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in subjects: "Atmospheric Circulation"

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Experimental and theoretical investigations of marine stratocumulus cloud sensitivity to climate parameters using ship-trail clouds

The formation and radiative properties of clouds are poorly parameterized in numerical climate models, especially marine boundary layer clouds. Twomey (1991), after describing the importance of cloud microphysics to the climate problem, states Clearly, many more field measurements and laboratory experiments are called for, rather than endless repetitions of computer simulations that are closely related to each other and parameterize in very similar ways.'' The effort described here is a field e… more

Date: January 1, 1991

Creator: Porch, W.; Buchwald, M.; Glatzmaier, T.; Kao, C.-Y.; Unruh, W. (Los Alamos National Lab., NM (United States)); Hudson, J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Surface footprint from initial Chernobyl release as indicated by the meso-alpha MLAM (Multi-Layer Air Mass) model

This document reports the results of dose calculations from the Chernobyl reactor accident in April 1986. The calculations were completed in 1987. The results are now being published to disseminate the information to an audience of potential users. This study's objective was to model the transport path of materials released during April 26 and 27, the first 48 hours of the accident. 5 refs., 15 figs.

Date: December 1, 1989

Creator: Davis, W. E.; Olsen, A. R.; Didier, B. T.; Tucker, P. E. & Damschen, D. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Influences of clouds and rain on the large-scale transport and deposition of sulfur

This paper describes the application of a three-dimensional, global-scale Eulerian model with an explicit description of cloud and chemical processes. Simulation results describing the transport of sulfur from North America and Europe across the north Atlantic Ocean during a climatological July are presented. Wet deposition was found to contribute slightly more to total sulfur deposition than dry deposition, a feature explained by the large amounts of precipitation during this month. The wet de… more

Date: July 1, 1991

Creator: Luecken, D.J.; Berkowitz, C.M. & Easter, R.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Development and testing of an air quality model for Mexico City

Los Alamos National Laboratory and Instituto Mexicano del Petroleo have embarked on a joint study of options for improving air quality in Mexico City. The intent is to develop a modeling system which can address the behavior of pollutants in the region so that option for improving Mexico City air quality can be properly evaluated. In February of 1991, the project conducted a field program which yielded a variety of data which is being used to evaluate and improve the models. Normally the worst … more

Date: March 2, 1992

Creator: Williams, M. D.; Streit, G. (Los Alamos National Lab., NM (United States)); Cruz, X.; Ruiz, M.; Sosa, G. (Instituto Mexicano de Petroleo, Mexico City (Mexico)); Russell, A. G. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Overview of climatic effects of nuclear winter

A general description of the climatic effects of a nuclear war are presented. This paper offers a short history of the subject, a discussion of relevant parameters and physical processes, and a description of plausible nuclear winter scenario. 9 refs. (ACR)

Date: January 1, 1985

Creator: Jones, E. M. & Malone, R. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Program report for FY 1984 and 1985 Atmospheric and Geophysical Sciences Division of the Physics Department

This annual report for the Atmospheric and Geophysical Sciences Division (G-Division) summarizes the activities and highlights of the past three years, with emphasis on significant research findings in two major program areas: the Atmospheric Release Advisory Capability (ARAC), with its recent involvement in assessing the effects of the Chernobyl reactor accident, and new findings on the environmental consequences of nuclear war. The technical highlights of the many other research projects are … more

Date: August 1, 1986

Creator: Knox, J. B.; MacCracken, M. C.; Dickerson, M. H.; Gresho, P. M. & Luther, F. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Atmospheric radiation measurement: A program for improving radiative forcing and feedback in general circulation models

The Atmospheric Radiation Measurement (ARM) Program is a key element of the Department of Energy's (DOE's) global change research strategy. ARM represents a long-term commitment to conduct comprehensive studies of the spectral atmospheric radiative energy balance profile for a wide range of cloud conditions and surface types, and to develop the knowledge necessary to improve parameterizations of radiative processes under various cloud regimes for use in general circulation models (GCMs) and rel… more

Date: January 1, 1991

Creator: Patrinos, A.A. (USDOE, Washington, DC (United States)); Renne, D.S.; Stokes, G.M. (Pacific Northwest Lab., Richland, WA (United States)) & Ellingson, R.G. (Maryland Univ., College Park, MD (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Analysis of general circulation model results and comparison with regional climatic data, Task 3

