AND CONCLUSIONS OF THE WARSAW II MEETING ON ATMOSPHERIC COMPUTATIONS TO ASSESS ACIDIFICATION IN EUROPE JOSEPH ALCAMO and JERZY BARTNICKI International Institute for Applied Systems Analysis Schlossplatz 1, A-2361 Laxenburg, Austria (Received June 1, 1988; revised June 20, 1988) Abstract. Three topics are discussed in this report: sensitivity/uncertainty analysis of long range transport models, the interface between atmospheric models of different scales, and linkage between atmospheric and ecological models. In separate analyses oflong range transport models, it was found that uncertainty of annual S deposition was mostly affected by uncertainty of wind velocity, mixing height and wet deposition parameterization. Uncertain parameters collectively caused S deposition errors of around 10-25% (coefficient of variation) in the models examined. The effect of interannual meteorological variability on computed annual S deposition was relatively small. Different methods were presented for combining models of regional and interregional scale. It was found to be more important to include interregional information in regional-scale models for annual computations compared to episodic computations. A variety of linkage problems were noted between atmospheric and ecological models. The vertical distribution of pollutants and 'forest fittering' of pollutant deposition were found to be important in ecological impact calculations but lacking in the output of most interregional atmospheric models.

EUROTRAC is the EUREKA environmental project studying the transport and chemical transformation of pollutants in the troposphere over Europe. At its inception in 1988 it had three aims: * to increase the basic understanding of atmospheric science; * to promote the technological development of sensitive, specific, fast-response instrumentation for environmental research and monitoring; and * to improve the scientific basis for taking future political decisions on environmental management within Europe. It was clear at an early stage, as the fourteen subprojects were formed and more than two hundred research groups in twenty-four countries were incorporated, that the first aim would readily be achieved. An ample demonstration that the early indications were correct is provided in the other volumes in this series which describe the scientific progress made. Substantial progress was also made towards achieving the second aim although some problems were encountered, mainly due to the high cost of the technological development required.

Proceedings of the EEC Workshop organized within the Framework of the Concerted Action "Physico-Chemical Behaviour of Atmospheric Pollutants", held in Berlin, 9 September 1982