hornblende dissolves to completion, and precipitation of kaolinite, gibbsite, and goethite becomes pervasive. In the saprolite, biotite weathers to kaolinite and quartz begins to dissolve. In the soil layer, both quartz and kaolinite dissolve. The volcaniclastic bedrock of the Mameyes watershed weathers even faster than the quartz diorite bedrock of the Icacos watershed, leaving thicker saprolites that are devoid of all primary minerals except quartz. The quartz content of volcaniclastic bedrock may help to control watershed geomorphology; high-quartz rocks form thick saprolites that blanket ridges. Hydrologic flow paths within the weathering profiles vary with total fluid flux, and they influence the chemistry of streams. Under low-flow conditions, the Ro Icacos and its tributaries are fed by rainfall and by groundwater from the fracture zones; during storm events, intense rainfall rapidly raises stream levels and water is flushed through the soil as shallow flow. As a result, weathering constituents that shed into streamwaters are dominated by rindlet-zone weathering processes during base flow and by soil weathering processes during stormflow. The upper reaches of the Mameyes watershed are characterized by regolith more than 35 meters thick in places that contains highly fractured rock embedded in its matrix. Weathering contributions to stream chemistry at base flow are predicted to be more spatially variable in the Mameyes watershed than in the Icacos watershed owing to the more complex subsurface weathering profile of the volcaniclastic bedrocks of the Mameyes watershed.

  10. The State of Space Weather Scientific ModelingAn Introduction

    NASA Astrophysics Data System (ADS)

    Watermann, J.; Vainio, R.; Lilensten, J.; Belehaki, A.; Messerotti, M.

    2009-11-01

    The discipline of "Space Weather" is built on the scientific foundation of solar-terrestrial physics but with a strong orientation toward applied research. Models describing the solar-terrestrial environment are therefore at the heart of this discipline, for both physical understanding of the processes involved and establishing the capability to predict the consequences of these processes. This issue of Space Science Reviews contains four topical reviews on primarily European scientific progress in understanding and modeling space weather phenomena. The four reviews deal with (i) monitoring, modeling and predicting solar weather, (ii) the radiation environment of the Earth, (iii) solar wind disturbances and their interaction with geospace, and (iv) the upper atmosphere's response to space weather events.

  11. Space Weathering of Lunar Rocks

    NASA Technical Reports Server (NTRS)

    Noble, S. K.; Keller, L. P.; Christoffersen, R.; Rahman, Z.

    2012-01-01

    All materials exposed at the lunar surface undergo space weathering processes. On the Moon, boulders make up only a small percentage of the exposed surface, and areas where such rocks are exposed, like central peaks, are often among the least space weathered regions identified from remote sensing data. Yet space weathered surfaces (patina) are relatively common on returned rock samples, some of which directly sample the surface of larger boulders. Because, as witness plates to lunar space weathering, rocks and boulders experience longer exposure times compared to lunar soil grains, they allow us to develop a deeper perspective on the relative importance of various weathering processes as a function of time.

  12. The use of imprecise processing to improve accuracy in weather and climate prediction

    SciTech Connect

    Düben, Peter D.; McNamara, Hugh; Palmer, T.N.

    2014-08-15

    The use of stochastic processing hardware and low precision arithmetic in atmospheric models is investigated. Stochastic processors allow hardware-induced faults in calculations, sacrificing bit-reproducibility and precision in exchange for improvements in performance and potentially accuracy of forecasts, due to a reduction in power consumption that could allow higher resolution. A similar trade-off is achieved using low precision arithmetic, with improvements in computation and communication speed and savings in storage and memory requirements. As high-performance computing becomes more massively parallel and power intensive, these two approaches may be important stepping stones in the pursuit of global cloud-resolving atmospheric modelling. The impact of both hardware induced faults and low precision arithmetic is tested using the Lorenz '96 model and the dynamical core of a global atmosphere model. In the Lorenz '96 model there is a natural scale separation; the spectral discretisation used in the dynamical core also allows large and small scale dynamics to be treated separately within the code. Such scale separation allows the impact of lower-accuracy arithmetic to be restricted to components close to the truncation scales and hence close to the necessarily inexact parametrised representations of unresolved processes. By contrast, the larger scales are calculated using high precision deterministic arithmetic. Hardware faults from stochastic processors are emulated using a bit-flip model with different fault rates. Our simulations show that both approaches to inexact calculations do not substantially affect the large scale behaviour, provided they are restricted to act only on smaller scales. By contrast, results from the Lorenz '96 simulations are superior when small scales are calculated on an emulated stochastic processor than when those small scales are parametrised. This suggests that inexact calculations at the small scale could reduce computation and power costs without adversely affecting the quality of the simulations. This would allow higher resolution models to be run at the same computational cost.

  13. The use of imprecise processing to improve accuracy in weather & climate prediction

    NASA Astrophysics Data System (ADS)

    Dben, Peter D.; McNamara, Hugh; Palmer, T. N.

    2014-08-01

    The use of stochastic processing hardware and low precision arithmetic in atmospheric models is investigated. Stochastic processors allow hardware-induced faults in calculations, sacrificing bit-reproducibility and precision in exchange for improvements in performance and potentially accuracy of forecasts, due to a reduction in power consumption that could allow higher resolution. A similar trade-off is achieved using low precision arithmetic, with improvements in computation and communication speed and savings in storage and memory requirements. As high-performance computing becomes more massively parallel and power intensive, these two approaches may be important stepping stones in the pursuit of global cloud-resolving atmospheric modelling. The impact of both hardware induced faults and low precision arithmetic is tested using the Lorenz '96 model and the dynamical core of a global atmosphere model. In the Lorenz '96 model there is a natural scale separation; the spectral discretisation used in the dynamical core also allows large and small scale dynamics to be treated separately within the code. Such scale separation allows the impact of lower-accuracy arithmetic to be restricted to components close to the truncation scales and hence close to the necessarily inexact parametrised representations of unresolved processes. By contrast, the larger scales are calculated using high precision deterministic arithmetic. Hardware faults from stochastic processors are emulated using a bit-flip model with different fault rates. Our simulations show that both approaches to inexact calculations do not substantially affect the large scale behaviour, provided they are restricted to act only on smaller scales. By contrast, results from the Lorenz '96 simulations are superior when small scales are calculated on an emulated stochastic processor than when those small scales are parametrised. This suggests that inexact calculations at the small scale could reduce computation and power costs without adversely affecting the quality of the simulations. This would allow higher resolution models to be run at the same computational cost.

  14. Slope processes in weathered volcaniclastic rocks of the Camaldoli hill (Naples, Italy): Geomorphologic and Engineering-Geological aspects

    NASA Astrophysics Data System (ADS)

    Calcaterra, D.; Coppin, D.; Palma, B.; Parise, M.; Orsi, G.; de Vita, S.; di Vito, M. A.

    2003-04-01

    Following the geological study performed by Orsi et al. (this session), the main results of a geomorphologic and engineering-geological investigation of the stability conditions of the Camaldoli hill (urban area of Naples) are here presented. The Camaldoli hill, the highest peak of the Phlegraean Fields caldera (452 m asl), is characterized by relief energy of a few hundreds of meters, and by high slope gradients, which frequently reach the verticality. Low-order, structurally controlled channels drain the hillslopes; the development of stepped longitudinal profiles in the channels is related to the alternance of rocks and soils. The geological framework of the hill represent a further factor predisposing to mass movements and soil erosion. The Camaldoli hill is in fact characterized, as already highlighted by Orsi et al., by a basal sequence of jointed weak tuffs, overlain by some tens of metres of loose, unconsolidated pyroclastic terrains, ranging in age from about 12.000 and 4.000 yrs. BP. The latter deposits are generally weathered in their upper layers, as a consequence of interaction with decay agents and of past slope instabilities. Present-day morphodynamics of the hill is ruled by the occurrence of a variety of slope processes. Shallow landslides involve the weathered portion of the youngest pyroclastic products, showing features typical of slides or falls. Such events, which usually start in the upper reaches of the slope, may undergo different evolution, essentially controlled by the local slope morphology: (i) low-mobility soil slides-debris flows on open slopes; (ii) slides/falls evolving to hyperconcentrated flows along channels. The first processes have been seldom observed on open slopes, while the transition from slides/falls to hyperconcentrated flows along channels seems much more diffuse in the study area. The flows are generally fed, under intense to extreme rainfall events, by the re-mobilization of pre-existing landslide debris. The upper tuff formations (namely, the Neapolitan Yellow Tuff) are involved in falls and topple failures, which can detach volumes up to some tens of cubic metres, frequently reaching the lowest sectors of the slope, close to, if not within, the urbanized area. Eventually, accelerated soil erosion plays a major role in the open slopes, where evidences of sheet, rills and gullies have been surveyed. Joining the contribution of volcanologists and engineering-geologists, a tentative evaluation of the volumes susceptible to be mobilized by instability processes acting on the surficial, weathered cover of the loose pyroclastics was performed, adopting different methodologies. The so obtained results are compared and discussed in the paper: overall, they provide evidence of a widespread proneness to slope instability, which in turn may result into a serious threat to the diffuse settlements and infrastructures located at the Camaldolis foothill.

  15. Process evaluation results from the HEALTHY physical education intervention

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Process evaluation is an assessment of the implementation of an intervention. A process evaluation component was embedded in the HEALTHY study, a primary prevention trial for Type 2 diabetes implemented over 3 years in 21 middle schools across the United States. The HEALTHY physical education (PE) i...

  16. Process Evaluation Results from the HEALTHY Physical Education Intervention

    ERIC Educational Resources Information Center

    Hall, William J.; Zeveloff, Abigail; Steckler, Allan; Schneider, Margaret; Thompson, Deborah; Pham, Trang; Volpe, Stella L.; Hindes, Katie; Sleigh, Adriana; McMurray, Robert G.

    2012-01-01

    Process evaluation is an assessment of the implementation of an intervention. A process evaluation component was embedded in the HEALTHY study, a primary prevention trial for Type 2 diabetes implemented over 3 years in 21 middle schools across the United States. The HEALTHY physical education (PE) intervention aimed at maximizing student…

  17. Physical-chemical processes in a protoplanetary cloud

    NASA Technical Reports Server (NTRS)

    Lavrukhina, Avgusta K.

    1991-01-01

    Physical-chemical processes in a protoplanetary cloud are discussed. The following subject areas are covered: (1) characteristics of the chemical composition of molecular interstellar clouds; (2) properties and physico-chemical process in the genesis of interstellar dust grains; and (3) the isotope composition of volatiles in bodies of the Solar System.

  18. Brazilian Space Weather Program

    NASA Astrophysics Data System (ADS)

    Padilha, Antonio; Takahashi, Hisao; de Paula, Eurico; Sawant, Hanumant; de Campos Velho, Haroldo; Vitorello, Icaro; Costa, Joaquim; Souza, Jonas; Cecatto, José; Mendes, Odim; Gonzalez Alarcon, Walter Demétrio

    A space weather program is being initiated at the Brazilian National Institute for Space Research (INPE) to study events from their initiation on the sun to their impacts on the earth, including their effects on space-based and ground-based technological systems. The program is built on existing capabilities at INPE, which include scientists with a long tradition and excellence in the observation, analysis and modeling of solar and solar-terrestrial phenomena and an array of geophysical instruments that spans all over the Brazilian territory from the north to south of the magnetic dip equator. Available sensors include solar radio frequency receivers and telescopes, optical instruments and solar imagers, GNSS receivers, ionosondes, radars, allsky imagers, magnetometers and cosmic ray detectors. In the equatorial region, ionosphere and thermosphere constitute a coupled system with electrodynamical and plasma physical processes being responsible for a variety of peculiar phenomena. The most important of them are the equatorial electrojet current system and its instabilities, the equatorial ionization anomaly, and the plasma instabilities/irregularities of the night-time ionosphere (associated with the plasma bubble events). In addition, space weather events modify the equatorial ionosphere in a complex and up to now unpredictable manner. Consequently, a main focus of the program will be on monitoring the low, middle and upper atmosphere phenomena and developing a predictive model of the equatorial ionosphere through data assimilation, that could help to mitigate against the deleterious effects on radio communications and navigation systems. The technological, economic and social importance of such activities was recognized by the Brazilian government and a proposal for funding was approved for the period 2008-2011. New ground instruments will be installed during this period allowing us to extend our current capability to provide space weather observations, accurate forecasts of space weather conditions, and timely hazard alert warnings. The program is expected to be fully operational for the peak activity of the next solar maximum, but for its future growth and development it is essential to have a wide network of international collaborations.

  19. A model of weathering intensity for the Australian continent

    NASA Astrophysics Data System (ADS)

    Wilford, J.

    2013-12-01

    Regolith encompasses all weathered materials in the zone between the Earth's surface and fresh bedrock at depth. This weathered zone includes the soil, which may constitute the whole of the regolith profile or represent only its upper part. Important hydrological and biogeochemical processes operate within the regolith, including the infiltration and storage of near-surface water and nutrients, which sustain agricultural productivity. The degree to which the regolith is weathered (or its weathering intensity) is intrinsically linked to the factors involved in soil formation including parent material, climate, topography, biota and time. The degree to which the bedrock or sediments are weathered has a significant effect on the nature and distribution of regolith materials. There is commonly a strong correlation between weathering intensity and the degree of soil development as well as the depth of the weathering front. Changes in weathering intensity correspond to changes in the geochemical and physical properties of bedrock, ranging from essentially unweathered parent materials through to intensely weathered and leached regolith where all traits of the original protolith (original unweathered rock) are overprinted or lost altogether. With increasing weathering intensity we see mineral and geochemical convergence to more resistant secondary weathered materials including clay, silica, and various oxides. A weathering intensity index (WII) over the Australian continent has been developed at a 100 m resolution using two regression models based on airborne gamma-ray spectrometry imagery and the Shuttle Radar Topography Mission (SRTM) elevation data. Airborne gamma-ray spectrometry measures the concentration of three radioelements -- potassium (K), thorium (Th) and uranium (U) at the Earth's surface. The total gamma-ray flux (dose) is also calculated based on the weighted additions of the three radioelements. In general K is leached with increasing weathering whereas Th and U typically show increases due to their association in clays and oxides in the profile. These geochemical relationships underpin the first model prediction. In the case where no gamma-ray data is available or where the bedrock is very low in radioelements (e.g. basalt, quartz-rich sandstone) surface relief is used as surrogate in the second prediction model. The two models are combined to generate a weathering intensity index of the Australian continent. The weathering intensity index has been developed for erosional landscapes but also provides useful information on deposition processes and materials. The weathering intensity prediction is evaluated with surface geochemistry (compared with geochemical indices) and previous regolith-landform mapping. The use of the weathering intensity index in natural resource management and mineral exploration is discussed.

  20. Getting Middle-School Students up and Moving: What's the Role of School and Neighborhood Environments...and the Weather: Studying the Effect of Neighborhood and School Environments on Youth Physical Activity Levels. Program Results

    ERIC Educational Resources Information Center

    Nakashian, Mary

    2008-01-01

    Researchers at the Harvard Prevention Research Center at Harvard University School of Public Health examined how physical and social environments of schools and neighborhoods shape routine physical activities of students attending 10 middle schools in the Boston area. They also analyzed the effect of weather conditions on student physical…

  1. Analysis of weather patterns associated with air quality degradation and potential health impacts

    EPA Science Inventory

    Emissions from anthropogenic and natural sources into the atmosphere are determined in large measure by prevailing weather conditions through complex physical, dynamical and chemical processes. Air pollution episodes are characterized by degradation in air quality as reflected by...

  2. Physics-based signal processing algorithms for micromachined cantilever arrays

    DOEpatents

    Candy, James V; Clague, David S; Lee, Christopher L; Rudd, Robert E; Burnham, Alan K; Tringe, Joseph W

    2013-11-19

    A method of using physics-based signal processing algorithms for micromachined cantilever arrays. The methods utilize deflection of a micromachined cantilever that represents the chemical, biological, or physical element being detected. One embodiment of the method comprises the steps of modeling the deflection of the micromachined cantilever producing a deflection model, sensing the deflection of the micromachined cantilever and producing a signal representing the deflection, and comparing the signal representing the deflection with the deflection model.

  3. Physical and chemical characterization of bioaerosols - Implications for nucleation processes

    NASA Astrophysics Data System (ADS)

    Ariya, P. A.; Sun, J.; Eltouny, N. A.; Hudson, E. D.; Hayes, C. T.; Kos, G.

    The importance of organic compounds in the oxidative capacity of the atmosphere, and as cloud condensation and ice-forming nuclei, has been recognized for several decades. Organic compounds comprise a significant fraction of the suspended matter mass, leading to local (e.g. toxicity, health hazards) and global (e.g. climate change) impacts. The state of knowledge of the physical chemistry of organic aerosols has increased during the last few decades. However, due to their complex chemistry and the multifaceted processes in which they are involved, the importance of organic aerosols, particularly bioaerosols, in driving physical and chemical atmospheric processes is still very uncertain and poorly understood. Factors such as solubility, surface tension, chemical impurities, volatility, morphology, contact angle, deliquescence, wettability, and the oxidation process are pivotal in the understanding of the activation processes of cloud droplets, and their chemical structures, solubilities and even the molecular configuration of the microbial outer membrane, all impact ice and cloud nucleation processes in the atmosphere. The aim of this review paper is to assess the current state of knowledge regarding chemical and physical characterization of bioaerosols with a focus on those properties important in nucleation processes. We herein discuss the potential importance (or lack thereof) of physical and chemical properties of bioaerosols and illustrate how the knowledge of these properties can be employed to study nucleation processes using a modeling exercise. We also outline a list of major uncertainties due to a lack of understanding of the processes involved or lack of available data. We will also discuss key issues of atmospheric significance deserving future physical chemistry research in the fields of bioaerosol characterization and microphysics, as well as bioaerosol modeling. These fundamental questions are to be addressed prior to any definite conclusions on the potential significance of the role of bioaerosols on physico-chemical atmospheric processes and that of climate.

  4. Weatherizing America

    SciTech Connect

    Stewart, Zachary; Bergeron, T.J.; Barth, Dale; Qualis, Xavier; Sewall, Travis; Fransen, Richard; Gill, Tony

    2009-01-01

    As Recovery Act money arrives to expand home weatherization programs across the country, Zachary Stewart of Phoenix, Ariz., and others have found an exciting opportunity not only to start working again, but also to find a calling.

  5. Weatherizing America

    ScienceCinema

    Stewart, Zachary; Bergeron, T.J.; Barth, Dale; Qualis, Xavier; Sewall, Travis; Fransen, Richard; Gill, Tony;

    2013-05-29

    As Recovery Act money arrives to expand home weatherization programs across the country, Zachary Stewart of Phoenix, Ariz., and others have found an exciting opportunity not only to start working again, but also to find a calling.

  6. Limits to weathering and Earth Surface climate feedbacks

    NASA Astrophysics Data System (ADS)

    Dixon, J. L.; von Blanckenburg, F.

    2011-12-01

    Chemical weathering of silicate rocks consumes CO2 from the atmosphere, thus controlling global climate over geologic timescales through temperature-dependent feedbacks. Weathering is thought to accelerate by the increased exposure of minerals in rapidly eroding regions of high relief, suggesting that mountain building may be the primary driver of CO2 withdrawal. That chemical weathering rates and physical erosion rates are tightly correlated has supported this hypothesis, but this relationship is predominantly valid for soil-mantled landscapes. Here we analyze the sensitivity of climate-uplift-weathering feedbacks using a new global compilation of long term, soil-based denudation and weathering rates from cosmogenic nuclides and short term, river-based sediment and dissolved loads. Our data show that the rate of soil weathering obeys a rough global limit of 135 t km-2 y-1. Yet river dissolved loads from rapidly eroding mountain belts suggest that these landscapes also obey or fall below the limit of weathering observed for soils. We combine a global digital terrain model with correlations between relief, denudation and weathering to derive a global weathering budget. We observe that relative to today, increases in global denudation rates result in only minor increases in global weathering fluxes compared to the potential changes that could result from increasing mineral weathering intensity via changes in climate. Considering that rapidly uplifting mountain belts are a small component of the continental land surface, even if weathering fluxes in such areas were higher than today, they would likely represent a minor contribution to global CO2 withdrawal. Rather, we suggest that climate feedbacks operate best in landscapes of modest relief, soil-covered, and in a permanent process of rejuvenation.

  7. Comparison between physical variables acquired by a new multiparametric platform, ELFO, and data calculated by a three-dimensional hydrodynamic model in different weather conditions at Tiber River mouth (Latium coast, Italy)

    NASA Astrophysics Data System (ADS)

    Bonamano, Simone; Piermattei, Viviana; Marcelli, Marco; Peviani, Maximo

    2010-05-01

    The coastal ecosystem is characterized by high variability physical processes, which are strongly influenced by sudden changes in weather conditions. For this reason instruments able to collect data in a short time or mathematical models able to simulate the same phenomena from experimental data are basic. In this study in situ data are compared with data calculated by three-dimensional hydrodynamic model. The multiparametric platform was developed ad hoc by Laboratory of Experimental Oceanology and Marine Ecology (DECOS, Tuscia University) for coastal monitoring by small vessels (ELFO), and integrates temperature, conductivity, dissolved oxygen and suspended solids measures with bio-optical measures like fluorescence, photosynthetic efficiency and PAR. The hydrodynamic model is the three-dimensional coastal hydrodynamic DELFT3D-FLOW simulating processes of temperature and salinity diffusion and the transport of suspended sediment (cohesive and non cohesive) in the water column. This study analyses the area at mouth of Tiber river investigated by two surveys wiht different weather conditions. Data collected during the first survey were used to calibrate the DELFT3D-FLOW model which computational domain extends from the Argentario headland to Capo Anzio. A microscale wind field (resolution of about 7 km), provided by the atmospheric model COSMO-ME (developed by CNMCA of Aeronautica Militare, Italy), was used to reproduce the hydrodynamic field and the distribution of the physical variables of the whole period. In this way the data calculated by the model can be compared with those collected in situ during the second survey. Moreover dynamic phenomena existed between the two monitoring periods can be investigated.

  8. Rainy Weather Science.

    ERIC Educational Resources Information Center

    Reynolds, Karen

    1996-01-01

    Presents ideas on the use of rainy weather for activities in the earth, life, and physical sciences. Topics include formation and collision of raindrops, amount and distribution of rain, shedding of water by plants, mapping puddles and potholes, rainbow formation, stalking storms online, lightning, and comparing particles in the air before and…

  9. Rainy Weather Science.

    ERIC Educational Resources Information Center

    Reynolds, Karen

    1996-01-01

    Presents ideas on the use of rainy weather for activities in the earth, life, and physical sciences. Topics include formation and collision of raindrops, amount and distribution of rain, shedding of water by plants, mapping puddles and potholes, rainbow formation, stalking storms online, lightning, and comparing particles in the air before and

  10. Waste glass weathering

    SciTech Connect

    Bates, J.K.; Buck, E.C.

    1993-12-31

    The weathering of glass is reviewed by examining processes that affect the reaction of commercial, historical, natural, and nuclear waste glass under conditions of contact with humid air and slowly dripping water, which may lead to immersion in nearly static solution. Radionuclide release data from weathered glass under conditions that may exist in an unsaturated environment are presented and compared to release under standard leaching conditions. While the comparison between the release under weathering and leaching conditions is not exact, due to variability of reaction in humid air, evidence is presented of radionuclide release under a variety of conditions. These results suggest that both the amount and form of radionuclide release can be affected by the weathering of glass.

  11. Gendering Processes in the Field of Physical Education

    ERIC Educational Resources Information Center

    Berg, Paivi; Lahelma, Elina

    2010-01-01

    In Finnish secondary schools, girls and boys are taught physical education (PE) in separate groups. A male teacher normally teaches the boys and a female teacher teaches the girls. Focusing on PE teachers' comments in two different ethnographic studies of seventh graders (13-14-year-olds), we examine the processes that reproduce or challenge the…

  12. Gendering Processes in the Field of Physical Education

    ERIC Educational Resources Information Center

    Berg, Paivi; Lahelma, Elina

    2010-01-01

    In Finnish secondary schools, girls and boys are taught physical education (PE) in separate groups. A male teacher normally teaches the boys and a female teacher teaches the girls. Focusing on PE teachers' comments in two different ethnographic studies of seventh graders (13-14-year-olds), we examine the processes that reproduce or challenge the

  13. Heat Transfer Processes for the Thermal Energy Balance of Organisms. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    ERIC Educational Resources Information Center

    Stevenson, R. D.

    This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module describes heat transfer processes involved in the exchange of heat…

  14. Remote sensing of atmospheric particulates: Technological innovation and physical limitations in applications to short-range weather prediction

    NASA Technical Reports Server (NTRS)

    Curran, R. J.; Kropfil, R.; Hallett, J.

    1984-01-01

    Techniques for remote sensing of particles, from cloud droplet to hailstone size, using optical and microwave frequencies are reviewed. The inherent variability of atmospheric particulates is examined to delineate conditions when the signal can give information to be effectively utilized in a forecasting context. The physical limitations resulting from the phase, size, orientation and concentration variability of the particulates are assessed.

  15. Physics-based model for electro-chemical process

    SciTech Connect

    Zhang, Jinsuo

    2013-07-01

    Considering the kinetics of electrochemical reactions and mass transfer at the surface and near-surface of the electrode, a physics-based separation model for separating actinides from fission products in an electro-refiner is developed. The model, taking into account the physical, chemical and electrochemical processes at the electrode surface, can be applied to study electrorefining kinetics. One of the methods used for validation has been to apply the developed model to the computation of the cyclic voltammetry process of PuCl{sub 3} and UCl{sub 3} at a solid electrode in molten KCl-LiCl. The computed results appear to be similar to experimental measures. The separation model can be applied to predict materials flows under normal and abnormal operation conditions. Parametric studies can be conducted based on the model to identify the most important factors that affect the electrorefining processes.

  16. Snowslip Mountain Weather Station, MT

    USGS Multimedia Gallery

    USGS Physical Scientist Erich Peitzsch sets up a weather station on Snowslip Mountain in Glacier National Park. It provides meteorological data for avalanche forecasting and research, including wind speed and direction, air temperature, relative humidity, and net radiation measurements....

  17. Fluid Dynamics Applied to Streams. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    ERIC Educational Resources Information Center

    Cowan, Christina E.

    This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module deals specifically with concepts that are basic to fluid flow and

  18. Pressure and Buoyancy in Aquatic Ecosystems. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    ERIC Educational Resources Information Center

    Cowan, Christina E.

    This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module explores some of the characteristics of aquatic organisms which can be

  19. Light and Sound: Evolutionary Aspects. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    ERIC Educational Resources Information Center

    Roseman, Leonard D.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module is concerned with the exchange of energy between an organism and its environment in

  20. Soil Heat Flow. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    ERIC Educational Resources Information Center

    Simpson, James R.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. Soil heat flow and the resulting soil temperature distributions have ecological consequences…

  1. Biological Production in Lakes. Physical Processes in Terrestrial and Aquatic Ecosystems, Ecological Processes.

    ERIC Educational Resources Information Center

    Walters, R. A.; Carey, G. F.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. Primary production in aquatic ecosystems is carried out by phytoplankton, microscopic plants…

  2. Transpiration and Leaf Temperature. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    ERIC Educational Resources Information Center

    Gates, David M.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This report introduces two models of the thermal energy budget of a leaf. Typical values for…

  3. Rb Sr and K Ar systems of biotite in surface environments regulated by weathering processes with implications for isotopic dating and hydrological cycles of Sr isotopes

    NASA Astrophysics Data System (ADS)

    Jeong, Gi Young; Cheong, Chang-Sik; Kim, Jeongmin

    2006-09-01

    Biotite is widely used for Rb-Sr and K-Ar isotopic dating and influences Sr isotope geochemistry of hydrological regimes. The isotopic system of biotite behaves diversely in response to surface weathering; i.e. the complete preservation of original Rb-Sr and K-Ar isotopic ages or dramatic reduction. In this study, we have explored the relation between the behavior of isotopic systems and complex weathering processes of biotites in the weathering profiles distributed on the Mesozoic granitoids in South Korea. In the lower parts of the profiles, biotite in the early stages of weathering was transformed into either oxidized biotite or hydrobiotite, with a mass release of 87Sr and 40Ar forced by the rapid oxidation of ferrous iron. During the transformation to oxidized biotite, 87Sr and 40Ar were preferentially released relative to Rb and K, respectively, via solid-state diffusion through the biotite lattice, resulting in a drastic reduction of original isotopic age. The reduction of Rb-Sr age was greater than that of K-Ar age because K was preferentially released over Rb whereas 87Sr and 40Ar were released proportionally to each other. However, during the transformation of biotite to hydrobiotite (i.e., to regularly interstratified biotite-vermiculite), 87Sr, Rb, 40Ar, and K were completely retained in the alternating biotite interlayer, and thus the original isotopic age can be preserved. In the upper parts of the profiles, where iron oxidation was almost completed, 87Sr, Rb, 40Ar, and K were gradually and proportionally released, with no further significant change in isotopic age during the gradual transformation of the early-formed oxidized biotite into hydrobiotite and vermiculite or during their final decomposition to kaolinite. The ratios and amounts of isotopes released from weathered biotites are dependent upon the degree of iron oxidation and the pathways of mineralogical transformation. Regional and local variations in isotopic systems affected by particular weathering processes should be considered when dating biotite or biotite-bearing rocks in weathering environments, modeling the transfer of Sr isotopes to hydrologic regimes, and tracking the provenance of sediments.

  4. Integrated Research and Education in Solar Physics, Space Weather, and Energetic Charged Particles at the University of Arizona

    NASA Astrophysics Data System (ADS)

    Giacalone, J.

    2011-12-01

    I will discuss how a NSF Early-Career Award led to a new emphasis in solar physics at the University of Arizona (UA) that has enabled new opportunities for scientific research in this area, but has also led to new education and public-outreach initiatives. I will discuss the approach used to integrate education with research, emphasizing the importance of the prestige of the CAREER award itself. A particular highlight from this project was a summer school in solar physics that was held for four consecutive years from 2006-2009 aimed at beginning graduate students, but also had a number of advanced undergraduates as well. The award was also used to support workshops for local-area middle-school teachers on topics germane to solar physics that could be instituted in their respective school's curricula. The award also subsidized a number of graduate students and postdoctoral researchers at the UA promoting their career development. While the focus of this presentation will be on the educational and public-outreach aspects of this project, it is important emphasize that this project had a strong research component. The UA is a major research university and the award was instrumental in the development of the principal investigator's career, both in terms of obtaining tenure and promotion to full professor, and also to put him in a good position to secure extramural funding. Therefore, I will also discuss some key research highlights from this project as well.

  5. Stable Chromium Isotopes as tracer of changes in weathering processes and redox state of the ocean during Neoproterozoic glaciation

    NASA Astrophysics Data System (ADS)

    Dossing, L. N.; Gaucher, C.; Boggiani, P. C.; Frei, R.

    2010-12-01

    The chemistry of surface environments on Earth has essentially evolved from early anoxic conditions to a present day oxic state. How in detail this transition occurred is still a matter of debate but the last 200 million years (My) of the Neoproterozoic Era [(1000 to 542 million years ago (Ma)] show an emerging picture of large scale fluctuations in the redox state of the oceans [1-2]. The reasons for these fluctuations are to be sought in Earths atmospheric oxygenation which led to the rapid radiation of oxygen-utilizing macroscopic metazoans, but details regarding the nature of these fluctuations remain unclear. The Late Neoproterozoic is known for a number of widespread glaciations causing the return of ferruginous oceans which were absent for more than a billion years of Earth history. This study elaborates on the idea that Chromium (Cr) stable isotopes in Fe-rich chemical sediments deposited during glacial events are suitable for tracing oxygenation of surface environments through Earth's history [3]. The focus of this study is to apply the Cr isotope system to one of the Marinoan (650-630 Ma) glacio-marine sequences (Jacadigo Group, Brazil) in order to get a detailed spatial and relative temporal resolution of changes in weathering processes and redox states of the respective ocean basin during the depositional period of the sediments. The Jacadigo Group is a glacio-marine succession which is composed of the Urucum Fm. (sandstones) at the base, the Santa Cruz Fm. (BIFs) and the Puga Fm. (Fe-rich glacial diamictites) at the top. Cr stable isotope measurements on various BIF horizons of the Santa Cruz Fm. yielded positive ?53/52Cr values range from +0.4 to+ 0.9, while the overlying Fe-rich glaciogenic diamictites of the Puga Fm. show ?53/52Cr values range from to +0.1 to+ 0.4. These positively fractionated values correspond to positive ?53/52Cr values measured in other Late Neoproterozoic BIFs and speak for the occurrence of potential oxygenation pulses of the atmosphere during respective glacier retreat (deglaciation) stages, which enabled the oxidation and mobilization of trivalent Cr on land into the oceans. The nature of upward decreasing ?53/52Cr values from the Santa Cruz into the Puga Fm. has to be investigated further, but a decrease of such values would point to decreasing weathering intensities on land most probably as a consequence of oxygen drawdown from the atmosphere by oxygen-consuming metazoans for which a favourable habitat was created during the glacier retreat stages. [1] D.E. Canfield, S.W. Poulton, A.H. Knoll, G.M. Narbonne, G. Ross, T. Goldberg, H. Strauss, Ferruginous conditions dominated later Neoproterozoic deep-water chemistry, Science 321(2008) 949-952. [2] C. Scott, T.W. Lyons, A. Bekker, Y. Shen, S.W. Poulton, X. Chu, A.D. Anbar, Tracing the stepwise oxygenation of the Proterozoic ocean, Nature 452(2008) 456-U455. [3] R. Frei, C. Gaucher, S.W. Poulton, D.E. Canfield, Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes, Nature 461(2009) 250-253.

  6. Being qua becoming: Aristotle's "Metaphysics", quantum physics, and Process Philosophy

    NASA Astrophysics Data System (ADS)

    Johnson, David Kelley

    In Aristotle's First Philosophy, science and philosophy were partners, but with the rise of empiricism, went their separate ways. Metaphysics combined the rational and irrational (i.e. final cause/unmoved mover) elements of existence to equate being with substance, postulating prime matter as pure potential that was actuated by form to create everything. Modern science reveres pure reason and postulates its theory of being by a rigorous scientific methodology. The Standard Model defines matter as energy formed into fundamental particles via forces contained in fields. Science has proved Aristotle's universe wrong in many ways, but as physics delves deeper into the quantum world, empiricism is reaching its limits concerning fundamental questions of existence. To achieve its avowed mission of explaining existence completely, physics must reunite with philosophy in a metascience modeled on the First Philosophy of Aristotle. One theory of being that integrates quantum physics and metaphysics is Process Philosophy.

  7. How Physicists Made Stable Lvy Processes Physically Plausible

    NASA Astrophysics Data System (ADS)

    Schinckus, Christophe

    2013-08-01

    Stable Lvy processes have very interesting properties for describing the complex behaviour of non-equilibrium dissipative systems such as turbulence, anomalous diffusion or financial markets. However, although these processes better fit the empirical data, some of their statistical properties can raise several theoretical problems in empirical applications because they generate infinite variables. Econophysicists have developed statistical solutions to make these processes physically plausible. This paper presents a review of these analytical solutions (truncations) for stable Lvy processes and how econophysicists transformed them into data-driven processes. The evolution of these analytical solutions is presented as a progressive research programme provided by (econo)physicists for theoretical problems encountered in financial economics in the 1960s and the 1970s.

