Total Content of Water Vapor Over Yamal During the Warm Period of the Year

Abstract

The spatial distribution of total water vapor content over the Yamal Peninsula and adjacent territories was analyzed using data of four-year-long measurements from the European Envisat satellite during warm periods of the year (June-August). Special attention was given to water vapor variations at the transition from little to abundant water-bearing areas of the underlying surface. It was found that for the five selected sites located in a dry tundra and in large water bodies the logarithmic rather than Gaussian form of the distribution functions of total water vapor content turned out to be typical according to the number of its measurements. Each function has at least two modes. The parameters of these modes were calculated and presented, and they are necessary for simulation of climatic conditions in the northern territories. Geometric mean values of total water vapor content over the Gulfs of Gydan and Baidaratsk, and especially over the Gulf of Ob, can be by a factor of 1.5 larger than those for the less water-abundant areas of tundra and have clear boundaries coincident with geographical contours of the water bodies. It is most likely that these boundaries exist at insignificant speeds of surface winds, which is indicative of weak turbulent mixing of the lower air layers. This conclusion is confirmed by results from processing published data of ground-based and satellite observations. For the five sites they were used to calculate and construct the wind roses for all five sections in the same time intervals when the satellite measurements of water vapor content were carried out. Wind rose analysis shows that the average velocity of predominantly N and NW winds on all the selected sites at a height of 10 m above the underlying surface are 5–6 m/s with a standard deviation of 1.5 m/s. Additional data are presented on the form of the distribution function of various parameters in other natural environments (water bodies and vegetation) which give support to what has been said above about water vapor.