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2.0
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xii, 391 pages : 23 cm
Topics: Trace elements -- Metabolism -- Mathematical models -- Congresses, Trace elements in nutrition --...
2
2.0
texts
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350 p. : 27 cm
Topics: Trace elements -- Bioavailability, Trace elements in water -- Analysis, Trace elements in water --...
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3.0
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48 pages ; 24 cm
Topics: Trace analysis -- Standards, Qualitätssicherung, Spurenanalyse, Reliability and quality control,...
LONG-TERM GOALS. To gain a better understanding of the role of colloidal organic macromolecules and inorganic colloidal microparticles in the cycling, speciation and bioavailability of trace elements in coastal waters. SCIENTIFIC OBJECTIVES. 1) Concentration determination and isolation of purified fractions of natural thiols and natural acid polysaccharides for trace metal complexation and structural experiments. 2) Determination of conditional stability constants for the complexation of...
Topics: DTIC Archive, TEXAS A AND M UNIV GALVESTON DEPT OF OCEANOGRAPHY, *ESTUARIES, *ORGANIC MATERIALS,...
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243
Jan 5, 2008
01/08
by
Moore, Johnnie N; Savka, M. W. (Michael W.); Montana University System. Water Resources Center
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"Final technical report submitted to the Montana Water Resources Center ..."
Topics: Arsenic, Arsenic, Sediment transport, Sediment transport, Trace elements in water, Trace elements...
10
10.0
Dec 3, 2019
12/19
by
Lenihan, J. M. A
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xi, 157 pages : 23 cm
Topics: Trace elements -- Toxicology, Trace elements in the body, Trace Elements, Trace elements -- Health...
The anorthositic crust of the Moon is often used as the archtypical example of a primary planetary crust. The abundance and purity of anorthosite in the Apollo sample collection and remote sensing data are generally attributed to an early global magma ocean which produced widespread floating plagioclase cumulates (the ferroan anorthosites; FANs. Recent geochronology studies report evidence of young (less than 4.4 Ga) FAN ages, which suggest that either some may not be directly produced from the...
Topics: NASA Technical Reports Server (NTRS), BRECCIA, MAGMA, ANORTHOSITE, PLANETARY CRUSTS, REMOTE...
HSE and Os isotopes are used to constrain processes such as accretion, mantle evolution, crustal recycling, and core-mantle mixing, and to constrain the timing and depth of differentiation of Mars. Although showed that the HSE contents of the martian mantle could have been established by metal-silicate equilibrium in early Mars, the role of a cooling magma ocean and associated crystallization in further fractionating the HSEs is unclear. Garnet is thought to have played an important role in...
Topics: NASA Technical Reports Server (NTRS), MARS (PLANET), PLANETARY MANTLES, SIDEROPHILE ELEMENTS,...
307
307
Jan 29, 2010
01/10
by
Montana.Natural Resource Damage Program; Montana.Dept. of Fish, Wildlife, and Parks; U.S. Fish and Wildlife Service; Confederated Salish & Kootenai Tribes of the Flathead Reservation, Montana
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"This fact booklet summarizes the Draft Conceptual Restoration Plan for the Clark Fork and Blackfoot Rivers near Milltown Dam. The State of Montana, in cooperation with the U.S. Fish and Wildlife Service and Confederated Salish and Kootenai Tribes, released this plan in May 2003 for public review and input."--Cover
Topics: Hazardous waste sites, Water, Sedimentation and deposition, Mines and mineral resources, Trace...
A glow discharge source has been adapted for use with a commercial external ion source Fourier transform ion cyclotron resonance mass spectrometer. This combination shows promising analytical usefulness. Results on National Institute of Standards and Technology stainless steel standards showed that peaks due to nominally isobaric atomic isotopes can be observed with high mass resolution (m/delta m(sub 1/2) greater than or equal 290,000). Detection limits in the high parts per billion to low...
Topics: DTIC Archive, Watson, C H, FLORIDA UNIV GAINESVILLE DEPT OF CHEMISTRY, *HIGH RESOLUTION, *MASS...
