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

Description: 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.
Partner: UNT Libraries Government Documents Department
open access

The quest for greenhouse-constrained technologies amid other concerns for environment and energy

Description: As we approach the 21st century, sentiments run high in the US for improved air quality in our cities and for a more secure energy future, hopefully to be manifest in lesser dependence on foreign supplies of oil. These sentiments are reflected in intense political activity on both the federal and state levels to enact legislation that will help alleviate both problems. At the same time though, the recent emergence of awareness of a threat of global warming due to ever increasing emissions of gr… more
Date: January 1, 1991
Creator: McGill, R.N.
Partner: UNT Libraries Government Documents Department
open access

The IGAC activity for the development of global emissions inventories: Description and initial results

Description: Modeling assessments of the atmospheric chemistry, air quality and climatic conditions of the past, present and future require as input inventories of emissions of the appropriate chemical species constructed on appropriate spatial and temporal scales. The task of the Global Emissions Inventories Activity (GEIA) of the International Global Atmospheric Chemistry Project (IGAC) is the production of global inventories suitable for a range of research applications. Current GEIA programs are general… more
Date: February 1, 1992
Creator: Benkovitz, C.M. (Brookhaven National Lab., Upton, NY (United States)) & Graedel, T.E. (AT and T Bell Labs., Murray Hill, NJ (United States))
Partner: UNT Libraries Government Documents Department
open access

Soot in the stratosphere: The impact of current and HSCT aircraft emissions

Description: One of the trace components of emissions from aircraft engines and other combustion sources are soot particles. These particles are strongly absorbing in the visible and IR spectra, may act as condensation nuclei, and may provide a large surface area for the catalytic promotion of gas-phase chemical reactions. Soot if found throughout the troposphere, even at remote locations, and also in the stratosphere. Present techniques do not allow an unambiguous identification of the sources. This paper … more
Date: August 1, 1991
Creator: Hansen, A.D.A. (Lawrence Berkeley Lab., CA (United States)); Pueschel, R.F. & Snetsinger, K.G. (National Aeronautics and Space Administration, Moffett Field, CA (United States). Ames Research Center)
Partner: UNT Libraries Government Documents Department
open access

Estimated increases in the cost of electricity under three acid-rain control bills

Description: Several bills were introduced in the past two Congresses to reduce emissions of sulfur dioxide and nitrogen oxides from electric power plants. The effects of these bills on electricity costs depend on features of the bills, on the mix of generating capacity owned by different electric utilities, on the technologies available for complying with the legislation, and on the time horizon used to calculate the costs. A system of computer software has been developed to make utility-specific estimates… more
Date: January 1, 1991
Creator: Hillsman, E .L. & Alvic, D. R.
Partner: UNT Libraries Government Documents Department
open access

Regional analysis of S emission-deposition trends in North America from 1979 through 1988

Description: Variations in SO{sub x} emissions weighted by a regional deposition model are shown to account for most of the variance in regionally averaged annual wet deposition (WD) and precipitation-weighted concentrations (PWCs) of sulfate in the United States and Canada during the period 1979--1988. Total emissions decreased about 15% during that time. For all sites combined, weighted emissions accounted for about two-thirds of the variance, with slightly better performance for PWC than for WD. Restrict… more
Date: January 1, 1991
Creator: Shannon, J.D.
Partner: UNT Libraries Government Documents Department
open access

Environmental issues in planning building energy technologies R D in the United States

Description: The US Department of Energy's Office of Building Technologies (OBT) has begun studies on the relationship and impact of buildings energy use on the environment, particularly with respect to global climate change, acid rain, stratospheric ozone depletion, and indoor air quality. The paper presents an overview of international and US federal activity in global change to set OBT's activities in context. The paper then reviews briefly the contribution of buildings to atmospheric problems through bu… more
Date: August 1, 1991
Creator: Farhar, B.C. (Solar Energy Research Inst., Golden, CO (United States)); Abel, F.H. (USDOE, Washington, DC (United States)); Nicholls, A.K. (Pacific Northwest Lab., Richland, WA (United States)) & Millhone, J.P. (USDOE Assistant Secretary for Conservation and Renewable Energy, Washington, DC (United States). Office of the Deputy Assistant Secretary for Building Technologies)
Partner: UNT Libraries Government Documents Department
open access

Efficiencies of free-air gas fumigation devices

Description: One of the key uncertainties relative to future increases in atmospheric CO{sub 2} is the extent to which growth in future emissions will be accommodated by increased uptake by terrestrial vegetation, the so-called fertilization'' effect. Research on this issue is currently pursued by many research groups around the world, using various experimental protocols and devices. These range from leaf cuvettes to various types of enclosures and glass-houses to various types of open-field gas enrichment… more
Date: March 1, 1992
Creator: Lipfert, F. W.; Hendrey, G. R.; Lewin, K. F. & Nagy, J.
Partner: UNT Libraries Government Documents Department
open access