  8. Fourth National Aeronautics and Space Administration Weather and Climate Program Science Review

    NASA Technical Reports Server (NTRS)

    Kreins, E. R. (Editor)

    1979-01-01

    The NASA Weather and Climate Program has two major thrusts. The first involves the development of experimental and prototype operational satellite systems, sensors, and space facilities for monitoring and understanding the atmosphere. The second thrust involves basic scientific investigation aimed at studying the physical and chemical processes which control weather and climate. This fourth science review concentrated on the scientific research rather than the hardware development aspect of the program. These proceedings contain 65 papers covering the three general areas: severe storms and local weather research, global weather, and climate.

  9. Assessing processes in uncertain, complex physical phenomena and manufacturing

    SciTech Connect

    Booker, J. M.; Kerscher, W. J. III; Smith, R. E.

    2002-01-01

    PREDICT (Performance and Reliability Evaluation with Diverse Information Combination and Tracking) is a set of structured quantitative approaches for the evaluation of system performance based on multiple information sources. The methodology integrates diverse types and sources of information, and their associated uncertainties, to develop full distributions for performance metrics, such as reliability. The successful application of PREDICT has involved system performance assessment in automotive product development, aging nuclear weapons, and fatigued turbine jet engines. In each of these applications, complex physical, mechanical and materials processes affect performance, safety and reliability assessments. Processes also include the physical actions taken during manufacturing, quality control, inspections, assembly, etc. and the steps involved in product design, development and certification. In this paper, we will examine the various types of processes involved in the decision making leading to production in an automotive system reliability example. Analysis of these processes includes not only understanding their impact on performance and reliability, but also the uncertainties associated with them. The automotive example demonstrates some of the tools used in tackling the complex problem of understanding processes. While some tools and methods exist for understanding processes (man made and natural) and the uncertainties associated with them, many of the complex issues discussed are open for continued research efforts.

  10. Reconstructing chemical weathering, physical erosion and monsoon intensity since 25 Ma in the northern South China Sea: A review of competing proxies

    NASA Astrophysics Data System (ADS)

    Clift, Peter D.; Wan, Shiming; Blusztajn, Jerzy

    2014-03-01

    Reconstructing the changing strength of the East Asian summer monsoon has been controversial because different proxies, many being indirect measures of rainfall, tell contrasting stories about how this has varied over long periods of geologic time. Here we present new Sr isotope, grain-size and clastic flux data and synthesize existing proxies to reconstruct changing chemical erosion in the northern South China Sea since the Oligocene, using the links between weathering rates and monsoon strength established in younger sediments as a way to infer intensity. Chemical proxies such as K/Rb, K/Al and the Chemical Index of Alteration (CIA), together with clay proxies like kaolinite/(illite + chlorite) show a steady decline in alteration after a sharp fall following a maximum at the Mid Miocene Climatic Optimum (MMCO; 15.5-17.2 Ma), probably as a result of cooling global temperatures. In contrast, physical erosion proxies, including bulk Ti/Ca and clastic mass accumulation rates (MAR), show peaks at 21-23 Ma, ~ 19 Ma and 15.5-17.2 Ma, implying faster run-off in the absence of drainage capture. Rates increase again, likely driven by slightly increased run-off after 13 Ma, but decrease after 8 Ma, which is identified as a period of summer monsoon weakening. Sr isotope composition correlates with hematite/goethite and the spectral proxy CRAT to show stronger weathering linked to more monsoonal seasonality. These proxies argue for a strengthening of the East Asian Monsoon after 22-23 Ma, followed by an extended period of monsoon maximum between 18 and 10 Ma, then weakening. There is some suggestion that the summer monsoon may have strengthened since 3-4 Ma after reaching a minimum in the Pliocene.

  11. Significant impacts of radiation physics in the Weather Research and Forecasting model on the precipitation and dynamics of the West African Monsoon

    NASA Astrophysics Data System (ADS)

    Li, R.; Jin, J.; Wang, S.-Y.; Gillies, R. R.

    2015-03-01

    Precipitation from the West African Monsoon (WAM) provides food security and supports the economy in the region. As a consequence of the intrinsic complexities of the WAM's evolution, accurate simulations of the WAM and its precipitation regime, through the application of regional climate models, are challenging. We used the coupled Weather Research and Forecasting (WRF) and Community Land Model (CLM) to explore impacts of radiation physics on the precipitation and dynamics of the WAM. Our results indicate that the radiation physics schemes not only produce biases in radiation fluxes impacting radiative forcing, but more importantly, result in large bias in precipitation of the WAM. Furthermore, the different radiation schemes led to variations in the meridional gradient of surface temperature between the north that is the Sahara desert and the south Guinean coastline. Climate diagnostics indicated that the changes in the meridional gradient of surface temperature affect the position and strength of the African Easterly Jet as well as the low-level monsoonal inflow from the Gulf of Guinea. The net result was that each radiation scheme produced differences in the WAM precipitation regime both spatially and in intensity. Such considerable variances in the WAM precipitation regime and dynamics, resulting from radiation representations, likely have strong feedbacks within the climate system and so have inferences when it comes to aspects of predicted climate change both for the region and globally.

  12. A combined physical/microbial process for coal beneficiation

    SciTech Connect

    Noah, K.S.; Glenn, A.W.; Stevens, C.J.; McAtee, N.B.; McIlwain, M.E.; Andrews, G.F.

    1993-11-01

    A combined physical/microbial process for the removal of pyritic sulfur from coal was demonstrated in a 200 L aerated trough slurry reactor. The reactor was divided into six sections, each of which acted as both a physical separator and a bioreactor. Settled solids from sections 2 through 6 were recycled to section 1 which acted as a rougher. The objective was physical removal of the larger pyritic inclusions, which would take many days to biodegrade, and biodegradation of the micropyrite, which is difficult to remove physically. The process was operated continuously for 8 months, treating two Illinois No. 6 coals (4 months each). Reduction of 90% in-pyritic sulfur with 90% energy recovery and 35% ash removal was obtained for a low pyrite Monterey coal at a 5 day coal retention time and 20% (w/w) slurry concentration. Increased coal loading reduced performance apparently due to losses of sulfur oxidizing bacteria. A low pyrite Consol coal gave 63--77% pyrite reduction with 23--30% ash removal and 77--90% heating value recovery. Product coal pyritic sulfur analysis indicated no differences between treatments of Consol coal. This suggests that the coal residence time could be further reduced and the slurry concentration increased in future work.

  13. Weathering processes and the composition of inorganic material transported through the orinoco river system, Venezuela and Colombia

    USGS Publications Warehouse

    Stallard, R.F.; Koehnken, L.; Johnsson, M.J.

    1991-01-01

    The composition of river-borne material in the Orinoco River system is related primarily to erosion regime, which in turn is related to tectonic setting; especially notable is the contrast between material derived from tectonically active mountain belts and that from stable cratonic regions. For a particular morpho-tectonic region, the compositional suites of suspended sediment, bed material, overback deposits, and dissolved phases are fairly uniform are are typically distinct from whose of other regions. For each region, a consistent set of chemical weathering reactions can be formulated to explain the composition of dissolved and solid loads. In developing these formulations, erosion on slopes and storage of solids in soils and alluvial sediments are important considerations. Compositionally verymature sediment is derived from areas of thick soils where erosion is transport limited and from areas where sediments are stored for extended periods of time in alluvial deposits. Compositionally immature sediments are derived from tectonically active mountain belts where erosion is weathering limited. Weathering-limited erosion also is important in the elevated parts of the Guayana Shield within areas of sleep topography. Compared to the mountain belts, sediments derived from elevated parts of the Shield are more mature. A greater degree of chemical weathering seems to be needed to erode the rock types typical of the Shield. The major-element chemistry and mineral composition of sediment delivered by the Orinoco River to the ocean are controlled by rivers that have their headwaters in mountain belts and cross the Llanos, a region of alluvial plains within the foreland basin. The composition of sediments in rivers that drain the Shield seems to be established primarily at the site of soil formation, whereas for rivers that drain the mountain belts, additional weathering occurs during s episodes of storage on alluvial plains as sediments are transported across the Llanos to the main stem of the Orinoco. After mixing into the main stem, there seems to be little subsequent alteration of sediment. ?? 1991.

  14. CLARA: A Contemporary Approach to Physics Data Processing

    NASA Astrophysics Data System (ADS)

    Gyurjyan, V.; Abbott, D.; Carbonneau, J.; Gilfoyle, G.; Heddle, D.; Heyes, G.; Paul, S.; Timmer, C.; Weygand, D.; Wolin, E.

    2011-12-01

    CLARA (CLAS12 Reconstruction and Analysis framework) is CLAS12 physics data processing (PDP) application development framework based on a service oriented architecture (SOA). This framework allows users to design and deploy data processing services as well as dynamically compose PDP applications using available services. Services can be written in Java, C++, and Python languages. The PDP service bus provides a layer on top of a distributed pub-sub middleware implementation. This allows complex service composition and integration without writing a code. We believe that by deviating from the traditional self contained, monolithic PDP application models we can improve maintenance, scalability and quality of physics data analysis. The SOA approach also helps us to separate a specific service programmer from a PDP application designer. Examples of service creation and deployment, along with the CLAS12 track reconstruction application design are presented.

  15. Acute physical exercise affected processing efficiency in an auditory attention task more than processing effectiveness.

    PubMed

    Dutke, Stephan; Jaitner, Thomas; Berse, Timo; Barenberg, Jonathan

    2014-02-01

    Research on effects of acute physical exercise on performance in a concurrent cognitive task has generated equivocal evidence. Processing efficiency theory predicts that concurrent physical exercise can increase resource requirements for sustaining cognitive performance even when the level of performance is unaffected. This hypothesis was tested in a dual-task experiment. Sixty young adults worked on a primary auditory attention task and a secondary interval production task while cycling on a bicycle ergometer. Physical load (cycling) and cognitive load of the primary task were manipulated. Neither physical nor cognitive load affected primary task performance, but both factors interacted on secondary task performance. Sustaining primary task performance under increased physical and/or cognitive load increased resource consumption as indicated by decreased secondary task performance. Results demonstrated that physical exercise effects on cognition might be underestimated when only single task performance is the focus. PMID:24501145

  16. The physical basis of explosion and blast injury processes.

    PubMed

    Proud, W G

    2013-03-01

    Energetic materials are widely used in civilian and military applications, such as quarrying and mining, flares, and in munitions. Recent conflicts have involved the widespread use of improvised explosive devices to attack military, civilians and infrastructure. This article gives a basic overview of explosive technology and the underlying physical processes that produce the injuries encountered. In particular aspects relevant to primary and secondary injuries are discussed. PMID:23631318

  17. Influence of different natural physical fields on biological processes

    NASA Astrophysics Data System (ADS)

    Mashinsky, A. L.

    2001-01-01

    In space flight conditions gravity, magnetic, and electrical fields as well as ionizing radiation change both in size, and in direction. This causes disruptions in the conduct of some physical processes, chemical reactions, and metabolism in living organisms. In these conditions organisms of different phylogenetic level change their metabolic reactions undergo changes such as disturbances in ionic exchange both in lower and in higher plants, changes in cell morphology for example, gyrosity in Proteus ( Proteus vulgaris), spatial disorientation in coleoptiles of Wheat ( Triticum aestivum) and Pea ( Pisum sativum) seedlings, mutational changes in Crepis ( Crepis capillaris) and Arabidopsis ( Arabidopsis thaliana) seedling. It has been found that even in the absence of gravity, gravireceptors determining spatial orientation in higher plants under terrestrial conditions are formed in the course of ontogenesis. Under weightlessness this system does not function and spatial orientation is determined by the light flux gradient or by the action of some other factors. Peculiarities of the formation of the gravireceptor apparatus in higher plants, amphibians, fish, and birds under space flight conditions have been observed. It has been found that the system in which responses were accompanied by phase transition have proven to be gravity-sensitive under microgravity conditions. Such reactions include also the process of photosynthesis which is the main energy production process in plants. In view of the established effects of microgravity and different natural physical fields on biological processes, it has been shown that these processes change due to the absence of initially rigid determination. The established biological effect of physical fields influence on biological processes in organisms is the starting point for elucidating the role of gravity and evolutionary development of various organisms on Earth.

  18. Urgency of evolution-process congruent thinking in physics

    NASA Astrophysics Data System (ADS)

    Roychoudhuri, Chandrasekhar

    2015-09-01

    It is now generally recognized that physics has not been contributing anything conceptually fundamentally new beyond the century old Relativity and 90 years old Quantum Mechanics [1-4]. We have also started recognizing that there is an increasing rate of species extinction all over the world, especially since the last century [5]; and we are beginning to understand that the related problems are being steadily accelerated by human behavior to conquer nature, rather than understanding nature as is and living within its system logics [6,7]. We are beginning to appreciate that our long-term sustainability as a species literally depends upon proactively learning to nurture the entire bio-diversity [8-10]. Thus, humans must consciously become evolution process congruent thinkers. The evolutionary biologists have been crying out loud for us to listen [5,6, 8-10]. Social scientists, political scientists, economic scientists [13] have started chiming in to become consilient thinkers [6] for re-constructing sustainable societies. But, the path to consilient thinking requires us to recognize and accept a common vision based thinking process, which functionally serves as a uniting platform. I am articulating that platform as the "evolution process congruent thinking" (EPCT). Do physicists have any obligation to co-opt this EPCT? Is there any immediate and/or long-term gain for them? This paper argues affirmatively that co-opting EPCT is the best way to re-anchor physics back to reality ontology and develop newer and deeper understanding of natural phenomena based on understanding of the diverse interaction processes going on in nature. Physics is mature enough to acknowledge that all of our theories are "work in progress". This is a good time to start iteratively re-evaluating and re-structuring all the foundational postulates behind all the working theories. This will also consistently energize all the follow-on generation of physicists to keep on fully utilizing their evolution-given enquiring minds without being afraid by the prevailing culture of "publish-or-perish", requiring them to stay within the bounds of the prevailing theories as the final ones. Current physics thinking has been successfully driven by Measurable Data Modeling Epistemology (MDM-E); which is basically curve-fitting without demanding to understand the actual physical processes nature is carrying out. I am proposing to add an iterative repertoire, Interaction Process mapping Epistemology (IPM-E) over and above successful MDM-E. This will facilitate the physicists to become conceptual reverse engineers of nature. The gap between physicists and engineers will start melting down and our collective sustainability will be re-assured as successful engineers of nature.

  19. Process depending morphology and resulting physical properties of TPU

    NASA Astrophysics Data System (ADS)

    Frick, Achim; Spadaro, Marcel

    2015-12-01

    Thermoplastic polyurethane (TPU) is a rubber like material with outstanding properties, e.g. for seal applications. TPU basically provides high strength, low frictional behavior and excellent wear resistance. Though, due to segmented structure of TPU, which is composed of hard segments (HSs) and soft segments (SSs), physical properties depend strongly on the morphological arrangement of the phase separated HSs at a certain ratio of HSs to SSs. It is obvious that the TPU deforms differently depending on its bulk morphology. Basically, the morphology can either consist of HSs segregated into small domains, which are well dispersed in the SS matrix or of few strongly phase separated large size HS domains embedded in the SS matrix. The morphology development is hardly ruled by the melt processing conditions of the TPU. Depending on the morphology, TPU provides quite different physical properties with respect to strength, deformation behavior, thermal stability, creep resistance and tribological performance. The paper deals with the influence of important melt processing parameters, such as temperature, pressure and shear conditions, on the resulting physical properties tested by tensile and relaxation experiments. Furthermore the morphology is studied employing differential scanning calorimeter (DSC), transmission light microscopy (TLM), scanning electron beam microscopy (SEM) and transmission electron beam microscopy (TEM) investigations. Correlations between processing conditions and resulting TPU material properties are elaborated. Flow and shear simulations contribute to the understanding of thermal and flow induced morphology development.

  20. Quantum Processes and Dynamic Networks in Physical and Biological Systems.

    NASA Astrophysics Data System (ADS)

    Dudziak, Martin Joseph

    Quantum theory since its earliest formulations in the Copenhagen Interpretation has been difficult to integrate with general relativity and with classical Newtonian physics. There has been traditionally a regard for quantum phenomena as being a limiting case for a natural order that is fundamentally classical except for microscopic extrema where quantum mechanics must be applied, more as a mathematical reconciliation rather than as a description and explanation. Macroscopic sciences including the study of biological neural networks, cellular energy transports and the broad field of non-linear and chaotic systems point to a quantum dimension extending across all scales of measurement and encompassing all of Nature as a fundamentally quantum universe. Theory and observation lead to a number of hypotheses all of which point to dynamic, evolving networks of fundamental or elementary processes as the underlying logico-physical structure (manifestation) in Nature and a strongly quantized dimension to macroscalar processes such as are found in biological, ecological and social systems. The fundamental thesis advanced and presented herein is that quantum phenomena may be the direct consequence of a universe built not from objects and substance but from interacting, interdependent processes collectively operating as sets and networks, giving rise to systems that on microcosmic or macroscopic scales function wholistically and organically, exhibiting non-locality and other non -classical phenomena. The argument is made that such effects as non-locality are not aberrations or departures from the norm but ordinary consequences of the process-network dynamics of Nature. Quantum processes are taken to be the fundamental action-events within Nature; rather than being the exception quantum theory is the rule. The argument is also presented that the study of quantum physics could benefit from the study of selective higher-scale complex systems, such as neural processes in the brain, by virtue of mathematical and computational models that may be transferred from the macroscopic domain to the microscopic. A consequence of this multi-faceted thesis is that there may be mature analytical tools and techniques that have heretofore not been adequately recognized for their value to quantum physics. These may include adaptations of neural networks, cellular automata, chaotic attractors, and parallel processing systems. Conceptual and practical architectures are presented for the development of software and hardware environments to employ massively parallel computing for the modeling of large populations of dynamic processes.

  1. Weather control

    SciTech Connect

    Leepson, M.

    1980-09-05

    Weather modification, the intentional altering of atmospheric conditions to suit the purposes of humankind, has five basic forms: (1) fog dissipation; (2) rain and snow enhancement; (3) hail suppression; (4) lightning suppression; and (5) the abatement of severe storms such as hurricanes and tornadoes. The dissipation of fog and the seeding of clouds with dry ice or silver iodide to produce rain are the most successful weather modification techniques. Both are used extensively and with varying degrees of success in the United States and around the world. Cloud seeding, though, is not effective in easing the harshness of a drought, such as the one that hit the Southwest, Midwest and Great Plains this summer.

  2. Process evaluation results from the HEALTHY physical education intervention.

    PubMed

    Hall, William J; Zeveloff, Abigail; Steckler, Allan; Schneider, Margaret; Thompson, Deborah; Pham, Trang; Volpe, Stella L; Hindes, Katie; Sleigh, Adriana; McMurray, Robert G

    2012-04-01

    Process evaluation is an assessment of the implementation of an intervention. A process evaluation component was embedded in the HEALTHY study, a primary prevention trial for Type 2 diabetes implemented over 3 years in 21 middle schools across the United States. The HEALTHY physical education (PE) intervention aimed at maximizing student engagement in moderate-to-vigorous physical activity through delivery of structured lesson plans by PE teachers. Process evaluation data collected via class observations and interventionist interviews assessed fidelity, dose delivered, implementor participation, dose received and barriers. Process evaluation results indicate a high level of fidelity in implementing HEALTHY PE activities and offering 225 min of PE every 10 school days. Concerning dose delivered, students were active for approximately 33 min of class, representing an average of 61% of the class time. Results also indicate that PE teachers were generally engaged in implementing the HEALTHY PE curriculum. Data on dose received showed that students were highly engaged with the PE intervention; however, student misbehavior was the most common barrier observed during classes. Other barriers included teacher disengagement, large classes, limited gym space and poor classroom management. Findings suggest that the PE intervention was generally implemented and received as intended despite several barriers. PMID:22156231

  3. Time-scales of sedimentary transfer and weathering processes from U-series nuclides: Clues from the Himalayan rivers

    NASA Astrophysics Data System (ADS)

    Granet, M.; Chabaux, F.; Stille, P.; France-Lanord, C.; Pelt, E.

    2007-09-01

    In order to define time-scales of erosion and sedimentary transfer in the Himalaya, 238U- 234U- 230Th disequilibria have been analysed in river bank sediments and in bedloads collected along the Kali Gandaki river, one of the main Nepalese rivers, and in the Ghaghara and Gandak rivers, two major plain tributaries of the Ganges. The Th activity ratios and U/Th ratios in river sediments of the two Ganges tributaries constantly decrease from upstream to downstream. This is related to the maturation of sediments by weathering during their transfer to the plain. The U-series data allow to calculate a transfer time for the sediments in the alluvial Gangetic plain from the chain front to the confluence with the Ganges of about 100 kyr for both rivers. The Kali Gandaki river sediment data highlight a decrease of both the Th isotopic and U/Th ratios which is explained by a mixing between two sources with similar U/Th ratios but having suffered a different U-Th fractionation history. Interpretation of the U-series data in the frame of this scenario gives long time-scales of weathering of several 100's kyr for the Himalayan terranes. The results imply that Himalayan bedrocks are submitted to a long in situ stage of weathering before their erosion and transfer into the rivers. In addition, occurrence of similar U-Sr signatures in dissolved (i.e. < 0.1-0.2 ?m) and sediment phases of the Kali Gandaki river suggests that "dissolved" uranium could be carried by colloids constituted by sedimentary microparticles. This precludes the use of U-series disequilibria in this river to calculate weathering budgets and to assess whether the erosion is working at steady-state or not.

  4. Upconversion luminescent nanoparticles in physical sensing and in monitoring physical processes in biological samples

    NASA Astrophysics Data System (ADS)

    González-Béjar, María; Pérez-Prieto, Julia

    2015-12-01

    The most frequently used strategy for sensing is based on the emission variation of a photoactive system and it can be classified as chemical or physical depending on its response to either a chemical or a physical stimulus. There are a large number of luminescent nanomaterials that respond to chemical species, but comparatively, with the exception of temperature sensing, to date there are few examples showing the capacity of photoactive nanosystems responsive to physical stimuli, such as magnetic and electric fields, high radiation energy, tension/pressure, viscosity, etc, and very few of them comprise upconversion nanoparticles (UCNPs). These nanomaterials consist of an inorganic matrix doped with rare earth (RE) ions and can be advantageously used in sensing due to their unique optical features: near-infrared excitation, anti-Stokes emission, multiplexed emissions that span over a broad range (i.e. from the UV to NIR region depending on the nature of the RE ions), narrow emission bands, long emission lifetimes, high photostability, and non-photoblinking, among others. In this review we focus on the advances in the application of the luminescence of UCNPs for sensing environmental physical changes and for tracking physical processes in living systems.

  5. Weather Forecasting Systems and Methods

    NASA Technical Reports Server (NTRS)

    Mecikalski, John (Inventor); MacKenzie, Wayne M., Jr. (Inventor); Walker, John Robert (Inventor)

    2014-01-01

    A weather forecasting system has weather forecasting logic that receives raw image data from a satellite. The raw image data has values indicative of light and radiance data from the Earth as measured by the satellite, and the weather forecasting logic processes such data to identify cumulus clouds within the satellite images. For each identified cumulus cloud, the weather forecasting logic applies interest field tests to determine a score indicating the likelihood of the cumulus cloud forming precipitation and/or lightning in the future within a certain time period. Based on such scores, the weather forecasting logic predicts in which geographic regions the identified cumulus clouds will produce precipitation and/or lighting within during the time period. Such predictions may then be used to provide a weather map thereby providing users with a graphical illustration of the areas predicted to be affected by precipitation within the time period.

  6. Space Weather and Management of Environmental Risks and Hazards

    NASA Astrophysics Data System (ADS)

    Pirjola, R.; Kauristie, K.; Lappalainen, H.

    "Space Weather" is defined as electromagnetic and particle conditions in the space environment that can disturb space-borne and ground-based technological systems (e.g. satellite operation, telecommunication, aviation, electric power transmission) and even endanger human health. Thus, space weather is of great importance to the society since people are dependent on reliable operation of modern technology, interruptions of which may lead to large economical and other losses. Physical processes involved in space weather constitute a complicated chain from the Sun to the Earth's surface. Thus, a full understanding of space weather and the risks it produces requires expertise in many different disciplines of science and technology. Space weather is a new subject among the natural risks and hazards which threaten the society and its infrastructure (although the first observations of ground effects of space weather were already made about 150 years ago). Monitoring systems for the management of other risks, such as floods, forest fires, etc., and for security are, to a great extent, based on satellite observations. Spacecraft and the communication between satellites and the ground are vulnerable to space weather. Thus, besides being a direct risk to technological systems, space weather may also be indirectly adverse to risk management. These two aspects of space weather are considered in a proposal to be submitted to EU's Sixth Framework Programme under the "Aeronautics and Space" priority in the "Global Monitoring for Environment and Security (GMES) / Risk Management" area in March 2004. The proposal coordinated by the Finnish Meteorological Institute with five to ten participating institutes is called SW-RISK ("Space Weather - Risk Indices from Scientific Know-how").

  7. Health physics aspects of processing EBR-I coolant

    SciTech Connect

    Burke, L.L.; Thalgott, J.O.; Poston, J.W. Jr.

    1998-12-31

    The sodium-potassium reactor coolant removed from the Experimental Breeder Reactor Number One after a partial reactor core meltdown had been stored at the Idaho National Engineering and Environmental Laboratory for 40 years. The State of Idaho considered this waste the most hazardous waste stored in the state and required its processing. The reactor coolant was processed in three phases. The first phase converted the alkali metal into a liquid sodium-potassium hydroxide. The second phase converted this caustic to a liquid sodium-potassium carbonate. The third phase solidified the sodium-potassium carbonate into a form acceptable for land disposal. Health physics aspects and dose received during each phase of the processing are discussed.

  8. Detectors and signal processing for high-energy physics

    SciTech Connect

    Rehak, P.

    1981-01-01

    Basic principles of the particle detection and signal processing for high-energy physics experiments are presented. It is shown that the optimum performance of a properly designed detector system is not limited by incidental imperfections, but solely by more fundamental limitations imposed by the quantum nature and statistical behavior of matter. The noise sources connected with the detection and signal processing are studied. The concepts of optimal filtering and optimal detector/amplifying device matching are introduced. Signal processing for a liquid argon calorimeter is analyzed in some detail. The position detection in gas counters is studied. Resolution in drift chambers for the drift coordinate measurement as well as the second coordinate measurement is discussed.

  9. Physical processes in the growth of the continental crust

    NASA Technical Reports Server (NTRS)

    Schubert, G.

    1988-01-01

    Major mechanisms of crustal addition are volcanism and plutonism at plate boundaries and within plate interiors. One approach to deciding if island arc magmatism dominated ancient crustal growth is to assess the rate at which the process has operated in the recent past. The localized addition rates were found to be comparable to present day global rates. One physical observable that was used to constrain models of crustal growth is sea level. A simple physical model was developed to explore the consequences of constant freeboard (the height of the continents above sea level). Global geoid and sea floor topography data were used to identify and study oceanic plateaus and swells that have either continental crustal roots or anomalously thick ocean crusts.

  10. Weathering, Soil Production, and Erosion Across Climatic and Tectonic Gradients

    NASA Astrophysics Data System (ADS)

    Norton, K. P.; Larsen, I. J.

    2014-12-01

    Weathering is one of the fundamental processes that sustain life on our planet. Physical weathering breaks down rock for soil production and chemical weathering is thought to operate as the ultimate long-term negative feedback on atmospheric CO2 concentrations. There remains, however, uncertainty as to the relationship between chemical and physical weathering at very fast rates. If chemical weathering becomes kinetically limited at rapid erosion rates, as has been shown in a number of locations around the globe, then the fastest erosion rates will be associated with reduced chemical weathering. This has led to a debate as to whether tectonically active mountain ranges or rolling plains are the main source of CO2 drawdown through silicate weathering. At the heart of this debate is the dearth of chemical weathering data at fast erosion rates. New cosmogenic nuclide-derived denudation rates from the West Coast of the New Zealand Southern Alps are among the fastest in the world and are linearly correlated with chemical weathering rates. The associated soil production rates reach an order of magnitude faster than previous estimates and far exceed the suggested maximum soil production rate. This suggests that very fast weathering and soil production is possible in such active landscapes and extreme climates. We investigate the controls on these rapid rates with a climate-driven soil production model. At the most basic level, soil production requires chemical weathering of primary minerals to secondary minerals. We apply soil production models with both exponential and hump-shaped dependencies on soil thickness. Mean annual temperature and precipitation are incorporated in the form of a modified Arrhenius equation that controls the maximum soil production rate. When applied to the Southern Alps, the model predicts very rapid soil production that matches the magnitude of the cosmogenic nuclide-derived rates. High annual precipitation in the Southern Alps supports rapid soil generation through increased chemical weathering rates and extensive vegetation cover. When applied more broadly, the climate-dependent soil production model suggests that actively eroding mountain belts may display a linear relationship between weathering and erosion in strongly orographic settings, such as in New Zealand's Southern Alps.

  11. Activities in Teaching Weather

    ERIC Educational Resources Information Center

    Tonn, Martin

    1977-01-01

    Presented is a unit composed of activities for teaching weather. Topics include cloud types and formation, simple weather instruments, and the weather station. Illustrations include a weather chart and instruments. A bibliography is given. (MA)

  12. Exploring clouds, weather, climate, and modeling using bilingual content and activities from the Windows to the Universe program and the Center for Multiscale Modeling of Atmospheric Processes

    NASA Astrophysics Data System (ADS)

    Foster, S. Q.; Johnson, R. M.; Randall, D.; Denning, S.; Russell, R.; Gardiner, L.; Hatheway, B.; Genyuk, J.; Bergman, J.

    2008-12-01

    The need for improving the representation of cloud processes in climate models has been one of the most important limitations of the reliability of climate-change simulations. Now in its third year, the National Science Foundation-funded Center for Multi-scale Modeling of Atmospheric Processes (CMMAP) at Colorado State University is addressing this problem through a revolutionary new approach to representing cloud processes on their native scales, including the cloud-scale interaction processes that are active in cloud systems. CMMAP has set ambitious education and human-resource goals to share basic information about the atmosphere, clouds, weather, climate, and modeling with diverse K-12 and public audiences through its affiliation with the Windows to the Universe (W2U) program at University Corporation for Atmospheric Research (UCAR). W2U web pages are written at three levels in English and Spanish. This information targets learners at all levels, educators, and families who seek to understand and share resources and information about the nature of weather and the climate system, and career role models from related research fields. This resource can also be helpful to educators who are building bridges in the classroom between the sciences, the arts, and literacy. Visitors to the W2U's CMMAP web portal can access a beautiful new clouds image gallery; information about each cloud type and the atmospheric processes that produce them; a Clouds in Art interactive; collections of weather-themed poetry, art, and myths; links to games and puzzles for children; and extensive classroom- ready resources and activities for K-12 teachers. Biographies of CMMAP scientists and graduate students are featured. Basic science concepts important to understanding the atmosphere, such as condensation, atmosphere pressure, lapse rate, and more have been developed, as well as 'microworlds' that enable students to interact with experimental tools while building fundamental knowledge. These resources can be accessed online at no cost by the entire atmospheric science K-12 and informal science education community.

  13. Compact effector optics for processing in limited physical access situations.

    PubMed

    Kuhn, Andreas; Fox, Mahlen D T; French, Paul W; Hettrick, Simon; Hand, Duncan P; Shi, Yi-Wei; Matsuura, Yuji; Miyagi, Mitsunobu; Watkins, Kenneth G; Ireland, Clive L M; Jones, Julian D C

    2003-09-01

    A major advantage of fiber-optic beam delivery in laser materials processing is the ability to guide the laser power to the location where it is needed, leaving the laser itself remote and protected from the process. This is of special importance if the processing is to be performed in a hazardous environment. Particular problems are faced by the nuclear industry where weld repair and surface treatment work are required inside radioactive installations. By use of fiber beam delivery, only part of the delivery system and effector optics become contaminated, but the expensive laser system does not. However, in many cases the region where repair is required is not only radioactive but has only limited physical access, e.g., inside tubes or into corners, which prevents use of standard effector optics. We present a new design to deal with such constraints of a 2-mm outer diameter employing a hollow waveguide and gas shielding. This design is optically characterized and its performance assessed in welding and surface treatment applications. The potential of this compact effector optics in limited physical access situations is clearly demonstrated. PMID:12962387

  14. Compact effector optics for processing in limited physical access situations

    NASA Astrophysics Data System (ADS)

    Kuhn, Andreas; Fox, Mahlen D. T.; French, Paul W.; Hettrick, Simon; Hand, Duncan P.; Shi, Yi-Wei; Matsuura, Yuji; Miyagi, Mitsunobu; Watkins, Kenneth G.; Ireland, Clive L. M.; Jones, Julian D. C.

    2003-09-01

    A major advantage of fiber-optic beam delivery in laser materials processing is the ability to guide the laser power to the location where it is needed, leaving the laser itself remote and protected from the process. This is of special importance if the processing is to be performed in a hazardous environment. Particular problems are faced by the nuclear industry where weld repair and surface treatment work are required inside radioactive installations. By use of fiber beam delivery, only part of the delivery system and effector optics become contaminated, but the expensive laser system does not. However, in many cases the region where repair is required is not only radioactive but has only limited physical access, e.g., inside tubes or into corners, which prevents use of standard effector optics. We present a new design to deal with such constraints of a 2-mm outer diameter employing a hollow waveguide and gas shielding. This design is optically characterized and its performance assessed in welding and surface treatment applications. The potential of this compact effector optics in limited physical access situations is clearly demonstrated.

  15. Weather from the Stratosphere?

    NASA Technical Reports Server (NTRS)

    Baldwin, Mark P.; Thompson, David W. J.; Shuckburgh, Emily F.; Norton, Warwick A.; Gillett, Nathan P.

    2006-01-01

    Is the stratosphere, the atmospheric layer between about 10 and 50 km, important for predicting changes in weather and climate? The traditional view is that the stratosphere is a passive recipient of energy and waves from weather systems in the underlying troposphere, but recent evidence suggests otherwise. At a workshop in Whistler, British Columbia (1), scientists met to discuss how the stratosphere responds to forcing from below, initiating feedback processes that in turn alter weather patterns in the troposphere. The lowest layer of the atmosphere, the troposphere, is highly dynamic and rich in water vapor, clouds, and weather. The stratosphere above it is less dense and less turbulent (see the figure). Variability in the stratosphere is dominated by hemispheric-scale changes in airflow on time scales of a week to several months. Occasionally, however, stratospheric air flow changes dramatically within just a day or two, with large-scale jumps in temperature of 20 K or more. The troposphere influences the stratosphere mainly through atmospheric waves that propagate upward. Recent evidence shows that the stratosphere organizes this chaotic wave forcing from below to create long-lived changes in the stratospheric circulation. These stratospheric changes can feed back to affect weather and climate in the troposphere.

  16. Influence of wheat kernel physical properties on the pulverizing process.

    PubMed

    Dziki, Dariusz; Cacak-Pietrzak, Gra?yna; Mi?, Antoni; Jo?czyk, Krzysztof; Gawlik-Dziki, Urszula

    2014-10-01

    The physical properties of wheat kernel were determined and related to pulverizing performance by correlation analysis. Nineteen samples of wheat cultivars about similar level of protein content (11.2-12.8% w.b.) and obtained from organic farming system were used for analysis. The kernel (moisture content 10% w.b.) was pulverized by using the laboratory hammer mill equipped with round holes 1.0mm screen. The specific grinding energy ranged from 120kJkg(-1) to 159kJkg(-1). On the basis of data obtained many of significant correlations (p?physical properties and pulverizing process of wheat kernel, especially wheat kernel hardness index (obtained on the basis of Single Kernel Characterization System) and vitreousness significantly and positively correlated with the grinding energy indices and the mass fraction of coarse particles (> 0.5mm). Among the kernel mechanical properties determined on the basis of uniaxial compression test only the rapture force was correlated with the impact grinding results. The results showed also positive and significant relationships between kernel ash content and grinding energy requirements. On the basis of wheat physical properties the multiple linear regression was proposed for predicting the average particle size of pulverized kernel. PMID:25328207

  17. The r-process nucleosynthesis: Nuclear physics challenges

    SciTech Connect

    Goriely, S.