A microprobe analysis technique which has the potential for quantitative measurements of surface and bulk concentration as well as depth profiles has been investigated. This technique is termed Profile Analysis using Laser Assisted Spectroscopy (PALAS) and uses one pulsed laser to desorb or vaporize a controlled volume of the sample and a second pulsed laser to induce fluorescence in the desorbed species. The intensity of the laser induced fluorescence (LIF) provides a quantitative measure of...
Topics: DTIC Archive, Freedman, A, AERODYNE RESEARCH INC BILLERICA MA, *IMPURITIES, *GALLIUM ARSENIDES,...
The Deep Convective Clouds and Chemistry (DC3) field campaign in 2012 provided a plethora of aircraft and ground-based observations (e.g., trace gases, lightning and radar) to study deep convective storms, their convective transport of trace gases, and associated lightning occurrence and production of nitrogen oxides (NOx). Based on the measurements taken of the 29-30 May 2012 Oklahoma thunderstorm, an analysis against a Weather Research and Forecasting Chemistry (WRF-Chem) model simulation of...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC COMPOSITION, CLOUD-TO-GROUND DISCHARGES,...
The AERONET (AErosol RObotic NETwork) ground-based suite of sunphotometers provides measurements of spectral aerosol optical depth (AOD), precipitable water and spectral sky radiance, which can be inverted to retrieve aerosol microphysical properties that are critical to assessments of aerosol-climate interactions. Because of data quality criteria and sampling constraints, there are significant limitations to the temporal and spatial coverage of AERONET data and their representativeness for...
Topics: NASA Technical Reports Server (NTRS), AEROSOLS, CLOUDS (METEOROLOGY), TRACE ELEMENTS, SCANNERS,...
The Stratospheric Aerosol and Gas Experiment III (SAGE III) instrument - the fifth in a series of instruments developed for monitoring vertical distribution of aerosols, ozone, and other trace gases in the Earth's stratosphere and troposphere - is currently scheduled for delivery to the International Space Station (ISS) via the SpaceX Dragon vehicle in 2016. The Instrument Adapter Module (IAM), one of many SAGE III subsystems, continuously dissipates a considerable amount of thermal energy...
Topics: NASA Technical Reports Server (NTRS), AEROSOLS, ATMOSPHERIC COMPOSITION, LESSONS LEARNED, SAGE...
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269
Feb 5, 2010
02/10
by
Montana.Natural Resource Damage Program; Montana.Dept. of Fish, Wildlife, and Parks; U.S. Fish and Wildlife Service; Confederated Salish & Kootenai Tribes of the Flathead Reservation, Montana; WestWater Consultants; River Design Group; Geum Environmental Consulting
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Includes bibliographical references
Topics: Hazardous waste sites, Water, Sedimentation and deposition, Mines and mineral resources, Trace...
Certain anorthositic rocks that are rare in the returned lunar samples have been identified among lunar meteorites. The variety of anorthosites in the Apollo collection also is more varied than is widely recognized. James eta. identified three lithologies in a composite clast o ferroan anorthosite (FAN)-suite rocks in lunar breccia 64435. They further divided all FANs into four subgroups: anorthositic ferroan (AF), mafic magnesian (MM), mafic ferroan (MF), and anorthositic sodic (AS, absent in...
Topics: NASA Technical Reports Server (NTRS), ANORTHOSITE, BRECCIA, LUNAR ROCKS, PETROGRAPHY, LITHOLOGY,...
Over four decades of measurements exist that sample the 3-D composition of reactive trace gases in the troposphere from approximately weekly ozone sondes, instrumentation on civil aircraft, and individual comprehensive aircraft field campaigns. An obstacle to using these data to evaluate coupled chemistry-climate models (CCMs)the models used to project future changes in atmospheric composition and climateis that exact space-time matching between model fields and observations cannot be done, as...
Topics: NASA Technical Reports Server (NTRS), OZONE, SONDES, REACTIVITY, ATMOSPHERIC COMPOSITION, CIVIL...
