Simulations And Projections Of Climate Change In Northeast China Using CMIP5 Models

Based on observational data of CN05 (daily observations on a 0.5° latitude-longitude grid over China), the performance of 26 models in CMIP5 (Coupled Model Inter-comparison Project Phase 5) in simulating climate change in Northeast China were compared and evaluated. Six best-fit models were selected by using Taylor Diagram, and used in a multi-model ensemble (MME) mean for projecting future changes in climate under different representative concentration pathways (RCPs). Results show that:(i) Most of the models are capable of revealing the significant warming trend during 1961-2005 in Northeast China, and well reproduce the spatial distribution of surface air temperatures (spatial correlation coefficients> 0.8). But they are limited in realistically simulating the inter-annual variations of mean surface air temperatures. The MME of the six best-fit models out-perform most of the individual models. (ii) The performance in simulating precipitation varies greatly among various models. The MME approach well reproduces the spatial pattern of precipitation (spatial correlation coefficient= 0.8), albeit poor performance in simulating the inter-annual variations and linear trend of regional mean precipitation, (iii) An ongoing warming is predicted under different RCPs in Northeast China from 2006 to 2099, especially under RCP 8.5 (0.57℃/10a), which is twice that under RCP 4.5 (0.24℃/10a). Spatially, the northern part of Northeast China generally shows greater and more rapid warming than the southern part, (iv) The annual mean precipitation is predicted to increase in future but with great fluctuations. By the end of the 21st century, the annual mean precipitation is predicted to increase by 10.37% under RCP4.5 and 17.69% under RCP8.5, respectively. Future change in precipitation over most parts of Northeast China is predicted to intensify, with the western part of Liaoning province changing the most. (v) According to water deficit, with time, a wetting trend is predicted under RCP 4.5 in Northeast China; most parts are projected to become wetter in the mid- and late 21th century. In contrast, under RCP 8.5 most years in future would be under water deficit; by the mid- to late 21st century, more than two-thirds of the region would become drier.