Estimation of snowfall, maximum snow depth and snow cover condition in Japan under global climate change.

Abstract

Global environmental change is expected to have a major impact on Japan's winter climate and snowfall. Therefore, based on a global environmental change scenario that is the result of a numerical experiment using a general circulation model, we predicted changes in snowfall conditions.The method uses monthly average temperature and monthly precipitation as input, predicts monthly snowfall depth using an empirical model, and statistically calculates the deepest snowfall from the obtained snowfall depth and temperature. This method predicts snow quality. Using this method, we estimated changes in snowfall conditions over time from now to 100 years from now, and regional characteristics became clear. Hokkaido and Honshu mountain regions in the Tohoku region, excluding mountainous regions, there was no significant change in snowfall conditions except for a decrease in the deepest snowfall. In the Tohoku region, excluding mountainous areas, there was a large change in snowfall depth and deepest snowfall, and a change from dry snow to wet snow. In the plains on the Japan Sea coast south of the Hokuriku region, rising temperatures have caused snow to no longer fall or accumulate.These characteristics have become especially noticeable after 50 years.In addition, three other global environmental changes have occurred. The scenario also predicted a transition to the same snowfall situation.The interannual variation in snowfall depth was predicted to increase in the northern Tohoku region and Hokkaido after 51 to 75 years. ​