    2012-10-20

    About half of the nuclei heavier than iron observed in nature are produced by the socalled rapid neutron capture process, or r-process, of nucleosynthesis. The identification of the astrophysics site and the specific conditions in which the r-process takes place remains, however, one of the still-unsolved mysteries of modern astrophysics. Another underlying difficulty associated with our understanding of the r-process concerns the uncertainties in the predictions of nuclear properties for the few thousands exotic neutron-rich nuclei involved and for which essentially no experimental data exist. The present contribution emphasizes some important future challenges faced by nuclear physics in this problem, particularly in the determination of the nuclear structure properties of exotic neutron-rich nuclei as well as their radiative neutron capture rates and their fission probabilities. These quantities are particularly relevant to determine the composition of the matter resulting from the r-process. Their impact on the r-abundance distribution resulting from the decompression of neutron star matter is discussed.

  18. Influence of chemical weathering and aging of iron oxides on the potential iron solubility of Saharan dust during simulated atmospheric processing

    NASA Astrophysics Data System (ADS)

    Shi, Zongbo; Krom, Michael D.; Bonneville, Steeve; Baker, Alex R.; Bristow, Charlie; Drake, Nick; Mann, Graham; Carslaw, Ken; McQuaid, James B.; Jickells, Tim; Benning, Liane G.

    2011-06-01

    The flux of bioavailable Fe from mineral dust to the surface ocean is controlled not only by the processes in the atmosphere but also by the nature and source of the dust. In this study, we investigated how the nature of Fe minerals in the dust affects its potential Fe solubility (Fepsol) employing traditional and modern geochemical, mineralogical, and microscopic techniques. The chemical and mineralogical compositions, particularly Fe mineralogy, in soil samples as dust precursors collected from North African dust source regions were determined. The Fepsol was measured after 3 days of contact with sulfuric acid at pH 2 to simulate acid processes in the atmosphere. Fepsol of the soil dust samples were compared with calculated predictions of Fepsol based on the amount of individual Fe-bearing minerals present in the samples and Fe solubilities of corresponding standard minerals. The calculated Fepsol deviated significantly from the measured Fepsol of the soil dust samples. We attributed this to the variability in properties of Fe minerals (e.g., size of Fe oxides and heterogeneity of chemical compositions of clay minerals) in soil dusts in comparison to the standard minerals. There were, however, clear relationships between the degree of chemical weathering of North African soils and Fepsol. The Parker index and ratio of ascorbate plus dithionite Fe to total Fe ((FeA+FeD)/FeT) are positively and negatively correlated with Fepsol, respectively. In addition, the ratio of FeA/(FeA+FeD), which decreases with aging of the Fe oxides, was found to be positively correlated with Fepsol in the soil dusts. Overall, our results indicate that there is a significant regional variability in the chemical and Fe mineralogical compositions of dusts across North African sources, as a result of the differences in chemical weathering and aging of Fe oxides. Furthermore, the indices for these weathering processes can provide an estimate of the fraction of Fe which can be solubilized if acid processed in the atmosphere.

  19. Major ion chemistry of the Ganga-Brahmaputra river system: Weathering processes and fluxes to the Bay of Bengal

    SciTech Connect

    Sarin, M.M.; Krishnaswami, S.; Dilli, K.; Somayajulu, B.L.K. ); Moore, W.S. )

    1989-05-01

    The Ganga-Brahmaputra, one of the worlds's largest river systems, is first in terms of sediment transport and fourth in terms of water discharge. A detailed and systematic study of the major ion chemistry of these rivers and their tributaries, as well as the clay mineral composition of the bed sediments has been conducted. The chemistry of the highland rivers are all dominated by carbonate weathering; (Ca + Mg) and HCO{sub 3} account for about 80% of the cations and anions. In the lowland rivers, HCO{sub 3} excess over (Ca + Mg) and a relatively high contribution of (Na + K) to the total cations indicate that silicate weathering and/or contributions from alkaline/saline soils and ground waters could be important sources of major ions to these waters. The chemistry of the Ganga and the Yamuna in the lower reaches is by and large dictated by the chemistry of their tributaries and their mixing proportions. The highland rivers weather acidic rocks, whereas the others flow initially through basic effusives. The Ganga-Brahmaputra river system transports about 130 million tons of dissolved salts to the Bay of Bengal, which is nearly 3% of the global river flux to the oceans. The chemical denudation rates for the Ganga and the Brahmaputra basins are about 72 and 105 tons{center dot}km{sup {minus}2}{center dot}yr{sup {minus}1}, respectively, which are factors of 2 to 3 higher than the global average. The high denudation rate, particularly in the Brahmaputra, is attributable to high relief and heavy rainfall.

  20. Pilot based frameworks for Weather Research Forecasting

    NASA Astrophysics Data System (ADS)

    Ganapathi, Dinesh Prasanth

    The Weather Research Forecasting (WRF) domain consists of complex workflows that demand the use of Distributed Computing Infrastructure (DCI). Weather forecasting requires that weather researchers use different set of initial conditions and one or a combination of physics models on the same set of input data. For these type of simulations an ensemble based computing approach becomes imperative. Most DCIs have local job-schedulers that have no smart way of dealing with the execution of an ensemble type of computational problem as the job-schedulers are built to cater to the bare essentials of resource allocation. This means the weather scientists have to submit multiple jobs to the job-scheduler. In this dissertation we use Pilot-Job based tools to decouple work-load submission and resource allocation therefore streamlining the complex workflows in Weather Research and Forecasting domain and reduce their overall time to completion. We also achieve location independent job execution, data movement, placement and processing. Next, we create the necessary enablers to run an ensemble of tasks bearing the capability to run on multiple heterogeneous distributed computing resources there by creating the opportunity to minimize the overall time consumed in running the models. Our experiments show that the tools developed exhibit very good, strong and weak scaling characteristics. These results bear the potential to change the way weather researchers are submitting traditional WRF jobs to the DCIs by giving them a powerful weapon in their arsenal that can exploit the combined power of various heterogeneous DCIs that could otherwise be difficult to harness owing to interoperability issues.

  1. Physics students' approaches to learning and cognitive processes in solving physics problems

    NASA Astrophysics Data System (ADS)

    Bouchard, Josee

    This study examined traditional instruction and problem-based learning (PBL) approaches to teaching and the extent to which they foster the development of desirable cognitive processes, including metacognition, critical thinking, physical intuition, and problem solving among undergraduate physics students. The study also examined students' approaches to learning and their perceived role as physics students. The research took place in the context of advanced courses of electromagnetism at a Canadian research university. The cognitive science, expertise, physics and science education, instructional psychology, and discourse processes literature provided the framework and background to conceptualize and structure this study. A within-stage mixed-model design was used and a number of instruments, including a survey, observation grids, and problem sets were developed specifically for this study. A special one-week long problem-based learning (PBL) intervention was also designed. Interviews with the instructors participating in the study provided complementary data. Findings include evidence that students in general engage in metacognitive processes in the organization of their personal study time. However, this potential, including the development of other cognitive processes, might not be stimulated as much as it could in the traditional lecture instructional context. The PBL approach was deemed as more empowering for the students. An unexpected finding came from the realisation that a simple exposure to a structured exercise of problem-solving (pre-test) was sufficient to produce superior planning and solving strategies on a second exposure (post-test) even for the students who had not been exposed to any special treatment. Maturation was ruled out as a potential threat to the validity of this finding. Another promising finding appears to be that the problem-based learning (PBL) intervention tends to foster the development of cognitive competencies, particularly physical intuition, even if it was only implemented for a short period of time. Other findings relate to the nature of the cognitive actions and activities that the students engage in when learning to solve electromagnetism problems in a PBL environment for the first time and the tutoring actions that guide students in this context.

  2. Space weather: science and effects

    NASA Astrophysics Data System (ADS)

    Crosby, Norma B.

    2009-03-01

    From the point-of-view of somebody standing outside on a cold winter night looking up at a clear cloudless sky, the space environment seems to be of a peaceful and stable nature. Instead, the opposite is found to be true. In fact the space environment is very dynamic on all spatial and temporal scales, and in some circumstances may have unexpected and hazardous effects on technology and humans both in space and on Earth. In fact the space environment seems to have a weather all of its own - its own “space weather”. Our Sun is definitely the driver of our local space weather. Space weather is an interdisciplinary subject covering a vast number of technological, scientific, economic and environmental issues. It is an application-oriented discipline which addresses the needs of “space weather product” users. It can be truly said that space weather affects everybody, either directly or indirectly. The aim of this paper is to give an overview of what space weather encompasses, emphasizing how solar-terrestrial physics is applied to space weather. Examples of “space weather product” users will be given highlighting those products that we as a civilization are most dependent on.

  3. Framework for Understanding Lenr Processes, Using Conventional Condensed Matter Physics

    NASA Astrophysics Data System (ADS)

    Chubb, Scott R.

    2006-02-01

    Conventional condensed matter physics provides a unifying framework for understanding low-energy nuclear reactions (LENRs) in solids. In the paper, standard many-body physics techniques are used to illustrate this fact. Specifically, the paper shows that formally the theories by Schwinger, Hagelstein, and Chubb and Chubb (C&C), all can be related to a common set of equations, associated with reaction rate and energy transfer, through a standard many-body physics procedure (R-matrix theory). In each case, particular forms of coherence are used that implicitly provide a mechanism for understanding how LENRs can proceed without the emission of high-energy particles. In addition, additional ideas, associated with Conventional Condensed Matter physics, are used to extend the earlier ion band state (IBS) model by C&C. The general model clarifies the origin of coherent processes that initiate LENRs, through the onset of ion conduction that can occur through ionic fluctuations in nanoscale crystals. In the case of PdDx, these fluctuations begin to occur as x → 1 in sub-lattice structures with characteristic dimensions of 60 nm. The resulting LENRs are triggered by the polarization between injected d's and electrons (immediately above the Fermi energy) that takes place in finite-size PdD crystals. During the prolonged charging of PdDx, the applied, external electric field induces these fluctuations through a form of Zener tunneling that mimics the kind of tunneling, predicted by Zener, that is responsible for possible conduction (referred to as Zener-electric breakdown) in insulators. But because the fluctuations are ionic, and they occur in PdD, nano-scale structures, a more appropriate characterization is Zener-ionic breakdown in nano-crystalline PdD. Using the underlying dynamics, it is possible to relate triggering times that are required for the initiation of the effect, to crystal size and externally applied fields.

  4. 3D physical modeling for patterning process development

    NASA Astrophysics Data System (ADS)

    Sarma, Chandra; Abdo, Amr; Bailey, Todd; Conley, Will; Dunn, Derren; Marokkey, Sajan; Talbi, Mohamed

    2010-03-01

    In this paper we will demonstrate how a 3D physical patterning model can act as a forensic tool for OPC and ground-rule development. We discuss examples where the 2D modeling shows no issues in printing gate lines but 3D modeling shows severe resist loss in the middle. In absence of corrective measure, there is a high likelihood of line discontinuity post etch. Such early insight into process limitations of prospective ground rules can be invaluable for early technology development. We will also demonstrate how the root cause of broken poly-line after etch could be traced to resist necking in the region of STI step with the help of 3D models. We discuss different cases of metal and contact layouts where 3D modeling gives an early insight in to technology limitations. In addition such a 3D physical model could be used for early resist evaluation and selection for required ground-rule challenges, which can substantially reduce the cycle time for process development.

  5. Simplified electronic signal processing in the small nuclear physics laboratory

    NASA Astrophysics Data System (ADS)

    DeYoung, P. A.; Peaslee, G. F.

    2005-10-01

    Small nuclear physics laboratories of all kinds traditionally have processed the signals from radiation detectors with a variety of discrete NIM- or CAMAC-based electronic modules. The logic signals associated with signal processing are often passed through gate generators, coincidence modules, fan-in/fan-out modules, delay units, counters, and other assorted logic modules. These multi-component systems generate gates for acquisition systems, gates for specific linear electronics modules (ADCs and TDCs), or measure count rates and dead times. This can involve a significant number of individual modules each of which can be quite costly and each of which provides only limited functions. We describe here an upgrade to our acquisition system where all the needed logic functions are performed in just a single unit: a Universal Logic Module based on a Field Programmable Gate Array (FPGA) from JTEC Corporation. This module also contains flash memory that holds three separate configurations allowing for rapid changes from one electronics configuration to a different one. Both CAMAC and VME versions of the unit are available. The system described here is just one example of the huge variety of functionality that can be programmed into this single module. It can accommodate very complicated circuits and is easily reprogrammed. In the small nuclear physics laboratory the Universal Logic Module can save cost when upgrading systems and reduce the number of instances where one has an insufficient number of channels of a particular function.

  6. Physical anthropology: the search for general processes and principles.

    PubMed

    Lasker, G W

    1970-02-01

    Physical anthropology consists of two interdependent types of study: (1) the biological history of man and (2) general biological processes in man (such as mechanisms of evolution and growth). Popular interest may focus on the former, the fascinating story of the origin of man and of specific people, but the latter affords physical anthropology potential practical value in respect to medicine, dentistry, public health, and population policy. The study of general processes is the study of human beings in particular situations, not for what we can learn about these particular populations but for the sake of generalization about mankind anywhere in comparable situations. This is, of course, the purpose of experimental science in general, but in anthropology the method is usually comparative. Long ago the study of the growth of the two sexes and of children in different countries was started on a comparative basis as was the study of the so-called secular change in adult stature. By 1911 Franz Boas had compared the changes in stature and head form of children of several different immigrant groups in the United States. There have since been comparative studies of the amount and distribution of body fat (but not yet adequate comparative measurements of the relation of tissue components to diet and to diseases). Demographic patterns, inbreeding, outbreeding, and their effects are other general problems. The Human Adaptability Project of the International Biological Program promises studies of human response to heat, cold, altitude, and other conditions on a wide international basis. If supported, these could turn physical anthropology's search in a useful direction. The functional biology of people of even out-of-the-way communities will be compared with each other. These studies can yield general statements concerning human response to types of ecological situation including such sociocultural conditions as those of hunting-gathering tribes and urban slums. PMID:19681215

  7. Innovative Information Technology for Space Weather Research

    NASA Astrophysics Data System (ADS)

    Wang, H.; Qu, M.; Shih, F.; Denker, C.; Gerbessiotis, A.; Lofdahl, M.; Rees, D.; Keller, C.

    2004-05-01

    Solar activity is closely related to the near earth environment -- summarized descriptively as space weather. Changes in space weather have adverse effect on many aspects of life and systems on earth and in space. Real-time, high-quality data and data processing would be a key element to forecast space weather promptly and accurately. Recently, we obtained a funding from US National Science Foundation to apply innovative information technology for space weather prediction. (1) We use the technologies of image processing and pattern recognition, such as image morphology segmentation, Support Vector Machines (SVMs), and neural networks to detect and characterize three important solar activities in real-time: filament eruptions, flares, and emerging flux regions (EFRs). Combining the real time detection with the recent statistical study on the relationship among filament eruptions, flares, EFRs, coronal mass ejections (CMEs), and geomagnetic storms, we are establishing real time report of solar events and automatic forecasting of earth directed CMEs and subsequent geomagnetic storms. (2) We combine state-of-art parallel computing techniques with phase diverse speckle imaging techniques, to yield near real-time diffraction limited images with a cadence of approximately 10 sec. We utilize the multiplicity of parallel paradigms to optimize the calculation of phase diverse speckle imaging to improve calculation speed. With such data, we can monitor flare producing active regions continuously and carry out targeted studies of the evolution and flows in flare producing active regions. (3) We are developing Web based software tools to post our processed data, events and forecasting in real time, and to be integrated with current solar activity and space weather prediction Web pages at BBSO. This will also be a part of Virtual Solar Observatory (VSO) being developed by the solar physics community. This research is supported by NSF ITR program.

  8. CLARA: A Contemporary Approach to Physics Data Processing

    SciTech Connect

    V Gyurjyan, D Abbott, J Carbonneau, G Gilfoyle, D Heddle, G Heyes, S Paul, C Timmer, D Weygand, E Wolin

    2011-12-01

    In traditional physics data processing (PDP) systems, data location is static and is accessed by analysis applications. In comparison, CLARA (CLAS12 Reconstruction and Analysis framework) is an environment where data processing algorithms filter continuously flowing data. In CLARA's domain of loosely coupled services, data is not stored, but rather flows from one service to another, mutating constantly along the way. Agents, performing event processing, can then subscribe to particular data/events at any stage of the data transformation, and make intricate decisions (e.g. particle ID) by correlating events from multiple, parallel data streams and/or services. This paper presents a PDP application development framework based on service oriented and event driven architectures. This system allows users to design (Java, C++, and Python languages are supported) and deploy data processing services, as well as dynamically compose PDP applications using available services. The PDP service bus provides a layer on top of a distributed pub-sub middleware implementation, which allows complex service composition and integration without writing code. Examples of service creation and deployment, along with the CLAS12 track reconstruction application design will be presented.

  9. Guidelines for Automatic Data Processing Physical Security and Risk Management. Federal Information Processing Standards Publication 31.

    ERIC Educational Resources Information Center

    National Bureau of Standards (DOC), Washington, DC.

    These guidelines provide a handbook for use by federal organizations in structuring physical security and risk management programs for their automatic data processing facilities. This publication discusses security analysis, natural disasters, supporting utilities, system reliability, procedural measures and controls, off-site facilities,…

  10. Weathering effects on the structure and reactivity of US coals: Final report, July 15, 1984-July 14, 1987. [Many data

    SciTech Connect

    Meuzelaar, H.L.C.; Hill, G.R.; Yun, Yongseung; Jakab, E.; Windig, W.; Urban, D.; Yon, Kyung Yol; Oestreich, J.; East, J.

    1987-01-01

    This report covers the work performed from July 1984 to July 1987 under the project entitled ''Weathering Effects on Structure and Reactivity of US Coals'' (grant number FG22-84PC70798). The main objectives of the study were to investigate the structural changes in coal during the weathering process as well as to develop a simple, reliable weathering index, which can monitor indirectly the weathering-induced changes in physical and chemical properties. Although there have been numerous publications on structure and reactivity of coal, most data reported in the literature thus far have been obtained on coal samples of uncertain weathering status and therefore need to be interpreted with great caution. Weathering has a profound effect on many important coal properties such as heating value, caking characteristics, acidity, flotability and reactivity in liquefaction, combustion and gasification processes. The objective of developing a weathering index is to predict these coal property changes due to weathering without resorting to real-time measurements or pilot plant runs. This report is comprised of four main chapters: I. Structural Changes due to Weathering; II. Material Balance in Weathering Process; III. Development of a Reliable Weathering Index; and IV. Proposed Weathering Mechanisms. A battery of sophisticated analytical tools and techniques was employed during this study. Pyrolysis mass spectrometry in time-integrated, as well as in time-resolved modes with computer-aided data analysis techniques (such as factor and discriminant analysis), gas chromatography, thermogravimetry/mass spectrometry and solvent extraction were used for determining the role of oxygen during the weathering process. Pyrolysis mass spectrometry, Free Swelling Index and a novel slurry pH technique were employed as weathering indicators. 170 refs.

  11. Contaminants from Cretaceous Black Shale Part 1: Natural weathering processes controlling contaminant cycling in Mancos Shale, southwestern United States, with emphasis on salinity and selenium

    USGS Publications Warehouse

    Tuttle, Michele L.W.; Fahy, Juli W.; Elliott, John G.; Grauch, Richard I.; Stillings, Lisa L.

    2013-01-01

    Soils derived from black shale can accumulate high concentrations of elements of environmental concern, especially in regions with semiarid to arid climates. One such region is the Colorado River basin in the southwestern United States where contaminants pose a threat to agriculture, municipal water supplies, endangered aquatic species, and water-quality commitments to Mexico. Exposures of Cretaceous Mancos Shale (MS) in the upper basin are a major contributor of salinity and selenium in the Colorado River. Here, we examine the roles of geology, climate, and alluviation on contaminant cycling (emphasis on salinity and Se) during weathering of MS in a Colorado River tributary watershed. Stage I (incipient weathering) began perhaps as long ago as 20 ka when lowering of groundwater resulted in oxidation of pyrite and organic matter. This process formed gypsum and soluble organic matter that persist in the unsaturated, weathered shale today. Enrichment of Se observed in laterally persistent ferric oxide layers likely is due to selenite adsorption onto the oxides that formed during fluctuating redox conditions at the water table. Stage II weathering (pedogenesis) is marked by a significant decrease in bulk density and increase in porosity as shale disaggregates to soil. Rainfall dissolves calcite and thenardite (Na2SO4) at the surface, infiltrates to about 1 m, and precipitates gypsum during evaporation. Gypsum formation (estimated 390 kg m−2) enriches soil moisture in Na and residual SO4. Transpiration of this moisture to the surface or exposure of subsurface soil (slumping) produces more thenardite. Most Se remains in the soil as selenite adsorbed to ferric oxides, however, some oxidizes to selenate and, during wetter conditions is transported with soil moisture to depths below 3 m. Coupled with little rainfall, relatively insoluble gypsum, and the translocation of soluble Se downward, MS landscapes will be a significant nonpoint source of salinity and Se to the Colorado River well into the future. Other trace elements weathering from MS that are often of environmental concern include U and Mo, which mimic Se in their behavior; As, Co, Cr, Cu, Ni, and Pb, which show little redistribution; and Cd, Sb, V, and Zn, which accumulate in Stage I shale, but are lost to varying degrees from upper soil intervals. None of these trace elements have been reported previously as contaminants in the study area.

  12. Insight into the Physical and Dynamical Processes that Control Rapid Increases in Total Flash Rate

    NASA Technical Reports Server (NTRS)

    Schultz, Christopher J.; Carey, Lawrence D.; Schultz, Elise V.; Blakeslee, Richard J.; Goodman, Steven J.

    2015-01-01

    Rapid increases in total lightning (also termed "lightning jumps") have been observed for many decades. Lightning jumps have been well correlated to severe and hazardous weather occurrence. The main focus of lightning jump work has been on the development of lightning algorithms to be used in real-time assessment of storm intensity. However, in these studies it is typically assumed that the updraft "increases" without direct measurements of the vertical motion, or specification of which updraft characteristic actually increases (e.g., average speed, maximum speed, or convective updraft volume). Therefore, an end-to-end physical and dynamical basis for coupling rapid increases in total flash rate to increases in updraft speed and volume must be understood in order to ultimately relate lightning occurrence to severe storm metrics. Herein, we use polarimetric, multi-Doppler, and lightning mapping array measurements to provide physical context as to why rapid increases in total lightning are closely tied to severe and hazardous weather.

  13. Geochemical and Isotopic (Sr, U) Tracing of Weathering Processes Controlling the Recent Geochemical Evolution of Soil Solutions in the Strengbach Catchment (Vosges, France)

    NASA Astrophysics Data System (ADS)

    Chabaux, F. J.; Prunier, J.; Pierret, M.; Stille, P.

    2012-12-01

    The characterization of the present-day weathering processes controlling the chemical composition of waters and soils in natural ecosystems is an important issue to predict and to model the response of ecosystems to recent environmental changes. It is proposed here to highlight the interest of a multi-tracer geochemical approach combining measurement of major and trace element concentrations along with U and Sr isotopic ratios to progress in this topic. This approach has been applied to the small granitic Strengbah Catchment, located in the Vosges Mountain (France), used and equipped as a hydro-geochemical observatory since 1986 (Observatoire Hydro-Gochimique de l'Environnement; http://ohge.u-strasbg.fr). This study includes the analysis of major and trace element concentrations and (U-Sr) isotope ratios in soil solutions collected within two soil profiles located on two experimental plots of this watershed, as well as the analysis of soil samples and vegetation samples from these two plots The depth variation of elemental concentration of soil solutions confirms the important influence of the vegetation cycling on the budget of Ca, K, Rb and Sr, whereas Mg and Si budget in soil solutions are quasi exclusively controlled by weathering processes. Variation of Sr, and U isotopic ratios with depth also demonstrates that the sources and biogeochemical processes controlling the Sr budget of soil solutions is different in the uppermost soil horizons and in the deeper ones, and clearly influence by the vegetation cycling.

  14. Major ion chemistry of the Ganga-Brahmaputra river system: Weathering processes and fluxes to the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Sarin, M. M.; Krishnaswami, S.; Dilli, K.; Somayajulu, B. L. K.; Moore, W. S.

    1989-05-01

    The Ganga-Brahmaputra, one of the world's largest river systems, is first in terms of sediment transport and fourth in terms of water discharge. A detailed and systematic study of the major ion chemistry of these rivers and their tributaries, as well as the clay mineral composition of the bed sediments has been conducted. The chemistry of the highland rivers (upper reaches of the Ganga, the Yamuna, the Brahmaputra, the Gandak and the Ghaghra) are all dominated by carbonate weathering; (Ca + Mg) and HCO 3 account for about 80% of the cations and anions. In the lowland rivers (the Chambal, the Betwa and the Ken), HCO 3 excess over (Ca + Mg) and a relatively high contribution of (Na + K) to the total cations indicate that silicate weathering and/or contributions from alkaline/saline soils and groundwaters could be important sources of major ions to these waters. The chemistry of the Ganga and the Yamuna in the lower reaches is by and large dictated by the chemistry of their tributaries and their mixing proportions. Illite is the dominant clay mineral (about 80%) in the bedload sediments of the highland rivers. Kaolinite and chlorite together constitute the remaining 20% of the clays. In the Chambal, Betwa and Ken, smectite accounts for about 80% of the clays. This difference in the clay mineral composition of the bed sediments is a reflection of the differences in the geology of their drainage basins. The highland rivers weather acidic rocks, whereas the others flow initially through basic effusives. The Ganga-Brahmaputra river system transports about 130 million tons of dissolved salts to the Bay of Bengal, which is nearly 3% of the global river flux to the oceans. The chemical denudation rates for the Ganga and the Brahmaputra basins are about 72 and 105 tons· km -· yr -1, respectively, which are factors of 2 to 3 higher than the global average. The high denudation rate, particularly in the Brahmaputra, is attributable to high relief and heavy rainfall.

  15. Impact of physical permafrost processes on hydrological change

    NASA Astrophysics Data System (ADS)

    Hagemann, Stefan; Blome, Tanja; Beer, Christian; Ekici, Altug

    2015-04-01

    Permafrost or perennially frozen ground is an important part of the terrestrial cryosphere; roughly one quarter of Earth's land surface is underlain by permafrost. As it is a thermal phenomenon, its characteristics are highly dependent on climatic factors. The impact of the currently observed warming, which is projected to persist during the coming decades due to anthropogenic CO2 input, certainly has effects for the vast permafrost areas of the high northern latitudes. The quantification of these effects, however, is scientifically still an open question. This is partly due to the complexity of the system, where several feedbacks are interacting between land and atmosphere, sometimes counterbalancing each other. Moreover, until recently, many global circulation models (GCMs) and Earth system models (ESMs) lacked the sufficient representation of permafrost physics in their land surface schemes. Within the European Union FP7 project PAGE21, the land surface scheme JSBACH of the Max-Planck-Institute for Meteorology ESM (MPI-ESM) has been equipped with the representation of relevant physical processes for permafrost studies. These processes include the effects of freezing and thawing of soil water for both energy and water cycles, thermal properties depending on soil water and ice contents, and soil moisture movement being influenced by the presence of soil ice. In the present study, it will be analysed how these permafrost relevant processes impact projected hydrological changes over northern hemisphere high latitude land areas. For this analysis, the atmosphere-land part of MPI-ESM, ECHAM6-JSBACH, is driven by prescribed SST and sea ice in an AMIP2-type setup with and without the newly implemented permafrost processes. Observed SST and sea ice for 1979-1999 are used to consider induced changes in the simulated hydrological cycle. In addition, simulated SST and sea ice are taken from a MPI-ESM simulation conducted for CMIP5 following the RCP8.5 scenario. The corresponding simulations with ECHAM6-JSBACH are used to assess differences in projected hydrological changes induced by the permafrost relevant processes.

  16. Physical Processes Involved In Yellow Sea Solitary Waves

    NASA Astrophysics Data System (ADS)

    Warn-Varnas, A.; Chin-Bing, S.; King, D.; Lamb, K.; Hawkins, J.; Teixeira, M.

    The study area is located south of the Shandong peninsula. In this area, soliton gener- ation and propagation studies are per formed with the Lamb(1994) model. The model is nonhydrostatic and is formulated in 2 1/2 dimensions for terrain following c oordi- nates. In the area, 20 to 30 m topographic variations over distances of 10 to 20 km are found to occur in the digit al atlas of Choi (1999). The area is shallow with maximum depths ranging from 40 m to 70 m. Along the southern boundary of the region the semi-diurnal tidal strength magnitude varies from .6 m/sec to 1.2 m/sec, Fang(1994). We show that, for sum mer conditions, the existing physical processes associated with the semi-diurnal tidal flow over the topographic variations , in the shelfbreak region, lead to the formation of internal bores in the model simulations. Through acting phys- ical proce sses, the internal bores propagate on and off the shelf. A disintegration process of internal bores into solitary waves occ urs through frequency and ampli- tude dispersion. SAR observations of the area show images containing six events con- sisting of internal bores and solitary waves that travel in a well-defined direction for two and a half days. The origin of the trains appeared to be at a point along a steep topo graphic drop. The SAR observations are used for guiding and tuning the model simulations, by comparing spectra of observed and modeled wavelengths. The tuned model yields wavelengths that are within a factor of 2 of the SAR data. The modeled amp litudes are within a factor of 2 of amplitudes obtained with a two-layer model and the SAR data The signature on the acoustical field of ongoing physical processes through the interaction of the resultant oceanic struct ure with the acoustical field is pursued. Internal bore and solitary wave structures interact with the acoustic field. A re distribution of acoustical energy to higher acoustical modes occurs at some fre- quencies. Mode decomposition of the acoustic fields indicate that mode conversions necessary for anomalous signal losses are present. The acoustical process of redistr ibuting acoustical energy to higher modes is coupled to oceanographic processes as- sociated with a propagating solitary wave .

  17. Framework for Understanding LENR Processes, Using Ordinary Condensed Matter Physics

    NASA Astrophysics Data System (ADS)

    Chubb, Scott

    2005-03-01

    As I have emphasizedootnotetextS.R. Chubb, Proc. ICCF10 (in press). Also, http://www.lenr-canr.org/acrobat/ChubbSRnutsandbol.pdf http://www.lenr-canr.org/acrobat/ChubbSRnutsandbol.pdf, S.R. Chubb, Trans. Amer. Nuc. Soc. 88 , 618 (2003)., in discussions of Low Energy Nuclear Reactions(LENRs), mainstream many-body physics ideas have been largely ignored. A key point is that in condensed matter, delocalized, wave-like effects can allow large amounts of momentum to be transferred instantly to distant locations, without any particular particle (or particles) acquiring high velocity through a Broken Gauge Symmetry. Explicit features in the electronic structure explain how this can occur^1 in finite size PdD crystals, with real boundaries. The essential physics^1 can be related to standard many-body techniquesootnotetextBurke,P.G. and K.A. Berrington, Atomic and Molecular Processes:an R matrix Approach (Bristol: IOP Publishing, 1993).. In the paper, I examine this relationship, the relationship of the theory^1 to other LENR theories, and the importance of certain features (for example, boundaries^1) that are not included in the other LENR theories.

  18. Measurement of physical properties of coal liquids under process conditions

    SciTech Connect

    Oswald, G.E.; Youngblood, E.L.; Hightower, J.R.; Cochran, H.D.

    1980-01-01

    Instrumentation has been developed for measurement of physical properties (viscosity and density) of coal liquids and slurries under conditions typical of those found in coal liquefaction processes such as SRC, H-Coal, and EDS. The instruments are being operated in a flow system designed for slurry rates up to 1 g/s at 810 K and 31 MPa pressure. A capillary tube viscometer and a Norcross falling ring viscometer are used for viscosity measurement. Thus far rheograms (shear rate vs shear stress diagrams) have been determined for 35 wt % Illinois No. 6 coal (-170 mesh) in SRC-I recycle solvent at 13.9 MPa (2000 psig) for the temperature range of 400 to 700 K. A commercially available gamma radiation absorption instrument has been modified for the operating conditions required and is being used for density measurements. Instruments for measurement of thermal conductivity and heat capacity of coal liquids have been designed for future installation in the facility.

  19. Convection in the Physical Vapor Transport Process-I: Thermal

    NASA Technical Reports Server (NTRS)

    Duval, Walter M. B.

    1994-01-01

    The effects of convection on diffusive-convective physical vapor transport process are examined computationally. We analyze conditions ranging from typical laboratory conditions to conditions achievable only in a low gravity environment. This corresponds to thermal Rayleigh numbers Ra, ranging from 1.80 x 10 to 1.92 x 10(exp 6). Our results indicate that the effect of the sublimation and condensation fluxes at the boundaries is to increase the threshold of instability. For typical ground based conditions, time dependent oscillatory convection can occur. This results in unsteady transport, and non- uniform temperature and concentration gradients at the crystal interface. Spectral analysis of the flow field shows parametric regions exhibiting both an oscillatory approach to steady state and a chaotic transient to a periodic state. Low gravity conditions stabilize the flow field. Convective effects are effectively reduced, thus resulting in uniform temperature and concentration gradients at the interface, a desirable condition for crystal growth.

  20. Convection in the Physical Vapor Transport Process. 1; Thermal

    NASA Technical Reports Server (NTRS)

    Duval, Walter M. B.

    1994-01-01

    The effects of convection on diffusive-convective physical vapor transport process are examined computationally. We analyze conditions ranging from typical laboratory conditions to conditions achievable only in a low gravity environment. This corresponds to thermal Rayleigh numbers Ra(sub tau) ranging from 1.80 x 10 to 1.92 x 10(exp 6). Our results indicate that the effect of the sublimation and condensation fluxes at the boundaries is to increase the threshold of instability. For typical ground based conditions, time dependent oscillatory convection can occur. This results in unsteady transport, and non-uniform temperature and concentration gradients at the crystal interface. Spectral analysis of the flow field shows parametric regions exhibiting both an oscillatory approach to steady state and a chaotic transient to a periodic state. Low gravity conditions stabilize the flow field. Convective effects are effectively reduced, thus resulting in uniform temperature and concentration gradients at the interface, a desirable condition for crystal growth.

  1. Absorption and emission by atmospheric gases - The physical processes

    NASA Astrophysics Data System (ADS)

    McCartney, E. J.

    This book has been written for those who wish to understand better the processes of absorption and emission and their manifold effects. Persons having such interests or needs are the workers in meteorology, atmospheric physics, aerospace surveillance, and air-pollution control. Introductory ideas and useful facts are presented, taking into account an overview of absorption and emission, the electromagnetic spectrum and its parameters, the quantization of energy, the molecular origins of spectra, and the laws of blackbody radiation. Gas properties are considered along with thermodynamics, molecular kinetics, quantized energy states and population, molecular internal energies, spectra of energy transitions, and parameters of line and band absorption. Attention is given to molecular dipole moments, rotational energy and transitions, vibrational energy and transitions, and absorption and emission data.

