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in subjects: "Earth Atmosphere"

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Poleward leaping auroras, the substorm expansive and recovery phases and the recovery of the plasma sheet

The auroral motions and geomagnetic changes the characterize the substorm's expansive phase, maximum epoch, and recovery phase are discussed in the context of their possible associations with the dropout and, especially, the recovery of the magnetotail plasma sheet. The evidence that there may be an inordinately sudden large poleward excursion or displacement (a poleward leap) of the electrojet and the auroras at the expansive phase-recovery phase transition is described. The close temporal ass… more

Date: January 1, 1992

Creator: Hones, E.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Plasma sheet behavior during substorms

Auroral or magnetic substorms are periods of enhanced auroral and geomagnetic activity lasting one to a few hours that signify increased dissipation of energy from the magnetosphere to the earth. Data acquired during the past decade from satellites in the near-earth sector of the magnetotail have suggested that during a substorm part of the plasma sheet is severed from earth by magnetic reconnection, forming a plasmoid, i.e., a body of plasma and closed magnetic loops, that flows out of the tai… more

Date: January 1, 1983

Creator: Hones, E.W. Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Application of US upper wind data in one design of tethered wind energy systems

The upper atmospheric wind resource for the continental United States, Hawaii, and Alaska is assessed. The raw data were obtained from the National Center for Atmospheric Research, Boulder, Colo. The probability distributions of velocity are presented for 54 sites, and detailed calm wind analyses have been undertaken for five of these locations. On the average, the wind lulls about one day per week for a period in excess of about 30 hours. It is shown that the average power density of this wind… more

Date: February 1, 1982

Creator: O'Doherty, R. J. & Roberts, B. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Environmental Control Technology for Atmospheric Carbon Dioxide. Final Report

The impact of fossil fuel use in the US on worldwide CO/sub 2/ emissions and the impact of increased coal utilization on CO/sub 2/ emission rates are assessed. The aspects of CO/sub 2/ control are discussed as well as the available CO/sub 2/ removal sites. The primary factor affecting the practicability of a CO/sub 2/ control system is its energy requirements. Of the three potential CO/sub 2/ control points, removal from the stacks of fossil fuel power plants appears to require the least amount… more

Date: May 1, 1980

Creator: Albanese, A. S. & Steinberg, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Arctic Troposphere Carbon Dioxide: Low-Altitude Aircraft Sampling

Data from low altitude (<4500 m) aircraft sampling for CO/sub 2/ in the arctic atmosphere are presented. The data cover the period from late spring to late summer when environmental changes at the tundra and sea ice are most pronounced. Results of the data analysis show the effect of regional sources and sinks for CO/sub 2/ on the lower troposphere. The annual ice and open water zones of the Arctic Ocean covered by the flights transects appear to act as a potential sink for carbon dioxide.

Date: January 1, 1982

Creator: Gosink, Thomas A. & Kelley, John J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Proceedings of the workshop on the modification of the upper atmosphere by Satellite Power System (SPS) propulsion effluents

Results of a workshop held in June 1979, to identify research needs for evaluating environmental impacts on the upper atmosphere (here defined as greater than 70 km) due to Satellite Power System (SPS) transport, i.e., propulsion and reentry are presented. The substantial injections of water and hydrogen therefrom may lead to global-scale regions of reduced ionization in the ionospheric F-Region that may have a serious impact on worldwide HF radio communications; and the resulting possibly sign… more

Date: June 1, 1980

Creator: Bauer, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Role of the Qinghai-Xizang plateau in feedback mechanisms affecting the planetary circulation

It has been recognized for some time that the Qinghai-Xizang plateau is of great importance in generating planetary long-waves which, in resonance with similar waves induced by the Rocky Mountains, lead to the familiar pattern of quasi-stationary Rossby waves observed on monthly-mean upper level pressure charts. Seasonal forcing of flow patterns also appears to be particularly strong in the Qinghai-Xizang plateau region. Recent investigations suggest that the Qinghai-Xizang plateau may also be … more

Date: 1980~

Creator: Reiter, Elmar R. & Ding, Yi-Hui

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Sources and Sinks of Carbon Dioxide in the Arctic Regions

The data base required to adequately ascertain seasonal source and sink strengths in the arctic regions is difficult to obtain. However, there are now a reasonable quantity of data for this polar region to estimate sources and sinks within the Arctic which may contribute significantly to the annual tropospheric CO/sub 2/ concentration fluctuation. The sea-ice-air and the sea-air interfaces account for most of the contribution to the sources and sinks for carbon dioxide. Although the arctic and … more

