Climate Change Projection on the Tibetan Plateau:Results of CMIP5 Models

Climate change for the 21st century over the Tibetan Plateau (TP) is projected using multiple climate models within the phase five of the Coupled Model Intercomparison Project under the Representative Concentration Pathway 4.5 (RCP4.5) scenario.These models have a demonstrated ability to simulate modern climatology.The results show an annual warming trend of 0.26℃ per decade, which correlates positively with the topographical height in 2006-2100.With respect to the reference period 1986-2005, the TP annual temperature increases 2.7℃ in the 2090s, which is stronger than the warming in the early and middle 21st century.In the early, middle, and end periods, annual warming is 0.8-1.3℃, 1.6-2.5℃, and 2.1-3.1℃, respectively.Temperature increases are seen in all seasons, with the strongest warming occurring in winter.On the contrary, overall annual precipitation increases slightly on the TP, with a trend of 1.15% per decade during 2006-2100 and an increase of 10.4% in the 2090s relative to the reference period.Annual precipitation ranges from -1.8% to 15.2% in the early period, from -0.9% to 17.8% in the middle period, and from 1.4% to 21.3% in the end period.Precipitation generally increases in all seasons; the summer increase is larger compared with other seasons, particularly for the end of the 21st century.The annual precipitation increase occurs mainly in summer.It is noted that the above results differ somewhat among models, which indicates a relatively large level of uncertainty and a relatively high (low) reliability of temperature (precipitation) projection.