Abstract:

The monthly temperature and precipitation data from 162 meteorological observation stations were used to evaluate the simulation performance of the CCSM4 model and predict the climate change scenario in Northeast China from 2021 to 2050.Results show that monthly mean temperature and precipitation values simulated by the long-term historical climate CCSM4 mode simulation experiment from 1961 to 2005 can reproduce the Northeast regional annual average temperature,rainfall spatial distribution form.However,the temperature simulation values are lower than those of observations.The temperature error in 91.4% stations is within 1.5 ℃.The precipitation center is slightly shifted to the north compared with the observations.There is a positive bias of 35.18 mm of average precipitation for the whole region.For 2021-2050,the annual average temperature in Northeast China increases.The amplitude of increased temperature in the high latitude is larger than that in the low latitudes.Compared with the benchmark year,the temperature increasing amplitudes under RCP2.6,RCP4.5 and RCP8.5 scenarios are 6.00 ℃,5.86 ℃ and 6.42 ℃,respectively.The annual precipitation distribution presents a pattern of decreasing from southeast to northwest.The high-value center in precipitation appears at the southeast part of the junction zone of Jilin and Liaoning provinces.Under RCP2.6,RCP4.5 and RCP8.5 scenarios,the increasing percentage in precipitation is 15.2%,3.1%,and 2.0%,respectively for the whole research area.

Key words: CCSM4, Temperature, Precipitation, Evaluation, Projection