The Response of Vegetation Cover in the West Siberian Plain to Climate Changes in 1982-2015

This paper is devoted to studying the response of different types of vegetation cover in the West Siberian Plain to temperature changes observed in recent decades. The paper analyzes trends in the series of the normalized difference vegetation index (NDVI) and air temperature in the vicinities of meteorological stations of the West Siberian Plain, which are characterized by different types of vegetation. Phases of growth (1982-1997) and stabilization (1997-2015) of NDVI values have been revealed against the background of the observed effects of global-warming slowdown, decrease of solar activity, and transition from the positive phase of the ocean-surface temperature to the negative phase in the El Nino region (ONI). It is shown that the spring months make the main contribution to variations in the seasonal NDVI value. A correlation analysis of spring NDVI and air-temperature values during the periods of NDVI growth and stabilization has been carried out. It is shown that the pattern of response of vegetation to the observed increase in temperature depends on its type and location. Thus, the relationship between the NDVI and air temperature increases in the tundra zone, decreases in very swampy areas of forest tundra and northern taiga, generally decreases in the Ob-Yenisei interfluve from forest tundra to subtaiga, and increases on the left bank of the Ob River.