Trends in downward surface shortwave radiation from multi‐source data over China during 1984–2015

Abstract

The clear knowledge of decadal variability of surface solar radiation (SSR) is of vitally significant for understanding hydrological and biological processes and climate prediction. However, existing studies have shown observed SSR over China may have large discrepancies and inhomogeneity in decadal variability due to sensitivity drift, inaccurate calibrations and instrument replacement. Therefore, a new procedure of station selection was proposed to eliminate errors and to derive “true” SSR values in this study. Afterward, two satellite retrieves of SSR, including Clouds and the Earth's Radiant Energy System‐energy balanced and filled product (CERES‐EBAF) (edition 4) and Global Energy and Water Cycle Experiment‐Surface Radiation Budget (GEWEX‐SRB) (Version 3.0), and three reanalysis products, including National Centers for Environmental Prediction‐National Center for Atmospheric Research (NCEP‐NCAR), national centers for environmental prediction‐/department of energy (NCEP‐DOE) and Modern‐Era Retrospective analysis for Research and Applications, version 2 (MERRA‐2) were evaluated using “true” SSR values at 39 homogeneous stations from the China Meteorological Administration and it was found that although all five products overestimated SSR, two satellite retrieves showed better accuracy with an overall R of 0.95, an root mean squared error (RMSE) of 20.4 W m−2 and mean absolute bias error (MAE) of 14.9 W m−2 for CERES‐EBAF and an overall R of 0.92, an RMSE of 27.7 W m−2 and MAE of 21.2 W m−2 for GEWEX‐SRB across China. Meanwhile, inter‐comparisons between trends of observations and trends of two satellite retrieves in this study showed that the new trends derived from two satellite retrieves (+0.78 W m−2 decade−1) were good agreement with trends of observation (+0.92 W m−2 decade−1) from 1994 to 2015. However, trends of SSR (+5.8 W m−2 decade−1) in situ measurements were still in disagreement with the trends of SSR (−3.7 W m−2 decade−1) derived from two satellite retrieves from 1984 to 1993 because of the sensitivity drift and instrument replacement in this period. The possible reasons for decadal variability of SSR in China were detected and it was found that variations in aerosol optical depth (AOD) and aerosol‐cloud interaction, rather than cloud, were suggested to be likely the main influencing factor of decadal variability of SSR across China from 1984 to 2015.

Northern dimming and southern brightening in eastern China during the first decade of the 21st century

“…Noticeably, the nationwide averaged GSR anomalies (averaged over 119 stations in China) experienced a stable period from 2000 until 2010. This is largely in agreement with the result from Yang et al (2019) and Zhou et al (2019). The result shows that the GSR anomalies experienced the opposite trends in NR and SR during the leveling-off period (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010), mainly for the summer.…”

“…Some results have indicated the brightening in recent years in China (Yang et al, 2019). In terms of the studies of GSR trend analysis in China, many preceding researches have presented the long-term changes in GSR at different temporal-spatial scales (e.g., Che et al, 2005;Tang et al, 2011;Zhou et al, 2019). Some researchers have further compared regional differences in the variabilities of GSR between different areas in China.…”

Hourly Surface Observations Suggest Stronger Solar Dimming and Brightening at Sunrise and Sunset Over China

“…Despite the complex causes for global dimming and brightening (Stanhill & Cohen, 2001; Wild, 2009), anthropogenic aerosols have been increasingly proposed as the dominant factor regulating the decadal trends of SSR in China (e.g., Wang et al., 2020; Yang et al., 2019; Zhou et al., 2020). On the diurnal scale, the extinction of light by aerosols is determined not only by the changing concentrations of aerosols in the atmosphere but also the changing position of the sun through the day (Spokas & Forcella, 2006).…”

“…Basically, aerosols can scatter and absorb SSR depending on the nature of their composition (direct radiative forcing), or alter cloud radiative properties and lifetimes due to their role in the formation of cloud condensation nuclei (indirect radiative forcing) (Ramanathan et al, 2001;Wild, 2009). Despite the complex causes for global dimming and brightening (Stanhill & Cohen, 2001;Wild, 2009), anthropogenic aerosols have been increasingly proposed as the dominant factor regulating the decadal trends of SSR in China (e.g., Wang et al, 2020;Yang et al, 2019;Zhou et al, 2020). On the diurnal scale, the extinction of light by aerosols is determined not only by the changing concentrations of aerosols in the atmosphere but also the changing position of the sun through the day (Spokas & Forcella, 2006).…”

Merging ground-based sunshine duration with satellite cloud and aerosol data to produce high resolution long-term surface solar radiation over China

“…Changes in aerosol loading have also been reported to be an important impact factor (Che et al, 2005;Li et al, 2018; Liang and Xia, 2005;Qian et al, 2015;Xia, 2010;Z. Zhou et al, 2019).…”