Published online in Wiley InterScience (www.interscience.wiley.com) DOI:10.1002/joc.1382 SNOW DISAPPEARANCE IN EASTERN SIBERIA AND ITS RELATIONSHIP TO ATMOSPHERIC INFLUENCES

• Main Authors: Yoshihiro Iijima, Kooiti Masudab, Tetsuo Ohataa
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2006
• Subjects: lena river; Siberia
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.569.9657; http://www.jamstec.go.jp/seika/pub-j/res/ress/yiijima/pdfs/Iijima2007IJC.pdf

In the present study, we examine the climatological features and interannual variations in snow disappearance within the Lena River Basin, Eastern Siberia, during a recent 15-year period (1986–2000), and the relationship of snow disappearance to atmospheric conditions. According to the climatology of the day of the year on which snow disappears, the boundary of snow disappearance within the Lena River Basin migrates rapidly northward from mid-April until early June, with minimum interannual variation occurring in the middle part of the basin. In addition, the preceding snow disappearance is apparent in the central Lena River Basin. Melting of snow within the Lena River Basin commonly occurs within 30 days of complete snow disappearance under certain atmospheric conditions: daily mean air temperature in excess of −10 °C, greater than 2 hPa of water vapor pressure, and, hence, more than 170 W m−2 of downward longwave radiation under clear sky conditions. Composite analysis using a reanalysis dataset demonstrates that the increase in air temperature and water vapor that accompanies snow melting is due to wet (and warm) air advection in conjunction with enhanced water vapor convergence over the central Lena River Basin during the 30-day period prior to snow disappearance. Copyright 2006 Royal Meteorological Society. KEY WORDS: Eastern Siberia; snow disappearance; water vapor advection; downward longwave radiation