The purposes of this paper are to forecast the annual maximum snow depth based on the height of mantis's egg sacks which were attached on the branches or leaves, and to examine the reliability statistically. But, the height of mantis's egg sacks do not show the depth directly. It is necessary to consider the natural features such as ground slope and height of tree.
Statistically efficient similarity was recognized between the forecasted snow depth based on the height of mantis's egg sacks and the actually observed annual maximum snow depth.

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In cold climate tunnels, icicles and sidewall ices grow at the lining surface, and frost heaves of rocks occur at the back of the lining. For a purpose of these frost damage and frost heave of the tunnel, an adiabatic icicle prevention work has been provided in many railway tunnels.
To design the icicle prevention work, it is desirable to estimate reasonably atmospheric condition at the outside of tunnel.
This paper deals with a statistical estimation method of the atmospheric condition such as yearly mean air temperature, yearly amplitude and daily amplitude, which are based on an exreme distribution analysis.

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Storage of snow and ice has been carried out from ancient times. In 19 centuries ice was transported in world wide. Storage house for ice was built in America, London, Livapoor and others. In Japan, ice was stored in underground already 700 A.D. In Meiji to Shyowa epoch, many storage houses of ice and snow, Himuro were built in Hokuriku and Tohoku Districts. In Nagaoka the snow of 7000 m3 in volume was collected that was named 'Yuki-nio'. In recent year, snow was noticed again as natural energy. Vegetables and grains were stored in snow. It is start to use snow for. air-conditioning as cooling heat sources.
The control of snow melting was experimentally examined. Five kind of snow mound in the volume 120 m3, were built on open ground and.the surface was covered by soil, chaff, chaff in bag, glass-wool, and foam and then covered with plastic sheet. The process of melting was examined. Snow vanished in August in the case of the cover with soil, September with glass-wool, and remained untill next January with chaff. The average air temperature was 10°C in April and 25°C in August.

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