CAPMAN Report 2000 Summary

CAPMAN: Summary of Annual Report 2000

Atmospheric deposition is a major input route for pollution to coastal seas around Europe. Depending on time of year, nutrients may increase biological activity of phytoplankton and toxic algae in the surface layer of the sea, causing changes in the composition of the benthic fauna and flora, and affect the oxygen consumption within both the water column and sediments. Data on atmospheric fluxes of nutrients, especially inorganic and organic nitrogen and phosphorus compounds in the gaseous and particulate phases, are rather limited and sometimes even conflicting. Therefore, quantifying the inputs of various nutrient compunds including fixed nitrogen and trace metals to coastal waters is needed. In particular, there is a need to understanding the processes regulating these inputs and to describe their impacts on the biogeochemistry of surface waters.

During recent years, much research work has been carried out and new questions raised in the field of atmospheric deposition. Trace elements such as Al, Si, Mn and Fe are documented to be increasingly important due to their biological roles. The bio-availability of these trace elements is therefore also included among the investigations carried out under CAPMAN. In addition, Cr, Ni, Cu, Zn, Cd, and Pb, all defined by the North Sea Conference as toxic components with high priority, are given full attention as well, with special focus on the source-transport-sink inventories of Europe's coastal seas.

The anthropogenic activity responsible for chemical deposition to marine ecosystems, as well as local and regional air pollution episodes, can in most part be traced back to emissions from industrial, agricultural, and commercial enterprises. Understanding the source-receptor relationships, and assessing the benefits of emission reductions on coastal environmental quality, require the construction and implemention of well functioning atmospheric chemistry and transport models. Models must be capable of discerning the necessary spatial resolutions for local authorities, and they must also be capable of separating regional versus long range transported emissions as causes of local adverse conditions (e.g., whether air pollution exceedances or marine eutrophication). As models are developed, the appropriate technology must be in place to provide testing and validation.

In order to support the needs of coastal zone managers and policymakers, and to extend the atmospheric sciences under the frame of EUROTRAC-2, the overall aim of CAPMAN is to improve the science base necessary to extend the quality of relevant data bases, and extend the applicability and performance of coastal models. This aim is supported by four objectives:

(b) extending the understanding of aerosol mass closure and the role of organics;

Research reported under CAPMAN during 2000 included advances in theoretical frameworks, experimental techniques, and modelling approaches which are needed to improve estimates of surface exchanges in coastal regions. The study regions reported for 2000 include the North Sea (De Leeuw), Kattegat Strait between Denmark and Sweden (Sørensen, Jickells, Sempreviva), Baltic Sea (Smedman), and the Italian coastal zones of the Mediterranean Sea (Finardi). Theoretical work focussed on generalizing the flux profile relations for all chemical compounds (Geernaert), exploring dynamical relationships between swell waves and the air-sea momentum flux (Smedman), and on examining the rate of air mass transformation associated with internal boundary layer growth (Dunkerley, et al.).

Experimental studies during 2000 focussed on a major campaign in the Kattegat between Denmark and Sweden (Sørensen, Jickells, Sempreviva), which combined measurements from coastal and island stations to model derived data bases for the region. Analysis of both past and new data sets gathered in the Mediterranean, Baltic, and North Seas were integrated into the analysis, in order to generalize the results to other regions. There were continued field campaigns on the island of Gotland (Smedman), in order to study the interaction between swell waves and both the Monin-Obukhov similarity theory as well as its applications. In addition, there were continued field measurements in the Belgian and Dutch parts of the North Sea, as part of a long term effort to explore the controls over air-water exchange of nutrients, micro-pollutants, and trace metals (Van Grieken).

Modelling of air-sea inputs placed focus on the development of heterogeneous chemistry submodules, exploring various dynamical modelling techniques able to address the complex conditions of coastal zones, and assessing a variety of air quality regulatory models for use in assessing impacts of industrial and agricultural emissions in coastal zones. In support of the major field study in the Kattegat during 2000, the American model COAMPS was integrated into the modelling efforts (Svensson and Tjernström). The COAMPS model was integrated into the modelling activities in order to extend the performance of model systems applicable to the Skaggerak and Kattegat region.

Specific modelling projects were designed to examine a variety of related coastal issues. The seasonal variation of nutrient deposition to coastal seas was explored for the Danish coastal waters, with a view towards identifying the relative importance of atmospheric deposition to adverse marine biological states (Hertel). In Italy, studies were conducted in order to determine the relative importance of long range transported pollution, with a view towards new emissions control policies for northern Italy involving industry (Finardi). Finally, internal boundary layer modelling was carried out for the west coast of Denmark, with a view towards improving the parameterizations associated with air mass modification during on-shore flow (Dunkerley, et al).

	See also...
	CAPMAN Annnual Report 2000: Entry page to all parts of the report