The present paper describes a new snow gauge which was by utilization of an electric balance. The balance measures the weight of snowfall in a bucket every minute automatically and the weight is recorded for about 24 hours into a portable computer connected with it.
This weighing gauge can measure the amount of snowfall directly without any delay or error caused from melting or evaporation. The minimum detectable snowfall intensity of this gauge is 0.062 mm/hr when the weight increases by 0.1 g/min, with a bucket of 35 cm in diameter. The snow in the bucket is not affected by wind or blizzard, because the gauge is enclosed with a fence and double windbreaker nets. The efficiency of snowfall collection is almost unity in comparison with other points near the gauge.
This gauge has been used during two winter seasons at Sapporo. The time variation of snowfall intensity measured by this gauge is very sharply defined. Therefore fine structure of snow clouds can be estimated from this snowfall rate.

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Outdoor experiments have been carried out over several years as basic research for the study of creation and preservation of an artificial permafrost under the ground, by utilizing the coldness of air in the winter seasons.
Heat pipes were used for a heat exchange between the heat under ground and the open air. Throughout the year the measurements were kept of air temperature, inground temperature, and the surface temperature along the heat pipe, etc. The total quantity of heat exchanged by the heat pipe was calculated as 2×10⁸J/m/season. The data required for simulation by computer were obtained from an analysis of measured values. Freon R-22 and R-12 were used as working fluids, and their different cooling effects compared.
Also a fan was used instead of the heat pipe. The fan enforces ventilation between the heat underground and the above ground cold air, and effects the heat exchange.
These two methods of heat exchange are compared and discussed.

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With parameterizations of heat and water vapor transport in snow cover, it is found that the water vapor transport increases with decreasing density and increasing temperature of snow cover, indicating that speed of metamorphosis is fast for soft snow. Flow-down speed of melt water in snow cover is expressed in terms of liquid water content, size of snow particle, and density of snow cover.

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The mechanical behavior of frozen clay and sand beams was studied in pure bending tests under various strain rates, temperature conditions and NaCl concentrations. The deflection and resistive force caused by deflection of the specimen were measured. Strain rate increase, temperature decrease and NaCl concentration decrease changed the resistive force/deflection curve from a mixed linear and non-linear section to a linear one. The resistive force at the upper limit on the linear part of each frozen clay and sand sample was changed monotonically by experimental factors. On the other hand, the maximum resistive force on the curve did not change monotonically. This phenomenon was not observed in the uniaxial compression test of the same frozen sand.
Applicability of the elastic theory, which was commonly used for concrete or sea ice, was examined for frozen soil. From the measured strain distribution on the side of specimens and observation of crack formation, it was confirmed that this theory was not applicable for the maximum resistive force. Therefore flexural yield strength was defined from the upper limit of the linear part.

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