利用国际耦合模式比较计划第六阶段（CMIP6）多模式的模拟结果，对比观测和青藏高原冻土图评估各模式对当前（1985-2014年）青藏高原与冻土相关气候变量以及多年冻土的模拟能力，并应用多模式集合平均的方法预估了未来4个SSP情景下2021-2040年、2041-2060年、2081-2100年高原多年冻土的变化趋势。结果表明：CMIP6各模式都能够较好地模拟出与冻土相关气候变量的分布特征与趋势，但对于气温的模拟有着较为明显的冷偏差，对于积雪的模拟明显偏大；利用冻结数模型（SFI）计算的当前多年冻土分布与青藏高原冻土图有较好的吻合，1985-2014年的表面多年冻土面积约为134.52×10～4km2（包含湖泊和冰川面积）；随着气温的升高，21世纪青藏高原多年冻土呈现区域退化的趋势，在SSP1-2.6、SSP2-4.5、SSP3-7.0和SSP5-8.5情景下，青藏高原东部、南部以及北部边缘地区多年冻土呈现区域性退化，至2041-2060年间多年冻土面积分别减少13.81×10～4 km2、19.51×10～4 km2、1...

Permafrost has significant impacts on climate change through its strong interaction with the climate system. In order to better understand the permafrost variation and the role it plays in climate change, model outputs from Phase 5 of the Coupled Model Intercomparison Project (CMIP5) are used in the present study to diagnose the near-surface permafrost on the Tibetan Plateau (TP), assess the abilities of the models to simulate present-day (1986-2005) permafrost and project future permafrost change on the TP under four different representative concentration pathways (RCPs). The results indicate that estimations of present-day permafrost using the surface frost index (SFI) and the Kudryavtsev method (KUD) show a spatial distribution similar to that of the frozen soil map on the TP. However, the permafrost area calculated via the KUD is larger than that calculated via the SFI. The SFI produces a present-day permafrost area of 127.2 x 10(4) km(2). The results also indicate that the permafrost on the TP will undergo regional degradation, mainly at the eastern, southern and northeastern edges, during the 21st century. Furthermore, most of the sustainable permafrost will probably exist only in the northwestern TP by 2099. The SFI also indicates that the permafrost area will shrink by 13.3 x 10(4) km(2) (9.7%) and 14.6 x 10(4) km(2) (10.5%) under the RCP4.5 and RCP8.5 scenarios, respectively, in the next 20 years and by 36.7 x 10(4) km(2) (26.6%) and 45.7 x 10(4) km(2) (32.7%), respectively, in the next 50 years. The results are helpful for us to better understand the permafrost response to climate change over the TP, further investigate the physical mechanism of the freeze-thaw process and improve the model parameterization scheme.

利用第五次耦合模式比较计划（CMIP5）多个模式的模拟结果,对比再分析资料和青藏高原（下称高原）冻土图,评估了模式对当前（1986-2005年）高原冻土的模拟能力。在此基础上应用多模式集合平均结果,预估了未来不同典型浓度路径（RCPs）情景下高原地表层多年冻土的可能变化。结果表明:CMIP5耦合模式对高原冻土有一定的模拟能力,采用SFI地面冻结指数模型计算的当前地表层多年冻土分布与高原冻土图有较好的吻合,1986-2005年高原地表层平均多年冻土面积为127.5×10～4km2;多模式集合预估结果显示,高原地表层多年冻土呈现区域性退化趋势,高原东部、南部及北部边缘地区冻土带退化较为明显,有从外围向西北部多年冻土区逐步退化的趋势,RCP2.6、RCP4.5、RCP6.0和RCP8.5情景下未来50年地表层多年冻土面积分别减少约23.9×10～4km2（20.8%）、33.5×10～4km2（27.7%）、25.6×10～4km2（21.1%）和43.5×10～4km2（35.3%...