Evaluation and Projection Of Changes in Temperature and Precipitation Over Northwest China Based on Cmip6 Models

Abstract

In this paper, thirty four climate models of CMIP6 are used to evaluate and forecast future trend in northwest China under SSP126, SSP245 and SSP585 scenarios in short, medium and long-term. CMIP6 models in temperature and precipitation are identified by applying interannual variability skill score (IVS) between CN05.1 datasets and historical CMIP6 models, which are suitable for Northwest China. Then we assess the characteristics, warming and wetting deviations, and uncertainties in prediction of climatic change according to CMIP6 models over Northwest China. Results show that CMIP6 models applicable to northwest China are AWI-CM-1-1-MR, BCC-CSM2-MR, FGOALS-g3, INM-CM4-8, INM-CM5-0 and MRI-ESM2-0.  Multi model ensemble mean (MMEM) have better capability than individual CMIP6 model in precipitation and temperature. Spatiotemporal climate change over Northwest China shows overall trends of warming and wetting. IVS is ability to estimate CMIP6 model simulation performance in both time and space. the temperature simulation is quite good in Tarim basin and Hexi Corridor Region, and the precipitation is in Plateau region, Altai Mountain, Tianshan Mountain and Hexi Corridor Region. There are cold and wet deviations in Northwest China by common reasons of topography and few stations. Main sources of uncertainties in temperature prediction during this century are model uncertainty (before 2090s) and scenario variability (after 2090s) and model uncertainty in precipitation for CMIP6 becomes the main way of uncertainty.

Keywords: Climate change, Northwest China, CMIP6 models, interannual variability skill score, model uncertainty