  2. Honeycomb Weathering of Limestone Formations

    USGS Multimedia Gallery

    Honeycomb weathering of sandstone located on the shores of Puget Sound occurs when expanding salt crystals break fragments of rock, creating a small hole that becomes larger as the process repeats itself over time....

  3. Role of the subgrid-scale physical processes in supermodelling

    NASA Astrophysics Data System (ADS)

    Yano, J.

    2011-12-01

    The basic ides of supermodelling is in overcoming deficits of existing models by combining them together to improve our ability of climate simulations and prediction. However, in order to exploit this method better, we have to pay special attention to the common defects of the current climate models. Representation of subgrid-scale physical processes is such a particular example. . The present talk presents the author's point of view on representation of subgrid-scale processes in the above general question in mind. The focus of the talk will be on interplay between traditional parameterizations and recently proposed superparameterization (also often called "multiscale modelling"), but it also covers the issues of downscaling as well as possibilities of introducing mesh-refinement approaches into the context of subgrid-scale modelling. The author's main perspective is that the subgrid-scale parameterization should not be considered as a distinguished approach in contrast to explicit (more direct) modelling, such as superparameterization, but a hierarchy of modelling approaches should be constructed by taking various intermediate approaches. The mass-flux convection parameterization is taken as an example in order to make this point. It will be shown that at the most basic level, the mass-flux parameterization is equivalent to a finite-volume numerical approach, though various additional approximations and hypotheses must be introduced in order to arrive at a classical mass-flux parameterization. At the mathematical level, the multiresolution analysis based on wavelet provides a basic source of inspirations for developing this general perspective. From this perspective, the issue of parameterization is considered as "compression" of a full explicit model in the same sense as the wavelet can be used for the image compression. This perspective also leads to a concept of compression of physics. Compression of cloud microphysics would be the most urgent issue considering its vast complexity as well as its crucial importance in climate feedbacks.

  4. Public Awareness of Space Weather

    NASA Astrophysics Data System (ADS)

    Lanzerotti, Louis J.

    2009-08-01

    As society increasingly relies on space-based infrastructure for communication and national security, there is a growing need to improve public awareness of the risks space weather poses. The National Space Weather Program (NSWP) should consider this need as it develops new strategic plans. The 2006 “Report of the Assessment Committee for the National Space Weather Program” (http://www.ofcm.gov/r24/fcm-r24.htm) continues to guide this important national program, which aims to improve space weather forecasting services and reduce technological vulnerabilities. NSWP, under the auspices of the Office of the Federal Coordinator for Meteorology (OFCM), is coordinated by the NSWP Council, which consists of eight federal agencies. This council, through its Committee for Space Weather, is in the process of formulating new Strategic and Implementation plans for the NSWP using recommendations from the Assessment Committee.

  5. Twelve testable hypotheses on the geobiology of weathering.

    PubMed

    Brantley, S L; Megonigal, J P; Scatena, F N; Balogh-Brunstad, Z; Barnes, R T; Bruns, M A; Van Cappellen, P; Dontsova, K; Hartnett, H E; Hartshorn, A S; Heimsath, A; Herndon, E; Jin, L; Keller, C K; Leake, J R; McDowell, W H; Meinzer, F C; Mozdzer, T J; Petsch, S; Pett-Ridge, J; Pregitzer, K S; Raymond, P A; Riebe, C S; Shumaker, K; Sutton-Grier, A; Walter, R; Yoo, K

    2011-03-01

    Critical Zone (CZ) research investigates the chemical, physical, and biological processes that modulate the Earth's surface. Here, we advance 12 hypotheses that must be tested to improve our understanding of the CZ: (1) Solar-to-chemical conversion of energy by plants regulates flows of carbon, water, and nutrients through plant-microbe soil networks, thereby controlling the location and extent of biological weathering. (2) Biological stoichiometry drives changes in mineral stoichiometry and distribution through weathering. (3) On landscapes experiencing little erosion, biology drives weathering during initial succession, whereas weathering drives biology over the long term. (4) In eroding landscapes, weathering-front advance at depth is coupled to surface denudation via biotic processes. (5) Biology shapes the topography of the Critical Zone. (6) The impact of climate forcing on denudation rates in natural systems can be predicted from models incorporating biogeochemical reaction rates and geomorphological transport laws. (7) Rising global temperatures will increase carbon losses from the Critical Zone. (8) Rising atmospheric P(CO2) will increase rates and extents of mineral weathering in soils. (9) Riverine solute fluxes will respond to changes in climate primarily due to changes in water fluxes and secondarily through changes in biologically mediated weathering. (10) Land use change will impact Critical Zone processes and exports more than climate change. (11) In many severely altered settings, restoration of hydrological processes is possible in decades or less, whereas restoration of biodiversity and biogeochemical processes requires longer timescales. (12) Biogeochemical properties impart thresholds or tipping points beyond which rapid and irreversible losses of ecosystem health, function, and services can occur. PMID:21231992

  6. Indirect consequences of extreme weather and climate events and their associations with physical health in coastal Bangladesh: a cross-sectional study

    PubMed Central

    Beier, Dominik; Brzoska, Patrick; Khan, Mobarak Hossain

    2015-01-01

    Background Bangladesh is one of the countries in the world which is most prone to natural disasters. The overall situation is expected to worsen, since extreme weather and climate events (EWCE) are likely to increase in both frequency and intensity. Indirect consequences caused in the events’ aftermath widen the range of possible adverse health outcomes. Objective To assess the association of indirect consequences of EWCE and physical health. Design We used recent cross-sectional self-reported data from 16 coastal villages in Bangladesh. A total of 980 households were surveyed using a structured questionnaire. The outcome of physical health was categorized into three groups, reflecting the severity of reported diseases by the respective source of treatment as a proxy variable (hospital/clinic for severe disease, other source/no treatment for moderate disease, and no disease). The final statistical analysis was conducted using multinomial logistic regression. Results Severe diseases were significantly associated with drinking water from open sources [odds ratio (OR): 4.26, 95% confidence interval (CI): 2.25–8.09] and tube wells (OR: 2.39, 95% CI: 1.43–4.01), moderate harm by river erosion (OR: 6.24, 95% CI: 2.76–14.11), food scarcity (OR: 1.98, 95% CI: 1.16–3.40), and the perception of increased employment problems (OR: 2.19, 95% CI: 1.18–4.07). Moderate diseases were significantly associated with moderate harm by river erosion (OR: 2.65, 95% CI: 1.28–5.48) and fully experienced food scarcity (OR: 1.75, 95% CI: 1.16–2.63). For both categories, women and the elderly had higher chances for diseases. Conclusions Indirect consequences of EWCE were found to be associated with adverse health outcomes. Basic needs such as drinking water, food production, and employment opportunities are particularly likely to become threatened by EWCE and, thus, may lead to a higher likelihood of ill-health. Intervention strategies should concentrate on protection and provision of basic needs such as safe drinking water and food in the aftermath of an event. PMID:26477878

  7. Physical processes effecting the baryonic matter content of the Universe

    NASA Astrophysics Data System (ADS)

    Panayotova, Mariana

    2015-01-01

    We have discussed physical processes effecting the generation of the matter content of the Universe. First we have studied the processes effecting Big Bang Nucleosynthesis during which the chemical content of the baryonic component of the Universe was produced. We have provided detail numerical analysis of the BBN production of ^4He, Y_p, in the presence of ?_e ? ?_s neutrino oscillations, effective after electron neutrino decoupling. We have accounted for all known effects of neutrino oscillations on cosmological nucleosyntesis. We have obtained cosmological bounds corresponding to ? Y_p/Y_p= 5.2 % in correspondance with the recently found higher uncertainty in ^4He. Iso-helium contours for ? Y_p/Y_p > 5% and population of the ?_s state ? N_s = 0; 0.5; 0.7; 0.9, both for resonant and non-resonant oscillations have been calculated. Next we have studied the processes effecting the formation of the baryon content of the Universe. We have investigated a baryogenesis model based on Affleck and Dine baryogenesis scenario, Scalar Field Condensate (SFC) baryogenesis model. We have provided precise numerical analysis of the SFC baryogenesis model numerically accounting for the particle creation processes by the time varying scalar field. We have numerically obtained the dependence of the field and baryon charge evolution and their final values on the model's parameters, namely: the gauge coupling constant ?, the Hubble constant during inflation H_I, the mass of the field m and the self coupling constants ?_i. We have found the range of the model parameters for which a baryon asymmetry value close to the observed one can be generated.

  8. Weathering crusts on peridotite

    NASA Astrophysics Data System (ADS)

    Bucher, Kurt; Stober, Ingrid; Mller-Sigmund, Hiltrud

    2015-05-01

    Chemical weathering of dark-green massive peridotite, including partly serpentinized peridotite, produces a distinct and remarkable brown weathering rind when exposed to the atmosphere long enough. The structure and mineral composition of crusts on rocks from the Ronda peridotite, Spain, have been studied in some detail. The generic overall weathering reaction serpentinized peridotite + rainwater = weathering rind + runoff water describes the crust-forming process. This hydration reaction depends on water supply from the outcrop surface to the reaction front separating green peridotite from the brown crust. The reaction pauses after drying and resumes at the front after wetting. The overall net reaction transforms olivine to serpentine in a volume-conserving replacement reaction. The crust formation can be viewed as secondary serpentinization of peridotite that has been strongly altered by primary hydrothermal serpentinization. The reaction stoichiometry of the crust-related serpentinization is preserved and reflected by the composition of runoff waters in the peridotite massif. The brown color of the rind is caused by amorphous Fe(III) hydroxide, a side product from the oxidation of Fe(II) released by the dissolution of fayalite component in olivine.

  9. Adaptive Numerical Algorithms in Space Weather Modeling

    NASA Technical Reports Server (NTRS)

    Toth, Gabor; vanderHolst, Bart; Sokolov, Igor V.; DeZeeuw, Darren; Gombosi, Tamas I.; Fang, Fang; Manchester, Ward B.; Meng, Xing; Nakib, Dalal; Powell, Kenneth G.; Stout, Quentin F.; Glocer, Alex; Ma, Ying-Juan; Opher, Merav

    2010-01-01

    Space weather describes the various processes in the Sun-Earth system that present danger to human health and technology. The goal of space weather forecasting is to provide an opportunity to mitigate these negative effects. Physics-based space weather modeling is characterized by disparate temporal and spatial scales as well as by different physics in different domains. A multi-physics system can be modeled by a software framework comprising of several components. Each component corresponds to a physics domain, and each component is represented by one or more numerical models. The publicly available Space Weather Modeling Framework (SWMF) can execute and couple together several components distributed over a parallel machine in a flexible and efficient manner. The framework also allows resolving disparate spatial and temporal scales with independent spatial and temporal discretizations in the various models. Several of the computationally most expensive domains of the framework are modeled by the Block-Adaptive Tree Solar wind Roe Upwind Scheme (BATS-R-US) code that can solve various forms of the magnetohydrodynamics (MHD) equations, including Hall, semi-relativistic, multi-species and multi-fluid MHD, anisotropic pressure, radiative transport and heat conduction. Modeling disparate scales within BATS-R-US is achieved by a block-adaptive mesh both in Cartesian and generalized coordinates. Most recently we have created a new core for BATS-R-US: the Block-Adaptive Tree Library (BATL) that provides a general toolkit for creating, load balancing and message passing in a 1, 2 or 3 dimensional block-adaptive grid. We describe the algorithms of BATL and demonstrate its efficiency and scaling properties for various problems. BATS-R-US uses several time-integration schemes to address multiple time-scales: explicit time stepping with fixed or local time steps, partially steady-state evolution, point-implicit, semi-implicit, explicit/implicit, and fully implicit numerical schemes. Depending on the application, we find that different time stepping methods are optimal. Several of the time integration schemes exploit the block-based granularity of the grid structure. The framework and the adaptive algorithms enable physics based space weather modeling and even forecasting.

  10. Physical Education for Children: A Focus on the Teaching Process.

    ERIC Educational Resources Information Center

    Logsdon, Bette J.; And Others

    This book is written for the physical education teacher at the elementary school level. In its ten chapters the following topics are covered: (1) an historical and philosophical examination of physical education in the American schools; (2) changes and new goals in the field of physical education; (3) concepts of learning and development in the

  11. Physical Education Resources, Class Management, and Student Physical Activity Levels: A Structure-Process-Outcome Approach to Evaluating Physical Education Effectiveness

    ERIC Educational Resources Information Center

    Bevans, Katherine B.; Fitzpatrick, Leslie-Anne; Sanchez, Betty M.; Riley, Anne W.; Forrest, Christopher

    2010-01-01

    Background: This study was conducted to empirically evaluate specific human, curricular, and material resources that maximize student opportunities for physical activity during physical education (PE) class time. A structure-process-outcome model was proposed to identify the resources that influence the frequency of PE and intensity of physical

  12. Physical processes in grid control gas discharge device Tacitron

    NASA Astrophysics Data System (ADS)

    Arefiev, Alexander; Vereschagin, Nicolay; Kruglov, Sergey

    2003-10-01

    Physical processes in grid control gas discharge device Tacitron Arefjev A.S., Vereschagin N.M., Kruglov S. A. Radioengineering Academy, Ryazan, Russia Nowdays pulsed power units is getting widely used for cleaning biogas and water. Their parameters and dimension defines by the current commutator, which is used as a switch for interrupting the current in the circuit. Experimental investigations have been carried out to find out the propeties of the one type of the current commutator - the so-called tacitron. It has specific construction of the control grid ,which enables to control the moment of the discharge plasma distinguish and consequently a tacitron has ability to distinguish the discharge, e.i. to interrupt the current, flowing through the device. The grid of a tacitron is constructed of small-mesh metal. The dimension of the small-mesh cell must be compare with Debay radius at the proper discharge conditions. It is stipulated by the fact that if the dimensions of the grid cell are compare with Debay radius then ionic sheaths on the negative electrode as if 'overlap' each other. Then if to supply the controlling impulse to the grid of the tacitron one can ensure interrupting the current through the tacitron. Thus a tacitron is full controlling discharge current commutator. There has been performed experimental investigation of the process of the current interruption.(distinguishing of the gas discharge), taking place in the discharge space between the anode and the cathode of the tacitron. The outcomes of experiments show that the process of the distinguishing may be divided on 4 stages, which differ one from another by elementary processes, going on there : - delay of the distinguishing of the discharge; - so-called 'slow ' stage; - decay of plasma inside the anode - grid gap; - decay of plasma inside the cathode - grid gap. The whole duration of the process of the discharge distinguishing equals mostly the second and the third stages together. The duration of all stages of the distinguishing depends on: - pressure of the gas; - magnitude of the interrupting current (the concentration of electrons and ions in the discharge space); - magnitude of the voltage on the anode and grid; - sort of the filling gas - type of the load. According to the results of the investigation some recomendations on the operating of the tacitron in pulse power units were done.

  13. Linking stochastic sediment transport to physical processes (Invited)

    NASA Astrophysics Data System (ADS)

    Jerolmack, D. J.; Martin, R.; Paola, C.; Reitz, M. D.; Schumer, R.

    2010-12-01

    Intermittent transport is the rule rather than the exception in sedimentary systems. Avalanching dynamics in granular flows is known to produce stochastic transport fluctuations over a wide range of scales - for example, the well known power-law distributions of landslide magnitudes. Similar stochastic dynamics can occur in multi-phase flows, e.g., bedload transport in rivers. A generalized theoretical framework for understanding stochastic transport is lacking. A pragmatic alternative is the stochastic processes approach: using (fractional) advection-diffusion equations, conditioned with measured statistics from a real system, to make future predictions about transport. Linking the macroscopic statistics described by such models to the microscopic physics of sediment transport will require a new statistical mechanics approach. We propose to begin by delineating generic categories of transport mechanics - universality classes - and determining their statistical signatures through theory and experiment. A first separation may be drawn between periodic and aperiodic transport fluctuations. Periodic transport fluctuations have been observed in both sand piles and river delta experiments, and appear to arise under conditions of a well-defined transport threshold (e.g., an angle of repose) and limited dissipation. Under these conditions, inertia overwhelms system heterogeneity and gives rise to periodic oscillations having a characteristic magnitude. Aperiodic transport fluctuations often imply a strong control of system heterogeneity, and/or significant dissipation or friction capable of breaking up sediment pulses. For example, varying soil properties give rise to a range of critical failure slopes for landslides. Transitions in the dominant transport process from small to large time or space scales are expected to result in transitions in scaling. Bedload transport is super-diffusive at short timescales because of correlated motion due to particle momentum. At long timescales, however, particles spend more time at rest than they do in motion and, dispersion of grains becomes sub-diffusive. In this talk we will outline the origins of thresholds, correlations and rest periods that arise in sediment transport, and their expected macroscopic scaling. We synthesize recent experiments to show how length and time scales imparted by the physical system can force a transition in transport statistics.

  14. A New Approach to Understanding Brown Dwarf Weather

    NASA Astrophysics Data System (ADS)

    Morley, Caroline

    2014-10-01

    Over 130 HST orbits and 3000 Spitzer hours have been dedicated to observing variability in the emission of brown dwarfs, but we do not yet understand the physical processes that cause brown dwarf weather. The aim of the proposed work is to build the modeling tools to turn brown dwarf light curves into constraints on their atmospheric physics. Light curves of variable brown dwarfs are not simple sinusoids, but show spectral dependence in both amplitude and phase. Many objects exhibit evolution in the amplitude or shape of the light curve from one observation to another, indicating evolution of weather patterns. These complexities mean that while the two likely causes of variability--patchy clouds and temperature perturbations--should have distinct spectral signatures, the data are proving challenging to explain with simple prescriptions. Our tool to understand this extrasolar weather is to use a retrieval technique to extract the physical parameters that cause brown dwarf variability, directly from brown dwarf spectra. Using this tool with the information-rich HST data, we probe the temperature and cloud structure in multiple spatial dimensions as well as the time-evolution of these structures. These constraints provide crucial information for the development of atmospheric dynamical models, currently in their infancy for brown dwarfs. The retrieval technique we propose will allow us to leave the confines of pre-calculated grid models and measure the causes of brown dwarf weather directly from spectra. This tool will provide the information necessary to understand the atmospheric physics underlying warm substellar weather, decades before we can study weather on exoplanets.

  15. Forecasting the Weather.

    ERIC Educational Resources Information Center

    Bollinger, Richard

    1984-01-01

    Presents a computer program which predicts the weather based on student input of such weather data as wind direction and barometric pressure. Also provides procedures for several hands-on, weather-related activities. (JN)

  16. Weather in the News.

    ERIC Educational Resources Information Center

    Markle, Sandra

    1989-01-01

    A discussion of TV weather forecasting introduces this article which features several hands-on science activities involving observing, researching, and experimenting with the weather. A reproducible worksheet on the reliability of weather forecasts is included. (IAH)

  17. Winter Weather Checklists

    MedlinePLUS

    ... Health Matters What's New Preparation & Planning Disasters & Severe Weather Earthquakes Extreme Heat Floods Hurricanes Landslides Tornadoes Tsunamis ... Weather Information on Specific Types of Emergencies Winter Weather Checklists Language: English Español (Spanish) Recommend on Facebook ...

  18. Physical Processes Shaping Sahelian Heat Waves: Analysis Of Selected Case Studies

    NASA Astrophysics Data System (ADS)

    Guichard, F.; Barbier, J.; Bouniol, D.; Couvreux, F.; Geoffroy, O.; Roehrig, R.; Tomasini, M.; Leauthaud, C.; Kergoat, L.

    2014-12-01

    In the Sahel, the temperature is extremely high in Spring, with typical monthly-mean values of daily minimum, maximum and mean temperature of respectively 30, 40 and 35°C (Guichard et al. J. Hydrology 2009). Therefore, heat waves occurring at this period of the year can have particularly severe repercussions. Furthermore, current climate projections suggest that their frequency and intensity may increase in the future. Numerous heat-wave studies have focused on the mid-latitudes, but almost none on the Sahel. However, the specificities of the Sahelian climate imply that the mechanisms at play in this semi-arid region differ from those previously identified in the mid-latitudes. The influence of the Saharan Heat low is strong in this region; the soil is mostly dry in Spring, and soil-moisture feedbacks identified in mid-latitude studies are therefore unlikely to operate during Sahelian heat waves at this time of year. The present study is carried out within the ACASIS ANR project, which focuses on these Sahelian events. Here, we make use of complementary datasets (SYNOP and soundings data, high-frequency weather and flux stations, satellite data, meteorological reanalyses), together with models, to explore the importance of physical processes during a few selected heat-wave cases chosen from 2006 to 2014. These events are first identified with commonly-used indexes and the associated large-scale circulations are documented. The time-sequences of the surface energy budget and boundary layer diurnal and nocturnal states are then presented, with estimations of non-negligible cloud and aerosol effects on surface radiative fluxes. Our results imply in particular a major importance of the monsoon flow during the night, which induces dramatic changes in the surface-atmosphere couplings, namely a sharp increase of the net longwave flux involving water vapour radiative properties, accompanied by a strong night-time warming. These processes are diversely captured by models and reanalyses.

  19. Weathering instability and landscape evolution

    NASA Astrophysics Data System (ADS)

    Phillips, Jonathan D.

    2005-04-01

    The argument in this paper is that the fundamental control on landscape evolution in erosional landscapes is weathering. The possibility of and evidence for instability in weathering at four scales is examined. The four scales are concerned with weathering processes, allocation of weathered products, the interrelations of weathering and denudation, and the topographic and isostatic responses to weathering-limited denudation (the regolith, hillslope, landscape unit, and landscape scales, respectively). The stability conditions for each model, and the circumstances under which the models themselves are relevant, are used to identify scale-related domains of stability and instability. At the regolith scale, the interactions among weathering rates, resistance, and moisture are unstable, but there are circumstancesover long timescales and where weathering is well advancedunder which the instability is irrelevant. At the hillslope scale, the system is stable when denudation is transport rather than weathering limited and where no renewal of exposure via regolith stripping occurs. At the level of landscape units, the stability model is based entirely on the mutual reinforcements of weathering and erosion. While this should generally lead to instability, the model would be stable where other, external controls of both weathering and erosion rates are stronger than the weathering-erosion feedbacks. At the broadest landscape scale, the inclusion of isostatic responses destabilizes erosion-topography-uplift relationships. Thus, if the spatial or temporal scale is such that isostatic responses are not relevant, the system may be stable. Essentially, instability is prevalent at local spatial scales at all but the longest timescales. Stability at intermediate spatial scales is contingent on whether weathering-erosion feedbacks are strong or weak, with stability being more likely at shorter and less likely at longer timescales. At the broadest spatial scales, instability is likely; although stability may be present at intermediate temporal scales if weathering-erosion feedbacks are weak. The distinction is important because stability is associated with convergent evolution whereby the effects of initial variations or disturbances are reduced over time as the landscape converges toward a stable equilibrium state. Instability, by contrast, indicates divergent evolution, increasing differentiation over time, and the persistence and growth of disturbance effects and initial variations.

  20. Carbonate Beaches: A Balance Between Biological and Physical Processes

    NASA Astrophysics Data System (ADS)

    Nairn, R.; Risk, M.

    2004-12-01

    Carbonate beaches are a unique example of the interaction between biological processes, creating the sediments, and physical processes, moving and often removing the sediments. On the sediment supply side, carbonate sediments are born, not made. They exist in dynamic equilibrium between production and destruction. Following the creation of carbonate sediment in coral reef and lagoon environments, the sediments are moved shoreward to the beach, transport along the shore and sometimes, eventually lost offshore, often as the result of tropical storms. Comprehensive studies of the balance between the supply and loss of carbonate sediments and beach dynamics have been completed for the islands of Mauritius and Barbados. Field studies and remote sensing (Compact Airborne Spectrometry Imaging) have been applied to develop carbonate sediment production rates for a range of reef and lagoon conditions. Using GIS, these production rates have been integrated to determine sediment supply rates for different segments of the coastline. 1-D and 2-D models of waves, hydrodynamics, sediment transport and morphodynamics were set-up and tested against observed beach response to storm events or a sequence of storm events. These complex deterministic models are not suitable for application over periods of decades. However, it was possible to characterize storm events by the extent of sand loss, and relate this to key descriptive factors for groups of storm events, thereby encapsulating the erosion response. A long-term predictive tool for evaluating beach erosion and accretion response, over a period of several decades, was developed by combining the supply rates for carbonate sediment and the encapsulated representation of the loss rates through physical processes. The ability of this predictive tool was successfully tested against observed long term beach evolution along sections of the coast in Barbados and Mauritius using air photo analysis in GIS for shoreline change over periods of 40 years. The long-term predictive tool for carbonate beach evolution provided valuable support to developing coastal zone management policy and actions to preserve the beaches in their natural form, minimizing the need for artificial nourishment of the beaches. Many models of sediment movement on shorelines are derived from clastic examples, and fit carbonate coastlines only with difficulty. We have combined field surveys of benthic biota, estimates of sediment production from skeletal growth and bioerosion, and sediment destruction by comminution and dissolution with dynamic models of sediment movement in the littoral zone, achieving improved understanding of coastal processes of erosion and deposition. Mauritius is fringed by shallow lagoons, often with luxuriant stands of Acropora. The offshore region is exhumed Pleistocene-all the sediment on the beaches comes from the lagoons. From surveys of coral cover, and estimates of sediment production from reef, sand and hardground areas, we produced dynamic models that faithfully hindcast shoreline dynamics for decades, and allowed identification of regions especially vulnerable to erosion. On the south coast of Barbados, one of the main issues in stabilising and rehabilitation the coastline is the balance between sediment from longshore drift and local sources. By identifying localised areas of characteristic sediment-producers (e.g., the foraminiferan Homotrema rubrum, the green alga Halimeda), we were able to determine the balance between proximal and distal sediment sources. The resulting model hindcasts the coastline through all the major hurricanes of the past 30 years.

  1. GEM: Statistical weather forecasting procedure

    NASA Technical Reports Server (NTRS)

    Miller, R. G.

    1983-01-01

    The objective of the Generalized Exponential Markov (GEM) Program was to develop a weather forecast guidance system that would: predict between 0 to 6 hours all elements in the airways observations; respond instantly to the latest observed conditions of the surface weather; process these observations at local sites on minicomputing equipment; exceed the accuracy of current persistence predictions at the shortest prediction of one hour and beyond; exceed the accuracy of current forecast model output statistics inside eight hours; and be capable of making predictions at one location for all locations where weather information is available.

  2. Physical processes that control droplet transport in rock fracture systems

    NASA Astrophysics Data System (ADS)

    Hay, Katrina Moran

    Aquifer recharge is generally driven by fluids that move from the Earths surface to groundwater through the unsaturated zone, also known as the vadose zone. When the vadose zone is fractured, fluids, which may include contaminants, can move through the fracture network as well as the porous matrix. Such a network of fractures can provide a more rapid path, thereby reducing contact time between the fluid and the matrix. Contact time allows for exchange of solutes between the fluid and the porous matrix, thus being able to quantify contact time is important. In addition, the behavior of fluids within a fracture network has been found to be very complex; large-scale models are yet not able to predict transport paths or flux rates. Because, small-scale flow phenomena can strongly influence the large-scale behavior of fluid movement through systems of fractures, it is important that small-scale dynamics be properly understood in order to improve our predictive capabilities in these complex systems. Relevant flow dynamics includes the impact of boundary conditions, fluid modes that evolve in time and space and transitions between modes. This thesis presents three investigations aimed at understanding the physical processes governing fluid movement in unsaturated fractures, with the ultimate goal of improving predictive relationships for fluid transport in rock fracture systems. These investigations include a theoretical analysis of the wetting of a rough surface, an experimental study of the dynamics of fluid droplets (or liquid bridges) moving in a single fracture and a theoretical analysis of the movement of a fluid droplet encountering a fracture intersection. Each investigation is motivated by environmental applications. Development of an analytical equation for the wetting of a rough surface is based on a balance between capillary forces and frictional resistive forces. The resulting equation predicts movement of the liquid invasion front driven solely by the surface roughness; the relationship was found to exhibit a square root of time dependence. Rough surfaces also affect the movement of bulk fluid through the fractures. The speed of droplets moving downward between smooth and rough surfaces is seen to be significantly different. Experiments were used to develop predictive algorithms to calculate the speed of droplets in unsaturated rock fractures, which incorporate an adjusted contact angle for wet rough surfaces, and also incorporate the effect of dynamics on the evolution of the advancing contact angle. The third paper investigates the effect of intersection geometry on the larger scale distribution of fluid in a system of fractures. Fluid movement through fracture intersections depends on input flow parameters, geometry of the system, and capillary and gravitational forces. The physical mechanisms governing the process are analyzed to predict distribution of liquid into fracture branches and velocity of the output flow. This study will improve the ability to incorporate pore-scale fluid physics phenomena into large-scale models for predicting flow transport in rock fracture systems.

  3. Convection in the Physical Vapor Transport Process. Part 2; Thermosolutal

    NASA Technical Reports Server (NTRS)

    Duval, Walter M. B.

    1994-01-01

    We consider the effect of an inert gas on the diffusive-convective physical vapor transport process. We investigate the case when the temperature gradient is stabilizing and the concentration gradient is destabilizing for a wide parametric range. When an inert gas is present, the thermal and solutal convection oppose each other. The solutal field is destabilizing while the thermal field and the advective-diffusive flux stabilize the flow field. When the pressure of the inert component is increased, the stabilizing effect of the advective-diffusive flux is decreased. The intensity of convection as well as the oscillatory transient time increases. Below, the critical Rayleigh number, the nonlinear dynamics of the flow field show an oscillatory approach to steady state. For parametric values in the neighborhood of the critical Rayleigh number, the flow field undergoes a chaotic transient which settles to a periodic state. The asymptotic state of the flow field shows that growth and amalgamation of cells yields an overturning motion which results in an asymmetric cellular structure. The low gravity environment yields the stabilizing advective-diffusive flow which results in uniform temperature and concentration gradients near the crystal interface.

  4. Linking Weathering, Rock Moisture Dynamics, Geochemistry, Runoff, Vegetation and Atmospheric Processes through the Critical Zone: Graduate Student led Research at the Eel River Critical Zone Observatory

    NASA Astrophysics Data System (ADS)

    Dietrich, W. E.

    2014-12-01

    In the Eel River Critical Zone Observatory lies Rivendell, a heavily-instrumented steep forested hillslope underlain by nearly vertically dipping argillite interbedded with sandstone. Under this convex hillslope lies "Zb", the transition to fresh bedrock, which varies from less than 6 m below the surface near the channel to 20 m at the divide. Rempe and Dietrich (2014, PNAS) show that the Zb profile can be predicted from the assumption that weathering occurs when drainage is induced in the uplifting fresh bedrock under hillslopes by lateral head gradients driven by channel incision at the hillslope boundary. Infiltrating winter precipitation is impeded at the lower conductivity boundary at Zb, generating perched groundwater that dynamically pulses water laterally to the channel, controlling stream runoff. Below the soil and above the water table lies an unsaturated zone through which all recharge to the perched groundwater (and thus all runoff to channels) occurs. It is this zone and the waters in them that profoundly affect critical zone processes. In our seasonally dry environment, the first rains penetrate past the soil and moisten the underlying weathered bedrock (Salve et al., 2012, WRR). It takes about 200 to 400 mm of cumulative rain, however, before the underlying groundwater rises significantly. Oshun et al (in review) show that by this cumulative rainfall the average of the wide-ranging isotopic signature of rain reaches a nearly constant average annual value. Consequently, the recharging perched groundwater shows only minor temporal isotopic variation. Kim et al, (2014, GCA) find that the winter high-flow groundwater chemistry is controlled by relatively fast-reacting cation exchange processes, likely occurring in transit in the unsaturated zone. Oshun also demonstrates that the Douglas fir rely on this rock moisture as a water source, while the broadleaf trees (oaks and madrone) use mostly soil moisture. Link et al (2014 WRR) show that Doug fir declines in transpiration rate significantly compared to the madrone during summer high water stress periods, with may induce feedbacks from the forest to atmospheric temperature and humidity. Collectively these studies spotlight the seasonally dynamic unsaturated zone in the weathered bedrock beneath the soil as key to understanding critical zone processes.

  5. NASA's Advancements in Space-Based Spectrometry Lead to Improvements in Weather Prediction and Understanding of Climate Processes

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Iredell, Lena

    2010-01-01

    AIRS (Atmospheric Infra-Red Sounder), was launched, in conjunction with AMSU-A (Advanced Microwave Sounding Unit-A) on the NASA polar orbiting research satellite EOS (Earth Observing System) Aqua satellite in May 2002 as a next generation atmospheric sounding system. Atmospheric sounders provide information primarily about the vertical distribution of atmospheric temperature and water vapor distribution. This is achieved by measuring outgoing radiation in discrete channels (spectral intervals) which are sensitive primarily to variations of these geophysical parameters. The primary objectives of AIRS/AMSU were to utilize such information in order to improve the skill of numerical weather prediction as well as to measure climate variability and trends. AIRS is a multi-detector array grating spectrometer with 2378 channels covering the spectral range 650/cm (15 microns) to 2660/cm (3.6 microns) with a resolving power (i/a i) of roughly 1200 where a i is the spectral channel bandpass. Atmospheric temperature profile can be determined from channel observations taken within the 15 micron (the long-wave CO2 absorption band) and within the 4.2 micron (the short-wave CO2 absorption band). Radiances in these (and all other) spectral intervals in the infrared are also sensitive to the presence of clouds in the instrument?s field of view (FOV), which are present about 95% of the time. AIRS was designed so as to allow for the ability to produce accurate Quality Controlled atmospheric soundings under most cloud conditions. This was achieved by having 1) extremely low channel noise values in the shortwave portion of the spectrum and 2) a very flat spatial response function within a channel?s FOV. IASI, the high spectral resolution IR interferometer flying on the European METOP satellite, does not contain either of these important characteristics. The AIRS instrument was also designed to be extremely stabile with regard to its spectral radiometric characteristics, which is critical with regard to the ability to measure accurate long term trends.

  6. Weather information network including graphical display

    NASA Technical Reports Server (NTRS)

    Leger, Daniel R. (Inventor); Burdon, David (Inventor); Son, Robert S. (Inventor); Martin, Kevin D. (Inventor); Harrison, John (Inventor); Hughes, Keith R. (Inventor)

    2006-01-01

    An apparatus for providing weather information onboard an aircraft includes a processor unit and a graphical user interface. The processor unit processes weather information after it is received onboard the aircraft from a ground-based source, and the graphical user interface provides a graphical presentation of the weather information to a user onboard the aircraft. Preferably, the graphical user interface includes one or more user-selectable options for graphically displaying at least one of convection information, turbulence information, icing information, weather satellite information, SIGMET information, significant weather prognosis information, and winds aloft information.

