Increase of surface solar irradiance across East China related to changes in aerosol properties during the past decade

Previously, it was widely documented that an overall decrease in surface solar radiation occurred in China at least until 2005, in contrast to the general background of 'global brightening'. Increased anthropogenic aerosol emissions were speculated to be the source of the reduction. In this study, we extend the trend analysis to the most recent decade from 2005–2015 and find that surface solar radiation has shifted from 'dimming' to 'brightening' over East China, with the largest increase over the northeast and southeast parts. Meanwhile, satellite and ground observation both indicate a reduction in aerosol optical depth (AOD) during the same period, whereas no significant trends in cloud amount show up. Detailed analysis using co-located radiation and aerosol observation at the XiangHe station in North China suggests that both AOD and single scattering albedo (SSA) changes contribute to the radiation trends. AOD reduction contributes to the increase of direct solar radiation, also decreasing the diffuse radiation, while the increase of SSA serves to increase the diffuse fraction. Simple calculations using a radiative transfer model confirm that the two effects combined explain changes in the global solar radiation and its components effectively. Our results have implications for potential climate effects with the reduction of China's aerosol emissions, and the necessity to monitor aerosol composition in addition to its loading.

[1]  E. Mlawer,et al.  Radiative transfer for inhomogeneous atmospheres: RRTM, a validated correlated-k model for the longwave , 1997 .

[2]  L. Remer,et al.  The Collection 6 MODIS aerosol products over land and ocean , 2013 .

[3]  P. Jones,et al.  Updated high‐resolution grids of monthly climatic observations – the CRU TS3.10 Dataset , 2014 .

[4]  X. Y. Zhang,et al.  Analysis of 40 years of solar radiation data from China, 1961–2000 , 2005 .

[5]  Martin Wild,et al.  Trends in aerosol radiative effects over China and Japan inferred from observed cloud cover, solar “dimming,” and solar “brightening” , 2009 .

[6]  Kebin He,et al.  Global climate forcing of aerosols embodied in international trade , 2016 .

[7]  Chunsheng Zhao,et al.  Changes in surface aerosol extinction trends over China during 1980–2013 inferred from quality‐controlled visibility data , 2016 .

[8]  P. Sen.  Estimates of the Regression Coefficient Based on Kendall's Tau , 1968 .

[9]  T. Eck,et al.  Accuracy assessments of aerosol optical properties retrieved from Aerosol Robotic Network (AERONET) Sun and sky radiance measurements , 2000 .

[10]  A. Ohmura,et al.  The Global Energy Balance Archive , 1999 .

[11]  Bernard Pinty,et al.  Determination of land and ocean reflective, radiative, and biophysical properties using multiangle imaging , 1998, IEEE Trans. Geosci. Remote. Sens..

[12]  Yang Wang,et al.  Distinct impact of different types of aerosols on surface solar radiation in China , 2016 .

[13]  M. Roderick,et al.  The cause of decreased pan evaporation over the past 50 years. , 2002, Science.

[14]  C. Long,et al.  From Dimming to Brightening: Decadal Changes in Solar Radiation at Earth's Surface , 2005, Science.

[15]  Kebin He,et al.  Recent large reduction in sulfur dioxide emissions from Chinese power plants observed by the Ozone Monitoring Instrument , 2010 .

[16]  Xiangao Xia,et al.  Ground-based remote sensing of aerosol climatology in China: Aerosol optical properties, direct radiative effect and its parameterization , 2016 .

[17]  David G. Streets,et al.  Aura OMI observations of regional SO2 and NO2 pollution changes from 2005 to 2015 , 2015 .

[18]  Beat Schmid,et al.  Sensitivity of shortwave radiative flux density, forcing, and heating rate to the aerosol vertical profile , 2010 .

[19]  Jun Bi,et al.  More efforts, more benefits: Air pollutant control of coal-fired power plants in China , 2015 .

[20]  D. Streets,et al.  Satellite NO2 retrievals suggest China has exceeded its NOx reduction goals from the twelfth Five-Year Plan , 2016, Scientific Reports.

[21]  Oleg Dubovik,et al.  Recent trends in aerosol optical properties derived from AERONET measurements , 2014 .

[22]  X. Xia,et al.  Comparison of column-integrated aerosol optical and physical properties in an urban and suburban site on the North China Plain , 2015, Advances in Atmospheric Sciences.

[23]  Martin Wild,et al.  Impact of global dimming and brightening on global warming , 2007 .

[24]  Biao Wang,et al.  Data Quality Assessment and the Long-Term Trend of Ground Solar Radiation in China , 2008 .

[25]  J. Hansen,et al.  Large historical changes of fossil‐fuel black carbon aerosols , 2003 .

[26]  Sheng Yue,et al.  The influence of autocorrelation on the ability to detect trend in hydrological series , 2002 .

[27]  T. Eck,et al.  Wavelength dependence of the optical depth of biomass burning, urban, and desert dust aerosols , 1999 .

[28]  Steven A. Ackerman,et al.  Cloud Detection with MODIS. Part II: Validation , 2008 .

[29]  Zhanqing Li,et al.  Estimation of aerosol effects on surface irradiance based on measurements and radiative transfer model simulations in northern China , 2007 .

[30]  A. Smirnov,et al.  AERONET-a federated instrument network and data archive for aerosol Characterization , 1998 .

[31]  M. Kendall,et al.  Rank Correlation Methods , 1949 .

[32]  Y. Qian,et al.  Variability of solar radiation under cloud‐free skies in China: The role of aerosols , 2007 .

[33]  Martin Wild,et al.  Trends in aerosol radiative effects over Europe inferred from observed cloud cover, solar “dimming,” and solar “brightening” , 2007 .

[34]  K. Stamnes,et al.  Numerically stable algorithm for discrete-ordinate-method radiative transfer in multiple scattering and emitting layered media. , 1988, Applied optics.

[35]  Zhanqing Li,et al.  Distinct weekly cycles of thunderstorms and a potential connection with aerosol type in China , 2016 .

[36]  Bernard Pinty,et al.  Techniques for the retrieval of aerosol properties over land and ocean using multiangle imaging , 1998, IEEE Trans. Geosci. Remote. Sens..

[37]  Jie He,et al.  Solar radiation trend across China in recent decades: a revisit with quality-controlled data , 2010 .

[38]  Shepard A. Clough,et al.  Atmospheric radiative transfer modeling: a summary of the AER codes , 2005 .

[39]  H. B. Mann.  Nonparametric Tests Against Trend , 1945 .

[40]  Gert König-Langlo,et al.  Global dimming and brightening: An update beyond 2000 , 2009 .

[41]  Michael J. Garay,et al.  Satellite-derived aerosol optical depth over dark water from MISR and MODIS : Comparisons with AERONET and implications for climatological studies , 2007 .

[42]  B. McArthur,et al.  Baseline surface radiation network (BSRN/WCRP) New precision radiometry for climate research , 1998 .

[43]  Xiangao Xia,et al.  Long-term trends in solar radiation and the associated climatic factors over China for 1961-2000 , 2005 .

[44]  V. Ramanathan,et al.  Aerosols, Climate, and the Hydrological Cycle , 2001, Science.