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Wind velocity data obtained from in situ measurements at the Golitsyno 4 marine stationary plat form have been compared with QuikSCAT scatterometer data; NCEP, MERRA, and ERA Interim global reanalyses and MM5 regional atmospheric reanalysis. In order to adjust wind velocity measured at a height of 37 m above the sea surface to a standard height of 10 m with stratification taken into account, the Monin-Obukhov theory and regional atmospheric reanalysis data are used. Data obtained with the QuikSCAT scatter ometer most adequately describe the real variability of wind over the Black Sea. Errors in reanalysis data are not high either: the regression coefficient varies from 0.98 to 1.06, the rms deviation of the velocity amplitude varies from 1.90 to 2.24 m/s, and the rms deviation of the direction angle varies from 26° to 36°. Errors in determining the velocity and direction of wind depend on its amplitude: under weak winds (<3 m/s), the velocity of wind is overestimated and errors significantly increase in determining its direction; under strong winds (>12 m/s), its velocity is underestimated. The influence of these errors on both spatial and temporal estimates of the charac teristics of wind over the Black Sea is briefly considered.

The statistically ensured estimates of characteristics of temporal variability of wind speed and wind direction are obtained on the basis of observations carried out in 1996-2001 at the offshore fixed platform in the northwestern part of the Black Sea. The maximum values of monthly mean wind speed (more than 8 m/s) are registered in the cold half-year and the minimum ones (~4 m/s), in summer. The moderate winds of northern and southern directions dominate during the whole year. Using the Pearson's chi-squared test, it is demonstrated that the wind speed follows the normal distribution law during the most part of observation period. The largest deviations from the normal law are timed to the periods of existence of intensive large-scale anomalies in the ocean-atmosphere system. A significant alternation of both synoptic and lower-frequency intramonthly wind speed fluctuations with typical periods of~10-15 days is revealed. Their peak amplitude was registered in the fall and winter season of 1997/98, i.e., it was observed during the mature phase of one of the most intensive El Niños during the whole period of instrumental observations. At that time, the energy of intramonthly low-frequency wind speed fluctuations (~4 m 2 /s 2 ) was equal to the energy of fluctuations within the synoptic range of the spectrum.

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