The efficient use of natural gas in transportation

Description: Concerns over air quality and greenhouse gas emissions have prompted discussion as well as action on alternative fuels and energy efficiency. Natural gas and natural gas derived fuels and fuel additives are prime alternative fuel candidates for the transportation sector. In this study, we reexamine and add to past work on energy efficiency and greenhouse gas emissions of natural gas fuels for transportation (DeLuchi 1991, Santini et a. 1989, Ho and Renner 1990, Unnasch et al. 1989). We add to p… more
Date: January 1, 1992
Creator: Stodolsky, F. & Santini, D. J.
Partner: UNT Libraries Government Documents Department
open access

Simulations of greenhouse trace gases using the Los Alamos chemical tracer model

Description: Through three-dimensional global model studies on atmospheric composition and transport, we are improving our quantitative understanding of the origins and behavior of trace gases that affect Earth's radiative energy balance and climate. We will focus, in this paper, on the simulations of three individual trace gases including CFC-11, methyl chloroform, and methane. We first used our chemical tracer model to study the global distribution and trend of chemically inert CFC-11 observed by the Atmo… more
Date: November 1, 1991
Creator: Kao, C.Y.J.; Morz, E. (Los Alamos National Lab., NM (United States)) & Tie, X. (Scripps Institution of Oceanography, San Diego, CA (United States))
Partner: UNT Libraries Government Documents Department
open access

A comparison of policies to mitigate US greenhouse gas emissions

Description: The Congress of the United States requested that the Secretary of Energy: Prepare a report for the Congress that comprehensively inventories the sources of carbon dioxide (CO{sub 2}) and arranges the policy options to be formulated in cooperation with the Environmental Protection Agency (including, but not limited to, energy pricing, energy efficiency requirements, alternative fuels, alternative end use, and supply technology) which would lead to a substantial reduction in CO{sub 2} emissions. … more
Date: July 1, 1991
Creator: Edmonds, J.A.; McDonald, S.C. (Pacific Northwest Lab., Washington, DC (United States)) & Bradley, R.A. (USDOE, Washington, DC (United States))
Partner: UNT Libraries Government Documents Department
open access

Potential changes in atmospheric chemistry in the decades ahead: Climate and biosphere interactions and feedbacks

Description: Atmospheric chemistry is a challenging area of research where much knowledge is needed if we are to continue to survive as a species. This paper outlines research needs in the decades ahead in this key area of scientific endeavor. Highlighted are areas of research that are likely to lead to climatic and biospheric impacts and have been given little attention in the past. In particular, the possible organic transformation chemistries that may lead to chemical and physical changes in tropospheric… more
Date: October 1, 1991
Creator: Gaffney, J.S. & Marley, N.A.
Partner: UNT Libraries Government Documents Department
open access

Issues relevant to the development of coupled chemistry/climate models

Description: Our belief that climate will inexorably change is driven by the very clear evidence of chemical abundance changes in the atmosphere during the last four decades. In the past, this belief has led to the development of two separate efforts: to understand and build models to describing the physical climate system and to understand and build models of the chemical climate system. But how will these two systems interact? Are there important chemical changes that result from climate change that need … more
Date: September 1, 1994
Creator: Penner, J. E.; Austin, J.; Cariolle, D.; Kelder, H.; Kylling, A.; Prather, M. J. et al.
Partner: UNT Libraries Government Documents Department
open access

Long term modeling of the links between economics, technical progress and environment: Evolution of approaches and new trends

Description: This paper examines the evolution of modeling on greenhouse as emissions. The paper briefly highlights the origins and early efforts to model greenhouse gas emissions, efforts subsequent to 1988, and the shape of the next generation of greenhouse gas emissions models. Particular emphasis is placed on the author`s own contributions, including the Edmonds-Reilly Model and the second generation model.
Date: October 1, 1992
Creator: Edmonds, J.
Partner: UNT Libraries Government Documents Department
open access

Impact of biomass burning on the atmosphere

Description: Fire has played an important part in biogeochemical cycling throughout most of the history of our planet. Ice core studies have been very beneficial in paleoclimate studies and constraining the budgets of biogeochemical cycles through the past 160,000 years of the Vostok ice core. Although to date there has been no way of determining cause and effect, concentration of greenhouse gases directly correlates with temperature in ice core analyses. Recent ice core studies on Greenland have shown that… more
Date: March 1, 1993
Creator: Dignon, J.
Partner: UNT Libraries Government Documents Department
open access

Microphysical and compositional influences on shortwave radiative forcing of climate by sulfate aerosols

Description: Anthropogenic sulfate aerosols scatter shortwave (solar) radiation iincident upon the atmosphere, thereby exerting a cooling influence on climate relative to pre-industrial times. Previous estimates of this forcing place its global and annual average value at about {minus}1 W M{sup {minus}2}, uncertain to a factor of somewhat more than 2, comparable in magnitude to greenhouse gas forcing over the same period but opposite in sign and much more uncertain. Key sources of uncertainty are atmospheri… more
Date: February 1, 1995
Creator: Schwartz, S. E.; Wagener, R. & Nemesure, S.
Partner: UNT Libraries Government Documents Department
open access