Secondary ion mass spectrometry(SIMS) is often used to monitor elemental distributions in solids and at solid interfaces. The current status of quantitative SIMS analysis in layered multimatrix samples is presented. The basics of SIMS quantification and theories describing matrix effects will be reviewed, matrix effect calibration and depth profile corrections for A1xGa1-x As multilayers will be examined, a method of extending these calibrations to the remaining IIIA-VA semiconductors will be...
Topics: DTIC Archive, Galuska,Alan A, AEROSPACE CORP EL SEGUNDO CA MATERIALS SCIENCES LAB, *SEMICONDUCTORS,...
3
3.0
May 27, 2020
05/20
by
International Symposium on Trace Elements in Man and Animals (6th : 1987 : Pacific Grove, Calif.)
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xxv, 724 pages : 26 cm
Topics: Trace elements in the body -- Congresses, Trace elements -- Physiological effect -- Congresses,...
59
59
Jan 26, 2010
01/10
by
Montana.Natural Resource Damage Program; Montana.Dept. of Fish, Wildlife, and Parks; U.S. Fish and Wildlife Service; Confederated Salish & Kootenai Tribes of the Flathead Reservation, Montana; WestWater Consultants; River Design Group; Geum Environmental Consulting
texts
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Includes bibliographical references
Topics: Hazardous waste sites, Water, Sedimentation and deposition, Mines and mineral resources, Trace...
0
0.0
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volumes : 24 cm
Topics: Trace elements -- Environmental aspects -- United States, Environmental Pollutants, Trace Elements...
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4.0
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viii, 231 p. : 24 cm
Topics: Free radicals (Chemistry) -- Physiological effect, Active oxygen, in the body, Trace elements in...
During the past two years, researchers from several institutes joined together to take part in two SCAR experiments. The SCAR-A (Sulfates, Clouds And Radiation - Atlantic) took place in the mid-Atlantic region of the United States in July, 1993. remote sensing data were acquired with the Airborne Visible Infrared Imaging Spectrometer (AVIRIS), the MODIS Airborne Simulator (MAS), and a RC-10 mapping camera from an ER-2 aircraft at 20 km. In situ measurements of aerosol and cloud microphysical...
Topics: NASA Technical Reports Server (NTRS), AEROSOLS, CLOUD PHYSICS, FIRES, FLIGHT TESTS, INFRARED...
Nitrogen (N) fertilization of agricultural systems is thought to be a major source of the increase in atmospheric N2O; NO emissions from soils have also been shown to increase due to N fertilization. While N fertilizer use is increasing rapidly in the developing world and in the tropics, nearly all of our information on gas emissions is derived from studies of temperate zone agriculture. Using chambers, we measured fluxes of N2O and NO following urea fertilization in tropical sugar cane systems...
Topics: NASA Technical Reports Server (NTRS), AGRICULTURE, ATMOSPHERIC COMPOSITION, EXHAUST EMISSION,...
Significant sources of uncertainty in global trace gas budgets are due to lack of knowledge concerning the areal and temporal extent of source and sink areas. Synthetic aperture radar (SAR) is particularly suited to studies of northern ecosystems because of its all-weather operating capability which enables the acquisition of seasonal data. As key controls on methane exchange, the ability to differentiate major vegetation communities, inundation, and leaf area index (LAI) with satellite and...
Topics: NASA Technical Reports Server (NTRS), SYNTHETIC APERTURE RADAR, ATMOSPHERIC COMPOSITION, ARCTIC...
The study of the geology of multiring impact basins on the Moon over the past ten years has given us a rudimentary understanding of how these large structures have formed and evolved on the Moon and other bodies. Two-ring basins on the Moon begin to form at diameters of about 300 km; the transition diameter at which more than two rings appear is uncertain, but it appears to be between 400 and 500 km in diameter. Inner rings tend to be made up of clusters or aligned segments of massifs and are...
Topics: NASA Technical Reports Server (NTRS), STRUCTURAL BASINS, GEOLOGY, MOON, CRATERS, IMPACT MELTS,...
