A daily sunshine duration (SD) dataset in China from Himawari AHI imagery (2016-2023)

Abstract

Monitoring global radiation resources relies on sunshine duration (SD) as an important indicator; however, research examining high-resolution SD data is scarce. This study established a daily 5 km SD dataset in China from 2016 to 2023 using Himawari's Advanced Himawari Imager (AHI) Level 3 shortwave radiation fitted with the Ångström-Prescott model based on a time series. We used ground-measured SD at 2380 Chinese Meteorological Administration stations to verify the SD dataset accuracy. The results of the testing set indicate that the average correlation coefficient between the SD from the estimation and ground measurements was 0.88. Additionally, we investigated the effects of wind speed, vapour pressure, precipitation, aerosol optical depth, and cloud capacity on the estimation performance of SD and found that temperature had the greatest effect. We also found that cloud capacity that was both too low and too high, and wind speed that was too high affected SD estimation on an average annual scale. These high-resolution SD data provide important support for accurate radiation resource assessments in China. The SD dataset is freely accessible at 10.57760/sciencedb.10276 (Zhang et al., 2024).