On time scales of greater than one year the variability of weather and climate on a large path of the Earth is dominated by the Southern Oscillation. While current theories of this phenomenon have clarified the role of the interaction between the ocean and the atmosphere in maintaining this oscillation it has so far been unclear whether the Southern Oscillation originates in the ocean, in the atmosphere or during the interaction between the ocean and the atmosphere. In this study we compared si… more

Date: January 1, 1989

Creator: Cess, R.D. & Hameed, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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ARM tropical pacific experiment (ATPEX): Role of cloud, water vapor and convection feedbacks in the coupled ocean/atmosphere system

We have initiated studies that include radiation model validation, improved treatment of the three-dimensional structure of cloud-radiation interactions, and sensitivity runs that will unravel the role of cloud-convection-radiation interactions in the Pacific Sear Surface Temperatures and the overlying Walker and Hadley circulation. The research program is divided into three phases: (1) radiation, (2) cloud parameterization issues; (3) feedback and ocean-atmosphere interactions.

Date: March 5, 1992

Creator: Ramanathan, V. & Barnett, T.P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Simulation of atmospheric dispersion of radioactivity from the Chernobyl accident

Measurements of airborne radioactivity over Europe, Japan, and the United States indicated that the release from the Chernobyl reactor accident in the Soviet Union on April 26, 1986 contained a wide spectrum of fission up to heights of 7 km or more within a few days after the initial explosion. This high-altitude presence of radioactivity would in part be attributable to atmospheric dynamics factors other than the thermal energy released in the initial explosion. Indications were that two types… more

Date: July 1, 1989

Creator: Lange, R.; Sullivan, T.J. & Gudiksen, P.H. (Lawrence Livermore National Lab., CA (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Meteorological conditions during the winter validation study at Rocky Flats, Colorado: An overview

The objective for the Winter Validation Study was to gather field data for validation of the Terrain-Responsive Atmospheric Code (TRAC) under winter time meteorological conditions. Twelve tracer tests were conducted during a two-week period in February 1991. Each test lasted 12 hours, with releases of SF{sub 6} tracer from the Rocky Flats Plant near Golden, Colorado. The tests included ground-based and airborne sampling to 16 km from the release point. This presentation summarizes meteorologica… more

Date: November 6, 1991

Creator: Hodgin, C.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Meteorological data summaries for the TFTR from January 1984 to December 1985

The first two years of meteorological data for the TFTR are reviewed and summarized.

Date: July 1, 1986

Creator: Kolibal, J.; Ku, L. P. & Liew, S. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Can sulfate fluxes in forest canopy throughfall be used to estimate atmospheric sulfur deposition

The flux of sulfate is forest throughfall and stemflow (the sum of which is designated here as TF) may be an indicator of the atmospheric deposition of S, particularly if foliar leaching of internal plant S is small relative to washoff of deposition. Extensive data from 13 forests indicate that annual sulfate fluxes in TF and in atmospheric deposition are very similar, and recent studies with {sup 35}S tracers indicate that leaching is only a few percent of total TF. However, some short-term de… more

Date: 1991~

Creator: Lindberg, S. E.; Garten, C. T. Jr.; Cape, J. N. & Ivens, W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Regional-scale simulations of the western United States climate

Mesoscale models can provide a sufficiently detailed regional climatology. From these pioneering studies, we were inspired to begin to develop regional climatologies with the Colorado State University Regional Atmospheric Modeling System (CSU-RAMS). Our major goal is to develop a better understanding of the hydrologic cycle in the mountainous, arid west. An advantage of using the RAMS code is that we can generate detailed descriptions of precipitation processes, which will hopefully translate i… more

Date: September 1, 1991

Creator: Bossert, J.E.; Kao, C.-Y.J. (Los Alamos National Lab., NM (United States)); Roads, J.O.; Chen, Shyh-C. & Ueyoshi, Kyozo (Scripps Institution of Oceanography, La Jolla, CA (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A 3-D dynamical/chemical GCM for simulating the anthropogenical effects on ozone

In spite of the significantly increased attention atmospheric ozone has received over the last two decades or so, a fully quantitative understanding of the three-dimensional ozone structure remains unavailable. In the past, one-dimensional (vertical column) models have provided most of the quantitative simulations of atmospheric chemical systems, because these models can treat large ensembles of chemical process economically. More recently, two-dimensional (meridional cross section) models have… more

Date: January 1, 1989

Creator: Kao, C. Y. J.; Glatzmaier, G. A.; Malone, R. C. & Turco, R. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

MESORAD dose assessment of the Chernobyl reactor accident

An accident involving Unit 4 of the Chernobylskaya Atomic Energy Station resulted in the release of a large amount of radioactive material to the atmosphere. This report describes the results of an assessment of the doses near the site (within 80 km) made at the Pacific Northwest Laboratory using the MESORAD Dose Assessment model. 6 refs., 10 figs., 5 tabs.

