Characteristics of the snow depth in 2020 and estimation of future changes based on the relationship between temperature and precipitation.

Abstract

 This study estimated the relationship between temperature and precipitation and snow depth based on observations by the Japan Meteorological Agency, and clarified the characteristics of low snow depth in the year 2020, which was among the lowest in many regions. Although 2020 was a low snowfall year, the trends in temperature and precipitation, which are considered to be the background, differed across regions. Hokkaido had a record low rainfall and Honshu had a record high temperature. This is consistent with the trend of correlation between temperature or precipitation and snow depth in each region. In addition, the frequency of occurrence of temperature and precipitation that was equivalent to those in lowest snow depth was estimated for the situation under 2°C and 4°C warming using large ensemble dataset. In particular, it was found that the frequency of temperature that is equivalent to the case of historical lowest snow depth may occur as often as once every one to two years under a 2°C warming.