Abstract

Net precipitation [precipitation minus evapotranspiration (P -- E)] changes between 1979 and 2011 from a high-resolution regional climate simulation and its reanalysis forcing are analyzed over the Tibetan Plateau (TP) and compared to the Global Land Data Assimilation System (GLDAS) product. The ... Show moreNet precipitation [precipitation minus evapotranspiration (P -- E)] changes between 1979 and 2011 from a high-resolution regional climate simulation and its reanalysis forcing are analyzed over the Tibetan Plateau (TP) and compared to the Global Land Data Assimilation System (GLDAS) product. The high-resolution simulation better resolves precipitation changes than its coarse-resolution forcing, which contributes dominantly to the improved P--E change in the regional simulation compared to the global reanalysis. Hence, the former may provide better insights about the drivers of P -- E changes. The mechanism behind the P -- E changes is explored by decomposing the column integrated moisture flux convergence into thermodynamic, dynamic, and transient eddy components. High-resolution climate simulation improves the spatial pattern of P -- E changes over the best available global reanalysis. High-resolution climate simulation also facilitates new and substantial findings regarding the role of thermodynamics and transient eddies in P -- E changes reflected in observed changes in major river basins fed by runoff from the TP. The analysis reveals the contrasting convergence/divergence changes between the northwestern and southeastern TP and feedback through latent heat release as an important mechanism leading to the mean P -- E changes in the TP. Show less