Reconstruction Of Global Solar Radiation In Japan From Dairy Weather Records For The Period 1720-1902

Global solar radiation during the Little Ice Age, especially for the period 1720-1902, is estimated based on the daily weather records of old diaries in Japan. This study develops and constructs a method for estimating global solar radiation from daily weather records. Many documents dating from 17th century contain records of daily weather conditions in Japan. Ichino et al. (2001, Tenki) developed a method for estimating monthly mean solar radiation from daily weather descriptions. Then the weather records of a modern weather service (Japan Meteorological Agency) were used. In the present study, we improve the method taking account for the difference in weather descriptions between diaries and records of modern weather services. To estimate global solar radiation from historical weather condition records, this study improve the method. Global solar radiation for the period 1720-1902 in Tokyo and for 30 years included the 1830s at several points in Japan using the daily weather records of the old diaries is estimated based on the improved method.