  7. Physical Abuse, Cognitive and Emotional Processes, and Aggressive/Disruptive Behavior Problems

    ERIC Educational Resources Information Center

    Teisl, Michael; Cicchetti, Dante

    2008-01-01

    Cognitive and emotional processes were examined in maltreated children with a history of physical abuse (n = 76), children with a history of maltreatment other than physical abuse (i.e., sexual abuse, physical neglect, and emotional maltreatment; n = 91), and a group of non-maltreated comparison children (N = 100). Physical abuse was associated

  8. The Process of Physics Teaching Assistants' Pedagogical Content Knowledge Development

    ERIC Educational Resources Information Center

    Seung, Eulsun

    2013-01-01

    This study explored the process of physics teaching assistants' (TAs) PCK development in the context of teaching a new undergraduate introductory physics course. "Matter and Interactions" (M&I) has recently adopted a new introductory physics course that focuses on the application of a small number of fundamental physical

  9. Deciphering the weathering processes using environmental mineralogy and geochemistry: Towards an integrated model of laterite and podzol genesis in the Upper Amazon Basin

    NASA Astrophysics Data System (ADS)

    Fritsch, Emmanuel; Balan, Etienne; Régina Do Nascimento, Nadia; Allard, Thierry; Bardy, Marion; Bueno, Guilherme; Derenne, Sylvie; Melfi, Adolpho José; Calas, Georges

    2011-02-01

    This article reports major results from collaborative research between France and Brazil on soil and water systems, carried out in the Upper Amazon Basin. It reveals the weathering processes acting in the partly inundated, low elevation plateaus of the Basin, mostly covered by evergreen forest. Our findings are based on geochemical data and mineral spectroscopy that probe the crystal chemistry of Fe and Al in mineral phases (mainly kaolinite, Al- and Fe-(hydr)oxides) of tropical soils (laterites). These techniques reveal crystal alterations in mineral populations of different ages and changes of metal speciation associated with mineral or organic phases. These results provide an integrated model of soil formation and changes (from laterites to podzols) in distinct hydrological compartments of the Amazon landscapes and under altered water regimes.

  10. Snowslip Mountain Weather Station, MT

    USGS Multimedia Gallery

    USGS Physical Scientist Erich Peitzsch sets up a weather station on Snowslip Mountain in Glacier National Park.  It provides meteorological data for avalanche forecasting and research, including wind speed and direction, air temperature, relative humidity, and net radiation measurements....

  11. Solar variability, weather, and climate

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Advances in the understanding of possible effects of solar variations on weather and climate are most likely to emerge by addressing the subject in terms of fundamental physical principles of atmospheric sciences and solar-terrestrial physis. The limits of variability of solar inputs to the atmosphere and the depth in the atmosphere to which these variations have significant effects are determined.

  12. Reconnaissance of Field Sites for the Study of Chemical Weathering on the Guayana Shield, South America

    SciTech Connect

    Steefell, C I

    2003-02-01

    Despite the fact that chemical weathering of silicate rocks plays an important role in the draw-down of CO{sub 2} over geologic time scales (Berner and Berner, 1996), the overall controls on the rate of chemical weathering are still not completely understood. Lacking a mechanistic understanding of these controls, it remains difficult to evaluate a hypothesis such as that presented by Raymo and Ruddiman (1992), who suggested that enhanced weathering and CO{sub 2} draw-down resulting from the uplift of the Himalayas contributed to global cooling during the Cenozoic. At an even more fundamental level, the three to four order of magnitude discrepancy between laboratory and field weathering rates is still unresolved (White et al., 1996). There is as yet no comprehensive, mechanistic model for silicate chemical weathering that considers the coupled effects of precipitation, vadose zone flow, and chemical reactions. The absence of robust process models for silicate weathering and the failure to resolve some of these important questions may in fact be related-the controls on the overall rates of weathering cannot be understood without considering the weathering environment as one in which multiple, time-dependent chemical and physical processes are coupled (Malmstrom, 2000). Once chemical weathering is understood at a mechanistic process level, the important controls on chemical weathering (physical erosion, temperature, precipitation) can be folded into larger scale models tracking the global carbon cycle. Our goal in this study was to carry out the preliminary work needed to establish a field research site for chemical weathering om the Cuayana Shield in South America. The Guayana Shield is a Precambrian province greater than 1.5 billion years old covering portions of Venezuela, Guyana (the country), Surinam, French Guiana, and Brazil (Figure 1). More important than the age of the rocks themselves, however, is the age of the erosion surface developed on the Shield, with estimates ranging as old as 65 million years. Preserved mostly in highlands, this very old erosion surface represents an end-member site where physical erosion has been significantly slower than the rate of chemical weathering. Much of the Shield is also noteworthy for the fact that chemical weathering is still occurring today, thus offering the chance to study a system in which a present day weathering regime is accompanied by an integrated weathering record over millions of years (Soler and Lasaga, 2000). If rates of chemical weathering can be determined for this very old weathering system where physical erosion is minor, they can then be compared with rates determined from sites with similar annual temperatures and rainfall, but much higher physical erosion rates. Comparative studies of this kind can provide a parameterization of chemical weathering rates as a function of physical erosion and tectonic uplift that can be used in global models for the carbon cycle.

  13. Space Weathering on Airless Bodies

    NASA Astrophysics Data System (ADS)

    Pieters, C. M.; Blewett, D. T.; Hiroi, T.; Marchi, S.; McFadden, L. A.; Noble, S. K.; De Sanctis, M. C.; Taylor, L. A.; Reddy, V.

    2012-12-01

    Space weathering refers to an array of processes that measurably alter the character of surfaces that are exposed to the space environment with time. Important observations and constraints come from integration of ground truth sample information and remotely sensed data for the surface. Currently, such combined sample and remote data are available for the Moon, a few near-Earth asteroids (NEAs), and Vesta. Although common processes exist on every planetary body visited, the character of surface alteration by space weathering on airless bodies is very dependent on the particular space environment and the geology and composition of the host. For the Moon, lunar samples have provided a direct link between exposure to the space environment and the development and accumulation of nanophase reduced iron (npFe^0) on soil grains [1]. The optical properties of npFe^0 are well defined experimentally [2]. The resulting effects on lunar materials include reduction of diagnostic absorption bands, prominence of a red-sloped near-infrared (NIR) continuum, and lower albedo [3]. For Eros and Hyabusa, two NEAs visited by spacecraft, similar, but less pronounced optical effects are observed [4]. The in situ Eros measurements and returned Hyabusa samples confirm both bodies are ordinary chondritic in composition despite the optical alteration of their surface [5]. The main-belt proto-planet Vesta has long been associated with HED basaltic achondrite meteorites [6]. Data from Dawn reveal an anti-correlation between mineral band strength and albedo often observed around fresh craters. However, no association is seen with NIR continuum slope implying little development of significant npFe^0 [7]. Several physical and compositional reasons that hinder npFe^0 creation on Vesta are now recognized; alteration processes are instead more linked with dispersal of opaques and regolith mixing processes [7, 8]. Space weathering and evolution of the optical properties of regolith on airless bodies include the following general principles: A. Accumulation of nanophase opaque coatings on regolith grains with time is a common process and involves solar wind bombardment and/or micrometeoroid vaporization. This may be more dominant in the inner solar system. B. Although recent impacts often produce local heterogeneity at a crater, repeated impact mixing by smaller events results in apparent surficial homogenization over time. There is a suggestion that regolith mixing may be dominant for low-gravity regimes. Common related products involve impact darkening that creates and disperses micron-scale opaques [9] that darken but do not 'redden' the surface. C. Surface gravity and electrostatic forces strongly affect the development and retention of space weathering products. These are currently poorly quantified but steady-state processes appear to provide regional uniformity. References: 1. Keller & McKay, GCA, 1997; Taylor et al., JGR, 2001; 2010; Noble et al., MaPS, 2001. 2. Sasaki et al., Nature, 2001; Noble et al., Icarus, 2007. 3 Pieters et al., MaPS, 2000; Hapke JGR, 2001. 4. Clark et al., MaPS, 2001; Binzel et al., MaPS, 2001; Hiroi et al., Nature, 2006. 5. Trombke et al., Science, 2000; Nakamura et al., Science, 2011. 6. McCord et al., Science, 1970; De Sanctis et al., Science, 2012. 7. Pieters et al., Nature in press, 2012. 8. McCord et al., Nature in press; Reddy et al., Icarus, submitted. 9. Britt & Pieters, GCA, 1994.

  14. Mercury's Weather-Beaten Surface: An Examination of the Relevant Processes Through Comparisons and Contrasts with the Moon and Asteroids

    NASA Astrophysics Data System (ADS)

    Domingue, D. L.; Schirver, D.; Trvn?ek, P. M.; Helbert, J.

    2015-11-01

    We examine global color properties of Mercury and their correlations to the predicted trends due to particle bombardment and thermal processing. Color ratio and spectral slope analyzes are interpreted relative to lunar and asteroid studies.

  15. Teaching Weather Concepts.

    ERIC Educational Resources Information Center

    Sebastian, Glenn R.

    Ten exercises based on the weather map provided in the national newspaper "U.S.A. Today" are used to teach intermediate grade students about weather. An overview describes the history of "U.S.A. Today," the format of the newspaper's weather map, and the map's suitability for teaching weather concepts. Specific exercises, which are briefly

  16. Weather in Your Life.

    ERIC Educational Resources Information Center

    Kannegieter, Sandy; Wirkler, Linda

    Facts and activities related to weather and meteorology are presented in this unit. Separate sections cover the following topics: (1) the water cycle; (2) clouds; (3) the Beaufort Scale for rating the speed and force of wind; (4) the barometer; (5) weather prediction; (6) fall weather in Iowa (sleet, frost, and fog); (7) winter weather in Iowa

  17. Weather in Your Life.

    ERIC Educational Resources Information Center

    Kannegieter, Sandy; Wirkler, Linda

    Facts and activities related to weather and meteorology are presented in this unit. Separate sections cover the following topics: (1) the water cycle; (2) clouds; (3) the Beaufort Scale for rating the speed and force of wind; (4) the barometer; (5) weather prediction; (6) fall weather in Iowa (sleet, frost, and fog); (7) winter weather in Iowa…

  18. Weather satellite activity mixed

    NASA Astrophysics Data System (ADS)

    On August 21 at 7:15 P.M. EDT, controllers lost contact with the NOAA-13 weather satellite due to a power system failure aboard the craft. Almost simultaneously, however, representatives of U.S. and European agencies signed an agreement promising mutual cooperation and backup of one another's geostationary weather satellites, effective when both agencies have systems in place, expected in 1995.The newest in a series of polar-orbiting weather satellites, NOAA-13 was launched on August 9 from Vandenburg Air Force Base, Calif., to monitor the Earth's ocean and atmosphere, collecting data for direct transmission to users around the world and to central data-processing centers. According to officials at NASA and the National Oceanographic and Atmospheric Administration, the spacecraft showed steadily decreasing battery voltages and currents during ground passes after 3:45 EDT on August 21, although output from the solar panels remained normal. Charles E. Thienel, NASA Goddard Space Flight Center, Greenbelt, Md., stated that these circumstances indicate a failure in the circuitry between the solar arrays and the batteries.

  19. Experimental Approaches to Space Weathering

    NASA Astrophysics Data System (ADS)

    Allen, C. C.; Morris, R. V.; McKay, D. S.

    1996-03-01

    The process of space weathering in lunar soil (maturation) includes the combined effects of micrometeorite impacts and solar wind interactions. Impacts melt small volumes of soil containing solar wind hydrogen and carbon. The melt quenches rapidly to agglutinitic glass in a strongly reducing environment. Glass formation under these conditions causes reduction of Fe2+ in the glass to nanophase (~4-33 nm) iron metal (np-Fe0). Space weathering also produces distinct changes in the reflectance spectra of lunar soils. With increasing maturity overall soil albedo is reduced, spectral contrast is diminished, and the continuum slope is increased. We are attempting to duplicate the effects of space weathering in the laboratory using hydrogen reduction at subsolidus temperatures. Alterations induced in the mineralogical and optical properties of 17 lunar soils resemble changes caused by natural space weathering.

  20. Process reconstruction: From unphysical to physical maps via maximum likelihood

    SciTech Connect

    Ziman, Mario; Plesch, Martin; Stelmachovic, Peter; Buzek, Vladimir

    2005-08-15

    We show that the method of maximum likelihood (MML) provides us with an efficient scheme for the reconstruction of quantum channels from incomplete measurement data. By construction this scheme always results in estimations of channels that are completely positive. Using this property we use the MML for a derivation of physical approximations of unphysical operations. In particular, we analyze the optimal approximation of the universal NOT gate as well as the physical approximation of a quantum nonlinear polarization rotation.

  1. Weather Derivative Valuation

    NASA Astrophysics Data System (ADS)

    Jewson, Stephen; Brix, Anders

    2005-04-01

    Weather Derivative Valuation is the first book to cover all the meteorological, statistical, financial and mathematical issues that arise in the pricing and risk management of weather derivatives. There are chapters on meteorological data and data cleaning, the modelling and pricing of single weather derivatives, the modelling and valuation of portfolios, the use of weather and seasonal forecasts in the pricing of weather derivatives, arbitrage pricing for weather derivatives, risk management, and the modelling of temperature, wind and precipitation. Specific issues covered in detail include the analysis of uncertainty in weather derivative pricing, time-series modelling of daily temperatures, the creation and use of probabilistic meteorological forecasts and the derivation of the weather derivative version of the Black-Scholes equation of mathematical finance. Written by consultants who work within the weather derivative industry, this book is packed with practical information and theoretical insight into the world of weather derivative pricing.

  2. The problems of solar-terrestrial coupling and new processes introduced to the physics of the ionosphere from the physics of atomic collisions

    NASA Astrophysics Data System (ADS)

    Avakyan, Sergei

    2010-05-01

    Further progress in research of solar-terrestrial coupling requires better understanding of solar variability influence on the ionosphere. The most powerful manifestations of solar variability are solar flares and geomagnetic storms. During a flare EUV/X-ray irradiations are completely absorbed in the ionosphere producing SID. During geomagnetic storms precipitations of electrons with energy of several keV (and to a lesser extent protons precipitations) from radiation belts and geomagnetosphere produce additional ionization and low latitude auroras. Considering the physics of ionosphere during the last several decades we have been taking into account three novel processes well known in the physics of atomic collisions. These are Auger effect [S. V. Avakyan, The consideration of Auger processes in the upper atmosphere of Earth. In Abstracts of paper presented at the Tenth scien. and techn. Conf. of young specialists of S.I. Vavilov State Optical Institute, 1974, 29-31.], multiple photoionization of upper, valence shell [S.V. Avakyan, The source of O++ ions in the upper atmosphere, 1979, Cosmic Res, 17, 942 - 943] and Rydberg excitation of all the components of upper atmosphere [S.V. Avakyan, The new factor in the physics of solar - terrestrial relations - Rydberg atomic and molecules states. Conf. on Physics of solar-terrestrial relationships, 1994, Almaty, 3 - 5]. In the present paper the results of bringing these new processes in the ionospheric physics are discussed and also its possible role in the physics of solar-terrestrial coupling is considered. Involving these processes to the model estimations allowed us for the first time to come to the following important conclusions: - Auger electrons play the determinant role at the formation of energy spectrum of photoelectrons and secondary auroral electrons at the range above 150 eV; - double photoionization of the outer shell of the oxygen atom (by a single photon) plays a dominant role in the formation of ionospheric doubly charged positive ions, and Auger effect mainly determines the formation of double- and triple charged ions in the low ionosphere of planets and also comets; - transitions in the Rydberg excited ionospheric atoms and molecules play the main role in generation of new type of upper atmospheric emission - microwave characteristic radiation. The ionospheric O++ ions fill the magnetosphere after geomagnetic storms. These ions scatter the solar radiation in one of the most intense lines with a wavelength of 30.4 nm (He+) and also in the 50.7-, 70.3-, 83.3-83.5-nm lines in geocorona to the nocturnal side, giving rise to additional ionization and optical excitation in the F-region. The first calculations of the excitation rate of Rydberg states by photoelectrons and by auroral electrons (including Auger electrons) were carried out. It was shown that such process can generate the microwave ionospheric radioemission. Such emissions were observed during solar flares and in auroras. We suggest that Rydberg microwave radioemissions which take place during ionospheric disturbances produced by the solar flares and geomagnetic storms can be considered as an agent of influence of solar-geomagnetic activity on the biosphere and also as a factor of Sun-weather-climate links All these results obtained experimental confirmation in space investigations and in some ground-based measurements carried out with radiophysical and optical methods. The new processes which we introduced to the physics of upper atmosphere and ionosphere are now widely used in the ionospheric science for interpretation of spacecraft measurement data (the spacecrafts ISIS, GEOS-1, IMAGE, the satellites DE-1,-B, EXOS-D (AKEBOHO), FAST, Intercosmos-19, -24, -25, the orbital stations "Salut", "Mir"). There is a Russian patent on the method of remote registration of radioactive atmospheric clouds and nuclear weapon tests over the atmosphere by means of optical fluorescence which is based on Auger processes.

  3. Deeply weathered basement rocks in Norway

    NASA Astrophysics Data System (ADS)

    Bnner, Marco; Knies, Jochen; Fredin, Ola; Olesen, Odleiv; Viola, Giulio

    2014-05-01

    Recent studies show that, in addition to tectonic processes, surface processes have also had a profound impact on the topography of Norway. This is especially obvious for the northernmost part of the Nordland county and for western Norway, where the current immature Alpine-type topography cannot be easily explained by tectonic processes only. Erosion of the sedimentary succession also does not seem sufficient to explain the observed relief. Common remnants of deeply weathered basement rocks, however, indicate a history of deep alteration and later erosion of the bedrock, which needs to be considered as another important factor in the development of the topographic relief. Most of the sites with deeply weathered basement exhibit a clay-poor grussy type of weathering, which is generally considered to be of relatively young age (Plio-/Pleistocene) and thought to represent an intermediate stage of weathering. Unfortunately, small amounts or complete absence of clay minerals in these weathering products precluded the accurate dating of this weathered material. Scandinavia was exposed to a large range of glaciations and the once extensive sedimentary successions have been almost entirely eroded, which impedes a minimum age estimate of the weathering profile. Although several sites preserving remnants of deep weathering can still be observed onshore Norway, they are all covered by Quaternary overburden and the age of the regolith remains thus unconstrained and a matter of debate. The only exception is a small Mesozoic basin on Andya, northern Norway, where weathered and clay-poor saprolite was found underlying Jurassic and Cretaceous sedimentary rocks. Over the last few years the Geological Survey of Norway (NGU) has mapped and investigated deep weathering onshore Norway to better understand weathering processes and to constrain the age of the weathering remnants. The combined interpretation of geophysical, mineralogical and geochemical data, together with recent observations from the Norwegian shelf, where grussy type of weathered bedrock was found buried under Mesozoic sediments, leads to the conclusion that coarse-grained, clay-poor saprolite does not necessarily indicate a young age of weathering but could in fact be of Early Mesozoic age or even older. The Late Jurassic to Early Cretaceous faults in the Lofoten-Vesterlen area are for instance little affected by weathering processes. With the goal to refine our understanding of the complex weathering processes and to constrain them in time, the NGU is establishing a new K-Ar laboratory for the dating and characterization of illite grown authigenically in the saprolites. It is expected that the data generated therein will contribute new quantitative constraints to the long-lasting debate as to the age of weathering processes in Scandinavia.

  4. Weather Modification—a Scenario for the Future.

    NASA Astrophysics Data System (ADS)

    List, Roland

    2004-01-01

    The ever-increasing severe economic damage imposed on national and world wide economies by severe weather, the need for sufficient and safe water resources for an increasing world population, and the threat of adverse climate change led to this critical assessment of the state-of-the-art of weather modification (WM) and to a proposal of a road map for the future.Special attention is given to rain enhancement because it is further developed than snowpack augmentation, hail suppression, tornado and hurricane modification, and other weather-related disaster control ideas. The question of what makes a rain enhancement experiment acceptable to the scientific community is answered by the World Meteorological Organization's (WMO) criteria, which address statistical evaluation, the measurement of rain, the understanding of nature's precipitation processes with the underlying physics and dynamics of clouds and cloud systems, and the transferability of experiment design. These criteria are no longer specific enough or satisfactory and will have to be reconsidered.An actual WM experiment also involves a variety of techniques and technologies, aspects that need to be complemented by numerical modeling of clouds and cloud responses to seeding. Modeling also allows assessment of the extra-area effects, that is, detrimental effects of precipitation on adjacent areas. Assimilation models may be giving better estimates of the rain at the ground because they can integrate restricted information from radar and rain gauges with mesoscale meteorological and remote sensing, as well as hydrological, data. However, massive improvements in computer capacity are required to handle these problems.Weather modification has been progressing very slowly in the past because of the enormity of the problem and the fact that the precipitation process is far from being understood. Considering that rain increases are attempted within a range of 10% 20%, the lack of knowledge at corresponding accuracy is particularly evident in the fields of cloud physics, cloud and cloud systems dynamics, weather forecasting, numerical modeling, and measuring technology.Benefits of new intensive studies of precipitation processes will not be limited to WM; they are also vital to improving weather forecasting and climate change modeling. There is one additional aspect of WM; WM can also be used to test newly developed precipitation physics and models by studying if the clouds react to seeding in the predicted manner.This article is a wake-up call to put more intellectual and financial resources into the exploration and modification of the precipitation processes in all their forms. All these points lead to the suggestion of an outline of a national precipitation research and weather modification program.

  5. Physical processes of quartz amorphization due to friction

    NASA Astrophysics Data System (ADS)

    Nakamura, Y.; Muto, J.; Nagahama, H.; Miura, T.; Arakawa, I.; Shimizu, I.

    2011-12-01

    Solid state amorphization of minerals occurs in indentations, in shock experiments, and in high pressure metamorphic quartz rock. A production of amorphous material is also reported in experimentally created silicate gouges (Yund et al., 1990), and in San Andreas Fault core samples (Janssen et al., 2010). Rotary-shear friction experiments of quartz rocks imply dynamic weakening at seismic rates (Di Toro et al., 2004). These experiments have suggested that weakening is caused by formation and thixotropic behavior of a silica gel layer which comprises of very fine particles of hydrated amorphous silica on fault gouges (Goldsby & Tullis, 2002; Hayashi & Tsutsumi, 2010). Therefore, physical processes of amorphization are important to better understand weakening of quartz bearing rocks. In this study, we conducted a pin-on-disk friction experiment to investigate details of quartz amorphization (Muto et al, 2007). Disks were made of single crystals of synthetic and Brazilian quartz. The normal load F and sliding velocity V were ranged from 0.01 N to 1 N and from 0.01 m/s to 2.6 m/s, respectively. The friction was conducted using quartz and diamond pins (curvature radii of 0.2 ~ 3 mm) to large displacements (> 1000 m) under controlled atmosphere. We analyzed experiment samples by Raman spectroscopy and FT-IR. Raman spectroscopy (excitation wavelength 532.1 nm) provides lattice vibration modes, and was used to investigate the degree of amorphization of samples. Raman spectra of friction tracks on the disk show clear bands at wavenumbers of 126, 204, 356, 394, and 464 cm-1, characteristic of intact α-quartz. Remarkably, in experiments using diamond pins (F = 0.8 N, normal stress σr calculated by contact area = 293 ~ 440 MPa, V = 0.12 ~ 0.23 m/s), the bands at 204 and 464 cm-1 gradually broaden to reveal shoulders on the higher-wavenumber sides of these peaks. Especially, two distinguished peaks at 490 and 515 cm-1 and a weak broad peak at 606 cm-1 appear sporadically on the track after the slip distance of 43 m. The bands at 490 and 606 cm-1 can be assigned to the symmetric stretching of four-membered Si-O ring (D1 band) and planar three-membered Si-O ring (D2 band) in amorphous silica, respectively. The peak at 515 cm-1 corresponds to the strongest coesite A1 mode arising from four-membered Si-O ring structure. On the other hand, the bands at 464 cm-1 broaden to reveal a shoulder adjacent to the main peak in experiments using quartz pins (F = 1 N, σr = 1 MPa, V = 0.01 ~ 2.6 m/s) after a large displacement (>1000m). These results indicate that quartz change intermediate range structure of SiO2 network during friction, and four or three-membered Si-O rings gradually increase in six-membered quartz. The results of FT-IR analyses on friction tracks showed a broad peak at 3000 -3600 cm-1 which indicates the -OH symmetric stretching band of molecular H2O. It shows that hydration of quartz on friction tracks occur due to friction. The results of Raman spectroscopy and FT-IR imply that Si-O-Si bridging of strained rings preferentially react with water to form hydrated amorphous silica layer on friction surfaces, which is likely to occur weakening.

  6. Space Weather Modeling Services at the Community Coordinated Modeling Center

    NASA Technical Reports Server (NTRS)

    Hesse, Michael

    2006-01-01

    The Community Coordinated Modeling Center (CCMC) is a multi-agency partnership, which aims at the creation of next generation space weather models. The goal of the CCMC is to support the research and developmental work necessary to substantially increase the present-day modeling capability for space weather purposes, and to provide models for transition to the Rapid Prototyping Centers at the space weather forecast centers. This goal requires close collaborations with and substantial involvement of the research community. The physical regions to be addressed by CCMC-related activities range from the solar atmosphere to the Earth's upper atmosphere. The CCMC is an integral part of the National Space Weather Program Implementation Plan, of NASA's Living With a Star (LWS) initiative, and of the Department of Defense Space Weather Transition Plan. CCMC includes a facility at NASA Goddard Space Flight Center. CCMC also provides, to the research community, access to state-of-the-art space research models. In this paper we will provide a description of the current CCMC status, discuss current plans, research and development accomplishments and goals, and describe the model testing and validation process undertaken as part of the CCMC mandate. Special emphasis will be on solar and heliospheric models currently residing at CCMC, and on plans for validation and verification.

  7. Space Weather Modeling at the Community Coordinated Modeling Center

    NASA Technical Reports Server (NTRS)

    Hesse M.

    2005-01-01

    The Community Coordinated Modeling Center (CCMC) is a multi-agency partnership, which aims at the creation of next generation space weather models. The goal of the CCMC is to support the research and developmental work necessary to substantially increase the present-day modeling capability for space weather purposes, and to provide models for transition to the rapid prototyping centers at the space weather forecast centers. This goal requires dose collaborations with and substantial involvement of the research community. The physical regions to be addressed by CCMC-related activities range from the solar atmosphere to the Earth's upper atmosphere. The CCMC is an integral part of the National Space Weather Program Implementation Plan, of NASA's Living With a Star (LWS) initiative, and of the Department of Defense Space Weather Transition Plan. CCMC includes a facility at NASA Goddard Space Flight Center, as well as distributed computing facilities provided by the US Air Force. CCMC also provides, to the research community, access to state-of-the-art space research models. In this paper we will provide updates on CCMC status, on current plans, research and development accomplishments and goals, and on the model testing and validation process undertaken as part of the CCMC mandate. Special emphasis will be on solar and heliospheric models currently residing at CCMC, and on plans for validation and verification.

  8. Weather data dissemination to aircraft

    NASA Technical Reports Server (NTRS)

    Mcfarland, Richard H.; Parker, Craig B.

    1990-01-01

    Documentation exists that shows weather to be responsible for approximately 40 percent of all general aviation accidents with fatalities. Weather data products available on the ground are becoming more sophisticated and greater in number. Although many of these data are critical to aircraft safety, they currently must be transmitted verbally to the aircraft. This process is labor intensive and provides a low rate of information transfer. Consequently, the pilot is often forced to make life-critical decisions based on incomplete and outdated information. Automated transmission of weather data from the ground to the aircraft can provide the aircrew with accurate data in near-real time. The current National Airspace System Plan calls for such an uplink capability to be provided by the Mode S Beacon System data link. Although this system has a very advanced data link capability, it will not be capable of providing adequate weather data to all airspace users in its planned configuration. This paper delineates some of the important weather data uplink system requirements, and describes a system which is capable of meeting these requirements. The proposed system utilizes a run-length coding technique for image data compression and a hybrid phase and amplitude modulation technique for the transmission of both voice and weather data on existing aeronautical Very High Frequency (VHF) voice communication channels.

  9. Influence of aerosols on weather conditions

    NASA Astrophysics Data System (ADS)

    Palamarchuk, Iuliia; Stepanenko, Sergiy; Ivanov, Sergiy; Ruban, Igor; Pavlova, Hanna

    2014-05-01

    The accurate numerical weather prediction demands the better understanding and detailed representation of aerosol effects in the atmosphere. The presence of various types of aerosols as well as other chemical components in the atmosphere causes different effects on weather, climate and still keeps many unresolved aspects. Non-linear interactions between weather phenomena, in particular, precipitation and aerosols need to be additionally highlighted. To investigate features of the atmosphere sensitivity to aerosols the high resolution limited area model Harmonie (Hirlam Aladin Regional/Meso-scale Operational NWP In Europe) was used. The Harmonie is extensively developing weather forecast modeling system, in which the convection-permitting physics substantially promotes to the near-realistic representation of the aerosol effects complexity. Numerical experiments with modifications in aerosol concentrations were performed over the Finland domain. The direct effect of aerosols associates with changes in both radiation processes and precipitation formation. The presence of aerosols increases cloud drop concentration and reduces the effective drop size. A high density of nuclei population initializes coalescence growth, accelerates precipitation formation, increases cloud lifetime and lags precipitation. Since aerosols disperse and absorb the radiation they have a direct effect on the albedo, which depends on the aerosol type. The land aerosols increase the albedo mainly in the lower atmospheric layers. Higher up, the effect of land aerosols on the shortwave radiation coming down toward the surface is diminished in comparison with aerosols of the marine origin. The high concentrations of continental aerosols lead to changes in the precipitation rate, while sea aerosols mainly cause the displacement in time of the precipitation event.

  10. Enhanced Weather Radar (EWxR) System

    NASA Technical Reports Server (NTRS)

    Kronfeld, Kevin M. (Technical Monitor)

    2003-01-01

    An airborne weather radar system, the Enhanced Weather Radar (EWxR), with enhanced on-board weather radar data processing was developed and tested. The system features additional weather data that is uplinked from ground-based sources, specialized data processing, and limited automatic radar control to search for hazardous weather. National Weather Service (NWS) ground-based Next Generation Radar (NEXRAD) information is used by the EWxR system to augment the on-board weather radar information. The system will simultaneously display NEXRAD and on-board weather radar information in a split-view format. The on-board weather radar includes an automated or hands-free storm-finding feature that optimizes the radar returns by automatically adjusting the tilt and range settings for the current altitude above the terrain and searches for storm cells near the atmospheric 0-degree isotherm. A rule-based decision aid was developed to automatically characterize cells as hazardous, possibly-hazardous, or non-hazardous based upon attributes of that cell. Cell attributes are determined based on data from the on-board radar and from ground-based radars. A flight path impact prediction algorithm was developed to help pilots to avoid hazardous weather along their flight plan and their mission. During development the system was tested on the NASA B757 aircraft and final tests were conducted on the Rockwell Collins Sabreliner.

  11. The quiet revolution of numerical weather prediction

    NASA Astrophysics Data System (ADS)

    Bauer, Peter; Thorpe, Alan; Brunet, Gilbert

    2015-09-01

    Advances in numerical weather prediction represent a quiet revolution because they have resulted from a steady accumulation of scientific knowledge and technological advances over many years that, with only a few exceptions, have not been associated with the aura of fundamental physics breakthroughs. Nonetheless, the impact of numerical weather prediction is among the greatest of any area of physical science. As a computational problem, global weather prediction is comparable to the simulation of the human brain and of the evolution of the early Universe, and it is performed every day at major operational centres across the world.

  12. The quiet revolution of numerical weather prediction.

    PubMed

    Bauer, Peter; Thorpe, Alan; Brunet, Gilbert

    2015-09-01

    Advances in numerical weather prediction represent a quiet revolution because they have resulted from a steady accumulation of scientific knowledge and technological advances over many years that, with only a few exceptions, have not been associated with the aura of fundamental physics breakthroughs. Nonetheless, the impact of numerical weather prediction is among the greatest of any area of physical science. As a computational problem, global weather prediction is comparable to the simulation of the human brain and of the evolution of the early Universe, and it is performed every day at major operational centres across the world. PMID:26333465

  13. Geomorphology's role in the study of weathering of cultural stone

    NASA Astrophysics Data System (ADS)

    Pope, Gregory A.; Meierding, Thomas C.; Paradise, Thomas R.

    2002-10-01

    Great monumental placesPetra, Giza, Angkor, Stonehenge, Tikal, Macchu Picchu, Rapa Nui, to name a feware links to our cultural past. They evoke a sense of wonderment for their aesthetic fascination if not for their seeming permanence over both cultural and physical landscapes. However, as with natural landforms, human constructs are subject to weathering and erosion. Indeed, many of our cultural resources suffer from serious deterioration, some natural, some enhanced by human impact. Groups from the United Nations to local civic and tourism assemblies are deeply interested in maintaining and preserving such cultural resources, from simple rock art to great temples. Geomorphologists trained in interacting systems, process and response to thresholds, rates of change over time, and spatial variation of weathering processes and effects are able to offer insight into how deterioration occurs and what can be done to ameliorate the impact. Review of recent literature and case studies presented here demonstrate methodological and theoretical advances that have resulted from the study of cultural stone weathering. Because the stone was carved at a known date to a "baseline" or zero-datum level, some of the simplest methods (e.g., assessing surface weathering features or measuring surface recession in the field) provide useful data on weathering rates and processes. Such data are difficult or impossible to obtain in "natural" settings. Cultural stone weathering studies demonstrate the importance of biotic and saline weathering agents and the significance of weathering factors such as exposure (microclimate) and human impact. More sophisticated methods confirm these observations, but also reveal discrepancies between field and laboratory studies. This brings up two important caveats for conservators and geomorphologists. For the conservator, are laboratory and natural setting studies really analogous and useful for assessing stone damage? For the geomorphologist, does cultural stone data have any real relevance to the natural environment? These are questions for future research and debate. In any event, cultural stone weathering studies have been productive for both geomorphologists and conservators. Continued collaboration and communication between the geomorphic, historic preservation, archaeological, and engineering research communities are encouraged.

  14. Pilot weather advisor

    NASA Technical Reports Server (NTRS)

    Kilgore, W. A.; Seth, S.; Crabill, N. L.; Shipley, S. T.; Graffman, I.; Oneill, J.

    1992-01-01

    The results of the work performed by ViGYAN, Inc., to demonstrate the Pilot Weather Advisor cockpit weather data system using a broadcast satellite communication system are presented. The Pilot Weather Advisor demonstrated that the technical problems involved with transmitting significant amount of weather data to an aircraft in-flight or on-the-ground via satellite are solvable with today's technology. The Pilot Weather Advisor appears to be a viable solution for providing accurate and timely weather information for general aviation aircraft.

  15. Dimension of physical systems, information processing, and thermodynamics

    NASA Astrophysics Data System (ADS)

    Brunner, Nicolas; Kaplan, Marc; Leverrier, Anthony; Skrzypczyk, Paul

    2014-12-01

    We ask how quantum theory compares to more general physical theories from the point of view of dimension. To do so, we first give two model-independent definitions of the dimension of physical systems, based on measurements and the capacity of storing information. While both definitions are equivalent in classical and quantum mechanics, they are different in generalized probabilistic theories. We discuss in detail the case of a theory known as boxworld, and show that such a theory features systems with dimension mismatch. This dimension mismatch can be made arbitrarily large using an amplification procedure. Furthermore, we show that the dimension mismatch of boxworld has strong consequences on its power for performing information-theoretic tasks, leading to the collapse of communication complexity and to the violation of information causality. Finally, we discuss the consequences of a dimension mismatch from the perspective of thermodynamics, and ask whether this effect could break Landauer's erasure principle and thus the second law.

  16. Earth Observation Services Weather Imaging

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Microprocessor-based systems for processing satellite data offer mariners real-time images of weather systems, day and night, of large areas or allow them to zoom in on a few square miles. Systems West markets these commercial image processing systems, which have significantly decreased the cost of satellite weather stations. The company was assisted by the EOCAP program, which provides government co-funding to encourage private investment in, and to broaden the use of, NASA-developed technology for analyzing information about Earth and ocean resources.

