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Global emissions inventories

Description: Atmospheric chemistry determines the concentrations of most of the important greenhouse gases except for carbon dioxide. The rate of removal of the greenhouse gases from the atmosphere is also controlled by atmospheric chemistry. The indirect effects of chemical forcing resulting from the chemical interactions of other species can also affect the concentrations of radiatively important gases such as ozone. In order to establish the contribution of any possible climatic change attributable to individual greenhouse gases, spatially and temporally resolved estimates of their emissions need to be established. Unfortunately, for most of the radiatively important species the global magnitudes of their individual fluxes are not known to better than a factor of two and their spatial distributions are even more poorly characterized. Efforts to estimate future projections of potential impacts and to monitor international agreements will require continued research to narrow the uncertainties of magnitude and geographical distribution of emissions.
Date: July 1, 1995
Creator: Dignon, J.
Partner: UNT Libraries Government Documents Department

An historic global SO2 emissions inventory for climate detection studies FY97 report to NOAA

Description: It has become apparent that anthropogenic aerosols exert radiative influence on the climate. This influence is comparable in magnitude but opposite in sign to that of greenhouse gases. The modeling effort here at LLNL has been designed to provide data and information for climate detection studies in order to help understand the role of anthropogenic aerosols over the interannual and decadal time scales.
Date: July 1, 1997
Creator: Dignon, J.
Partner: UNT Libraries Government Documents Department

Trace gas emission data bases for atmospheric chemistry studies

Description: Global data bases of trace gas emissions to the atmosphere have been compiled for the use in atmospheric chemistry studies. The resolution provided is a 1{degree} latitude by 1{degree} longitude. A series of 3 data bases has been provided. The first is an inventory of emissions of NO{sub x} from fossil fuel combustion, while the second is an inventory of SO{sub 2} emissions from the same anthropogenic source. The third database includes a global inventory of the emissions of NO{sub x} from terrestrial biomass burning and is given seasonally for the globe. The units of emission for the inventories are given as the mass in metric tons of N for the NO{sub x} inventories and metric tons of S for the SO{sub 2} inventory for each 1{degree} {times} 1{degree} grid. The emissions are expected to represent the emissions for the year 1980. The biomass burning source is given for 2 seasons where XXXXjul represents an ascii file containing the cumulated emissions for the months from April to September, and XXXXjan represents October to March. The grid for these data bases, (i,j) arrays, is (360,180), which represents 1 degree (lon,lat) resolution. The Table shows a description of each data base and provides FORTRAN code, documentation, and data format for reading each array. Complete description of the emission inventory data bases can be obtained in the references listed. 5 refs., 1 fig. 1 tab.
Date: October 7, 1991
Creator: Dignon, J.
Partner: UNT Libraries Government Documents Department

The WCRP`93 Workshop on the parameterization of sub-grid scale tracer transport: Results from the LLNL GRANTOUR model

Description: The primary goal of the WCRP Workshop is to improve the development of global chemical transport models by intercomparison of model parameterizations from the major modeling groups around the world. The Global Climate Research Division of LLNL has been invited to participate in this study. A secondary goal of the workshop is to understand how the current models transport short-lived chemical species. Chemical change in the troposphere of the important trace species such as OH and ozone are dependent on the distribution of NO{sub x}(=NO + NO{sub 2}) which is short-lived (hours to days) and has a wide variety of sources. Three case scenarios representing an A: surface source (natural radon source), B: aircraft source, and C: lightning source run for both the winter and summer seasons have been prescribed for the model intercomparison. The figures and tables presented in this report represent the results of running these 3 case scenarios with the Lagrangian version of the LLNL GRANTOUR model. Complete descriptions of the three case scenarios are given in Appendix A. Appendix B gives an example using the Case A: Dec-Jan-Feb, Natural Radon Source to describe the GRANTOUR run specifications. The other case runs for this report change only season and/or source of emissions.
Date: October 1, 1993
Creator: Dignon, J.
Partner: UNT Libraries Government Documents Department

