Data sets of ice drift velocity, which were measured using coastal radar stations installed on the northeastern shelf of Sakhalin Island, were analyzed. Observations of spring 1992–1993 were used. The tidal component was subtracted from the initial data of ice drift to define components of drift connected with the wind influence. Spatial derivatives of drift velocities were estimated as differences of drift vectors in four points. Spatial derivatives were used for definition of divergence, rotation, velocity of compression and stretching of ice cover. Dependence of deformation parameters on velocity and direction of wind is complex, especially during periods, when the concentration of ice is high.
Development of oil and gas deposits on the northeastern shelf of Sakhalin Island is carried out in severe ice conditions. Significant values of drift velocity caused by the tide and wind influence are the distinctive feature of this area. (Shevchenko et al., 2001). Estimation of possible ice loads must take into account ice drift forecasting. The region of interest is characterized by predominant northwest and south-east winds (Zemtsova, 1968). Wind velocities often reach great values, especially when deep cyclones are passing over the investigated region. Accordingly, the velocity of wind drift and deformations of ice cover, induced by the wind, can reach significant values. The purpose of this paper is to analyse the deformation of ice cover in the coastal zone by analysing the unevenness of ice motion within zone of radar view, and using data of radar drift observations. Wind influence on deformation factors is the subject of interest. Measurements at Coastal Radar Stations (CRS) Hourly vector series of ice drift, were obtained at three coastal radar stations: Levenstern (54.1°N, 142.9°E), Odoptu (53.5°N, 143.1°E), and Komrvo (51.1°N, 143.6°E).