Fedor D Iurov, Lomonosov Moscow State University, Faculty of Geography, Cryolithology and Glaciology, Moscow, Russia, Valery I Grebenets, Lomonosov Moscow State University, Geographical Faculty, Cryolithology and Glaciology, Moscow, Russia and Vasiliy Andreevich Tolmanov, Lomonosov Moscow State University, Geographical faculty, Cryolithology and Glaciology, Moscow, Russia