Roles of Eastern Siberian Mountain Ranges in Precipitation -Verkhoyansk, Dzhugdzhur and Stanovoy Mountain Ranges-

Abstract

Precipitation amounts of three Lena mountain ranges (Verkhoyansk, Dzhugdzhur and Stanovoy) were investigated using numerical simulations for three months. First, we examined the precipitation distribution in eastern Siberia using routine station data. A north−south precipitation gradient was found, with the greatest precipitation in a southern area, and 47% of precipitation occurring in June, July, and August.To isolate the roles of the three Lena mountain ranges in determining precipitation, especially the north−south precipitation gradient, we conducted mountain removal experiments to examine differences in precipitation from the results of a real topography experiment. Results show that the Verkhoyansk (northeast of the Lena Basin) and Dzhugdzhur Mountain Range (southeast) had a weak effect on the north−south precipitation gradient. It was caused by relatively low specific humidity for Verkhoyansk and low elevation for Dzhugdzhur mountain range. The Stanovoy mountain range (south) exhibited a strong effect with higher specific humidity and elevation. Thus Stanovoy mountain range has the most contribution to north−south precipitation gradient among three Lena mountain ranges.

Trend and interannual variation in summer precipitation in eastern Siberia in recent decades

“…Precipitation is less than 200 mm, except over the southern part of the domain. In eastern Siberia, the precipitation distribution is characterised by a large meridional gradient from south to north, partly due to the existence of mountains located around the southeastern part of the analysis domain (Yoshida et al , ). Westerly moisture flux vectors predominate over Siberia, and the area of moisture flux divergence extends zonally along 60°N.…”