Upwelling nearby the Crimea Western Coast

In connection with the problem of the seawater self-purification, the upwelling phenomenon nearby the Crimea western coast is considered in the present article. The observation data on wind and water temperature obtained at the Yevpatoria and Chernomorskoe weather stations as well as the sea surface temperature data derived by the NOAA-15/19 and MetOp-2 satellites were analyzed. 212 cases of upwelling are identified for the period from 1921 to 2011; most of them fall on July. In the majority of cases, the upwelling duration varied within 2-15 days, but in 20% of all the cases it lasted 16-30 days. On average, the duration comprised 11.8 days. The average rate of temperature variation in 75% of the cases observed did not exceed 0.1 degrees C/h. The anomalies exceeding 7 degrees C/h were observed in 18% of the cases; among them there are a few ones worthy of being noted when the temperature dropped by more than 11 degrees C (July, 1954 and 1996, and August, 2000). The available multi-year data on upwelling variability demonstrate neither expressed periodicity of the phenomenon nor long-term tendency to its decrease or increase. It is shown that the upwelling phenomenon in the Kalamitsky Bay is determined not only by the Ekman mechanism arising under the influence of the along-coastal wind, but also by the offshore wind effect resulting from the tangential wind stress.