Impact of the Scandinavia and East Atlantic/Western Russia Patterns on Wind Stress Curl over the Black Sea

The impact of two global climatic oscillating modes, East Atlantic/Western Russia (EA/WR) and Scandinavia (SCA) patterns, which significantly affect the climate in the Atlantic-Eurasian sector, on wind stress curl (WSC) over the Black Sea is studied. The wind data from the MERRA-2 reanalysis and the series of the SCA and EA/WR indices for 1980–2019 are used. The composite method was applied taking into account nonstationarity of the time series of the indices, and the spectral analysis is used for the stationary series. There is a significant increase in cyclonic WSC in different parts of the sea for most of a year during the positive phase of SCA. In September and October and on average in winter, the positive phase of EA/WR is accompanied by a significant increase in anticyclonic WSC. In general, it has been found that SCA influences the formation of the spatiotemporal structure of WSC more strongly than EA/WR.