Impact of land use/land cover change on changes in surface solar radiation in eastern China since the reform and opening up

Observational evidence of the impacts of land use/land cover change (LULCC) on changes in surface solar radiation (SSR) in eastern China (EC) during 1979–2008 are identified by using diurnal temperature range as a proxy of SSR and by using observation minus reanalysis approach to disentangle these effects. For the period 1979–2008, the impact of LULCC is shown as a reduction in SSR in most stations in EC, whereas SSR in the reanalysis data has increased at nearly every location. The competition of the dimming effect of LULCC with the brightening effect in the reanalysis results in an observed dipole pattern of SSR with slightly decreasing (increasing) trends in most stations north (south) of the Yangtze River and statistically significant decreasing trends in central EC. In terms of EC area mean, this competition has resulted in a slightly dimming trend in the observed SSR during 1979–2008, although a transition from an apparent dimming to a general leveling off near 1990 is identified. For the period 1990–2008, LULCC has significantly reduced SSR in central EC and southern China. This dimming effect of LULCC competes with the apparent brightening effect in the reanalysis to result in the general leveling off in the observed SSR in terms of EC area mean and a sandwich spatial pattern in the observed SSR in EC where parts of central EC show significant dimming. The impact of LULCC on the changes in SSR may be through both biogeophysical and biogeochemical processes.