DOI: 10.6084/m9.figshare.10026563.v4
title: A high-quality hourly, daily and monthly solar irradiance dataset in China during 1981-2014 based on MERRA-2 Reanalysis productsed Item

description: <b>A high-quality hourly, daily and monthly solar irradiance dataset in China during 1981-2014</b><b> based on MERRA-2 Reanalysis products</b><br>Wenmin Qin<sup>1</sup>, Lunche Wang<sup>1</sup>, Ming Zhang<sup>1</sup>, Lan Feng<sup>1</sup>, Yulong Zhong<sup>1</sup>, Qiqi Zhu<sup>1</sup>，Hejin Fang<sup>1</sup>, Hong Cai<sup>1</sup>, Chao Yang<sup>2</sup><sup>1</sup>Hubei Key Laboratory of Critical Zone Evolution, School of Geography and Information Engineering, China University of Geosciences, Wuhan 430074, China;<sup>2</sup> Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China;Corresponding author: Wenmin Qin, Hubei Key Laboratory of Critical Zone Evolution, School of Geography and Information Engineering, China University of Geosciences, Lumo road 388, Hongshan District, Wuhan 430074, China; E-mail: qinwenmin@cug.edu.cn.<b>Abstract: </b>Solar irradiance (SI) is the main driving factor contributing to climate change and energy balance between the land and atmosphere. High-quality records of global solar irradiance (GHI), direct normal irradiance (DNI) and diffuse solar irradiance (DIF) are of vital importance for solar applications, but the solar radiation observations are sparse around the world. As an alternative, numerous SI reanalysis data in grid format have been developed in regional and global scales. Among them, the MERRA-2 (Modern-Era Retrospective Analysis for Research and Applications, version 2) products could provide high quality SI records with acceptable accuracy and long temporal ranges. This study attempted to improve the accuracy of GHI records derived from MERRA-2 products, and to generate grid DNI and DIF datasets for all-sky conditions over mainland China during 1981-2014, based on the REST2 model and cloud transmittance estimates combining sunshine observations. The results indicate that the estimated GHI values (GHInew) show higher agreements with GHI measurement at 17 CMA (China meteorological administrations) stations than that for the GHI records derived from MERRA-2 products (MERRA-2 GHI). Then, grid GHI, DNI and DIF datasets (0.50° (lat) *0.625° (lon)) throughout China were constructed. The results indicated that the MERRA-2 GHI records may overestimate the GHI values over mainland China. The grid GHI, DNI and DIF dataset generated in this study can assist in numerous solar studies and applications.<br><br>Due to the limitation of data upload quantity and speed, we only upload 10 netcdf files, and pack all the remaining netcdf files into a compressed file, the file name of the compressed file is SWGDN.rar. We apologise that the hourly solar irradiance data was not uploaded, because the data size of hourly solar irradiance data is too big (nearly 13Gb). The hourly and monthly solar irradiance data could be obtain by email (qinwenmin@cug.edu.cn).<br><br>Please cite this article: Qin, W., Wang, L., Zhang, M., Feng, L., Fang, H., Cai, H., Zhong, Y., Zhu, Q., and Yang, C.: A high-quality hourly, daily and monthly solar irradiance dataset in China during 1981–2014 based on MERRA-2 Reanalysis products, Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2019-204, in review, 2019.<br>