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 significant climate change can be very rapid on the order of a decade. This chapter addresses the coupled evolution of our planet`s atmospheric composition and biomass burning. Special attention is paid to the chemical and climatic impacts of biomass burning on the atmosphere throughout the last century, specifically looking at the cycles of carbon, nitrogen, and sulfur. Information from ice core measurements may be useful in understanding the history of fire and its historic affect on the composition of the atmosphere and climate.
Date: March 1, 1993
Creator: Dignon, J.
Partner: UNT Libraries Government Documents Department

Remote Sensing of Alpha and Beta Sources - Modeling Summary

Description: Evaluating the potential for optical detection of the products of interactions of energetic electrons or other particles with the background atmosphere depends on predictions of change in atmospheric concentrations of species which would generate detectable spectral signals within the range of observation. The solar blind region of the spectrum, in the ultra violet, would be the logical band for outdoor detection (see Figure 1). The chemistry relevant to these processes is composed of ion-molecule reactions involving the initially created N{sub 2}{sup +} and O{sub 2}{sup +} ions, and their subsequent interactions with ambient trace atmospheric constituents. Effective modeling of the atmospheric chemical system acted upon by energetic particles requires knowledge of the dominant mechanism that exchange charge and associate it with atmospheric constituents, kinetic parameters of the individual processes (see e.g. Brasseur and Solomon, 1995), and a solver for the coupled differential equations that is accurate for the very stiff set of time constants involved. The LLNL box model, VOLVO, simulates the diel cycle of trace constituent photochemistry for any point on the globe over the wide range of time scales present using a stiff Gear-type ODE solver, i.e. LSODE. It has been applied to problems such as tropospheric and stratospheric nitrogen oxides, stratospheric ozone production and loss, and tropospheric hydrocarbon oxidation. For this study we have included the appropriate ion flux.
Date: October 20, 2005
Creator: Dignon, J; Frank, M & Cherepy, N
Partner: UNT Libraries Government Documents Department

Quantifying magnitudes and distributions of CO sources

Description: We use a simplified version of the GRANTOUR chemical tracer model to analyze emissions of CO from various sources. The GRANTOUR model has been simplified to include the eigenvalue chemistry solution method of Prather (1994). The analysis includes fossil fuel combustion, biomass burning, hydrocarbon oxidation, ocean, and terrestrial sources of CO. We also present a 1{degree} x 1{degree} emissions inventory of CO from fossil fuel combustion.
Date: March 1, 1998
Creator: Dignon, J.; Penner, J. E. & Walton, J. J.
Partner: UNT Libraries Government Documents Department

A black carbon emission data base for atmospheric chemistry and climate studies

Description: A global data base of black carbon emissions to the atmosphere from fossil fuel combustion has been compiled for the use in atmospheric chemistry and climate studies. The resolution provided is at 1{degree} latitude by 1{degree} longitude based on previous work by Matthews, Lemer et al., and Dignon. A more extensive description of the assumptions made and emission factors used in this data base can be found in Penner et al. The original work of Penner et al. provides the emissions inventory data on a 5{degree} by 5{degree} resolution. The units of emission for this updated version of the inventory yield a global total of 12.6 TgC/y and are given as the mass in metric tons of carbon for each 1{degree} x 1{degree} grid. It is important to note that this is not equivalent to a flux, in that the area of the grid boxes vary latitudinally. The emissions are expected to represent the emissions for a typical mid-1980s year. The distribution of emission is based on national totals and then mapped on to the 1{degree} x 1{degree} grid according to the updated population mapping of Logan. A description of this mapping procedure can be found in Dignon.
Date: October 1, 1994
Creator: Dignon, J.; Eddleman, H.E. & Penner, J.E.
Partner: UNT Libraries Government Documents Department

Impact of biomass burning on the atmosphere. Revision 1

Description: Fire has played an important part in biogeochemical cycling throughout much of the history of our plant. This report addresses the coupled evolution of our planet`s atmospheric composition and biomass burning. Special attention is paid to the chemical and climatic impacts of biomass burning on the atmosphere throughout the last century, specifically looking at the cycles of carbon, nitrogen, and sulfur. Information from ice core measurements may be useful in understanding the history of fire and its historic affect on the composition of the atmosphere and climate.
Date: April 1, 1994
Creator: Dignon, J.
Partner: UNT Libraries Government Documents Department

Results from the LLNL Eulerian GRANTOUR model for the WCRP `93 workshop on the parameterization of sub-grid scale tracer

