资源环境科技发展态势分析平台

Observations and simulations have shown that the Tibetan Plateau (TP) plays an important role in the climate and weather of East Asia. Uncertainties in reanalysis data sets have been documented by comparing them with independent rawinsonde data, but the impacts of incorporating this data into a reanalysis data set on the dynamical and thermodynamical features over the TP have not been assessed. Observations from the recent Third Tibetan Plateau Atmospheric Scientific Experiment (TIPEX-III) can be used to evaluate the Eastern TP ERA-Interim reanalysis data set (ERA). In this study, the Barnes objective analysis scheme is used to incorporate the rawinsonde data into the ERA to acquire the gridded data (OBJ) for examining heat and moisture budgets. It is shown that the OBJ budget-estimated rainfall intensity is better correlated with the observations than the ERA budget-estimated rainfall intensity. The ERA overestimates weak rainfall but underestimates heavy rainfall. The incorporation of special rawinsonde into the OBJ impacts the dynamical and thermodynamical characteristics both spatially and temporally. The downward motion and cooling are enhanced over the rainless regions/periods, while the upward motion and heating are enhanced over the rainy regions/periods. The rawinsonde effect is stronger with the increasing rainfall intensity. The differences of spatial distributions and temporal variations in heating between the OBJ and ERA are primarily determined by the vertical advection terms in heat and moisture budgets. The OBJ-derived large-scale forcing is essential for cloud-resolving model simulations of TP cloud systems. The above conclusions can also be applied to the ERA5.