  17. The lithium, boron and strontium isotopic systematics of groundwaters from an arid aquifer system: Implications for recharge and weathering processes

    NASA Astrophysics Data System (ADS)

    Meredith, Karina; Moriguti, Takuya; Tomascak, Paul; Hollins, Suzanne; Nakamura, Eizo

    2013-07-01

    Saline groundwaters are common to inland Australia, but their hydrochemical evolution and origin remain largely unknown. The saline groundwaters in the alluvial aquifers of the Darling River have previously been found to exhibit broad similarity in traditional hydrochemical and isotopic tracers. By contrast, in this study the trace element isotopes (?7Li, ?11B and 87Sr/86Sr) have illuminated more complex hydrogeochemical processes in the same aquifer system. This paper reports the first ever set of ?7Li values in any groundwater system in Australia. They varied from +5.8 to +16.2 with an average value of +9.7 (n = 19) in the alluvial aquifers of the Darling River catchment. The ?11B values were all higher than seawater and close to some of the highest ?11B values ever reported in the literature for a groundwater system (+44.4 to +53.9; average: +48.8, n = 17). The 87Sr/86Sr ratios ranged from 0.708 to 0.713, with an average value of 0.709 (n = 19). The differing signatures in these trace element isotope values, highlighted by discovery of the deeper older groundwater system with heavier Li isotope values and higher 87Sr/86Sr, is an important finding of this research. Simple mixing models between river water and saline groundwater cannot explain the observed variation in trace element isotopes. Hydrochemical evolution was found to be dependent on proximity to the Darling River and depth. Varying degrees of Li and B isotopic fractionation during water-sediment interaction were interpreted to account for the evolution of the saline groundwaters. The measurement of these trace element isotopes has permitted delineation of groundwater end-members that would have otherwise not been identified; in their absence an inaccurate interpretation of the hydrochemical evolution of these saline groundwaters would have been made. This study highlights the importance of a multi-tracer approach, which includes trace element isotopes, in resolving complex geochemical processes in groundwater in semi-arid to arid zone environments.

  18. Questa Baseline and Pre-mining Ground-Water Quality Investigation, 7. A Pictorial Record of Chemical Weathering, Erosional Processes, and Potential Debris-flow Hazards in Scar Areas Developed on Hydrothermally Altered Rocks

    USGS Publications Warehouse

    Plumlee, Geoffrey S.; Ludington, Steve; Vincent, Kirk R.; Verplanck, Philip L.; Caine, Jonathan S.; Livo, K. Eric

    2009-01-01

    Erosional scar areas developed along the lower Red River basin, New Mexico, reveal a complex natural history of mineralizing processes, rapid chemical weathering, and intense physical erosion during periodic outbursts of destructive, storm-induced runoff events. The scar areas are prominent erosional features with craggy headwalls and steep, denuded slopes. The largest scar areas, including, from east to west, Hottentot Creek, Straight Creek, Hansen Creek, Lower Hansen Creek, Sulfur Gulch, and Goat Hill Gulch, head along high east-west trending ridges that form the northern and southern boundaries of the lower Red River basin. Smaller, topographically lower scar areas are developed on ridge noses in the inner Red River valley. Several of the natural scar areas have been modified substantially as a result of large-scale open-pit and underground mining at the Questa Mine; for example, much of the Sulfur Gulch scar was removed by open pit mining, and several scars are now partially or completely covered by mine waste dumps.

  19. Flight Deck Weather Avoidance Decision Support: Implementation and Evaluation

    NASA Technical Reports Server (NTRS)

    Wu, Shu-Chieh; Luna, Rocio; Johnson, Walter W.

    2013-01-01

    Weather related disruptions account for seventy percent of the delays in the National Airspace System (NAS). A key component in the weather plan of the Next Generation of Air Transportation System (NextGen) is to assimilate observed weather information and probabilistic forecasts into the decision process of flight crews and air traffic controllers. In this research we explore supporting flight crew weather decision making through the development of a flight deck predicted weather display system that utilizes weather predictions generated by ground-based radar. This system integrates and presents this weather information, together with in-flight trajectory modification tools, within a cockpit display of traffic information (CDTI) prototype. that the CDTI features 2D and perspective 3D visualization models of weather. The weather forecast products that we implemented were the Corridor Integrated Weather System (CIWS) and the Convective Weather Avoidance Model (CWAM), both developed by MIT Lincoln Lab. We evaluated the use of CIWS and CWAM for flight deck weather avoidance in two part-task experiments. Experiment 1 compared pilots' en route weather avoidance performance in four weather information conditions that differed in the type and amount of predicted forecast (CIWS current weather only, CIWS current and historical weather, CIWS current and forecast weather, CIWS current and forecast weather and CWAM predictions). Experiment 2 compared the use of perspective 3D and 21/2D presentations of weather for flight deck weather avoidance. Results showed that pilots could take advantage of longer range predicted weather forecasts in performing en route weather avoidance but more research will be needed to determine what combinations of information are optimal and how best to present them.

  20. Chemical weathering in active mountain belts controlled by stochastic bedrock landsliding

    NASA Astrophysics Data System (ADS)

    Emberson, Robert; Hovius, Niels; Galy, Albert; Marc, Odin

    2016-01-01

    A link between chemical weathering and physical erosion exists at the catchment scale over a wide range of erosion rates. However, in mountain environments, where erosion rates are highest, weathering may be kinetically limited and therefore decoupled from erosion. In active mountain belts, erosion is driven by bedrock landsliding at rates that depend strongly on the occurrence of extreme rainfall or seismicity. Although landslides affect only a small proportion of the landscape, bedrock landsliding can promote the collection and slow percolation of surface runoff in highly fragmented rock debris and create favourable conditions for weathering. Here we show from analysis of surface water chemistry in the Southern Alps of New Zealand that weathering in bedrock landslides controls the variability in solute load of these mountain rivers. We find that systematic patterns in surface water chemistry are strongly associated with landslide occurrence at scales from a single hillslope to an entire mountain belt, and that landslides boost weathering rates and river solute loads over decades. We conclude that landslides couple erosion and weathering in fast-eroding uplands and, thus, mountain weathering is a stochastic process that is sensitive to climatic and tectonic controls on mass wasting processes.

  1. Vertical structure and physical processes of the Madden-Julian oscillation: Linking hindcast fidelity to simulated diabatic heating and moistening

    NASA Astrophysics Data System (ADS)

    Klingaman, Nicholas P.; Woolnough, Steven J.; Jiang, Xianan; Waliser, Duane; Xavier, Prince K.; Petch, Jon; Caian, Mihaela; Hannay, Cecile; Kim, Daehyun; Ma, Hsi-Yen; Merryfield, William J.; Miyakawa, Tomoki; Pritchard, Mike; Ridout, James A.; Roehrig, Romain; Shindo, Eiki; Vitart, Frederic; Wang, Hailan; Cavanaugh, Nicholas R.; Mapes, Brian E.; Shelly, Ann; Zhang, Guang J.

    2015-05-01

    Many theories for the Madden-Julian oscillation (MJO) focus on diabatic processes, particularly the evolution of vertical heating and moistening. Poor MJO performance in weather and climate models is often blamed on biases in these processes and their interactions with the large-scale circulation. We introduce one of the three components of a model evaluation project, which aims to connect MJO fidelity in models to their representations of several physical processes, focusing on diabatic heating and moistening. This component consists of 20 day hindcasts, initialized daily during two MJO events in winter 2009-2010. The 13 models exhibit a range of skill: several have accurate forecasts to 20 days lead, while others perform similarly to statistical models (8-11 days). Models that maintain the observed MJO amplitude accurately predict propagation, but not vice versa. We find no link between hindcast fidelity and the precipitation-moisture relationship, in contrast to other recent studies. There is also no relationship between models' performance and the evolution of their diabatic heating profiles with rain rate. A more robust association emerges between models' fidelity and net moistening: the highest-skill models show a clear transition from low-level moistening for light rainfall to midlevel moistening at moderate rainfall and upper level moistening for heavy rainfall. The midlevel moistening, arising from both dynamics and physics, may be most important. Accurately representing many processes may be necessary but not sufficient for capturing the MJO, which suggests that models fail to predict the MJO for a broad range of reasons and limits the possibility of finding a panacea.

  2. Heat Balance of a Sheep in the Sun. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    ERIC Educational Resources Information Center

    Hatheway, W. H.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. Specifically, this module develops a method for calculating the exchange of heat between an…

  3. Animal Thermoregulation and the Operative Environmental (Equivalent) Temperature. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Process.

    ERIC Educational Resources Information Center

    Stevenson, R. D.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. Thermoregulation is defined as the ability of an organism to modify its body temperature. This…

  4. Adaptive, maladaptive, mediational, and bidirectional processes of relational and physical aggression, relational and physical victimization, and peer liking.

    PubMed

    Kawabata, Yoshito; Tseng, Wan-Ling; Crick, Nicki R

    2014-01-01

    A three-wave longitudinal study among ethnically diverse preadolescents (N?=?597 at Time 1, ages 9-11) was conducted to examine adaptive, maladaptive, mediational, and bidirectional processes of relational and physical aggression, victimization, and peer liking indexed by peer acceptance and friendships. A series of nested structural equation models tested the hypothesized links among these peer-domain factors. It was hypothesized that (1) relational aggression trails both adaptive and maladaptive processes, linking to more peer victimization and more peer liking, whereas physical aggression is maladaptive, resulting in more peer victimization and less peer liking; (2) physical and relational victimization is maladaptive, relating to more aggression and less peer liking; (3) peer liking may be the social context that promotes relational aggression (not physical aggression), whereas peer liking may protect against peer victimization, regardless of its type; and (4) peer liking mediates the link between forms of aggression and forms of peer victimization. Results showed that higher levels of peer liking predicted relative increases in relational aggression (not physical aggression), which in turn led to more peer liking. On the other hand, more peer liking was predictive of relative decreases in relational aggression and relational victimization in transition to the next grade (i.e., fifth grade). In addition, relational victimization predicted relative increases in relational aggression and relative decreases in peer liking. Similarly, physical aggression was consistently and concurrently associated more physical victimization and was marginally predictive of relative increases in physical victimization in transition to the next grade. More peer liking predicted relative decreases in physical victimization, which resulted in lower levels of peer liking. The directionality and magnitude of these paths did not differ between boys and girls. PMID:24318459

  5. Winter Weather Emergencies

    MedlinePLUS

    Severe winter weather can lead to health and safety challenges. You may have to cope with Cold related health problems, including ... there are no guarantees of safety during winter weather emergencies, you can take actions to protect yourself. ...

  6. Winter Weather: Hypothermia

    MedlinePLUS

    ... Health Matters What's New Preparation & Planning Disasters & Severe Weather Earthquakes Extreme Heat Floods Hurricanes Landslides Tornadoes Tsunamis ... be successfully resuscitated. More Information: Frostbite Disasters & Severe Weather ... Heat Floods Hurricanes Landslides Tornadoes Tsunamis ...

  7. Winter Weather: Frostbite

    MedlinePLUS

    ... About CDC.gov . Natural Disasters and Severe Weather Earthquakes Being Prepared Emergency Supplies Home Hazards Indoor Safety ... Matters What's New Preparation & Planning Disasters & Severe Weather Earthquakes Extreme Heat Floods Hurricanes Landslides Tornadoes Tsunamis Volcanoes ...

  8. Nuclear Physics Issues of r-Process Nucleosynthesis

    SciTech Connect

    Kratz, K.-L.

    2006-03-13

    Nucleosynthesis theory predicts that about half of the chemical elements above iron are formed in explosive stellar scenarios by the r-process, i.e. a combination of rapid neutron captures, inverse photodisintegrations, and slower {beta}-decays, {beta}-delayed processes, as well as fission and possibly interactions with neutrinos. A correct modelling of this process, therefore, requires the knowledge of nuclear properties very far from stability and a detailed description of the astrophysical environments. With respect to nuclear data, after an initial period of measuring classical 'waiting-point' nuclei with magic neutron numbers, recent investigations have paid special attention to shape transitions and the erosion of classical shell gaps with possible occurrence of new magic numbers. The status of experimental and theoretical nuclear data on masses and {beta}-decay properties will be briefly reviewed, and consequences on the overall r-process matter flow up to the cosmochronometers 232Th and 238U will be discussed.

  9. A Library Manager's Guide to the Physical Processing of Nonprint Materials. The Greenwood Library Management Collection.

    ERIC Educational Resources Information Center

    Driessen, Karen C.; Smyth, Shelia A.

    The librarian is presented with a foundation for decision making as it relates to the physical processing of nonprint materials, and with a demonstration of how these decisions move from theoretical to practical physical processing issues. Such issues include packaging and repackaging; treating accompanying materials; labeling; preparing

  10. Coupled model of physical and biological processes affecting maize pollination

    NASA Astrophysics Data System (ADS)

    Arritt, R.; Westgate, M.; Riese, J.; Falk, M.; Takle, E.

    2003-04-01

    Controversy over the use of genetically modified (GM) crops has led to increased interest in evaluating and controlling the potential for inadvertent outcrossing in open-pollinated crops such as maize. In response to this problem we have developed a Lagrangian model of pollen dispersion as a component of a coupled end-to-end (anther to ear) physical-biological model of maize pollination. The Lagrangian method is adopted because of its generality and flexibility: first, the method readily accommodates flow fields of arbitrary complexity; second, each element of the material being transported can be identified by its source, time of release, or other properties of interest. The latter allows pollen viability to be estimated as a function of such factors as travel time, temperature, and relative humidity, so that the physical effects of airflow and turbulence on pollen dispersion can be considered together with the biological aspects of pollen release and viability. Predicted dispersion of pollen compares well both to observations and to results from a simpler Gaussian plume model. Ability of the Lagrangian model to handle complex air flows is demonstrated by application to pollen dispersion in the vicinity of an agricultural shelter belt. We also show results indicating that pollen viability can be quantified by an "aging function" that accounts for temperature, humidity, and time of exposure.

  11. Flagella, flexibility and flow: Physical processes in microbial ecology

    NASA Astrophysics Data System (ADS)

    Brumley, D. R.; Rusconi, R.; Son, K.; Stocker, R.

    2015-12-01

    How microorganisms interact with their environment and with their conspecifics depends strongly on their mechanical properties, on the hydrodynamic signatures they generate while swimming and on fluid flows in their environment. The rich fluid-structure interaction between flagella - the appendages microorganisms use for propulsion - and the surrounding flow, has broad reaching effects for both eukaryotic and prokaryotic microorganisms. Here, we discuss selected recent advances in our understanding of the physical ecology of microorganisms, which have hinged on the ability to directly interrogate the movement of individual cells and their swimming appendages, in precisely controlled fluid environments, and to image them at appropriately fast timescales. We review how a flagellar buckling instability can unexpectedly serve a fundamental function in the motility of bacteria, we elucidate the role of hydrodynamics and flexibility in the emergent properties of groups of eukaryotic flagella, and we show how fluid flows characteristic of microbial habitats can strongly bias the migration and spatial distribution of bacteria. The topics covered here are illustrative of the potential inherent in the adoption of experimental methods and conceptual frameworks from physics in understanding the lives of microorganisms.

  12. Perceptual and processing differences between physical and dichorhinic odor mixtures.

    PubMed

    Schtze, M; Negoias, S; Olsson, M J; Hummel, T

    2014-01-31

    Perceptual integration of sensory input from our two nostrils has received little attention in comparison to lateralized inputs for vision and hearing. Here, we investigated whether a binary odor mixture of eugenol and l-carvone (smells of cloves and caraway) would be perceived differently if presented as a mixture in one nostril (physical mixture), vs. the same two odorants in separate nostrils (dichorhinic mixture). In parallel, we investigated whether the different types of presentation resulted in differences in olfactory event-related potentials (OERP). Psychophysical ratings showed that the dichorhinic mixtures were perceived as more intense than the physical mixtures. A tendency for shift in perceived quality was also observed. In line with these perceptual changes, the OERP showed a shift in latencies and amplitudes for early (more "sensory") peaks P1 and N1 whereas no significant differences were observed for the later (more "cognitive") peak P2. The results altogether suggest that the peripheral level is a site of interaction between odorants. Both psychophysical ratings and, for the first time, electrophysiological measurements converge on this conclusion. PMID:24240030

  13. Thermal Weathering on Airless Planetary Surfaces

    NASA Astrophysics Data System (ADS)

    Pochat, N. G.; Vance, S.; Collins, G. C.

    2009-12-01

    All airless planetary surfaces in our Solar System appear to be covered by a regolith layer. There are several general processes that could form such a regolith layer, including the rain of impactors on the surface, mass wasting, sublimation degradation, and physical weathering by thermal changes. Several of these processes have been well studied on icy satellites [e.g. Moore et al. 1999]. Weathering of craters and regolith generation on airless bodies are presumed to result from micrometeorite impacts. For instance, one could look at examples of smooth terrain on the moon and try to explain smooth terrain on Callisto by small impacts, but the crater density is well below equilibrium. This led Moore et al. (1999) to state, some other process is dominating its surface layer. The question is: what process could this be? Moore et al. (1999) argue that sublimation and deposition is a dominant weathering process occurring on Callisto, but it may not be the only regolith-generating process. Vance et al. (2007) adapted a thermal expansion anisotropy and mismatch driven fracturing model for a matrix of square grains. Recently we have been looking at the stress at grain boundaries in this model. This stress term is dependent on the grain size and rate of temperature change at the surface of the body. The question we are trying to answer is whether the stress generated at grain boundaries during diurnal heating and cooling is enough to generate and propagate fractures in the surface material. We started by developing a one dimensional finite difference thermal model for the near-surface environment on an airless body, insulated on the bottom boundary and driven by insolation and radiation to space on the surface. We also assumed that density was constant with depth. The program can take the different parameters for each body (e.g. the bolometric albedo and distance from the sun) and calculate the temperature change at any depth over a diurnal cycle at any latitude. Ice is a simple material to consider in models of thermal weathering. We have developed a thermal model for airless planetary surfaces in our Solar System. By linking this thermal model to the grain boundary stress model, we are able to place limits on the smallest grain size that permits thermal weathering, and the depth to which cracking will occur on different icy bodies in our solar system. For instance, we found that cracking can occur on the surfaces of Ganymede and Callisto for grain sizes > 0.5 microns. Thermal weathering may be an important process contributing to regolith generation on airless planetary surfaces. This near-surface process may help to speed up other processes like mass wasting and sublimation degradation. We will present maps of susceptibility to thermal cracking for airless planetary surfaces in our solar system at the meeting and compare to what is known about the regolith. References: Moore et al. (1999) Icarus 140, p. 294-312; Vance et al. (2007) Astrobiology 7, p. 987-1005.

  14. Glacial-Interglacial Climatic Controls on Hillslope Processes and Linkages to Fluvial Systems in the Weathering-Limited Landscape of Eastern Grand Canyon

    NASA Astrophysics Data System (ADS)

    Pederson, J. L.; Anders, M. D.

    2002-12-01

    Recent field studies in eastern Grand Canyon have resulted in one of the best-dated and most detailed non-glacial Quaternary stream and hillslope records that exists. A combination of OSL, cosmogenic-surface-exposure, and U-series dating of the mapped stratigraphy paints a picture of geomorphic changes over the past 350 ky as related to climate forcing. The record highlights the sedimentologic linkages, or lack therof, between: a) hillslope, b) tributary, and c) mainstem Colorado River landscape components through time, and is a valuable field data set for understanding dryland landscape responses to climate change. The example of the late Pleistocene record of the different landscape components is reviewed here as an illustration. In the study area, prominent hillslope colluvial mantles are laterally correlated to tributary fill terraces that aggraded between 50-30 ka (OIS 3). Tributary streams must have undergone significant incision into this fill deposit sometime during OIS 2. This stored sediment has been subsequently remobilized by debris-flow and other processes, and stratigraphic evidence indicates a significant tributary stream deposit dated to 12.5-6.5 ka (last deglaciation) was "fed" by this cannibalization of hillslope deposits. In contrast to this evidence of local slopes and tributary streams being linked sedimentologically through time, there is a chronologic and stratigraphic disconnect between local catchments and the "exotic" mainstem Colorado River. A massive fill deposit along the Colorado River corridor dated to 75-60 ka (correlating well to OIS 4) significantly predates the major episode of local tributary aggradation, which is also evident in stratigraphic relations. Known stratigraphy and paleoclimate records in the headwaters of the Colorado River suggest there should be a mainstem fill correlating to the Pinedale glaciation (OIS 2). There is no field evidence for such a deposit, though we speculate that it may be present beneath the channel of the modern river. Likewise, there is no notable early Holocene deposit of the Colorado River to match that of local tributaries. We interpret these data in the context of related work in drylands to indicate that the greater Colorado River is responding to climate forcing in its distant headwaters, whereas local catchments have a time lags on the order of 104 ky between changes to full-glacial climate and the aggradation that eventually occurs downslope as a function of increased bedrock weathering rates. Another pulse of sedimentation is evident only in tributary streams as hillslope mantles were stripped in response to the hydrologic and vegetation changes during early Holocene warming. Importantly, these complex local catchment responses to climate may be distinct to weathering-limited, dryland landscapes.

  15. Weather Fundamentals: Meteorology. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) looks at how meteorologists gather and interpret current weather data collected from sources

  16. Aviation weather services

    NASA Technical Reports Server (NTRS)

    Sprinkle, C. H.

    1983-01-01

    The primary responsibilities of the National Weather Service (NWS) are to: provide warnings of severe weather and flooding for the protection of life and property; provide public forecasts for land and adjacent ocean areas for planning and operation; and provide weather support for: production of food and fiber; management of water resources; production, distribution and use of energy; and efficient and safe air operations.

  17. Weather Fundamentals: Meteorology. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) looks at how meteorologists gather and interpret current weather data collected from sources…

  18. American Weather Stories.

    ERIC Educational Resources Information Center

    Hughes, Patrick

    Weather has shaped United States' culture, national character and folklore; at times it has changed the course of history. The seven accounts compiled in this publication highlight some of the nation's weather experiences from the hurricanes that threatened Christopher Columbus to the peculiar run of bad weather that has plagued American…

  19. Dynamics and materials physics of fault rupture and glacial processes

    NASA Astrophysics Data System (ADS)

    Platt, John Daniel

    This thesis focuses on two main topics, the physics governing how faults rapidly weaken during an earthquake and the thermal and mechanical structure of ice stream shear margins. The common theme linking these two projects is the desire to understand how the complicated interactions between stress and temperature control deformation and failure. All of the problems in this thesis are attacked using a combination of analytic and numerical methods, and the interplay between these two approaches provides a powerful way to understand the different physical balances that dominate in different regimes. We also use aspects of materials science to understand how the often complicated rheologies are controlled by underlying physical phenomena such as melting, phase transitions, diffusion, and dislocation motion. With regards to fault mechanics, we begin by showing how co-seismic weakening mechanisms driven by elevated pore fluid pressures lead to micron-scale strain localization during an earthquake. We solve for the localized zone thickness for a range of fault temperatures, test these predictions using numerical simulations, and show how the onset of localization accelerates fault weakening. Next we present the first solutions to account for thermal decomposition reactions during a dynamic rupture, showing that the activation of thermal decomposition may lead to a larger slip duration and total slip. Finally we present a new set of experiments studying flash heating of serpentinite, highlighting the dependence of friction on normal stress and the presence of gouge, and producing the first model to explain the hysteresis commonly observed in flash heating experiments. With regards to ice stream shear margins, we begin by extending the work of Perol and Rice [2011] to study the formation of temperate ice in shear margins, and quantify the total melt that may be generated within the shear margins. We conclude by investigating how the presence of such a channel alters the stress on and strength of the undeforming bed in the shear margin, showing that the transition from a deforming to an undeforming bed across a channel is stable when the water flux in the channel exceeds a critical value.

  20. Improved in Situ Space Weather Data Services from the NOAA National Geophysical Data Center

    NASA Astrophysics Data System (ADS)

    Rodriguez, J. V.; Denig, W. F.; Green, J. C.; Lotoaniu, T. M.; McGuire, R. E.; Redmon, R. J.; Rowland, W. F.; Turner, D. L.; Weigel, R. S.; Wilkinson, D. C.

    2014-12-01

    The international space weather enterprise relies heavily on in situ plasma, particle and magnetic field measurements from U. S. weather satellites. This year marks the 40th anniversary of the launch of the first U. S. geostationary weather satellite (SMS-1), which carried the direct ancestor of the current GOES Space Environment Monitor (SEM) suite. The GOES space weather observations support the issuance of real-time alerts by the NOAA Space Weather Prediction Center (SWPC). The publicly-available archive of space weather observations at the NOAA National Geophysical Data Center (NGDC) includes NOAA geostationary observations since 1974 and POES/MetOp and Air Force DMSP polar-orbiting observations since 1978 and 1982, respectively. This archive supports the retrospective aspect of the space weather enterprise, which includes model development and anomaly resolution efforts. Over the last several years, NGDC has made a concerted effort to improve its data services in cooperation with the broader space weather community. These improvements include (1) taking over the processing of existing products, (2) creating science-quality versions of existing products, (3) developing new products, (4) improving the distribution of these products, and (5) validating products via on-orbit cross-comparisons. Complementing this retrospective role, NGDC is also responsible for the next-generation GOES-R space weather instrument science and is working as part of the GOES-R calibration/validation group to ensure that these new instruments and their products meet NOAA's requirements. This presentation will survey NGDC's efforts in each of these areas, including (1) POES/MetOp SEM-2 fluxes and radiation belt indices, (2) GOES fluxes with data quality flags and error bars, (3) in situ products from GOES-R(S,T,U), (4) cooperative distribution efforts with the NASA Space Physics Data Facility (SPDF) and the Space Physics Environmental Data Analysis System (SPEDAS), and (5) inter-calibrations of solar energetic proton fluxes and of magnetospheric electron fluxes.

  1. A graphical weather system design for the NASA transport systems research vehicle B-737

    NASA Technical Reports Server (NTRS)

    Scanlon, Charles H.

    1992-01-01

    A graphical weather system was designed for testing in the NASA Transport Systems Research Vehicle B-737 airplane and simulator. The purpose of these tests was to measure the impact of graphical weather products on aircrew decision processes, weather situation awareness, reroute clearances, workload, and weather monitoring. The flight crew graphical weather interface is described along with integration of the weather system with the flight navigation system, and data link transmission methods for sending weather data to the airplane.

  2. Relativity Based on Physical Processes Rather Than Space-Time

    NASA Astrophysics Data System (ADS)

    Giese, Albrecht

    2013-09-01

    Physicists' understanding of relativity and the way it is handled is at present dominated by the interpretation of Albert Einstein, who related relativity to specific properties of space and time. The principal alternative to Einstein's interpretation is based on a concept proposed by Hendrik A. Lorentz, which uses knowledge of classical physics to explain relativistic phenomena. In this paper, we will show that on the one hand the Lorentz-based interpretation provides a simpler mathematical way of arriving at the known results for both Special and General Relativity. On the other hand, it is able to solve problems which have remained open to this day. Furthermore, a particle model will be presented, based on Lorentzian relativity, which explains the origin of mass without the use of the Higgs mechanism, based on the finiteness of the speed of light, and which provides the classical results for particle properties that are currently only accessible through quantum mechanics.

  3. Processes in karst systems, physics, chemistry, and geology

    SciTech Connect

    Dreybrodt, W.

    1988-01-01

    Dreybrodt deals quantitatively with many of the chemical and hydrological processes involved in the formation of karst systems. The book is divided into 3 major parts. The first part develops the basic chemical and fluid-flow principles needed in modeling karst systems. The second part investigates the experimental kinetics of calcite dissolution and precipitation and applies the resulting kinetic laws to the modeling of these processes in systems both open and closed to carbon dioxide. The last part of the book includes a qualitative examination of karst systems, quantitative modeling of the development of karst features, and an examination and modeling of the growth of spelotherms in caves.

  4. Aerosol physical properties and their impact on climate change processes

    NASA Astrophysics Data System (ADS)

    Strzalkowska, Agata; Zielinski, Tymon; Petelski, Tomasz; Makuch, Przemyslaw; Pakszys, Paulina; Markuszewski, Piotr; Piskozub, Jacek; Drozdowska, Violetta; Gutowska, Dorota; Rozwadowska, Anna

    2013-04-01

    Characterizing aerosols involves the specification of not only their spatial and temporal distributions but their multi-component composition, particle size distribution and physical properties as well. Due to their light attenuation and scattering properties, aerosols influence radiance measured by satellite for ocean color remote sensing. Studies of marine aerosol production and transport are important for many earth sciences such as cloud physics, atmospheric optics, environmental pollution studies, and interaction between ocean and atmosphere. It was one of the reasons for the growth in the number of research programs dealing with marine aerosols. Sea salt aerosols are among the most abundant components of the atmospheric aerosol, and thus it exerts a strong influence on radiation, cloud formation, meteorology and chemistry of the marine atmosphere. An accurate understanding and description of these mechanisms is crucial to modeling climate and climate change. This work provides information on combined aerosol studies made with lidars and sun photometers onboard the ship and in different coastal areas. We concentrate on aerosol optical thickness and its variations with aerosol advections into the study area. We pay special attention to the problem of proper data collection and analyses techniques. We showed that in order to detect the dynamics of potential aerosol composition changes it is necessary to use data from different stations where measurements are made using the same techniques. The combination of such information with air mass back-trajectories and data collected at stations located on the route of air masses provides comprehensive picture of aerosol variations in the study area both vertically and horizontally. Acknowledgements: The support for this study was provided by the project Satellite Monitoring of the Baltic Sea Environment - SatBałtyk founded by European Union through European Regional Development Fund contract No. POIG 01.01.02-22-011/09. It has also been made within the framework of the NASA/AERONET Program.

  5. Coupling physical and biogeochemical processes in sea ice

    NASA Astrophysics Data System (ADS)

    Tedesco, L.; Vichi, M.; Haapala, J.; Stipa, T.

    2009-04-01

    In the last decades the scientific community has been making lot of efforts to understand the physics of sea ice. We currently have a good knowledge of the sea ice dynamics and thermodynamics and of their temporal and spatial variability. Sea ice biogeochemistry is instead largely unknown. There are only sparse localized observations and little knowledge of the functioning of sea ice biogeochemistry at larger scales. Modelling becomes then a necessary tool to qualify and quantify the role of sea ice biogeochemistry in the ocean dynamics. We used a different approach with respect to the previous attempts of modelling the sea ice biogeochemistry and in particular of its primary production. The central concept is the definition of the Biologically-Active-Layer (BAL), which is the time-varying fraction of sea ice that is continuously connected to the ocean via brines pockets and channels. A 1-D Enhanced Sea Ice halo-thermodynamic Model (ESIM2) is able to simulate the key physical properties of the BAL (thickness, temperature, brines salinity and volume, sea ice bulk salinity and irradiance), which are passed to the new implementation of the Biogeochemical Flux Model in sea ice (BFM-SI). The new BFM-SI uses those information to simulate the physiological and ecological response of the biological community in sea ice. The new model is also coupled to the pelagic BFM through the exchange of organic and inorganic matter at the boundaries between the two systems . This is done by computing the entrapment of matter and gases when sea ice grows and release to the ocean when sea ice melts and it is thus totally mass-conserving. The implementation of the BFM-SI model and coupling structure in General Circulation Models will add a new component to GCMs (and in general to Earth System Models), which will be finally able to estimate globally the role and importance of sea ice biogeochemistry in the global carbon cycle.

  6. Simulation of Forming Process as an Educational Tool Using Physical Modeling

    ERIC Educational Resources Information Center

    Abdullah, A. B.; Muda, M. R.; Samad, Z.

    2008-01-01

    Metal forming process simulation requires a very high cost including the cost for dies, machine and material and tight process control since the process involve very huge pressure. A physical modeling technique is developed and initiates a new era of educational tool of simulating the process effectively. Several publications and findings have

  7. Speaking and Speaking Education as Physical Process in Turkish Education

    ERIC Educational Resources Information Center

    Kurudayioglu, Mehmet

    2011-01-01

    Speaking is sending the message which is desired to be transferred to another one with vocal organs and produced by complicated operations in the brain. Speaking, which is a complicated process, is the most common and important means of communication among people. Speaking, which has essential place both individually and socially, affects success

  8. Processing and physical properties of chia-oat hydrocolloids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chia-oat dry blended composites and their processed hydrocolloids containing omega-3 and omega-6 fatty acids from chia along with soluble ß-glucan from three oat products were developed and studied. Chia’s omega-3 fatty acids and soluble ß-glucan from oat products are recognized for preventing heart...

  9. Physical Education Resources, Class Management, and Student Physical Activity Levels: A Structure-Process-Outcome Approach to Evaluating Physical Education Effectiveness

    PubMed Central

    Bevans, Katherine B.; Fitzpatrick, Leslie-Anne; Sanchez, Betty M.; Riley, Anne W.; Forrest, Christopher

    2011-01-01

    BACKGROUND This study was conducted to empirically evaluate specific human, curricular, and material resources that maximize student opportunities for physical activity during physical education (PE) class time. A structure-process-outcome model was proposed to identify the resources that influence the frequency of PE and intensity of physical activity during PE. The proportion of class time devoted to management was evaluated as a potential mediator of the relations between resource availability and student activity levels. METHODS Data for this cross-sectional study were collected from interviews conducted with 46 physical educators and the systematic observation of 184 PE sessions in 34 schools. Regression analyses were conducted to test for the main effects of resource availability and the mediating role of class management. RESULTS Students who attended schools with a low student-to-physical educator ratio had more PE time and engaged in higher levels of physical activity during class time. Access to adequate PE equipment and facilities was positively associated with student activity levels. The availability of a greater number of physical educators per student was found to impact student activity levels by reducing the amount of session time devoted to class management. CONCLUSION The identification of structure and process predictors of student activity levels in PE will support the allocation of resources and encourage instructional practices that best support increased student activity levels in the most cost-effective way possible. Implications for PE policies and programs are discussed. PMID:21087253

  10. Evidence of Space Weathering in Regolith Breccias II: Asteroidal Regolith Breccias

    NASA Technical Reports Server (NTRS)

    Noble, Sarah K.; Keller, Lindsay P.; Pieters, Carle M.

    2011-01-01

    Space weathering products, such as agglutinates and nanophaase iron-bearing rims are easily preserved through lithifcation in lunar regolith breccias, thus such products, if produced, should be preserved in asteroidal regotith breccias as well. A study of representative regolith breecia meteorites, Fayetteville (H4) and Kapoeta (howardite), was undertaken to search for physical evidence of space weathering on asteroids. Amorphous or npFe(sup 0)-bearing rim cannot be positively identified in Fayetteville, although possible glass rims were found. Extensive friction melt was discovered in the meteorite that is difficult to differentiate from weathered materials. Several melt products, including spherules and agglutinates, as well as one irradiated rim and one possible npFe(sup 0)-bearing rim were identified in Kapoeta. The existence of these products suggests that lunar-like space weathering processes are, or have been, active on asteroids.

  11. Asteroids: Does Space Weathering Matter?

    NASA Technical Reports Server (NTRS)

    Gaffey, Michael J.

    2001-01-01

    The interpretive calibrations and methodologies used to extract mineralogy from asteroidal spectra appear to remain valid until the space weathering process is advanced to a degree which appears to be rare or absent on asteroid surfaces. Additional information is contained in the original extended abstract.

