Recent Developments in the Estimation of Potential Effects of High Altitude Aircraft Emissions on Ozone and Climate


Book Description

A review is provided of recent (December 1976-June 1978) developments in problems associated with estimating the potential effects that aircraft emissions at cruise altitudes may have on the earth's protective ozone shield and/or surface climate. Background information is provided as deemed necessary for context. The review shows that one recently measured key reaction rate(HO2 + NO yields NO2 + HO) has had dramatic effects on the ozone question. Computed effects on the ozone column of nitrogen oxides (which, unless in very large quantity, now cause an increase) and water vapor emissions (which, unless thermal feedback effects are included, cause a decrease) from supersonic transports (at 17-20 km) are now small and, on balance, apparently positive, at least for moderate fleets (several hundred aircraft). Subsonic aircraft also appear to cause small increases in the ozone column; however, on new modeling results are available. The new HO2 + NO rate has affected model duplication of the natural atmosphere adversely; another important new rate (HO2 + O3 yields HO + 2 O2), not yet incorporated in available results, may reduce this difficulty. Second-order effects (thermal feedback) have become important, particularly in modeling water effects; the modeling of water transport processes, however, involves many uncertainties. Additional modeling studies are needed. Progress in emissions measurement uncertainties and brief comments on possibly important climatic aspects are also included. (Author).




Stratospheric Ozone and Man


Book Description

The book, as originally conceived, was to be limited to technical considerations, but the scientific course of event has been so interwoven with non-scientific, but nevertheless related events, the authors felt necessary to include an account of this situation. Accordingly, the book is divided into five sections entitled: Stratospheric ozone Atmospheric processes influencing stratospheric ozone Does man influence stratospheric ozone Effects and research Public policy







Air Traffic and the Environment — Background, Tendencies and Potential Global Atmospheric Effects


Book Description

This volume contains ten papers on air traffic and the environment prepared by invited experts for a seminar organized by the German Aerospace Research Establishment (DLR) on November 15 and 16, 1990 in Bonn, Germany.







Scientific Application of Baseline Observations of Atmospheric Composition (SABOAC)


Book Description

The Southern Hemisphere commands an increasing interest among atmospheric chemists. It has smaller and less industrialized continents than the Northern Hemisphere and thus enjoys lower emissions of anthropogenic and biogenic pollu tants. As a consequence, the concentrations of trace species are lower in the Sou thern Hemisphere, giving rise to significant inter-hemispheric gradients. From an observation of the climatology of the various trace gas gradients important conclu sions on the chemical lifetimes, the distribution of sources and transport of trace species can be derived. Thus it is only fitting that the CSIRO Division of Atmos pheric Research, Aspendale, Australia, hosted the Conference on the Scientific Application of Baseline Observations of Atmospheric Composition (SABOAC). It was convened by Dr Graeme Pearman of the CSIRO and sponsored by the CSIRO and the Australian Bureau of Meteorology. Graeme Pearman and Ian Galbally of the CSIRO also agreed to serve as Guest Editors. The Conference was well attended and because of its location enjoyed an un usually large number of participants from the Southern Hemisphere. About 40 papers were presented with a large share of original contributions. At this point we would like to thank the reviewers who helped to maintain strict standards. The con ference topics ranged from Nonreactive Gases, Reactive Gases, Transport, Parti culates, Precipitation Chemistry, to Radiation and Carbondioxide. The present Proceedings do not quite maintain that sequence but partly reflect the order of receipt. DIETER EHHALT 3 Journal of Atmospheric Chemistry 3 (l985), 3-27.