The project is focussing on data assimilation, model development and To explore, model and quantify the various processes determining the space and time variability of the energy and water cycle of the Baltic Sea and diagnostic studies. its catchment area. To undertake specific assessments of the total flux divergence of heat, water and momentum for the region and determine its The project includes reanalysis for two specific periods representing a coupling to the large scale atmospheric circulation. The main emphasis is cold and a warm winter period, on the physical and dynamic processes of the coupled meteorological, respectively, as well as for a preliminary field experiment period in hydrological and oceanographic system with the development of better 1995 during which specific observations coupled regional models for the European region as a key objective. Such were collected. models will also constitute essential building blocks in biological and A high resolution data-assimilation system will be developed associated ecological studies of the Baltic Sea. with retrieval and calculation of atmospheric water vapor, cloud water and radiation fluxes. New types of observations, such as water vapor contents obtained from the Global Position System [GPS] will be used. High resolution regional climate models will be validated associated with improved physical parameterization of the hydrological cycle, including a better handling of snow related processes. A comprehensive hydrological model for the total river flow into the Baltic Sea will be developed. The data from such a model will be used to validate the hydrological cycle of the atmospheric models.