Abstract:
With reference to clouds and the earth’s radiant energy system (CERES) dataset,simulation of historical surface downward shortwave and longwave radiation by Chinese earth system models from coupled model intercomparion project phase 6(CMIP6)were evaluated.Regions with high inter-model variability were also identified.The results show that Chinese models can capture the seasonal variations of the two surface radiation components in the northern hemisphere with high values in summer and low values in winter.Ensemble monthly means of two radiation components from Chinese models agree well with CERES counterparts over land,but bias low over ocean.Chinese models can also produce the decreased surface downward shortwave radiation and increased longwave radiation at interannual time scale.Averaged over values from 2001 to 2014,downward shortwave radiation from Chinese models is 3.3 W·m
-2and 3.0 W·m
-2lower than CERES dataset over ocean and land,respectively.Chinese models show similar downward longwave radiation to CERES dataset over ocean,but bias low by 1.3 W·m
-2 over land.Chinese models overestimate surface downward shortwave radiation around 30°latitudes,but underestimation is found in other latitudes,especially in tropics and north polar regions.Simulation bias in downward longwave radiation fluctuates with latitudes with large simulation bias around high mountains.Tropical forests and Antarctic oceans are noteworthy regions with extreme large inter-model variability for simulating downward shortwave radiation by Chinese models.Greenland,Tibet Plateau,Andes Mountains and Antarctic oceans are regions with extreme large inter-model variability for simulating downward longwave radiation by Chinese models.