Date: January 1, 1982

Creator: Gosink, T. A. & Kelley, J. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Energy and technology review

Research in three areas is described: (1) we are analyzing designs and materials for improving tank track pads to extend their service life and reduce their replacement costs; (2) after nearly a decade of study, we have arrived at two conclusions concerning ozone in the atmosphere: first, that the factors affecting atmospheric ozone concentrations are far more complex than first believed and, second, that compensating effects make the depletion of total ozone less than originally expected; (3) … more

Date: May 1, 1982

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Microphysical/mesoscale aspects of nuclear winter and new directions in assessments

Recent results of model studies and sensitivity tests have shown the degree to which the intensity and duration of ''nuclear winter'' depends on the mass of soot and dust suspended, its optical properties, its vertical distribution in the atmosphere, and the residence time. The soot from urban fires is viewed as evolving during its dispersion from the early fire induced plumes, to cloud scale systems, to the mesoscale and larger systems. Micro-physical processes are perceived as operating withi… more

Date: June 1, 1985

Creator: Knox, J.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Effects of construction and operation of a satellite power system upon the magnetosphere

This is the final report of an initial assessment of magnetospheric effects of the construction and operation of a satellite power system. This assessment effort is based on application of present scientific knowledge rather than on original scientific research. As such, it appears that mass and energy injections of the system are sufficient to modify the magnetosphere substantially, to the extent of possibly requiring mitigation measures for space systems but not to the extent of causing major… more

Date: December 1, 1979

Creator: Chiu, Y. T.; Luhmann, J. G.; Schulz, M. & Cornwall, J. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Reduction of photosynthetically active radiation under extreme stratospheric-aerosol loads

The recently published hypothesis that the Cretaceous-Tertiary extinctions might be caused by an obstruction of sunlight is tested by model calculations. First we compute the total mass of stratospheric aerosols under normal atmospheric conditions for four different (measured) aerosol size distributions and vertical profiles. For comparison, the stratospheric dust masses after four volcanic eruptions are also evaluated. Detailed solar radiative transfer calculations are then performed for artif… more

Date: January 1, 1981

Creator: Gerstl, S.A.W. & Zardecki, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Global environmental transport models for tritium

In this paper we discuss some of the obstacles to the construction of credible models of global tritium transport for use in dose assessments. We illustrate these difficulties by comparing model predictions of environmental tritium levels with measurements. Monitoring of tritium has shown that specific activities in precipitation over land are typically higher by a factor of three to four than those in precipitation over the oceans. Experience with modeling CO/sub 2/ turnover in the oceans has … more

Date: January 1, 1985

Creator: Killough, G. G. & Kocher, D. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Atmospheric transport and dispersion modeling for the Hanford Environmental Dose Reconstruction Project

Radiation doses that may have resulted from operations at the Hanford Site are being estimated in the Hanford Environmental Dose Reconstruction (HEDR) Project. One of the project subtasks, atmospheric transport, is responsible for estimating the transport, diffusion and deposition of radionuclides released to the atmosphere. This report discusses modeling transport and diffusion in the atmospheric pathway. It is divided into three major sections. The first section of the report presents the atm… more

Date: July 1, 1991

Creator: Ramsdell, J.V.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Effects of rocket exhaust products in the thermosphere and ionsphere

This paper reviews the current state of understanding of the problem of ionospheric F-layer depletions produced by chemical effects of the exhaust gases from large rockets, with particular emphasis on the Heavy Lift Launch Vehicles (HLLV) proposed for use in the construction of solar power satellites. The currently planned HLLV flight profile calls for main second-stage propulsion confined to altitudes below 124 km, and a brief orbit circularization maneuver at apogee. The second stage engines … more

Date: February 1, 1980

Creator: Zinn, J. & Sutherland, C. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

SPS environmental effects on the upper atmosphere

The ionospheric effects and associated environmental impacts which may be produced during the construction and operation of a solar power satellite system are reviewed. Propellant emissions from heavy lift-launch vehicles are predicted to cause widespread ionospheric depletions in electron and ion densities. Collisional damping of the microwave power beam in the lower ionosphere can significantly enhance the local free electron temperatures. Thermal self-focusing of the power beam in the ionosp… more

Date: January 1, 1980

Creator: Duncan, L.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Hanford 67-series: a volume of atmospheric field diffusion measurements

