Long-term hindcast simulation of currents in the Baltic Sea

The dataset contains the results of numerical modelling of currents over a period of 50 years (1958-2007) in the Baltic Sea (Jędrasik and Kowalewski, 2019). A long-term hindcast simulation was performed using a three-dimensional hydrodynamic model PM3D (Kowalewski and Kowalewska-Kalkowska, 2017), a new version of the M3D model (Kowalewski, 1997).
The model is based on the Princeton Ocean Model (POM) developed at Princeton University (Blumberg and Mellor, 1987). Like POM, the M3D/PM3D model uses the Mellor-Yamada turbulence scheme and sigma vertical coordinates. The simulation was carried out in a rectangular grid of 3' (latitude) and 6' (longitude) resolution. The spatial resolution was 3 nautical miles, i.e. about 5.5 km. An open boundary was located between the Skagerrak and the Kattegat along the parallel connecting Skagen and Göteborg, where the water exchange with the North Sea takes place. A radiation condition based on Somerfield’s concept for velocities  vertically averaged and normal to the boarder  plane was applied. Atmospheric forcing for the period 1958-2007 was performed using the regional at amospheric climate model REMO (REgional MOdel) which was based on the numerical weather prediction model EM (Europa-Model) of the German Weather Forecast Service (DWD).
The eastward and northward components of surface currents and at a depth of 5 m, 10 m, 15 m, 20 m, 30 m,  40 m, 50 m and 60 m m were recorded every three hours in the computational grid of the model in unproiected form: LatLong, WGS 84 (EPSG: 4326). Analysis of the Baltic Sea current data spanning five decades showed  a higher stability of subsurface current eddies relative to the stability of ephemeral surface currents (Jędrasik and Kowalewski, 2019).

Kowalewski M.;1997; A three-dimensional, hydrodynamic model of the Gulf of Gdańsk; Oceanol. Stud., 26 (4); 77–98
Kowalewski M., Kowalewska-Kalkowska H., 2017, Sensitivity of the Baltic Sea level prediction to spatial model resolution, Journal of Marine Systems 173, 101–113, http://dx.doi.org/10.1016/j.jmarsys.2017.05.001
Jędrasik J., Kowalewski M., 2019, Mean annual and seasonal circulation patterns and long-term variability of currents in the Baltic Sea, J. Mar. Syst., 193, 1-26, doi:10.1016/j.jmarsys.2018.12.011