UARS data sets provide global coverage for the distributions of trace gases, which gives us an excellent chance to utilize the data set for model-data intercomparison studies. In the past three months, we have been working on the comparisons of the UARS data between 1992 (a half year after the Pinatubo eruption) and 1993 (one and a half year after the eruption) in an attempt to see how the Pinatubo volcanic eruption may have impacted stratospheric chemistry.
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC MODELS, STRATOSPHERE, VOLCANOLOGY, ATMOSPHERIC...
The X-Ray Microprobe on beamline X-26A at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory was used to determine the abundances of elements from Cr through Sr in individual interplanetary dust particles (IDPs) collected from the Earth's stratosphere and the Scanning Transmission X-ray Microscope (STXM) on beamline X-1A at the NSLS was used to determine the carbon abundances and spatial distributions in IDPs. In addition, modeling was performed in an attempt to...
Topics: NASA Technical Reports Server (NTRS), TRACE ELEMENTS, COSMIC DUST, ABUNDANCE, X RAY ANALYSIS, LIGHT...
Our studies are highly interdisciplinary, but are focused on the processes and products of early planetary and asteroidal differentiation, especially the genesis of the ancient lunar crust. Most of the accessible lunar crust consists of materials hybridized by impact-mixing. Rare pristine (unmixed) samples reflect the original genetic diversity of the early crust. We studied the relative importance of internally generated melt (including the putative magma ocean) versus large impact melts in...
Topics: NASA Technical Reports Server (NTRS), IGNEOUS ROCKS, PLANETARY COMPOSITION, BRECCIA, GEOCHRONOLOGY,...
The Mars Exploration Rovers each carry a set of Magnetic Properties Experiments designed to investigate the properties of the airborne dust in the Martian atmosphere. It is a preferred interpretation of previous experiments that the airborne dust in the Martian atmosphere is primarily composed by composite silicate particles containing one or more highly magnetic minerals as a minor constituent. The ultimate goal of the magnetic properties experiments on the Mars Exploration Rover mission is to...
Topics: NASA Technical Reports Server (NTRS), DUST, MARS ATMOSPHERE, MINERALS, TRACE ELEMENTS, VOLCANOES,...
Water vapor absorption is ubiquitous in the infrared wavelength range where photoacoustic trace gas detectors operate. This technique allows for discontinuous wavelength tuning by temperature-jumping a laser diode from one range to another within a time span suitable for photoacoustic calibration. The use of an internal calibration eliminates the need for external calibrated reference gases. Commercial applications include an improvement of photoacoustic spectrometers in all fields of use.
Topics: NASA Technical Reports Server (NTRS), WATER VAPOR, TRACE CONTAMINANTS, INFRARED SPECTRA,...
We present preliminary results in the development of a miniaturized gas correlation radiometer that implements a hollow-core optical fiber (hollow waveguide) gas correlation cell. The substantial reduction in mass and volume of the gas correlation cell makes this technology appropriate for an orbital mission -- capable of pinpointing sources of trace gases in the Martian atmosphere. Here we demonstrate a formaldehyde (H2CO) sensor and report a detection limit equivalent to approximately 30 ppb...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC COMPOSITION, FORMALDEHYDE, MARS ATMOSPHERE,...
Titan's northern spring equinox occurred in August 2009. General Circulation Models (e.g. Lebonnois et al., 2012) predict strong modifications of the global circulation in this period, with formation of two circulation cells instead of the pole-to-pole cell that occurred during northern winter. This winter single cell, which had its descending branch at the north pole, was at the origin of the enrichment of molecular abundances and high stratopause temperatures observed by Cassini/CIRS at high...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC GENERAL CIRCULATION MODELS, AEROSOLS, ANNUAL...
We report fluxes and dry deposition velocities for 16 atmospheric compounds above a southeastern United States forest, including: hydrogen peroxide (H2O2), nitric acid (HNO3), hydrogen cyanide (HCN), hydroxymethyl hydroperoxide, peroxyacetic acid, organic hydroxy nitrates, and other multifunctional species derived from the oxidation of isoprene and monoterpenes. The data suggest that dry deposition is the dominant daytime sink for small, saturated oxygenates. Greater than 6 wt %C emitted as...
