Hydro-Climatological Study on Snow and Ice of the East Asia

日本冬季气候的特点是日本海一侧的地区降雪量大，太平洋一侧的天气晴朗。与日本北方沿海的大雪相比，亚洲大陆东北部气候相对干燥，积雪不深，日本冬季气候受亚洲大陆气候控制，但亚洲大陆各国水文气候资料不足。研究的第一步是编辑冰雪地图。收集了日本、中国、朝鲜和苏联公布的数据，用几张气候图编辑了关于最大积雪深度、积雪持续时间和冰的南部界限的地图。对日本北方几个站的雪和融雪水进行了化学分析。根据古日记和文献资料，分析了古雪灾的主要来源，认为古雪灾的主要来源是融化季节前土壤中储存的古水，并对古雪灾的冬季气候进行了研究，结果表明：（1）小冰期的冬季比现在寒冷，（2）小冰期的冬季比现在寒冷;（2）寒冷的冬天没有持续多年;（3）日本与亚洲大陆气候关系的研究被认为是了解我们的自然环境的最重要的问题。条件这项研究提供了这一研究领域的基本数据。

Winter climate of Japan is characterized by heavy snowfall in the region on the Japan Sea side and sunny days on the Pacific side. As compared with heavy snow in the northern coast of Japan, climate of the north-east part of the Asian continent is relatively dry and snow-cover is not deep.Winter climate of Japan is controlled by that of the Asian continent, but information on hydroclimate of the countries of the continent is not sufficient. The first step of the study was to edit the map of snow and ice. Published data on Japan, China, Korea and USSR were collected and maps on maximum snow-depth, duration of snow cover and southern limit of ice were edited with several climatic maps. The distribution is explained climatologically.Chemical analysis of snow and snow-melt water wes made in several station in northern Japan. It was noted that main source of snow melt flood came from old water which had been stored in the soil before the melting season.Winter climate during the past ages was also investigated basing on old diaries and documents.The analysis revealed that, (1) winter was colder than the present in the Little Ice Age, (2) cold winter was not continued for many years and (3) coldness in Japan and China was not closely correlated.The research on the relationship of climate between Japan and Asian continent is regarded to be the most important in understanding our physical condition. The study gives fundamental data on this field of study.