This volume documents atmospheric diffusion experiments carried out at the Hanford reservation during the period 1967 to 1973. A total of 103 tracer releases during 54 release periods is tabulated. Multi-tracer releases (generally from different elevations) were made during most of the experimental periods. Release heights varied from ground level to an elevation of 111 m. Tracers were sampled simultaneously on as many as 10 arcs at distances of up to 12.8 km from the tracer release point. As m… more

Date: November 1, 1977

Creator: Nickola, P. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Implications of the 1100 UT March 22, 1979 CDAW 6 substorm event for the role of magnetic reconnection in the geomagnetic tail

The event of March 22, 1979 has been the object of a concentrated study effort as a part of the Coordinated Data Analysis Workshop activity designated CDAW-6. Energetic electron and magnetic field measurements from a set of four satellites aligned from 6.6 to 13 R/sub E/ at the 0200 LT meridian at the time of the magnetospheric substorm event of 1100 UT are presented. These data are used to show that a magnetic X-line formed spontaneously in the vicinity of 7 R/sub E/ in response to a steady bu… more

Date: January 1, 1983

Creator: Fritz, T.A.; Baker, D.N.; McPherron, R.L. & Lennartsson, W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Radiological and Environmental Research Division. Annual report, January-December 1978

The programs addressed by this Section's research activities continue to evolve. Work on dispersion over water near shorelines has grown to include a large component investigating the flux of pollutants to the surface. Early studies of thermal exchange from heated water surfaces led to a current emphasis on steam fog and on the exchange of gases across an air-water interface. Work on the optical and radiative effects of air pollutants commenced under the Multistate Atmospheric Power Production … more

Date: January 1, 1978

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Numerical simulations on ion acoustic double layers

A comprehensive numerical study of ion acoustic double layers has been performed for both periodic as well as for nonperiodic systems by means of one-dimensional particle simulations. For a nonperiodic system, an external battery and a resistance are used to model the magnetospheric convection potential and the ionospheric Pedersen resistance. It is found that the number of double layers and the associated potential buildup across the system increases with the system length.

Date: July 1, 1980

Creator: Sato, T. & Okuda, H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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User's guide to the Heffter Interactive-Terminal Transport Model (ARL-HITTM)

The transport section of the Air Resources Laboratories (ARL) Atmospheric Transport and Dispersion Model (ATAD, Heffter, 1980) has been revised and simplified for use on interactive computer terminals. The resulting model, called the Heffter Interactive-Terminal Transport Model (ARL-HITTM) calculates four trajectories per day from one origin, forward or backward in time, using observed rawinsonde and pibal data for North America as input to the model. Trajectories, of three days duration, are b… more

Date: April 1, 1980

Creator: Benkovitz, C. M. & Heffter, J. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Large-scale measurement of airborne particulate sulfur

An aerosol sampling and analysis system is described that represents an integral approach to large-scale monitoring of airborne particulate matter. During our two-year period 34,000 size-fractionated samples were collected by automated dichotomous samplers characterized by a particle size cutpoint of 2.4 ..mu..m. The total mass of the particulate matter was measured by beta-particle attenuation, and the elemental composition, including sulfur, was determined by photon-excited x-ray fluorescence… more

Date: August 1, 1977

Creator: Loo, B. W.; French, W. R.; Gatti, R. C.; Goulding, F. S.; Jaklevic, J. M.; Llacer, J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

REDAR: the radiation and environmental data acquisition and recorder system

REDAR (Radiation and Environmental Data Acquisition and Recorder), Model IV, is a multi-microprocessor, portable data acquisition and real time analysis system. It was recently designed for use in severe environments aboard helicopters, fixed-wing aircraft, and various land vehicles. Nuclear radiation measurement, geographic position, and environmental data are simultaneously acquired, displayed on a CRT and multiple LED readouts, and recorded on cartridge tapes for post mission analysis on min… more

Date: January 1, 1982

Creator: Jobst, J.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Tritium distribution in the environment in the vicinity of a chronic atmospheric source-assessment of the steady state hypothesis

The Savannah River Site (SRS) is a major radionuclide production center. Tritium has been released to the atmosphere over the 36 year period of operation. The tritiated water concentration of the atmosphere, rain, vegetation and food have been routinely monitored during this period. Special studies have been made of tritium in soils and in the organic fractions of these same materials. The available data suggest that the average tritium concentration in the components of the terrestrial environ… more

Date: January 1, 1990

Creator: Murphy, C. E. Jr.; Bauer, L. R. & Zeigler, C. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department