Topics: NASA Technical Reports Server (NTRS), DEPOSITION, OXIDATION, FORESTS, DRYING, ATMOSPHERIC...
3
3.0
May 16, 2019
05/19
by
Iyengar, G. V. (Govindaraja V.)
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v. : 27 cm
Topics: Biochemistry -- Technique, Trace elements -- Analysis
The investigation of atmospheric pollution to determine the anion-containing particulates in the atmosphere at altitudes between 9.6 and 13.7 km is discussed. Air samples collected on cellulose fiber discs impregnated with dibutoxyethylphthalate require very sensitive methods of analysis. It is concluded that ion chromatography is suited for the determination of anions collected on the filters. Methods to control contamination and interfering side reactions are described.
Topics: NASA Technical Reports Server (NTRS), AIR FILTERS, AIR POLLUTION, ANIONS, GAS CHROMATOGRAPHY, HIGH...
Research progress is briefly outlined in the areas of activation experiments, enchanced mode conversion experiments, converter development (tungsten emitter, lanthanum hexaborate collector), and hot shell development.
Topics: NASA Technical Reports Server (NTRS), ACTIVATION ANALYSIS, THERMIONIC EMISSION, THERMIONIC POWER...
Data are reported for volatile/mobile Ag, As, Au, Bi, Cd, Co, Cs, Cu, Ga, In, Rb, Sb, Se, Te, T1 and Zn in exterior and/or interior samples of four Antarctic meteorites: 77005 (unique achondrite); 77257 (unreilite); 77278 (L3); 77299 (H3). Exterior samples reflect contamination and/or leaching by weathering but trace element (ppm-ppt) contents in interior samples seem reasonable for representatives of these rare meteoritic types. The 77005 achondrite seems related to shergottites; other samples...
Topics: NASA Technical Reports Server (NTRS), ANTARCTIC REGIONS, CONCENTRATION (COMPOSITION), METEORITES,...
Physical properties and chemical compositions of six synthetic crudes were determined. The results were compared to those of typical petroleum crudes, with the interest being the feasibility of making jet fuels from oil shale and coal syncrudes. The specific gravity, viscosity, and pour point were measured, showing that these crudes would be described as heavier rather than lighter crudes. The boiling range distribution of the crudes was determined by distillation and by gas chromatography. In...
Topics: NASA Technical Reports Server (NTRS), CRUDE OIL, JET ENGINE FUELS, SYNTHETIC FUELS, CHEMICAL...
A progress report and data analyses from the December 1980 flight are presented. The following areas are covered: (1) computer analysis of the flight spectra to obtain phase corrected, normalized sums of spectra for retrieval of atmospheric profiles; (2) study of atmospheric HF, HCl, and H2O; (3) stratospheric H2O2 and HOCl; (4) laboratory spectroscopy of HOCl; and (5) design study of a new balloon gondola. The majority of the flight data were taken in the low background mode, i.e., one input...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC COMPOSITION, GAS COMPOSITION, GASES, INFRARED...
Topics addressed include: meteorite concentration mechanisms; meteorites and the Antarctic ice sheet; iron meteorites; iodine overabundance in meteorites; entrainment, transport, and concentration of meteorites in polar ice sheets; weathering of stony meteorites; cosmic ray records; radiocarbon dating; element distribution and noble gas isotopic abundances in lunar meteorites; thermoanalytical characterization; trace elements; thermoluminescence; parent sources; and meteorite ablation and...
Topics: NASA Technical Reports Server (NTRS), ABUNDANCE, ANTARCTIC REGIONS, COSMOCHEMISTRY,...
Samples collected by the National Center for Atmospheric Research (NCAR) using the multiple-filter sampler on the U-2 were analyzed. The sampler is capable of exposing a number of 110 mm filters in sequence to ram air flow. Two types of filters, IPC cellulose and polystrene, were used, both of which have high blank levels for the trace elements determined. The levels of most trace elements in the stratosphere are so low under normal circumstances that none can be seen. Results from the eruption...
