Statistical Characteristics of Precipitated Water Vapor, Optical Depth and Cloudiness in the Northern Part of Russia

Abstract

One of the most important tasks of studying seeing conditions of possible locations for the Eurasian Submillimeter Telescopes is to research the statistics of precipitated water vapor, optical depth and cloudiness. In this paper, the statistics of precipitated water vapor and total cloudiness in northern Eurasia are studied using ERA-5 reanalysis. Optical depth statistics at a wavelength of 3 mm were obtained using the Liebe model from the ERA-5 reanalysis for the region where the Large Altazimuth Telescope BTA is located. The most favorable astroclimatic zones of Eurasia, along with Tibet and the eastern Pamirs, are certain areas of the Sayan Mountains, mountainous Altai and mountainous Dagestan. The work verifies the ERA-5 reanalysis data using radiosounding, GNSS measurement data and radiometric measurements for 2021.