Process-based attribution of long-term surface warming over the Tibetan Plateau

The Tibetan Plateau (TP) has experienced a rapid warming since the 1980s even during the global warming hiatus. Using the European Centre for Medium-Range Weather Forecasts Interim (ERA-Interim) reanalysis and a climate feedback-response analysis method, we attribute the long-term change in near-surface air temperature (SAT) over the TP to external forcing and internal climate processes. Results indicate that over the eastern and central TP, a reduction of surface sensible heat flux going from the surface to the atmosphere and the moistening of atmosphere are responsible for the increase in the annual mean SAT. In the western TP, however, the most important contributors to surface warming are surface latent heat flux, surface albedo, and clouds. In summer (June-July-August), strong water vapour convergence with anomalous ascending motion results in more cloud cover over the central and eastern TP, causing a stronger cooling effect at the surface which is compensated by changes in water vapour and surface sensible heat flux. In winter (December-January-February), the change in surface albedo shows a significant increasing trend in the past 40 years, showing less net downward solar radiation to warm the surface. However, the decadal reduction of surface sensible heat flux and increase of heat storage result in a warming surface.