  12. Cosmochemical implications of the physical processing of cometary nuclei

    SciTech Connect

    McSween, H.Y. Jr. ); Weissman, P.R. )

    1989-12-01

    Comets are not necessarily pristine nebular and interstellar material, despite a common perception to that effect. Alteration processes may occur during comet formation in the outer planet region, during their dispersal to or residence within the Oort cloud, and after their return to the planetary region. Processes that may have significantly modified cometary nuclei include heating, impacts, and irradiation. Possible consequences include phase changes in ices, hydration reactions in silicates, synthesis of organic compounds, collisional disruption and re-accretion, shock and irradiation effects in minerals and ices, cosmogenic nuclide formation, redistribution or loss of volatiles, and formation of a refractory veneer. A model of cometary nuclei that emerges from these considerations provides a framework for understanding observations of comets and future samples.

  13. A physical interpretation for the natural photosynthetic process

    PubMed Central

    Hill, Robert; Rich, Peter R.

    1983-01-01

    The efficiency of the process of photosynthesis is shown to depend on the molecular conversion of power. This requires establishment of a discipline that is now implicit in current thought and that offers a definition of relationship between equilibrium state and power. The quantum aspect for the microscopic process is different from the macroscopic system idealized as the heat engine and is required for the interpretation of molecular machinery. By using three postulates the ideal maximal efficiency for the molecular energy conversion is calculated from the data, which are assembled in the form of the Z scheme for photosynthesis. The observed and the calculated efficiencies for a green plant are substantially in agreement. PMID:16593282

  14. Cosmochemical implications of the physical processing of cometary nuclei

    NASA Technical Reports Server (NTRS)

    Mcsween, Harry Y., Jr.; Weissman, Paul R.

    1989-01-01

    Comets are not necessarily pristine nebular and interstellar material, despite a common perception to that effect. Alteration processes may occur during comet formation in the outer planet region, during their dispersal to or residence within the Oort cloud, and after their return to the planetary region. Processes that may have significantly modified cometary nuclei include heating, impacts, and irradiation. Possible consequences include phase changes in ices, hydration reactions in silicates, synthesis of organic compounds, collisional disruption and re-accretion, shock and irradiation effects in minerals and ices, cosmogenic nuclide formation, redistribution or loss of volatiles, and formation of a refractory veneer. A model of cometary nuclei that emerges from these considerations provides a framework for understanding observations of comets and future samples.

  15. Analogy between electrochemical oscillations and quantum physical processes

    NASA Astrophysics Data System (ADS)

    Grzanna, J.; Lewerenz, H. J.

    2014-03-01

    In (photo) electrochemical oscillations, the discretization of phase oscillators leads to a sequence of time dependent oscillator density functions which describe the passing of the oscillators through their minimum at each cycle. Two consecutive oscillator density functions are connected by a Markov process represented by a linear integral equation of second order which is homogeneous in the case of sustained oscillations. The kernel of the integral equation is a normalized Greens Function and represents the probability density for the periods of the oscillators. Both together, the oscillator density function and the two-dimensional probability density for the periods of the oscillators define a random walk. The relation of the model to the holographic principle is discussed briefly. Further, a detailed analysis of a kernel of the integral equation leads to a frequency distribution g for the period length. Additionally, it is possible to determine the energy E in dependence on the period length from the electrochemical process. The product g E shows qualitatively the same behaviour as the radiation of a black body, indicating that the discretization of phase oscillators, when represented by phase space analysis, show an analogy to quantum processes.

  16. Beyond the Weather Chart: Weathering New Experiences.

    ERIC Educational Resources Information Center

    Huffman, Amy Bruno

    1996-01-01

    Describes an early childhood educator's approach to teaching children about rain, rainbows, clouds, precipitation, the sun, air, and wind. Recommends ways to organize study topics and describes experiments that can help children better understand the different elements of weather. (MOK)

  17. Weatherization and Intergovernmental Program - Weatherization Assistance Program

    SciTech Connect

    2010-06-01

    The U.S. Department of Energy’s (DOE) Weatherization Assistance Program reduces energy costs for low-income households by increasing the energy efficiency of their homes, while ensuring their health and safety.

  18. Physical processes affecting the sedimentary environments of Long Island Sound

    USGS Publications Warehouse

    Signell, R.P.; Knebel, H. J.; List, J.H.; Farris, A.S.

    1997-01-01

    A modeling study was undertaken to simulate the bottom tidal-, wave-, and wind-driven currents in Long Island Sound in order to provide a general physical oceanographic framework for understanding the characteristics and distribution of seafloor sedimentary environments. Tidal currents are important in the funnel-shaped eastern part of the Sound, where a strong gradient of tidal-current speed was found. This current gradient parallels the general westward progression of sedimentary environments from erosion or non-deposition, through bedload transport and sediment sorting, to fine-grained deposition. Wave-driven currents, meanwhile, appear to be important along the shallow margins of the basin, explaining the occurrence of relatively coarse sediments in regions where tidal currents alone are not strong enough to move sediment. Finally, westerly wind events are shown to locally enhance bottom currents along the axial depression of the sound, providing a possible explanation for the relatively coarse sediments found in the depression despite tide- and wave-induced currents below the threshold of sediment movement. The strong correlation between the near-bottom current intensity based on the model results and the sediment response as indicated by the distribution of sedimentary environments provides a framework for predicting the long-term effects of anthropogenic activities.

  19. Phytoplankton photoadaptation related to some frontal physical processes

    NASA Astrophysics Data System (ADS)

    Claustre, H.; Kerherv, P.; Marty, J.-C.; Prieur, L.

    1994-08-01

    Using phytoplankton pigments as biomarkers, we studied light adaptation of phytoplankton communities in a geostrophic front and the surrounding area by (i) onboard kinetic experiments and (ii) detailed analyses of the vertical profiles of a selected photoadaptive index. Kinetic experiments, in which populations were subjected to a sudden light shift (from high to low irradiances and vice versa), clearly demonstrated that frontal phytoplankton populations, especially diatoms (fucoxanthin) are less affected by light shifts than the populations of the adjacent oligotrophic zones. Kinetic experiments also showed that the ratio diadinoxanthin/Chl. a, positively correlated with light intensity, is a useful index to characterize and identify certain time scales of photoadaptation in microalgae. The rate of change of this index was estimated around 0.5 h -1, with significantly higher values for the frontal communities compared to the adjacent area. The rate of variation of this ratio, deduced from in situ measurements, is however one order of magnitude lower than the rate obtained from kinetic experiments. These two approaches allowed us (i) to compare different populations and (ii) to define an upper limit of the adaptation rates. Typical in situ profiles of the diadinoxanthin/Chl. a ratio showed obvious day-night variations. Relative anomalies in these profiles were interpretated in terms of "light histories" of phytoplankton communities and compared with potential causal physical motions (diffusion or advection).

  20. [Suicide and weather].

    PubMed

    Breuer, H W; Fischbach-Breuer, B R; Breuer, J; Goeckenjan, G; Curtius, J M

    1984-11-01

    In 151 patients, admitted to an intensive care unit after attempted suicide, the possible influence of weather at the time of the attempt was analysed retrospectively. The "biosynoptic daily analysis" of the German Weather Service provided the weather data. There was a 5% and 1%, respectively, significant level for the positive correlation between the time of the attempted suicide and the weather parameters "stable upslide, labile upslide, fog and thunderstorm" and the summarized parameters "warm air, upslide and weather drier than on the two preceding days". Significantly fewer attempts than expected occurred when the weather description was "low pressure and trough situation, labile ground layer--upslide above" and the summarized parameters "subsidence or downslide motion". Besides the individual factors such as the reaction to conflicts and the spectrum of reactions, exogenous factors like weather must be considered as important for the time of suicidal attempt. PMID:6499669

  1. Solar and Space Physics PhD Production and Job Availability: Implications for the Future of the Space Weather Research Workforce

    NASA Astrophysics Data System (ADS)

    Moldwin, M.; Morrow, C. A.; Moldwin, L. A.; Torrence, J.

    2012-12-01

    To assess the state-of-health of the field of Solar and Space Physics an analysis of the number of Ph.D.s produced and number of Job Postings each year was done for the decade 2001-2010. To determine the number of Ph.D's produced in the field, the University of Michigan Ph.D. Dissertation Archive (Proquest) was queried for Solar and Space Physics dissertations produced in North America. The field generated about 30 Ph.D. per year from 2001 to 2006, but then saw the number increase to 50 to 70 per year for the rest of the decade. Only 14 institutions account for the majority of Solar and Space Physics PhDs. To estimate the number of jobs available each year in the field, a compilation of the job advertisements listed in the American Astronomical Society's Solar Physics Division (SPD) and the American Geophysical Union's Space Physics and Aeronomy (SPA) electronic newsletters was done. The positions were sorted into four types (Faculty, Post-doctoral Researcher, and Scientist/Researcher or Staff), institution type (academic, government lab, or industry) and if the position was located inside or outside the United States. Overall worldwide, 943 Solar and Space Physics positions were advertised over the decade. Of this total, 52% were for positions outside the US. Within Solar Physics, 44% of the positions were in the US, while in Space Physics 57% of the positions were for US institutions. The annual average for positions in the US were 26.9 for Solar Physics and 31.5 for Space Physics though there is much variability year-to-year particularly in Solar Physics positions outside the US. A disconcerting trend is a decline in job advertisements in the last two years for Solar Physics positions and between 2009 and 2010 for Space Physics positions. For both communities within the US in 2010, the total job ads reached their lowest levels in the decade (14), approximately half the decadal average number of job advertisements.

  2. Physical-chemical treatment of tar-sand processing wastewater

    SciTech Connect

    King, P.H.

    1982-07-01

    This final report for Phase I summarizes work done to determine the ability of several coagulants to contribute significantly in the treatment of selected tar sand wastewaters. The coagulation process must be considered as one possible step in a treatment scheme to reduce pollutants in these wastewaters and lead to a water quality acceptable for reuse or disposal. Two wastewaters were provided by the Laramie Energy Technology Center (LETC). The primary emphasis in this study was focused on a representative steam flooding wastewater designated in the report as TARSAND 1S. The coagulation study in which treatment of this wastewater was the prime goal is described in full detail in the thesis entitled Chemical Coagulation of Steam Flooding Tar Sand Wastewaters. This thesis, written by Mr. Omar Akad, is included as Appendix A in this report. A representative combustion wastewater, designated as TARSAND 2C, was also provided by LETC. This wastewater was characteristically low in suspended solids and after initial screening experiments were conducted, it was concluded that coagulation was relatively ineffective in the treatment of TARSAND 2C. Hence, efforts were concentrated on the parametric evaluation of coagulation of TARSAND 1S. The objectives for the research conducted under Phase I were: (1) to compare the effectiveness of lime, alum, ferric chloride and representative synthetic organic polymers in reducing suspended solids and total organic carbon (TOC) from TARSAND 1S wastewater; (2) to determine the effects of pH, coagulant aids, and mixing conditions on the coagulation process; (3) to determine the relative volume of sludge produced from each selected coagulation process.

  3. Optimal assimilation for ionospheric weather Theoretical aspect

    NASA Astrophysics Data System (ADS)

    Guo, Jian-Shan; Shang, She-Ping; Shi, Jiankui; Zhang, Manlian; Luo, Xigui; Zheng, Hong

    2003-04-01

    Observation, specification and prediction of ionospheric weather are the key scientific pursuits of space physicists, which largely based on an optimal assimilation system. The optimal assimilation system, or commonly called data assimilation system, consists of dynamic process, observation system and optimal estimation procedure. We attempt to give a complete framework in this paper under which the data assimilation procedure carries through. We discuss some crucial issues of data assimilation as follows: modeling a dynamic system for ionospheric weather; state estimation for static or steady system in sense of optimization and likelihood; state and its uncertainty estimation for dynamic process. Meanwhile we also discuss briefly the observability of an observation system; system parameter identification. Some data assimilation procedures existed at present are reviewed in the framework of this paper. As an example, a second order dynamic system is discussed in more detail to illustrate the specific optimal assimilation procedure, ranging from modeling the system, state and its uncertainty calculation, to the quantitatively integration of dynamic law, measurement to significantly reduce the estimation error. The analysis shows that the optimal assimilation model, with mathematical core of optimal estimation, differs from the theoretical, empirical and semi-empirical models in assimilating measured data, being constrained by physical law and being optimized respectively. The data assimilation technique, due to its optimization and integration feature, could obtain better accurate results than those obtained by dynamic process, measurement or their statistical analysis alone. The model based on optimal assimilation meets well with the criterion of the model or algorithm assessment by space weather metrics. More attention for optimal assimilation procedure creation should be paid to transition matrix finding, which is usually not easy for practical space weather system. High performance computing hardware and software studies should be promoted further so as to meet the requirement of large storage and extensive computation in the optimal estimation. The discussion in this paper is appropriate for the static or steady state or transition process of dynamic system. Many phenomena in space environment are unstable and chaos. So space environment study should include and integrate these two branches of learning.

  4. Chemical weathering and CO? consumption in the Lower Mekong River.

    PubMed

    Li, Siyue; Lu, X X; Bush, Richard T

    2014-02-15

    Data on river water quality from 42 monitoring stations in the Lower Mekong Basin obtained during the period 1972-1996 was used to relate solute fluxes with controlling factors such as chemical weathering processes. The total dissolved solid (TDS) concentration of the Lower Mekong varied from 53 mg/L to 198 mg/L, and the median (114 mg/L) was compared to the world spatial median value (127 mg/L). Total cationic exchange capacity (Tz(+)) ranged from 729 to 2,607 ?molc/L, and the mean (1,572 ?molc/L) was 1.4 times higher than the world discharge-weighted average. Calcium and bicarbonate dominated the annual ionic composition, accounting for ~70% of the solute load that equalled 41.210(9)kg/y. TDS and major elements varied seasonally and in a predictable way with river runoff. The chemical weathering rate of 37.7t/(km(2)y), with respective carbonate and silicate weathering rates of 27.5t/(km(2) y) (13.8mm/ky) and 10.2t/(km(2) y) (3.8mm/ky), was 1.5 times higher than the global average. The CO2 consumption rate was estimated at 19110(3)molCO2/(km(2)y) for silicate weathering, and 28610(3)molCO2/(km(2)y) by carbonate weathering. In total, the Mekong basin consumed 22810(9)molCO2/y and 15210(9)molCO2/y by the combined weathering of carbonate and silicate, constituting 1.85% of the global CO2 consumption by carbonate weathering and 1.75% by silicates. This is marginally higher than its contribution to global water discharge ~1.3% and much higher than (more than three-fold) its contribution to world land surface area. Remarkable CO2 consumed by chemical weathering (38010(9)mol/y) was similar in magnitude to dissolved inorganic carbon as HCO3(-) (37010(9)mol/y) exported by the Mekong to the South China Sea. In this landscape, atmospheric CO2 consumption by rock chemical weathering represents an important carbon sink with runoff and physical erosion controlling chemical erosion. PMID:24291559

  5. Physical Processes for Driving Ionospheric Outflows in Global Simulations

    NASA Technical Reports Server (NTRS)

    Moore, Thomas Earle; Strangeway, Robert J.

    2009-01-01

    We review and assess the importance of processes thought to drive ionospheric outflows, linking them as appropriate to the solar wind and interplanetary magnetic field, and to the spatial and temporal distribution of their magnetospheric internal responses. These begin with the diffuse effects of photoionization and thermal equilibrium of the ionospheric topside, enhancing Jeans' escape, with ambipolar diffusion and acceleration. Auroral outflows begin with dayside reconnexion and resultant field-aligned currents and driven convection. These produce plasmaspheric plumes, collisional heating and wave-particle interactions, centrifugal acceleration, and auroral acceleration by parallel electric fields, including enhanced ambipolar fields from electron heating by precipitating particles. Observations and simulations show that solar wind energy dissipation into the atmosphere is concentrated by the geomagnetic field into auroral regions with an amplification factor of 10-100, enhancing heavy species plasma and gas escape from gravity, and providing more current carrying capacity. Internal plasmas thus enable electromagnetic driving via coupling to the plasma, neutral gas and by extension, the entire body " We assess the Importance of each of these processes in terms of local escape flux production as well as global outflow, and suggest methods for their implementation within multispecies global simulation codes. We complete 'he survey with an assessment of outstanding obstacles to this objective.

  6. Processing of speech signals for physical and sensory disabilities.

    PubMed Central

    Levitt, H

    1995-01-01

    Assistive technology involving voice communication is used primarily by people who are deaf, hard of hearing, or who have speech and/or language disabilities. It is also used to a lesser extent by people with visual or motor disabilities. A very wide range of devices has been developed for people with hearing loss. These devices can be categorized not only by the modality of stimulation [i.e., auditory, visual, tactile, or direct electrical stimulation of the auditory nerve (auditory-neural)] but also in terms of the degree of speech processing that is used. At least four such categories can be distinguished: assistive devices (a) that are not designed specifically for speech, (b) that take the average characteristics of speech into account, (c) that process articulatory or phonetic characteristics of speech, and (d) that embody some degree of automatic speech recognition. Assistive devices for people with speech and/or language disabilities typically involve some form of speech synthesis or symbol generation for severe forms of language disability. Speech synthesis is also used in text-to-speech systems for sightless persons. Other applications of assistive technology involving voice communication include voice control of wheelchairs and other devices for people with mobility disabilities. Images Fig. 4 PMID:7479816

  7. Controls on chemical weathering kinetics: Implications from modelling of stable isotope fractionations

    NASA Astrophysics Data System (ADS)

    Bickle, M. J.; Tipper, E.; De La Rocha, C. L.; Galy, A.; Li, S.

    2013-12-01

    The kinetic controls on silicate chemical weathering rates are thought central to the feedback process that regulates global climate on geological time scales. However the nature and magnitude of these kinetic controls are controversial. In particular the importance of physical erosion rates is uncertain with some arguing that there is an upper limit on chemical weathering fluxes irrespective of physical erosion rates (e.g. Dixon and von Blackenburg, 2012). Others argue that it is the hydrology of catchments which determines flow path lengths and fluid residence times which are critical to chemical weathering fluxes (e.g. Maher, 2011). Understanding these physical controls is essential to predicting how chemical weathering fluxes will respond the key climatic controls. Chemical weathering fluxes are best estimated by the integrated riverine outputs from catchments as soil profiles may not integrate all the flow paths. However the interpretation of chemical weathering processes based solely on flux data is difficult, because of both the multiple processes acting and multiple phases dissolving that contribute to these fluxes. Fractionations of stable isotopes of the soluble elements including Li, Mg, Si and Ca should place additional constraints on chemical weathering processes. Here we use a simple reactive-transport model to interpret stable isotope fractionations. Although still a simplification of the natural system, this offers a much closer representation than simple batch and Rayleigh models. The isotopic fractionations are shown to be a function of the ratio of the amount of the element supplied by mineral dissolution to that lost to secondary mineral formation and the extent of reaction down the flow path. The modelling is used to interpret the evolution of dissolved Li, Mg and Si-isotope ratios in Ganges river system. The evolution of Si isotopic ratios in the rapidly eroding Himalayan catchments is distinct from that in the flood planes. Critically the extent of the isotopic fractionations is a measure of the approach of the system to chemical equilibrium, a key indicator of the temperature sensitivity of the chemical weathering rate and hence important to understanding the climate-weathering feedback. Dixon JL, & von Blanckenburg, F, (2012) Soils as pacemakers and limiters of global silicate weathering. Comptes Rendus Geoscience, 344:597-609. Maher, K (2011) The role of fluid residence time and topographic scales in determining chemical fluxes from landscapes. Earth and Planetary Science Letters, 312:48-58.

  8. Reviews Book: Marie Curie and Her Daughters Resource: Cumulus Equipment: Alpha Particle Scattering Apparatus Equipment: 3D Magnetic Tube Equipment: National Grid Transmission Model Book: Einstein's Physics Equipment: Barton's Pendulums Equipment: Weather Station Web Watch

    NASA Astrophysics Data System (ADS)

    2013-09-01

    WE RECOMMEND Marie Curie and Her Daughters An insightful study of a resilient and ingenious family and their achievements Cumulus Simple to install and operate and with obvious teaching applications, this weather station 'donationware' is as easy to recommend as it is to use Alpha Particle Scattering Apparatus Good design and construction make for good results National Grid Transmission Model Despite its expense, this resource offers excellent value Einstein's Physics A vivid, accurate, compelling and rigorous treatment, but requiring an investment of time and thought WORTH A LOOK 3D Magnetic Tube Magnetic fields in three dimensions at a low cost Barton's Pendulums A neat, well-made and handy variant, but not a replacement for the more traditional version Weather Station Though not as robust or substantial as hoped for, this can be put to good use with the right software WEB WATCH An online experiment and worksheet are useful for teaching motor efficiency, a glance at CERN, and NASA's interesting information on the alpha-magnetic spectrometer and climate change

  9. Radon: Chemical and physical processes associated with its distribution

    SciTech Connect

    Castleman, A.W. Jr.

    1992-01-01

    Assessing the mechanisms which govern the distribution, fate, and pathways of entry into biological systems, as well as the ultimate hazards associated with the radon progeny and their secondary reaction products, depends on knowledge of their chemistry. Our studies are directed toward developing fundamental information which will provide a basis for modeling studies that are requisite in obtaining a complete picture of growth, attachment to aerosols, and transport to the bioreceptor and ultimate incorporation within. Our program is divided into three major areas of research. These include measurement of the determination of their mobilities, study of the role of radon progeny ions in affecting reactions, including study of the influence of the degree of solvation (clustering), and examination of the important secondary reaction products, with particular attention to processes leading to chemical conversion of either the core ions or the ligands as a function of the degree of clustering.

  10. CO2-ECBM related coupled physical and mechanical transport processes

    NASA Astrophysics Data System (ADS)

    Gensterblum, Y.; Sartorius, M.; Busch, A.; Krooss, B. M.; Littke, R.

    2012-12-01

    The interrelation of cleat transport processes and mechanical properties was investigated by permeability tests at different stress levels (60% to 130% of in-situ stress) with sorbing (CH4, CO2) and inert gases (N2, Ar, He) on a subbituminous A coal from the Surat Basin, Queensland Australia (figure). From the flow tests under controlled triaxial stress conditions the Klinkenberg-corrected "true" permeability coefficients and the Klinkenberg slip factors were derived. The "true"-, absolute or Klinkenberg-corrected permeability depends on gas type. Following the approach of Seidle et al. (1992) the cleat volume compressibility (cf) was calculated from observed changes in apparent permeability upon variation of external stress (at equal mean gas pressures). The observed effects also show a clear dependence on gas type. Due to pore or cleat compressibility the cleat aperture decreases with increasing effective stress. Vice versa, with increasing mean pore pressure at lower confining pressure an increase in permeability is observed, which is attributed to a widening of cleat aperture. Non-sorbing gases like helium and argon show higher apparent permeabilities than sorbing gases like methane and CO2. Permeability coefficients measured with successively increasing mean gas pressures were consistently lower than those determined at decreasing mean gas pressures. The kinetics of matrix transport processes were studied by sorption tests on different particle sizes at various moisture contents and temperatures (cf. Busch et al., 2006). Methane uptake rates were determined from the pressure decline curves recorded for each particle-size fraction, and "diffusion coefficients" were calculated using several unipore and bidisperse diffusion models. While the CH4 sorption capacity of moisture-equilibrated coals was significantly lower (by 50%) than that of dry coals, no hysteresis was observed between sorption and desorption on dry and moisture-equilibrated samples and the sorption isotherms recorded for different particle sizes were essentially identical. The CH4 uptake rates were lower by a factor of two for moist coals than for dry coals. Busch, A., Gensterblum, Y., Krooss, B.M. and Siemons, N., 2006. Investigation of high-pressure selective adsorption/desorption behaviour of CO2 and CH4 on coals: An experimental study. International Journal of Coal Geology, 66(1-2): 53-68. Seidle, J.P., Jeansonne, M.W. and Erickson, D.J., 1992. Application of Matchstick Geometry to Stress-Dependent Permeability in Coals, SPE Rocky Mountain Regional Meeting, Casper, Wyoming.

  11. Application of green IT for physics data processing at INCDTIM

    NASA Astrophysics Data System (ADS)

    Farcas, Felix; Trusca, Radu; Albert, Stefan; Szabo, Izabella; Popeneciu, Gabriel

    2012-02-01

    Green IT is the next generation technology used in all datacenter around the world. Its benefit is of economic and financial interest. The new technologies are energy efficient, reduce cost and avoid potential disruptions to the existing infrastructure. The most important problem appears at the cooling systems which are the most important in the functionality of a datacenter. Green IT used in Grid Network will benefit the environment and is the next phase in computer infrastructure that will fundamentally change the way we think about and use computing power. At the National Institute for Research and Development of Isotopic and Molecular Technologies Cluj-Napoca (INCDTIM) we have implemented such kind of technology and its support helped us in processing multiple data in different domains, which brought INCDTIM on the major Grid domain with the RO-14-ITIM Grid site. In this paper we present benefits that the new technology brought us and the result obtained in the last year after the implementation of the new green technology.

  12. A Model of the Creative Process Based on Quantum Physics and Vedic Science.

    ERIC Educational Resources Information Center

    Rose, Laura Hall

    1988-01-01

    Using tenets from Vedic science and quantum physics, this model of the creative process suggests that the unified field of creation is pure consciousness, and that the development of the creative process within individuals mirrors the creative process within the universe. Rational and supra-rational creative thinking techniques are also described.…

  13. A Model of the Creative Process Based on Quantum Physics and Vedic Science.

    ERIC Educational Resources Information Center

    Rose, Laura Hall

    1988-01-01

    Using tenets from Vedic science and quantum physics, this model of the creative process suggests that the unified field of creation is pure consciousness, and that the development of the creative process within individuals mirrors the creative process within the universe. Rational and supra-rational creative thinking techniques are also described.

  14. CO2-ECBM related coupled physical and mechanical transport processes

    NASA Astrophysics Data System (ADS)

    Gensterblum, Yves; Satorius, Michael; Busch, Andreas; Krooß, Bernhard

    2013-04-01

    The interrelation of cleat transport processes and mechanical properties was investigated by permeability tests at different stress levels (60% to 130% of in-situ stress) with sorbing (CH4, CO2) and inert gases (N2, Ar, He) on a sub bituminous A coal from the Surat Basin, Queensland Australia. From the flow tests under controlled triaxial stress conditions the Klinkenberg-corrected "true" permeability coefficients and the Klinkenberg slip factors were derived. The "true"-, absolute or Klinkenberg corrected permeability shows a gas type dependence. Following the approach of Seidle et al. (1992) the cleat volume compressibility (cf) was calculated from observed changes in apparent permeability upon variation of external stress (at equal mean gas pressures). The observed effects also show a clear dependence on gas type. Due to pore or cleat compressibility the cleat aperture decreases with increasing effective stress. Vice versa we observe with increasing mean pressure at lower confining pressure an increase in permeability which we attribute to a cleat aperture widening. The cleat volume compressibility (cf) also shows a dependence on the mean pore pressure. Non-sorbing gases like helium and argon show higher apparent permeabilities than sorbing gases like methane. Permeability coefficients measured with successively increasing mean gas pressures were consistently lower than those determined at decreasing mean gas pressures. This permeability hysteresis is in accordance with results reported by Harpalani and McPherson (1985). The kinetics of matrix transport processes were studied by sorption tests on different particle sizes at various moisture contents and temperatures (cf. Busch et al., 2006). Methane uptake rates were determined from the pressure decline curves recorded for each particle-size fraction, and "diffusion coefficients" were calculated using several unipore and bidisperse diffusion models. While the CH4 sorption capacity of moisture-equilibrated coals was significantly lower (by 50%) than of dry coals, no hysteresis was observed between sorption and desorption on dry and moisture-equilibrated samples and the sorption isotherms recorded for different particle sizes were essentially identical. The CH4 uptake rates were lower by a factor of two for moist coals than for dry coals. Busch, A., Gensterblum, Y., Krooss, B.M. and Siemons, N., 2006. Investigation of high-pressure selective adsorption/desorption behaviour of CO2 and CH4 on coals: An experimental study. International Journal of Coal Geology, 66(1-2): 53-68. Harpalani, S. and McPherson, M.J., 1985. Effect of stress on permeability of coal. Quarterly Review of methane from coal seams technology, 3(2): 23-29. Seidle, J.P., Jeansonne, M.W. and Erickson, D.J., 1992. Application of Matchstick Geometry to Stress-Dependent Permeability in Coals, SPE Rocky Mountain Regional Meeting, Casper, Wyoming.

  15. CO2-ECBM related coupled physical and mechanical transport processes

    NASA Astrophysics Data System (ADS)

    Gensterblum, Y.; Sartorius, M.; Busch, A.; Cumming, D.; Krooss, B. M.

    2012-04-01

    The interrelation of cleat transport processes and mechanical properties was investigated by permeability tests at different stress levels (60% to 130% of in-situ stress) with sorbing (CH4, CO2) and inert gases (N2, Ar, He) on a sub bituminous A coal from the Surat Basin, Queensland Australia. From the flow tests under controlled triaxial stress conditions the Klinkenberg-corrected "true" permeability coefficients and the Klinkenberg slip factors were derived. The "true"-, absolute or Klinkenberg corrected permeability shows a gas type dependence. Following the approach of Seidle et al. (1992) the cleat volume compressibility (cf) was calculated from observed changes in apparent permeability upon variation of external stress (at equal mean gas pressures). The observed effects also show a clear dependence on gas type. Due to pore or cleat compressibility the cleat aperture decreases with increasing effective stress. Vice versa we observe with increasing mean pressure at lower confining pressure an increase in permeability which we attribute to a cleat aperture widening. The cleat volume compressibility (cf) also shows a dependence on the mean pore pressure. Non-sorbing gases like helium and argon show higher apparent permeabilities than sorbing gases like methane. Permeability coefficients measured with successively increasing mean gas pressures were consistently lower than those determined at decreasing mean gas pressures. This permeability hysteresis is in accordance with results reported by Harpalani and McPherson (1985). The kinetics of matrix transport processes were studied by sorption tests on different particle sizes at various moisture contents and temperatures (cf. Busch et al., 2006). Methane uptake rates were determined from the pressure decline curves recorded for each particle-size fraction, and "diffusion coefficients" were calculated using several unipore and bidisperse diffusion models. While the CH4 sorption capacity of moisture-equilibrated coals was significantly lower (by 50%) than of dry coals, no hysteresis was observed between sorption and desorption on dry and moisture-equilibrated samples and the sorption isotherms recorded for different particle sizes were essentially identical. The CH4 uptake rates were lower by a factor of two for moist coals than for dry coals. Busch, A., Gensterblum, Y., Krooss, B.M. and Siemons, N., 2006. Investigation of high-pressure selective adsorption/desorption behaviour of CO2 and CH4 on coals: An experimental study. International Journal of Coal Geology, 66(1-2): 53-68. Harpalani, S. and McPherson, M.J., 1985. Effect of stress on permeability of coal. Quarterly Review of methane from coal seams technology, 3(2): 23-29. Seidle, J.P., Jeansonne, M.W. and Erickson, D.J., 1992. Application of Matchstick Geometry to Stress-Dependent Permeability in Coals, SPE Rocky Mountain Regional Meeting, Casper, Wyoming.

  16. Physical Processes in the Vicinity of a Supermassive Black Hole

    NASA Astrophysics Data System (ADS)

    Do, Tuan

    2010-08-01

    The Galactic center offers us an opportunity to study the environment around a supermassive black hole at a level of detail not possible in other galactic nuclei. This potential has been greatly expanded by the implementation of laser guide star adaptive optics and integral field spectroscopy on large ground-based telescopes. This thesis takes advantage of these technologies to address the nature of the variable near-infrared emission from the black hole as well as test theories of the equilibrium configuration of a star cluster with a supermassive black hole at its center. First, we present the results of near-infrared (2 and 3 micron) monitoring of Sgr A*-IR with 1 min time sampling. Sgr A*-IR was observed continuously for up to three hours on each of seven nights, between 2005 July and 2007 August. Sgr A*-IR is detectable at all times and is continuously variable, with a median observed 2 micron flux density of 0.192 mJy, corresponding to 16.3 magnitude at K^'. These observations allow us to investigate Nyquist sampled periods ranging from about 2 minutes to an hour. Using Monte Carlo simulations, we find that the variability of Sgr A* in this data set is consistent with models based on correlated noise with power spectra having frequency dependent power law slopes between 2.0 to 3.0, consistent with those reported for AGN light curves. Of particular interest are periods of 20 min, corresponding to a quasi-periodic signal claimed based upon previous near-infrared observations and interpreted as the orbit of a `hot spot' at or near the last stable orbit of a spinning black hole. We find no significant periodicity at any time scale probed in these new observations for periodic signals. This study is sensitive to periodic signals with amplitudes greater than 20% of the maximum amplitude of the underlying red noise component for light curves with duration greater than 2 hours at a 98% confidence limit. Second, we report on the structure of the nuclear star cluster in the innermost 0.16 pc of the Galaxy as measured by the number density profile of late-type giants. Using laser guide star adaptive optics in conjunction with the integral field spectrograph, OSIRIS, at the Keck II telescope, we are able to differentiate between the older, late-type ( 1 Gyr) stars, which are presumed to be dynamically relaxed, and the unrelaxed young ( 6 Myr) population. This distinction is crucial for testing models of stellar cusp formation in the vicinity of a black hole, as the models assume that the cusp stars are in dynamical equilibrium in the black hole potential. In the survey region, we classified 77 stars as early-type 79 stars as late-type. We find that contamination from young stars is significant, with more than twice as many young stars as old stars in our sensitivity range (K' < 15.5) within the central arcsecond. Based on the late-type stars alone, the surface stellar number density profile, ?(R) ? R(-?) , is flat, with ? = -0.260.24. Monte Carlo simulations of the possible de-projected volume density profile, n(r) ? r^{-?}, show that ? is less than 1.0 at the 99.7 % confidence level. These results are consistent with the nuclear star cluster having no cusp, with a core profile that is significantly flatter than predicted by most cusp formation theories, and even allows for the presence of a central hole in the stellar distribution. Of the possible dynamical interactions that can lead to the depletion of the red giants observable in this survey - stellar collisions, mass segregation from stellar remnants, or a recent merger event - mass segregation is the only one that can be ruled out as the dominant depletion mechanism. The degeneracy in the true distribution of stars cannot be broken with number counts alone, but we show how the addition of kinematic measurements can remov! e the degeneracy. Resolving the physical origin of the lack of a stellar cusp will have important implications for black hole growth models and inferences on the presence of a black hole based upon stellar distributions.

  17. Applications of the First Law to Ecological Systems. Physical Processes in Terrestrial and Aquatic Ecosystems, Thermodynamics.

    ERIC Educational Resources Information Center

    Stevenson, R. D.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This report describes concepts presented in another module called "The First Law of

  18. The First Law of Thermodynamics for Ecosystems. Physical Processes in Terrestrial and Aquatic Ecosystems, Thermodynamics.

    ERIC Educational Resources Information Center

    Stevenson, R. D.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module and a comparison module are concerned with elementary concepts of thermodynamics as…

  19. Programmer's Guide for FFORM. Physical Processes in Terrestrial and Aquatic Ecosystems, Computer Programs and Graphics Capabilities.

    ERIC Educational Resources Information Center

    Anderson, Lougenia; Gales, Larry

    This module is part of a series designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. FFORM is a portable format-free input subroutine package written in ANSI Fortran IV

  20. Physical and chemical controls on the critical zone

    USGS Publications Warehouse

    Anderson, S.P.; Von Blanckenburg, F.; White, A.F.

