Operational forecast of hydrophysical fields in the Georgian Black Sea coastal zone within the ECOOP

Abstract. One of the parts of the Black Sea Nowcasting/Forecasting System is the regional forecasting system for the easternmost part of the Black Sea (including the Georgian water area), which has been developed within the context of the EU International projects ARENA and ECOOP. A core of the regional system is a high-resolution baroclinic regional model of the Black Sea dynamics developed at M. Nodia Institute of Geophysics (RM-IG). This model is nested in the basin-scale model of Marine Hydrophysical Institute (MHI, Sevastopol/Ukraine). The regional area is limited to the Caucasian and Turkish coastal lines and the western liquid boundary coinciding with the meridian 39.36° E. Since June 2010 we have regularly been computing 3 days' forecasts of current, temperature and salinity for the easternmost part of the Black Sea with 1 km spacing. In this study the results of two forecasts are presented. The first forecast corresponds to summer season and covers the prognostic interval from 00:00 h, 6 August to 00:00 h, 9 August 2010. The second one corresponds to autumn season and covers the prognostic interval from 00:00 h, 26 October to 00:00 h, 29 October 2010. Data needed for the forecasts – the initial and prognostic hydrophysical fields on the open boundary, also 2-D prognostic meteorological fields at the sea surface – wind stress, heat fluxes, evaporation and precipitation rates for our regional area are being placed on the MHI server every day and we are available to use these data operatively. Prognostic hydrophysical fields are results of forecast by the basin-scale model of MHI and 2-D meteorological boundary fields represent the results of forecast by regional atmospheric model ALADIN. All these fields are given on the grid of basin-scale model with 5 km spacing and with one-hour time step frequency for the integration period. The analysis of predicted fields shows that to use the model with high resolution is very important factor for identification of nearshore eddies of small sizes. It should be noted the very different character of regional circulation in summer and autumn seasons in the easternmost part of the Black Sea.