Abstract:

Taking the climate of the Last Glacial Maximum (about 26000 years ago to 19000 years ago) as the background climate, the authors study the climatic impact of the expansion of the glacier on the Tibetan Plateau using the atmospheric general circulation model CAM4 coupled to the land surface model CLM4. The results show that in summer the increased glacier extent over Qinghai-Tibet Plateau has a significant impact on the climate in the Northern Hemisphere. Besides the significant temperature decrease on the glacier, atmospheric teleconnection can also cause significant warming near the Bering Strait. In addition, the disturbance caused by glaciers will enhance the South Asian summer monsoon and increase the precipitation there. Finally, through comparing the influence of the scale of the Qinghai-Tibetan glaciers on the climate under the different climate states of the Last Glacial Maximum (LGM) and Pre-industrial (PI) periods, it was found that their influence in the PI period was significantly less than that in the LGM period. It indicates that impact of Tibetan glaciers on climate is related with the climate state.

Key words: paleoclimate simulation, Qinghai-Tibet Plateau glacier, last glacial maximum, monsoon, teleconnection

摘要：

以末次冰盛期(约2.6~1.9万年前)的气候为背景, 利用大气模式CAM4耦合陆面模式CLM4, 对青藏高原冰川规模扩大对气候产生的影响进行研究。结果表明, 末次冰盛期青藏高原冰川对北半球夏季的气候影响较显著, 除在冰川分布区引起显著的降温外, 通过遥相关作用, 还使得白令海峡附近显著升温。另外, 冰川产生的扰动会显著地增强南亚夏季风, 增加南亚地区降水。对比末次冰盛期与工业革命前时期不同气候态下青藏高原冰川规模扩大对气候的影响, 发现工业革命前时期的影响显著小于末次冰盛期, 说明青藏高原冰川对气候的影响与背景气候态有关。

关键词: 古气候模拟, 青藏高原冰川, 末次冰盛期, 季风, 遥相关