Description: GRANTOUR is a 3D chemical transport model (CTM) developed at LLNL which has been applied to a diverse set of problems in the troposphere. GRANTOUR uses fields supplied by a GCM and calculates the advection of inert or chemically reactive trace species in a Lagrangian scheme. The atmosphere is divided into ``parcels`` of equal mass and the center of mass of each of these parcels is accurately advected in a Lagrangian manner with little or no numerical diffusion. The advantage of this approach is the accuracy of the advection, while the disadvantages of this scheme are the difficulties in resolving the stratosphere and accurately inferring fluxes from the movements of the center of masses of the parcels. An Eulerian option has recently been implemented in GRANTOUR which uses a second order Van Leer scheme to transport inert or reactive trace species through a fixed three dimensional grid. Although this new model introduces a small amount of numerical diffusion which the Lagrangian approach did not have, it provides the potential to accurately resolve the stratosphere and to diagnose important quantities such as fluxes across the equator or the tropopause.
Date: April 1, 1994
Creator: Bergmann, D.; Dignon, J.; Penner, J. & Walton, J.
Partner: UNT Libraries Government Documents Department

New Technologies for Standoff Assessment of Radiological Contamination

Description: Technologies to rapidly quantify surface activity with minimal worker contact would dramatically decrease the radiation dose a radiation worker receives in assessment and cleanup operations, while obtaining a clear image of exactly where dispersed contamination is located. LLNL efforts in the development of the Photochromic Radiation Dosimeter and the Imaging Assessment System will be described. Initial use of these technologies in decontamination and decommissioning of contaminated facilities demonstrates several significant advantages over standard techniques such as survey meters and swipes.
Date: May 6, 2005
Creator: Cherepy, N; Stevens, C; Wurtz, R; Sanner, R; Frank, M; Tillotson, T et al.
Partner: UNT Libraries Government Documents Department

Toward a New Era of Research in Aerosol/Cloud/Climate Interactions at LLNL

Description: One of the largest uncertainties in simulations of climate change over the industrial period is the impact of anthropogenic aerosols on the Earth's radiation budget. Much of this uncertainty arises from the limited capability for either precisely linking precursor gases to the formation and size distribution of the aerosols or quantitatively describing the existing levels of global aerosol loading. This project builds on our aerosol and chemistry expertise to address each of these uncertainties in a more quantitative fashion than is currently possible. With the current LDRD support, we are in the process to implement an aerosol microphysics module into our global chemistry model to more fundamentally and completely describe the processes that determine the distribution of atmospheric aerosols. Using this new modeling capability, in conjunction with the most current version of NCAR climate model, we will examine the influence of these processes on aerosol direct and indirect climate forcing.
Date: September 27, 2000
Creator: Chuang, C,; Dignon, J.; Grant, K.; Connell, P.; Bergman, D.; Rotman, D. et al.
Partner: UNT Libraries Government Documents Department

GRI methane chemistry program review meeting

Description: Methane is an important greenhouse gas which affects the atmosphere directly by the absorption and re-emission of infrared radiation as well as indirectly, through chemical interactions. Emissions of several important greenhouse gases (GHGS) including methane are increasing, mainly due to human activity. Higher concentrations of these gases in the atmosphere are projected to cause a decrease in the amount of infrared radiation escaping to space, and a subsequent warming of global climate. It is therefore vital to understand not only the causes of increased production of methane and other GHGS, but the effect of higher GHG concentrations on climate, and the possibilities for reductions of these emissions. In GRI-UIUC methane project, the role of methane in climate change and greenhouse gas abatement strategies is being studied using several distinct approaches. First, a detailed treatment of the mechanisms controlling each important methane source and sink, and hence the atmospheric concentration of methane, is being developed for use with the UIUC Integrated Science Assessment Model. The focus of this study is to resolve the factors which determine methane emissions and removal, including human population, land use, energy demand, global temperature, and regional concentrations of the hydroxyl radical, carbon monoxide, nitrous oxides, non-methane hydrocarbons, water vapor, tropospheric and stratospheric ozone.
Date: February 1, 1997
Creator: Dignon, J.; Grant, K.; Grossman, A.; Wuebles, D.; Brasseur, G.; Madronich, S. et al.
Partner: UNT Libraries Government Documents Department