Systems of ice movement on Lake Lappajärvi, Finland

Ice and shore formations caused by the movement of lake ice were studied in Lappajärvi from the winter of 1971‑72 to that of 1975‑76. The formations are described and classified on the basis of surveys and transverse sections, and an attempt is made to determine the dependence of these movements and their effects upon meteorological, hydrological and geomorphological factors. The results enable two models of process‑response systems to be set up for thermal and wind‑induced movements of lake ice. The principal regulator of the extent of thermal movement proved to be the depth and heat conductivity of the snow cover, while the form and structure of the ice‑push lake ramparts is governed by the slope, material, frost depth and vegetation cover of the shore