Date: December 1, 1989

Creator: Ramsdell, J.V.; Hubbe, J.M.; Athey, G.F. & Davis, W.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Development of a building wake/stack height numerical modeling capability

We are developing state-of-the-art numerical tools which can be used to provide reliable estimates of potential emissions at various LLNL sites. In particular we have focused our efforts in generating models which can simulate the wind flow and dispersion of airborne pollutants around surface-mounted structures such as buildings or building complexes. To achieve this goal, we have adopted two different but complementary approaches in the modeling of this complex problem. The first approach empl… more

Date: September 6, 1991

Creator: Lee, R.L. & McCallen, R.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

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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Numerical simulations of long-range pollutant transport from coast to inland mountainous regions

Kurita and Ueda (1986) presented an example of the long-range transport of pollutants which frequently occurs in summer in Japan light gradient wind conditions. High concentrations of photochemical oxidants were observed in late evenings in the mountainous region approximately 160 km northwest from the large industrial zone located along the Tokyo bay. Pollutants were apparently transported by the large-scale circulations produced by the combination of southwesterly valley winds induced by ther… more

Date: January 1, 1988

Creator: Yamada, Tetsuji; Bunker, S.S. & Niccum, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Review of Information on Hydrology and Radionuclide Migration at the Nevada Test Site 1976--1988, and Annotated Bibliography

The purpose of this report is to provide information on changes in the state of knowledge on the hydrology and radionuclide migration that have occurred at the Nevada Test Site (NTS) since 1976. In the present study, a literature review was conducted to examine information published since 1976 about the various activities that have occurred at the NTS. Information was collected from the literature on the site's geological, hydrological, geochemical, and geomorphic characteristics related t… more

Date: September 1989

Creator: Raymond, J. R.; Eddy, P. A.; Wallace, R. W.; Foley, M. G.; Bierschenk, W. H. & Harrison, R. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Real-time statistical quality control and ARM

An important component of the Atmospheric Radiation Measurement (ARM) Program is real-time quality control of data obtained from meteorological instruments. It is the goal of the ARM program to enhance the predictive capabilities of global circulation models by incorporating in them more detailed information on the radiative characteristics of the earth's atmosphere. To this end, a number of Cloud and Radiation Testbeds (CART's) will be built at various locations worldwide. Each CART will consi… more

Date: May 1, 1992

Creator: Blough, D.K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent changes of weather patterns in North America

The objectives of this report are (1) to analyze the time related changes and variability in the property and frequency of air masses and the weather extremes over North America; and, (2) to determine to what degree the observed changes agree with the predictions based on climate models. Climate models predict a general increase of surface air temperature and drought over parts of the North American continent due to increased CO{sub 2} concentrations. Regional climate change results in part fro… more

Date: April 1, 1992

Creator: Kukla, G.J. & Gavin, J.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Thermohaline circulations and global climate change

Thermohaline Circulations and Global Climate Change'' is concerned with investigating the hypothesis that changes in surface thermal and hydrological forcing of the North Atlantic, changes that might be expected to accompany CO{sub 2}-induced global warming, could result in ocean-atmosphere interactions' exerting a positive feedback on the climate system. Because the North Atlantic is the source of much of the global ocean's reservoir of deep water, and because this deep water could sequester l… more

Date: January 1, 1992

Creator: Hanson, H. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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2DPUF: A sequential gaussian puff model

This report documents the Environmental Transport Section's (ETS) two-dimensional, sequential gaussian puff transport and dispersion model for emergency response. The sequential puff scheme is described, and the dispersion equations are presented. The advantages of this model over the ETS's PUFF/PLUME model are discussed. Options are calculating a two-dimensional wind field, interpolation procedures, and the wind field grid are described. The various grid systems for puff transport calculations… more

Date: January 1, 1990

Creator: Addis, R.P. & O'Steen, B.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department