    2007-01-01

    Geochemists have long recognized a correlation between rates of physical denudation and chemical weathering. What underlies this correlation? The Critical Zone can be considered as a feed-through reactor. Downward advance of the weathering front brings unweathered rock into the reactor. Fluids are supplied through precipitation. The reactor is stirred at the top by biological and physical processes. The balance between advance of the weathering front by mechanical and chemical processes and mass loss by denudation fixes the thickness of the Critical Zone reactor. The internal structure of this reactor is controlled by physical processes that create surface area, determine flow paths, and set the residence time of material in the Critical Zone. All of these impact chemical weathering flux.

  1. Process monitoring using automatic physical measurement based on electrical and physical variability analysis

    NASA Astrophysics Data System (ADS)

    Shauly, Eitan N.; Levi, Shimon; Schwarzband, Ishai; Adan, Ofer; Latinsky, Sergey

    2015-04-01

    A fully automated silicon-based methodology for systematic analysis of electrical features is shown. The system was developed for process monitoring and electrical variability reduction. A mapping step was created by dedicated structures such as static-random-access-memory (SRAM) array or standard cell library, or by using a simple design rule checking run-set. The resulting database was then used as an input for choosing locations for critical dimension scanning electron microscope images and for specific layout parameter extraction then was input to SPICE compact modeling simulation. Based on the experimental data, we identified two items that must be checked and monitored using the method described here: transistor's sensitivity to the distance between the poly end cap and edge of active area (AA) due to AA rounding, and SRAM leakage due to a too close N-well to P-well. Based on this example, for process monitoring and variability analyses, we extensively used this method to analyze transistor gates having different shapes. In addition, analysis for a large area of high density standard cell library was done. Another set of monitoring focused on a high density SRAM array is also presented. These examples provided information on the poly and AA layers, using transistor parameters such as leakage current and drive current. We successfully define "robust" and "less-robust" transistor configurations included in the library and identified unsymmetrical transistors in the SRAM bit-cells. These data were compared to data extracted from the same devices at the end of the line. Another set of analyses was done to samples after Cu M1 etch. Process monitoring information on M1 enclosed contact was extracted based on contact resistance as a feedback. Guidelines for the optimal M1 space for different layout configurations were also extracted. All these data showed the successful in-field implementation of our methodology as a useful process monitoring method.

  2. Dissolution of Olivine, Siderite, and Basalt at 80 Deg C in 0.1 M H2SO4 in a Flow Through Process: Insights into Acidic Weathering on Mars

    NASA Technical Reports Server (NTRS)

    Golden, D. C.; Ming, D. W.; Hausrath, E. M.; Morris, R. V.; Niles, P. B.; Achilles, C. N.; Ross, D. K.; Cooper, B. L.; Gonzalex, C. P.; Mertzman, S. A.

    2012-01-01

    The occurrence of jarosite, other sulfates (e.g., Mg-and Ca-sulfates), and hematite along with silicic-lastic materials in outcrops of sedimentary materials at Meridiani Planum (MP) and detection of silica rich deposits in Gusev crater, Mars, are strong indicators of local acidic aqueous processes [1,2,3,4,5]. The formation of sediments at Meridiani Planum may have involved the evaporation of fluids derived from acid weathering of Martian basalts and subsequent diagenesis [6,7]. Also, our previous work on acid weathering of basaltic materials in a closed hydro-thermal system was focused on the mineralogy of the acid weathering products including the formation of jarosite and gray hematite spherules [8,9,10]. The object of this re-search is to extend our earlier qualitative work on acidic weathering of rocks to determine acidic dissolution rates of Mars analog basaltic materials at 80 C using a flow-thru reactor. We also characterized residual phases, including poorly crystalline or amorphous phases and precipitates, that remained after the treatments of olivine, siderite, and basalt which represent likely MP source rocks. This study is a stepping stone for a future simulation of the formation of MP rocks under a range of T and P.

  3. A Model for Formation of Dust, Soil and Rock Coatings on Mars: Physical and Chemical Processes on the Martian Surface

    NASA Technical Reports Server (NTRS)

    Bishop, Janice; Murchie, Scott L.; Pieters, Carle M.; Zent, Aaron P.

    2001-01-01

    This model is one of many possible scenarios to explain the generation of the current surface material on Mars using chemical, magnetic and spectroscopic data From Mars and geologic analogs from terrestrial sites. One basic premise of this model is that the dust/soil units are not derived exclusively from local rocks, but are rather a product of global, and possibly remote, weathering processes. Another assumption in this model is that there are physical and chemical interactions of the atmospheric dust particles and that these two processes create distinctly different results on the surface. Physical processes distribute dust particles on rocks and drift units, forming physically-aggregated layers; these are reversible processes. Chemical reactions of the dust/soil particles create alteration rinds on rock surfaces and cohesive, crusted surface units between rocks, both of which are relatively permanent materials. According to this model the dominant components of the dust/soil particles are derived from alteration of volcanic ash and tephra, and contain primarily nanophase and poorly crystalline ferric oxides/oxyhydroxide phases as well as silicates. These phases are the alteration products that formed in a low moisture environment. These dust/soil particles also contain a smaller amount of material that was exposed to more water and contains crystalline ferric oxides/oxyhydroxides, sulfates and clay silicates. These components could have formed through hydrothermal alteration at steam vents or fumeroles, thermal fluids, or through evaporite deposits. Wet/dry cycling experiments are presented here on mixtures containing poorly crystalline and crystalline ferric oxides/oxyhydroxides, sulfates and silicates that range in size from nanophase to 1-2 pm diameter particles. Cemented products of these soil mixtures are formed in these experiments and variation in the surface texture was observed for samples containing smectites, non-hydrated silicates or sulfates. Reflectance spectra were measured of the initial particulate mixtures, the cemented products and ground versions of the cemented material. The spectral contrast in the visible/near-infrared and mid-infrared regions is significantly reduced for the cemented material compared to the initial soil, and somewhat reduced for the ground, cemented soil compared to the initial soil. The results of this study suggest that diurnal and seasonal cycling on Mars will have a profound effect on the texture and spectral properties of the dust/soil particles on the surface. The model developed in this study provides an explanation for the generation of cemented or crusted soil units and rock coatings on Mars and may explain albedo variations on the surface observed near large rocks or crater rims.

  4. Space Weathering in the Mercurian Environment

    NASA Technical Reports Server (NTRS)

    Noble, S. K.; Pieters, C. M.

    2001-01-01

    Space weathering processes are known to be important on the Moon. These processes both create the lunar regolith and alter its optical properties. Like the Moon, Mercury has no atmosphere to protect it from the harsh space environment and therefore it is expected that it will also incur the effects of space weathering. However, there are many important differences between the environments of Mercury and the Moon. These environmental differences will almost certainly affect the weathering processes and the products of those processes. It should be possible to observe the effects of these differences in Vis (visible)/NIR (near infrared) spectra of the type expected to be returned by MESSENGER. More importantly, understanding these weathering processes and their consequences is essential for evaluating the spectral data returned from MESSENGER and other missions in order to determine the mineralogy and the Fe content of the Mercurian surface. Additional information is contained in the original extended abstract.

  5. The Kinetics and Thermodynamics of the Phenol from Cumene Process: A Physical Chemistry Experiment.

    ERIC Educational Resources Information Center

    Chen, Edward C. M.; Sjoberg, Stephen L.

    1980-01-01

    Presents a physical chemistry experiment demonstrating the differences between thermodynamics and kinetics. The experiment used the formation of phenol and acetone from cumene hydroperoxide, also providing an example of an industrially significant process. (CS)

  6. The International Space Weather Initiative

    NASA Astrophysics Data System (ADS)

    Davila, Joseph; Gopalswamy, Nat

    The International Space Weather Initiative (ISWI) is an international program of scientific collaboration to understand the external drivers of space weather. One of the major thrusts of the ISWI is to deploy arrays of small instruments such as magnetometers, radio antennas, GPS receivers, all-sky cameras, particle detectors, etc. around the world to provide global measurements of heliospheric phenomena. Scientists from approximately 70 countries now participate in the instrument operation, data collection, analysis, and publication of scientific results, working at the forefront of science research. The purpose of the ISWI is to continue the scientific study of universal processes in the solar system that affect space weather and the terrestrial environment, and to continue to coordinate the deployment and operation of new and existing instrument arrays aimed at understanding the impacts of Space Weather on Earth and the near-Earth environment. This project provides an excellent opportunity for potential instrument providers to engage collaborators from specific geographical locations, and to broaden the coverage of existing instrument arrays. By deploying instruments in strategically chosen locations new science and a more global view of heliophysical processes is obtained. These data will also provide new inputs for global ionospheric models in the future.

  7. Weather and climate

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Recommendations for using space observations of weather and climate to aid in solving earth based problems are given. Special attention was given to: (1) extending useful forecasting capability of space systems, (2) reducing social, economic, and human losses caused by weather, (3) development of space system capability to manage and control air pollutant concentrations, and (4) establish mechanisms for the national examination of deliberate and inadvertent means for modifying weather and climate.

  8. Black rings and the physical process version of the first law of thermodynamics

    SciTech Connect

    Rogatko, Marek

    2005-10-01

    We consider the problem of the physical process version of the first law of black ring thermodynamics in n-dimensional Einstein gravity with additional (p+1)-form field strength and dilaton fields. The first order variations of mass, angular momentum and local charge for black ring are derived. From them we prove the physical process version of the first law of thermodynamic for stationary black rings.

  9. Analysis of physical-chemical processes governing SSME internal fluid flows

    NASA Technical Reports Server (NTRS)

    Singhal, A. K.; Owens, S. F.; Mukerjee, T.; Prakash, C.; Przekwas, A. J.; Kannapel, M.

    1985-01-01

    The basic issues concerning the physical chemical processes of the Space Shuttle Main Engine are discussed. The objectives being to supply the general purpose CFD code PHOENICS and the associated interactive graphics package - GRAFFIC; to demonstrate code usage on SSME related problems; to perform computations and analyses of problems relevant to current and future SSME's; and to participate in the development of new physical models of various processes present in SSME components. These objectives are discussed in detail.

  10. Weather assessment and forecasting

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Data management program activities centered around the analyses of selected far-term Office of Applications (OA) objectives, with the intent of determining if significant data-related problems would be encountered and if so what alternative solutions would be possible. Three far-term (1985 and beyond) OA objectives selected for analyses as having potential significant data problems were large-scale weather forecasting, local weather and severe storms forecasting, and global marine weather forecasting. An overview of general weather forecasting activities and their implications upon the ground based data system is provided. Selected topics were specifically oriented to the use of satellites.

  11. Pilot Weather Advisor System

    NASA Technical Reports Server (NTRS)

    Lindamood, Glenn; Martzaklis, Konstantinos Gus; Hoffler, Keith; Hill, Damon; Mehrotra, Sudhir C.; White, E. Richard; Fisher, Bruce D.; Crabill, Norman L.; Tucholski, Allen D.

    2006-01-01

    The Pilot Weather Advisor (PWA) system is an automated satellite radio-broadcasting system that provides nearly real-time weather data to pilots of aircraft in flight anywhere in the continental United States. The system was designed to enhance safety in two distinct ways: First, the automated receipt of information would relieve the pilot of the time-consuming and distracting task of obtaining weather information via voice communication with ground stations. Second, the presentation of the information would be centered around a map format, thereby making the spatial and temporal relationships in the surrounding weather situation much easier to understand

  12. Summary of the NASA/MSFC FY-79 Severe Storm and Local Weather research review. [cloud physics, atmospheric electricity, and mesoscale/storm dynamics reserach

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Significant acomplishments, current focus of work, plans for FY-80, and recommendations for new research are outlined for 36 research projects proposed for technical monitoring by the Atmospheric Sciences Division at Marshall Space Flight Center. Topics of the investigations, which were reviewed at a two-day meeting, relate to cloud physics, atmospheric electricity, and mesoscale/storm dynamics.

  13. Introduction of a pyramid guiding process for general musculoskeletal physical rehabilitation.

    PubMed

    Stark, Timothy W

    2006-01-01

    Successful instruction of a complicated subject as Physical Rehabilitation demands organization. To understand principles and processes of such a field demands a hierarchy of steps to achieve the intended outcome. This paper is intended to be an introduction to a proposed pyramid scheme of general physical rehabilitation principles. The purpose of the pyramid scheme is to allow for a greater understanding for the student and patient. As the respected Food Guide Pyramid accomplishes, the student will further appreciate and apply supported physical rehabilitation principles and the patient will understand that there is a progressive method to their functional healing process. PMID:16759396

  14. Weather and emotional state

    NASA Astrophysics Data System (ADS)

    Spasova, Z.

    2010-09-01

    Introduction Given the proven effects of weather on the human organism, an attempt to examine its effects on a psychic and emotional level has been made. Emotions affect the bio-tonus, working ability and concentration, hence their significance in various domains of economic life, such as health care, education, transportation, tourism, etc. Data and methods The research has been made in Sofia City within a period of 8 months, using 5 psychological methods (Eysenck Personality Questionnaire (EPQ), State-Trait Anxiety Inventory (STAI), Test for Self-assessment of the emotional state (developed by Wessman and Ricks), Test for evaluation of moods and Test "Self-confidence - Activity - Mood" (developed by the specialists from the Military Academy in Saint Petersburg). The Fiodorov-Chubukov's complex-climatic method was used to characterize meteorological conditions because of the purpose to include in the analysis a maximal number of meteorological elements. 16 weather types are defined in dependence of the meteorological elements values according to this method. Abrupt weather changes from one day to another, defined by the same method, were considered as well. Results and discussions The results obtained by t-test show that the different categories of weather lead to changes in the emotional status, which indicates a character either positive or negative for the organism. The abrupt weather changes, according to expectations, have negative effect on human emotions but only when a transition to the cloudy weather or weather type, classified as "unfavourable" has been realized. The relationship between weather and human emotions is rather complicated since it depends on individual characteristics of people. One of these individual psychological characteristics, marked by the dimension "neuroticism", has a strong effect on emotional reactions in different weather conditions. Emotionally stable individuals are more "protected" to the weather influence on their emotions, while those who are emotionally unstable have a stronger dependence to the impacts of the weather.

  15. Spatial patterns and controls of soil chemical weathering rates along a transient hillslope

    USGS Publications Warehouse

    Yoo, K.; Mudd, S.M.; Sanderman, J.; Amundson, Ronald; Blum, A.

    2009-01-01

    Hillslopes have been intensively studied by both geomorphologists and soil scientists. Whereas geomorphologists have focused on the physical soil production and transport on hillslopes, soil scientists have been concerned with the topographic variation of soil geochemical properties. We combined these differing approaches and quantified soil chemical weathering rates along a grass covered hillslope in Coastal California. The hillslope is comprised of both erosional and depositional sections. In the upper eroding section, soil production is balanced by physical erosion and chemical weathering. The hillslope then transitions to a depositional slope where soil accumulates due to a historical reduction of channel incision at the hillslope's base. Measurements of hillslope morphology and soil thickness were combined with the elemental composition of the soil and saprolite, and interpreted through a process-based model that accounts for both chemical weathering and sediment transport. Chemical weathering of the minerals as they moved downslope via sediment transport imparted spatial variation in the geochemical properties of the soil. Inverse modeling of the field and laboratory data revealed that the long-term soil chemical weathering rates peak at 5 g m- 2 yr- 1 at the downslope end of the eroding section and decrease to 1.5 g m- 2 yr- 1 within the depositional section. In the eroding section, soil chemical weathering rates appear to be primarily controlled by the rate of mineral supply via colluvial input from upslope. In the depositional slope, geochemical equilibrium between soil water and minerals appeared to limit the chemical weathering rate. Soil chemical weathering was responsible for removing 6% of the soil production in the eroding section and 5% of colluvial influx in the depositional slope. These were among the lowest weathering rates reported for actively eroding watersheds, which was attributed to the parent material with low amount of weatherable minerals and intense coating of the primary minerals by secondary clay and iron oxides. We showed that both the morphologic disequilibrium of the hillslope and the spatial heterogeneity of soil properties are due to spatial variations in the physical and chemical processes that removed mass from the soil. ?? 2009 Elsevier B.V.

  16. Integrating Physical and Chemical Alteration Mechanisms of Soil Formation on Mars from the Mars Exploration Rovers

    NASA Astrophysics Data System (ADS)

    McGlynn, I. O.; McSween, H. Y.; Fedo, C. M.

    2011-03-01

    Models of soil formation by chemical weathering must also incorporate physical processes including impact gardening and aeolian transport to remove and concentrate olivine and explain the compositional scatter of soils along the olivine-feldspar join.

  17. PREFACE: First International Workshop on Nonequilibrium Processes in Plasma Physics and Studies of Environment

    NASA Astrophysics Data System (ADS)

    Petrović, Z. Lj; Malović, G.; Tasić, M.; Nikitović, Ž.

    2007-06-01

    This volume is a collection of papers associated with a series of invited lectures presented at the First Workshop on Nonequilibrium processes in Plasma Physics and studies of Environment that was held at Mt Kopaonik in August 2006. The workshop originated as a part of the FP6 COE 026328 which had the basic aim of promoting centers of excellence in Western Balkan countries, to facilitate dissemination of their results and to help them establish themselves in the broader arena of European and international science. So the best way to achieve all those goals was to prepare a workshop associated with the local conference SPIG (Symposium on Physics of Ionized Gases) where the participants could attend sessions in which the host Laboratory presented progress reports and papers and thereby gain a full perspective of our results. At the same time this allowed participants in the COE the opportunity to compare their results with the results of external speakers and to gain new perspectives and knowledge. The program of the workshop was augmented by inviting some of our colleagues who visited the COE in recent years or have an active collaboration with a participating member. In that respect this volume is not only a proceedings of the workshop but a collection of papers related to the topic of the workshop: Non-equilibrium phenomena in plasmas and in the science of our environment. The idea is to offer review articles either summarizing a broader area of published or about to be published work or to give overviews showing preliminary results of the works in progress. The refereeing of the papers consisted of two parts, first in selection of the invitees and second in checking the submitted manuscripts. The papers were refereed to the standard of the Journal. As the program of the COE covers a wide area of topics from application of plasmas in nano- electronics to monitoring and removal of pollutants in the atmosphere, so the program of the workshop covered an even broader range of topics with the common thread of non- equilibrium phenomena playing a major part in the basic physics and also in the technological applications. The universal symbol of non-equilibrium phenomena is Maxwell's demon and it was selected, as designed by Professor Rastko Ćirić (of Belgrade's University for Fine Arts), to be the symbol of the conference. In plasma physics, the field is usually divided between equilibrium and non-equilibrium plasmas. The advantage of studying plasmas in thermal equilibrium is that they may be described by universal laws, such as Saha and Boltzmann equations. The only problem is that, apart from the very early stages in the development of the universe, such plasmas do not exist, although there are plasmas that come very close and at least satisfy the thermal laws locally. Non-equilibrium plasmas have laws unique to each situation and studies of their idiosyncrasies continue to provide a lot of food for thought for scientists, possibilities for applications and job opportunities. Or as Tolstoy wrote, `Happy families are all alike; every unhappy family is unhappy in its own way?'. So, while making analogy of the non-equilibrium with the lack of happiness may sound discouraging, the scientists who try to observe these phenomena (like psychologists in the case of families) have plenty to study and are, therefore, likely to be happy. At the same time non-equilibrium phenomena in plasmas and in the atmosphere are extremely important. A fact we should be aware of every time we use an integrated circuit manufactured after the late 1970s or whenever weather changes, wind blows and pollution is carried in from some distant locations. This volume starts with a paper by D Batani (Milano, Italy) on shock waves, an example of plasmas that may be locally thermal but display very strong gradients, M Pinheiro (Lisboa, Portugal) contributed an article on anomalous diffusion in magnetized plasmas, a problem that has been addressed in the literature from many different standpoints. A special case of non-equilibrium is that of non-neutral plasmas, i.e. plasmas devoid of ions, as described in the lecture and paper by J Marler (Appleton, USA). Physics of swarms (the low space charge limit of ionized gases) is similar to the previous study in the fact that we may have only one group of charged particles electrons (or ions). But the difference is that the latter has a much higher pressure and therefore number of collisions. In the lecture on one aspect of the application of swarm data (transport coefficients) to determine the electron scattering cross sections R White (Townsville, Australia) addresses a long standing controversy in the vibrational excitation of H2 of an unacceptable discrepancy between swarm results and binary collision experiments and theories, (a problem that has been of particular importance to the host Laboratory). The lecture of N Dyatko (Troitsk, Russian Federation) tackles one of the most interesting recent problems in the transport theory of ionized gases, that of the negative absolute conductivity and attempts to translate it to solid state physics where the stakes are much higher. The swarm studies were always based on excellent experimental data and the leading experimental group today is that of J de Urquijo (Cuernavaca, Mexico) who presents a review of a wide range of transport data that his group obtained in fluorinated gases. The gas breakdown in dc and high frequency fields was addressed by M Radmilović-Rađenović (Belgrade, Serbia) by applying a detailed secondary electron production model in Particle in Cell (PIC) code and comparing the results to a broad range of experimental data. The hybrid (fluid-Monte Carlo) model has been applied in the study by Z Donko and K Kutasi (Budapest, Hungary) of low pressure obstructed glow discharges to decribe the effect of fast neutrals on gas discharges. A study of kinetics of negative ions of hydrogen in glow discharges with positive column and in hollow cathode dicharges is presented by R Djulgerova (Sofia, Boulgaria). Modelling and experimental results for surface plasmas with an aim to study the kinetics of dissociation are given by V Guerra (Lisboa, Portugal). L Campbell (Adelaide, Australia) describes modelling of a similar kinetics, albeit for a significantly larger ionized gas in his study of electron induced processes in the upper atmosphere. Atmospheric pressure discharges is also the topic of the work of T Gans (Belfast, Northern Ireland andBochum, Germany) but his experiments with atmospheric plasma jet are carried out at sea level and therefore the pressures are significantly higher than those for usual non-equilibrium plasmas. Higher still are the densities in plasmas generated in liquids (for medical purposes) as described in the paper of W Graham (Belfast, Northern Ireland). Another very applied aspect of non-equilibrium plasma is highlighted in a comprehensive review given by S Radovanov (Gloucester, USA) of the basic physics of the non-equilibrium plasma source for implantation of boron (for doping in the manufacture of integrated circuits) . A topical review of diagnostics of dusty particles in rf plasmas is given by I Stefanović, J Winter and colleagues (Bochum, Germany) and includes implications for plasma processing, nanotechnologies and all the way to astrophysics. Transport of particles of similar sizes in the atmosphere and its influence on the pollution of the human environment is presented in the paper by M Tasić (Belgrade, Serbia). Finally a paper that connects both aspects of the workshop, plasma physics and environment, is the review of M Radetić (Belgrade, Serbia) which covers application of low pressure non-equilibrium plasmas in treatment of textiles, not only to reduce the cost and environmental impact of the technology but also to produce filters to purify waters used in the process and in general. The broad range of topics indicates that modern plasma physics is driven not only by the need to further understand the fundamental principles but with an eye towards applications. Consequently in addition to furthering the cause of physics, we strive to improve increasingly complex technologies or develop new technologies. The non-equilibrium nature of plasmas that are the subject of our studies allows us to control properties that are critical and to design optimum conditions for these varied applications. We hope that this volume will serve as a useful source of information for experienced researchers, as a textbook for postgraduate students and as a reminder, for all who attended the workshop, of the wonderful time (http://www.euj07.phy.bg.ac.yu/index.php?page=p04) we had on top of the mountain Kopaonik, even though we were subjected to freezing temperatures in the middle of summer. Organization of this workshop was supported by INCO EU FP6 026328 project (Reinforcing Experimental Center for Non-equilibrium studies with Application in Nano-technologies, Etching of Integrated Circuits and Environmental Research), by the Ministry of Science and Environment of Serbia (project 141025) and also, to a great extend, by the individual funding of the participants some of whom traveled from remote continents in order to participate. Z Lj Petrović, G Malović, M Tasić and Ž Nikitović Editors

  18. Alternative Processes for Water Reclamation and Solid Waste Processing in a Physical/chemical Bioregenerative Life Support System

    NASA Technical Reports Server (NTRS)

    Rogers, Tom D.

    1990-01-01

    Viewgraphs on alternative processes for water reclamation and solid waste processing in a physical/chemical-bioregenerative life support system are presented. The main objective is to focus attention on emerging influences of secondary factors (i.e., waste composition, type and level of chemical contaminants, and effects of microorganisms, primarily bacteria) and to constructively address these issues by discussing approaches which attack them in a direct manner.

  19. Basalt weathering in an Arctic Mars-analog site

    NASA Astrophysics Data System (ADS)

    Yesavage, Tiffany; Thompson, Aaron; Hausrath, Elisabeth M.; Brantley, Susan L.

    2015-07-01

    The martian surface has undergone chemical and physical weathering in the past, and these processes may continue intermittently today. To explore whether martian rocks are likely to retain features indicative of weathering, we investigated how basaltic material weathers on Earth. Specifically, we investigated weathering of a Quaternary-aged basaltic flow at the Sverrefjell volcano in Svalbard, above the Arctic Circle. This flow weathered since deglaciation under cold, dry (<400 mm/yr) conditions. We analyzed a ?75-cm core of regolith for chemical loss and then characterized the mineralogical and morphological properties using electron microscopy (EM), X-ray diffraction (XRD), infrared (IR) spectroscopy and selective chemical dissolution. In addition, we ran colloidal dispersion, wetting/drying, and freeze/thaw experiments. In the regolith, we observed concentrations of short-range ordered (SRO) phases similar to those observed in warmer, wetter volcanic ash soils. IR and EM analyses of the clay-sized fraction were consistent with allophane as the predominant secondary phase. Selective chemical extractions targeting SRO phases indicated lower Al/Si ratios than those observed in volcanic soils reported in warmer localities, which we attribute to Si-rich allophane and/or abundant Si-rich rock coatings. The oxic circumneutral-pH colloidal dispersion experiments mobilized Al, Fe and Ti primarily as 260-415 nm particles and Ca, Mg and Na as solutes. Si was lost both in the colloidal and dissolved forms. Dispersed colloids likely contain allophane and ferrihydrite. Under anoxic conditions, dissolution of Fe oxide cements also released fines. The experiments help to explain elemental loss from the clay-sized regolith fraction at Svalbard: observed depletions in Ca, K, Mg and Na were likely due to solute loss, while particle-reactive Al, Fe, Si and Ti were mostly retained. Wetting/drying was observed to be as effective as freeze/thaw in driving material loss. It is thus possible that cyclic adsorption of water onto basaltic rocks in this dry climate may result in high physical spalling rates that in turn promote chemical leaching. Many observations at Sverrefjell are similar to inferences from Mars: the presence of SRO phases, Si-rich coatings, and/or Si-rich allophane, as well as the persistence of olivine. Given these similarities, it is inferred that Sverrefjell volcano is a good analog for martian weathering and that other processes operating at Sverrefjell may also have occurred on Mars, including Na leaching, surface spalling, and precipitation of Si-rich layers. Such processes could have occurred on Mars wherever basalts were exposed to water at circumneutral pH for thousands to tens of thousands of years.

  20. Tracking Weather Satellites.

    ERIC Educational Resources Information Center

    Martin, Helen E.

    1996-01-01

    Describes the use of weather satellites in providing an exciting, cohesive framework for students learning Earth and space science and in providing a hands-on approach to technology in the classroom. Discusses the history of weather satellites and classroom satellite tracking. (JRH)

  1. Weather and Culture.

    ERIC Educational Resources Information Center

    Contemporary Learning Center, Houston, TX.

    This document is a minicourse on the interaction of weather, environment, and culture. It is designed for the high school student to read and self-administer. Performance objectives, enabling activities, and postassessment questions are given for each of eight modules. The modules are: (1) Basic Facts About Your Weather Known As Rain, (2) The

  2. The Home Weather Station.

    ERIC Educational Resources Information Center

    Steinke, Steven D.

    1991-01-01

    Described is how an amateur weather observer measures and records temperature and precipitation at a well-equipped, backyard weather station. Directions for building an instrument shelter and a description of the instruments needed for measuring temperature and precipitation are included. (KR)

  3. Weather Fundamentals: Clouds. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) discusses how clouds form, the different types of clouds, and the important role they play in

  4. Mild and Wild Weather.

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Presents background information and six activities that focus on clouds, precipitation, and stormy weather. Each activity includes an objective, recommended age level(s), subject area(s), and instructional strategies. Also provided are two ready-to-copy pages (a coloring page on lightning and a list of weather riddles to solve). (JN)

  5. Teacher's Weather Sourcebook.

    ERIC Educational Resources Information Center

    Konvicka, Tom

    This book is a teaching resource for the study of weather-related phenomena. A "weather unit" is often incorporated into school study because of its importance to our daily lives and because of its potential to cut across disciplinary content. This book consists of two parts. Part I covers the major topics of atmospheric science such as the modern

  6. Designing a Weather Station

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    The collection and analysis of weather data is crucial to the location of alternate energy systems like solar and wind. This article presents a design challenge that gives students a chance to design a weather station to collect data in advance of a large wind turbine installation. Data analysis is a crucial part of any science or engineering

  7. Weather Fundamentals: Clouds. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) discusses how clouds form, the different types of clouds, and the important role they play in…

  8. Weather Fundamentals: Wind. [Videotape].

    ERIC Educational Resources Information Center

    1998

    The videos in this educational series, for grades 4-7, help students understand the science behind weather phenomena through dramatic live-action footage, vivid animated graphics, detailed weather maps, and hands-on experiments. This episode (23 minutes) describes the roles of the sun, temperature, and air pressure in creating the incredible power

  9. On Observing the Weather

    ERIC Educational Resources Information Center

    Crane, Peter

    2004-01-01

    Rain, sun, snow, sleet, wind... the weather affects everyone in some way every day, and observing weather is a terrific activity to attune children to the natural world. It is also a great way for children to practice skills in gathering and recording information and to learn how to use simple tools in a standardized fashion. What better way to

  10. Weathering Database Technology

    ERIC Educational Resources Information Center

    Snyder, Robert

    2005-01-01

    Collecting weather data is a traditional part of a meteorology unit at the middle level. However, making connections between the data and weather conditions can be a challenge. One way to make these connections clearer is to enter the data into a database. This allows students to quickly compare different fields of data and recognize which…

  11. Weather Cardboard Carpentry

    ERIC Educational Resources Information Center

    DeBruin, Jerome E.

    1977-01-01

    Included are instructions and diagrams for building weather instruments (wind vane, Celsius temperature scale, and anemometer) from simple tools and Tri-Wall, a triple-thick corrugated cardboard. Ordering sources for Tri-Wall are listed. Additional weather instruments that can be constructed are suggested. (CS)

  12. On Observing the Weather

    ERIC Educational Resources Information Center

    Crane, Peter

    2004-01-01

    Rain, sun, snow, sleet, wind... the weather affects everyone in some way every day, and observing weather is a terrific activity to attune children to the natural world. It is also a great way for children to practice skills in gathering and recording information and to learn how to use simple tools in a standardized fashion. What better way to…

  13. Exercising in Cold Weather

    MedlinePLUS

    ... www.nia.nih.gov/Go4Life Exercising in Cold Weather Exercise has benefits all year, even during winter. ... activities when it’s cold outside: l Check the weather forecast. If it’s very windy or cold, exercise ...

  14. Fabulous Weather Day

    ERIC Educational Resources Information Center

    Marshall, Candice; Mogil, H. Michael

    2007-01-01

    Each year, first graders at Kensington Parkwood Elementary School in Kensington, Maryland, look forward to Fabulous Weather Day. Students learn how meteorologists collect data about the weather, how they study wind, temperature, precipitation, basic types/characteristics of clouds, and how they forecast. The project helps the students grow in

  15. Aviation Weather Program (AWP)

    NASA Technical Reports Server (NTRS)

    Foote, Brant

    1993-01-01

    The Aviation Weather Program (AWP) combines additional weather observations, improved forecast technology, and more efficient distribution of information to pilots, controllers, and automated systems to improve the weather information provided to the air traffic control system, pilots, and other users of aviation weather information. Specific objectives include the needs to: improve airport and en-route capacity by accurate, high resolution, timely forecasts of changing weather conditions affecting airport and en-route operations; improve analyses and forecasts of upper-level winds for efficient flight planning and traffic management; and increase flight safety through improved aviation weather hazard forecasting (e.g. icing, turbulence, severe storms, microbursts, or strong winds). The AWP would benefit from participation in a cooperative multiscale experiment by obtaining data for: evaluation of aviation weather forecast products, analysis of four dimensional data assimilation schemes, and experimental techniques for retrieving aerosol and other visibility parameters. A multiscale experiment would also be helpful to AWP by making it possible to evaluate the added benefit of enhanced data sets collected during the experiment on those forecast and analysis products. The goals of the Coperative Multiscale Experiment (CME) are an essential step in attaining the long-term AWP objective of providing two-to-four hour location-specific forecasts of significant weather. Although the possibility of a funding role for the AWP in the CME is presently unclear, modest involvement of Federal Aviation Administration (FAA)/AWP personnel could be expected.

  16. Weatherizing a Structure.

    ERIC Educational Resources Information Center

    Metz, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with weatherizing a structure. Its objective is for the student to be able to analyze factors related to specific structures that indicate need for weatherizing activities and to determine steps to correct defects in structures that

  17. Fabulous Weather Day

    ERIC Educational Resources Information Center

    Marshall, Candice; Mogil, H. Michael

    2007-01-01

    Each year, first graders at Kensington Parkwood Elementary School in Kensington, Maryland, look forward to Fabulous Weather Day. Students learn how meteorologists collect data about the weather, how they study wind, temperature, precipitation, basic types/characteristics of clouds, and how they forecast. The project helps the students grow in…

  18. Weathering Database Technology

    ERIC Educational Resources Information Center

    Snyder, Robert

    2005-01-01

    Collecting weather data is a traditional part of a meteorology unit at the middle level. However, making connections between the data and weather conditions can be a challenge. One way to make these connections clearer is to enter the data into a database. This allows students to quickly compare different fields of data and recognize which

  19. Teacher's Weather Sourcebook.

    ERIC Educational Resources Information Center

    Konvicka, Tom

    This book is a teaching resource for the study of weather-related phenomena. A "weather unit" is often incorporated into school study because of its importance to our daily lives and because of its potential to cut across disciplinary content. This book consists of two parts. Part I covers the major topics of atmospheric science such as the modern…

  20. Designing a Weather Station

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    The collection and analysis of weather data is crucial to the location of alternate energy systems like solar and wind. This article presents a design challenge that gives students a chance to design a weather station to collect data in advance of a large wind turbine installation. Data analysis is a crucial part of any science or engineering…

  1. KSC Weather and Research

    NASA Technical Reports Server (NTRS)

    Maier, Launa; Huddleston, Lisa; Smith, Kristin

    2016-01-01

    This briefing outlines the history of Kennedy Space Center (KSC) Weather organization, past research sponsored or performed, current organization, responsibilities, and activities, the evolution of weather support, future technologies, and an update on the status of the buoys located offshore of Cape Canaveral Air Force Station and KSC.

  2. Statistics-related and reliability-physics-related failure processes in electronics devices and products

    NASA Astrophysics Data System (ADS)

    Suhir, E.

    2014-05-01

    The well known and widely used experimental reliability "passport" of a mass manufactured electronic or a photonic product — the bathtub curve — reflects the combined contribution of the statistics-related and