Reconstruction of solar radiation in Tokyo since 1720 based on historical weather records

Abstract

This study reconstructed the fluctuations of solar radiation from 1720 to 1912 in Tokyo using daily weather descriptions in the historical diaries. Here, we present a long-time series of solar radiation since 1720 in Tokyo. We did this by amalgamating the reconstructions, the estimates using the daily sunshine duration records from 1913 to 1960, and the observations of daily solar radiation since 1961. It provides insights into low and high solar radiation over the last 300 years.