A comparison of policies to mitigate US greenhouse gas emissions

Description: The Congress of the United States requested that the Secretary of Energy: Prepare a report for the Congress that comprehensively inventories the sources of carbon dioxide (CO{sub 2}) and arranges the policy options to be formulated in cooperation with the Environmental Protection Agency (including, but not limited to, energy pricing, energy efficiency requirements, alternative fuels, alternative end use, and supply technology) which would lead to a substantial reduction in CO{sub 2} emissions. … more
Date: July 1, 1991
Creator: Edmonds, J. A.; McDonald, S. C. & Bradley, R. A.
Partner: UNT Libraries Government Documents Department
open access

I think that I shall never see {hor_ellipsis} a lovely forestry policy: Land use programs for conservation of forests

Description: Forestry programs are frequently invoked as having potential for mitigation of greenhouse gas emissions. Most studies have attempted to quantify the potential impact of forest programs on carbon uptake and the potential costs of such programs. In this paper, we will attempt instead to focus on the institutional issues of the implementation of forestry programs for carbon sequestration. In particular, we explore the challenges for implementing forest programs that are: of increasing technologica… more
Date: January 1, 1994
Creator: Rayner, S. F. & Richards, K. R.
Partner: UNT Libraries Government Documents Department
open access

A Report on Workshops: General Circulation Model Study of Climate- Chemistry Interaction

Description: This report summarizes the discussion on General Circulation Model Study of Climate-Chemistry Interaction from two workshops, the first held 19--21 August 1992 at Oslo, Norway and the second 26--27 May 1993 at Albany, New York, USA. The workshops are the IAMAP activities under the Trace Constituent Working Group. The main objective of the two workshops was to recommend specific general circulation model (GCM) studies of the ozone distribution and the climatic effect of its changes. The workshop… more
Date: December 31, 1993
Creator: Wei-Chyung, Wang & Isaksen, I. S. A.
Partner: UNT Libraries Government Documents Department
open access

Efficiencies of free-air gas fumigation devices

Description: One of the key uncertainties relative to future increases in atmospheric CO{sub 2} is the extent to which growth in future emissions will be accommodated by increased uptake by terrestrial vegetation, the so-called ``fertilization`` effect. Research on this issue is currently pursued by many research groups around the world, using various experimental protocols and devices. These range from leaf cuvettes to various types of enclosures and glass-houses to various types of open-field gas enrichme… more
Date: March 1, 1992
Creator: Lipfert, F. W.; Hendrey, G. R.; Lewin, K. F. & Nagy, J.
Partner: UNT Libraries Government Documents Department
open access

Project report: Aircraft

Description: Analyses of scenarios of past and possible future emissions are an important aspect of assessing the potential environmental effects from aircraft, including the proposed high speed civil transport (HSCT). The development of a detailed three-dimensional database that accurately represents the integration of all aircraft emissions along realistic flight paths for such scenarios requires complex computational modeling capabilities. Such a detailed data set is required for the scenarios evaluated … more
Date: April 1, 1994
Creator: Wuebbles, D. J.; Baughcum, S.; Metwally, M. & Seals, R.
Partner: UNT Libraries Government Documents Department
open access

Greenhouse gas emissions related to ethanol produced from corn

Description: This report confers the details of a panel meeting discussion on greenhouse gases. The topic of this discussion was ethanol. Members discussed all aspects of growing corn and producing ethanol. Then the question was raised as to whether or not this is a suitable substitute to fossil fuel usage in the reduction of greenhouse gas emissions.
Date: April 1, 1994
Creator: Marland, G.
Partner: UNT Libraries Government Documents Department
open access

Life cycle analysis of energy systems: Methods and experience

Description: Fuel-cycle analysis if not the same as life-cycle analysis, although the focus on defining a comprehensive system for analysis leads toward the same path. This approach was the basis of the Brookhaven Reference Energy System. It provided a framework for summing total effects over an explicitly defined fuel cycle. This concept was computerized and coupled with an extensive data base in ESNS -- the Energy Systems Network Simulator. As an example, ESNS was the analytical basis for a comparison of … more
Date: August 1, 1992
Creator: Morris, S. C.
Partner: UNT Libraries Government Documents Department
open access

Reduction in global warming due to fuel economy improvements and emissions control of criteria pollutants: New US light-duty vehicles (1968--1991)

Description: This paper explores the impact of US emission controls and fuel economy improvements on the global warming potential (GWP) of new light-duty vehicles. Fuel economy improvements have reduced the GWP of both passenger cars and light-duty trucks by lowering the per mile emissions of carbon dioxide (CO{sub 2}). Further GWP reductions have been achieved by emission standards for criteria pollutants: carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NO{sub x}). The GWP of a criteria pollu… more
Date: August 1, 1992
Creator: Pitstick, M. E.; Santini, D. J. & Chauhan, H.
Partner: UNT Libraries Government Documents Department
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