Topics: NASA Technical Reports Server (NTRS), AEROSOLS, ANALYZERS, ATMOSPHERIC COMPOSITION, CHEMICAL...
Quartz grains displaying multiple sets of planar features are described from numerous Cretaceous-Tertiary (K-T) boundary clays and claystones at both marine and nonmarine depositional sites around the world. All these sites also show anomalously high amounts of iridium and enrichments of other siderophile elements in cosmic ratios within these boundary units. This combination of mineralogical and geochemical features are used in support of an impact hypothesis for the end-Cretaceous event....
Topics: NASA Technical Reports Server (NTRS), CLAYS, DEPOSITS, ENRICHMENT, GEOCHEMISTRY, GEOCHRONOLOGY,...
Geochemical studies have been performed on thousands of rock samples collected across bio-event horizons in the fossil record using INAA for about 40 common and trace elements and radiochemical isolation procedures for Os, Ir, Pt, and Au on selected samples. These studies were begun soon after the Alvarez team announced their discovery of the Cretaceous-Tertiary (K-T) Ir anomaly in marine rock sequences in Europe. With their encouragement the Authors searched for the anomaly in nearby...
Topics: NASA Technical Reports Server (NTRS), GEOCHEMISTRY, GEOCHRONOLOGY, IRIDIUM, RADIOCHEMICAL...
The objectives were to: explain the abundances of siderophile elements in the SNC meteorite suite, of putative Martian origin; discover the magmatic origins and possibly magma compositions behind the Nakhla meteorite, one of the SNC meteorites; and a re-evaluation of the petrology of Angra dos Reis, a unique meteorite linked to the earliest planetary bodies of the solar nebula. A re-evaluation of its petrography showed that the accepted scenario for its origin, as a cumulate igneous rock, was...
Topics: NASA Technical Reports Server (NTRS), ACHONDRITES, BASALT, IRON METEORITES, METEORITIC COMPOSITION,...
Neutron activation analysis was performed for major and trace elements on a suite of eucrites from both Antarctic and non-Antarctic sources. The chemistry was examined to see if there was an easy way to distinguish Antarctic eucrites that had been disturbed in their trace elements systematics from those that had normal abundances relative to non-Antarctic eucrites. There was no simple correlation found, and identifying the disturbed meteorites still remains a problem. In addition, a set of...
Topics: NASA Technical Reports Server (NTRS), ANTARCTIC REGIONS, METEORITES, METEORITIC COMPOSITION,...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC CHEMISTRY, ATMOSPHERIC COMPOSITION, ATMOSPHERIC...
A two dimensional (altitude and latitude) model of the atmosphere is used to investigate problems relating to the variability of the dynamics and temperature of the atmosphere on the ozone distribution, solar cycle variations of atmospheric constituents, the sensitivity of model results to tropospheric trace gas sources, and assessment computations of changes in ozone related to manmade influences. In a comparison between two dimensional model results in which the odd nitrogen family was...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC COMPOSITION, ATMOSPHERIC TEMPERATURE, OZONE,...
The main objective of the theoretical studies presented here is to apply models of stratospheric chemistry and transport in order to understand the processes that control stratospheric ozone and that are responsible for the observed variations. The model calculations are intended to simulate the observed behavior of atmospheric ozone over the past three decades (1955-1985), for which there exists a substantial record of both ground-based and, more recently, satellite measurements. Ozone...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC CHEMISTRY, ATMOSPHERIC COMPOSITION, ATMOSPHERIC...
Stratospheric temperatures for long-term and recent trends and the determination of whether observed changes in upper stratospheric temperatures are consistent with observed ozone changes are discussed. The long-term temperature trends were determined up to 30mb from radiosonde analysis (since 1970) and rocketsondes (since 1969 and 1973) up to the lower mesosphere, principally in the Northern Hemisphere. The more recent trends (since 1979) incorporate satellite observations. The mechanisms that...
Topics: NASA Technical Reports Server (NTRS), AEROSOLS, ATMOSPHERIC COMPOSITION, ATMOSPHERIC TEMPERATURE,...
