Precipitation Amount Separated by Precipitation Type Using Discriminating Temperature During Winter Season

Abstract

The discriminating temperature, which is applied to determine the precipitation type (snowfall or rainfall) corresponding to 50% occurrence probability, is obtained from climatic data (SDP). The monthly discriminating temperatures were determined for 15 climatic regions of Japan using station daily data. The values range from 1.1°C to 3.0°C. By the values and digital maps of daily temperature, the precipitaion types were judged daily for whole grid map of daily precipitaion. Finally were obtained the digital maps of monthly snowfall and rainfall. As a result, precipitation is observed mostly as the type of rainfall along the coast of Japan Sea more than generally expected. While in Hokkaido and in the mountain area of northern part of Japan, precipitation is observed mostly as snowfall in winter.