Knowledge of the Baltic Sea physics gained during the BALTEX and related programmes

Review is given about the main results of the oceanographic component of the BALTEX research programme (one of the six continental scale experiments within GEWEX-WCRP to study water and energy cycles in the regional climate system) and related programmes/projects over the last 10 years. Working closely together with two other components – regional meteorology and hydrology of the Baltic Sea drainage basin – oceanographic research has considerably improved the understanding of and ability to model the Baltic Sea marine system. In the Baltic Sea physics seven different broad topics are identified where knowledge has significantly improved. These are reviewed together with a discussion of gaps in knowledge. The focus is on the water and energy cycles of the Baltic Sea, but various aspects of forcing and validation data and modelling are also discussed. The major advances achieved through BALTEX and related programmes are:• ological, hydrological, ocean and ice data are now available for the research community. ss in understanding of the strong impact of large-scale atmospheric circulation on Baltic Sea circulation, water mass exchange, sea ice evolution, and changes in the ocean conditions of the Baltic Sea. ss in understanding of the importance of strait flows in the exchange of water into and within the Baltic Sea. ss in understanding of intra-basin processes. models introduced into Baltic Sea water and energy studies. pment of turbulence models and 3D ocean circulation models for application to the Baltic Sea. ed Baltic Sea ice modelling and increased understanding of the need for coupled atmosphere–ice–ocean-land models.