Variability of baroclinic rossby radius of deformation

In this study, we investigate variability of the first baroclinic Rossby radius (LR) of deformation for the Baltic Sea and the basin of the Mediterranean Sea. The baroclinic Rossby radius of deformation was calculated as the ratio of the phase speed of long linear internal waves of the lowest mode (which is the solution of the Sturm-Liouville problem for the vertical structure of the mode function and depends on the depth and stratification of the water density at the specific geographic location) and the Coriolis parameter. We use data from the GDEM V.3.0 climatology for the considered region. The seasonal and spatial variability of the baroclinic Rossby radius is discussed in detail. Its values for open areas do not exceed 10 km in the Baltic Sea, 20 km in the Black Sea and 15-18 km in the Mediterranean Sea. For the shelf zones of these seas, the values of LR are 2-3 times smaller. Seasonal differences are moderate, most pronounced in shallow areas, and can reach for most 5-9 km in the coastal regions of the Mediterranean Sea.