One equation integral models are often used for describing snow avalanches, but because of the lack of data there is no agreement on the appropriate drag forces and coefficients or the significance of slope curvature effects. This paper describes ping-pong ball avalanche experiments that were carried out at a ski jump in Japan. The front of the avalanche was measured using video cameras and the data used to test simple integral models with and without curvature. The scaling of the basal-friction and air drag coefficients was examined.
The principle conclusions of this analysis are as follows: A one equation model with velocity squared air-drag and velocity independent basal-friction well describes the data. The effect of slope curvature is not important. The air-drag coefficient is specified by an inverse length scale 1/L, where L scales as N^1/3, and n is the number of balls. The basal-friction coefficient is constant between experiments.

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The Concept of the SEAGUL system (Snow Enhancing Atomic-power Generation UtiLity) is proposed in this paper. Lowering the temperature of sea water used for cooling an atomic-power plant will increase the a efficiency of power generation and add several ten MW additional electric power to the output of a 1356 MW class plant. The system concept is to use a huge amount of seasonal storage snow for cooling water temperature control. In a case study for the Kashiwazaki-Kariwa Nuclear Power Generation Plant, it is estimated that cooling down the sea water from 29 C to 20 C using 80 kt of snow for 3 hours in a day would add 60 MWh of electric power per day. Annually, 3.4 Mt of stored snow will add 1800 MWh of electric power.

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Long-term risk trend analysis for snow-related casualty cases in Niigata Prefecture for 46 winter seasons was carried out. Specifically risk and factor analysis of 1037 records of casualty cases in the most recent 16 winter seasons was conducted. The results are summarized as follows:
1. After the 1985-86 severe snowfall winter season, even though warm and snow-scarcity winter continued, the risk of snow-related casualty cases increased. On average, 127 persons suffer accidents, 16 of them fatal, in a winter.
2. After 1987, it could not find low frequency and high magnitude risk of fatal cases. but high frequency and low magnitude risk of injury cases is increased.
3. Casualty cases are classified into 7 categories: tumbling down from a height (64%), accidents involving rotary snow-plow operation (15%), falling snow/objects (11%) and so on. High fatality rates appear in the categories of falling into waterways and coming down with a disease, and to 70 years or older persons, and in the time between 19 pm and 21 pm.
4. 97 percent of casualty cases occurred in the area where 43% of the population lives. Especially, the personal risk rate in the mountainous snowy region is 1.8×10^-5 person/yr.
5.The risk rate associated with meteorological conditions at the day becomes higher by lower temperature, and is particularly high when there is more than 1 meter snowfall rate for 3 days or 1.5 meters 7 days.
6.Comparing the 1980's and 1990's, the number of injuries to aged persons and younger persons is on the rise.
7.The risk of snow-related fatal accidents in the mountainous snowy region is almost equivalent to that of traffic accidents and 16 times that of occupational fatal cases.

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We suggest a procedure selecting the optimum size of narrow snowbreak woods. The procedure involves examining the following items in this order:
1) Snowbreak effect in relation to planting conditions and tree height
2) Setting of quantitative targets for controlling blowing snow
3) Calculation of cumulative frequencies of visibility and wind velocity
4) Conditions for installation of narrow snowbreak woods
We demonstrate that the conditions for effective installation of narrow snowbreak woods can be determined through knowledge of the maximum wind velocity and the frequency of poor visibility (less than 200 m) in the survey area.

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