Measured and predicted values of water temperature and salinity with special focus on the surface layer

The Baltic is a stratified sea. The upper layer is under the influence of atmospheric and terrestial factors. The mechanisms of these external factors on the surficial and subsurface water layer are well recognised but the vertical exchange in the water body is still not sufficiently investigated. Field measurements at sea are time consuming and expensive. A model of the Baltic Sea distributed to and accessible by institutions investigating the Baltic Sea is advantageous because of easier exchange modelled data. The modelling, especially of the surface layer is important due to the fact that outside the coastal zone continuous measurements of physical parameters is difficult. The comparison between measured in situ and modelled data serves as a tool for the corrections to HIROMB resulting in better approximation of real phenomena occurring in the Baltic Sea. Temperature and salinity values obtained on board rlv Baltica during the POLRODEX'97 expetriment were compared with modelled values. The analysis showed significant differences between in situ measurements and obtained from the HIROMB model.