Source gases: Concentrations, emissions, and trends

Source gases are defined as those gases that influence levels of stratospheric ozone (O3) by transporting species containing halogen, hydrogen, and nitrogen to the stratosphere. Examples are the CFC's, methane (CH4), and nitrous oxide (N2O). Other source gases that also come under consideration in an atmospheric O3 context are those that are involved in the O3 or hydroxyl (OH) radical chemistry of the troposphere. Examples are CH4, carbon monoxide (CO), and nonmethane hydrocarbons (NMHC's). Most of the source gases, along with carbon dioxide (CO2) and water vapor (H2O), are climatically significant and thus affect stratospheric O3 levels by their influence on stratospheric temperatures. Carbonyl sulphide (COS) could affect stratospheric O3 through maintenance of the stratospheric sulphate aerosol layer, which may be involved in heterogeneous chlorine-catalyzed O3 destruction. The previous reviews of trends and emissions of source gases, either from the context of their influence on atmospheric O3 or global climate change, are updated. The current global abundances and concentration trends of the trace gases are given in tabular format

Global atmospheric gases experiment (GAGE)

Issued as Semi-annual progress reports [nos. 1-5], Report, and Final status report, Project no. G-35-61

A three-dimensional dynamical-chemical model of the mesosphere and lower thermosphere

Issued as Quarterly reports no. 1-9, and Final report, Project no. G-35-60

Numerical simulation of an ice age paleoclimate

August 1972.Includes bibliographical references.Sponsored by the National Science Foundation GA-11637

Effects of spectral truncation on general circulation and long-range prediction

Includes bibliographical references

A Parallel Spectral Model for Atmospheric Transport Processes

This paper describes a parallel implementation of a grand challenge problem: global atmospheric modeling. The novel contributions of our work include: (1) a detailed investigation of opportunities for parallelism in atmospheric transport based on spectral solution methods, (2) the experimental evaluation of overheads arising from load imbalances and data movement for alternative parallelization methods, and (3) the development of a parallel code that can be monitored and steered interactively based on output data visualizations and animations of program functionality or performance. Code parallelization takes advantage of the relative independence of computations at different levels in the earth's atmosphere, resulting in parallelism of up to 40 processors, each independently performing computations for different atmospheric levels and requiring few communications between different levels across model time steps. Next, additional parallelism is attained within each level by taking advantage of the natural parallelism offered by the spectral computations being performed (eg., taking advantage of independently computable terms in equations). Performance measurements are performed on a 64-node KSR2 supercomputer. However, the parallel code has been ported to several shared memory parallel machines, including SGI multiprocessors

Case Study: An Integrated Approach for Steering, Visualization, and Analysis of Atmospheric Simulations

In the research described here, we have constructed at tightly coupled set of methods for monitoring, steering, an applying visual analysis to large scale simulations. a single, integrated approach. This work shows how a collaborative, interdisciplinary process that teams application and computer scientists can result in a powerful integrated approach. The integrated design allows great flexibility in the development and use of analysis tools. This work also shows that visual analysis is a necessary component for full understanding of spatially complex, time-dependent atmospheric processes