中文摘要：

利用第5次耦合模式比较计划（CMIP5）中35个全球气候模式历史模拟与RCP4.5预估结果,通过贝叶斯模型平均（Bayesian Model Averaging,BMA）对中国气温进行多模式集合研究,给出了中国未来气温变化预估及其不确定性的时空分布。结果表明,中国21世纪冬夏将持续升温,且升温具有冬季高于夏季,北方高于南方的特点。初期（2016—2035年）北方有很大可能（〉80%）升温超过0.7℃,南方升温相同幅度的概率则超过50%;中期（2046—2065年）北方和南方升温超过1.5℃的概率分别为80%和50%;末期（2081—2100年）,北方（南方）有80%（50%）的可能的升温超过2℃。气温预估的不确定性研究发现,无论冬夏,21世纪不同时期升温相对较弱的塔里木盆地、青藏高原南侧和中国东南地区为不确定性低值区,基本低于0.6℃,对应可信度较高,如21世纪初期信噪比超过4;而不确定性的高值区则主要分布在新疆北部、东北平原北部和青藏高原东南侧等升温相对较大的地区,普遍高于1℃,对应可信度较低,如初期信噪比低于2.5。此外,基于信噪比对比发现除青藏高原东部外,其他区域夏季预估的可信度均高于冬季,21世纪末期高于初期,且空间分布特征一致。

英文摘要：

Based on historical simulation experiments and future projections under the RCP4.5 scenario of 35 climate models in the Coupled Model Intercomparison Project Phase five （CMIP5）, the Bayesian Model Averaging （BMA） is applied to project the surface air temperature change and uncertainty over China in the 21 century. Results show a consistent increase in surface air temperature in China, and the air temperature change is larger in the winter than in the summer and larger in the north than in the south. It is very likely （〉80%） that the surface air temperature will increase by 0.7℃ in northern China, and the probability of the same increase in southern China exceeds 50% at the early 21 century （2016 - 2035）. The probabilities of the air temperature increase of 1.5 ℃ in northern and southern China in the middle 21 century （2046 - 2065） are larger than 80% and 50% respectively, and the same probabilities of air temperature increase of 2 ℃ at the end of 21 century （2081 - 2100） are found in northern and southern China. Meanwhile, characteristics of the estimated uncertainty are similar to that of the air temperature change, with the lowest uncertainty of less than 0.6 ℃being found in the Tarim Basin, the southern Tibetan Plateau and southeast China. Large uncertainties of greater than 1℃ are found in northern Xinjiang, northern Northeast China Plain and southeastern Tibetan Plateau, where the reliability of the estimated results is the poorest. Besides, compared with that in the summer, the reliability of projected air temperature change in the winter is lower in most regions except the eastern Tibetan Plateau; and the reliability of the projection at the end of 21 century is higher than that at early 21 century, but with the same spatial distribution of air temperature change.