亚洲高山区全新世中期气候及其影响下的冰川模拟

本文利用一个1 km分辨率冰盖模式和11个PMIP4全球气候模式,研究了全新世中期亚洲高山区气候和冰川的变化特征。多模式集合平均结果显示,(1)全新世中期亚洲高山区年平均温度较工业革命前期降低了约0.7 ℃,夏季气温升高约0.7 ℃,冬季气温降低约1.8 ℃,全新世中期年平均降水略微增加(0.5%),但夏季和冬季降水分别增加和减少了约16%;(2)全新世中期亚洲高山区冰川较工业革命前期整体显著退缩,面积减少了约13%,体积减小了约8%。在区域尺度上,全新世中期亚洲高山区北部冰川的面积(体积)减少了约58%(47%),西部冰川的面积(体积)减少了约26%(25%),而南部冰川的面积(体积)增加了约20%(39%);(3)全新世中期夏季升温主导亚洲高山区北部和西部冰川的退缩,而降水增多是亚洲高山区南部冰川扩张的首要控制因子。本研究有助于加深理解全新世中期亚洲高山区冰川的变化格局和驱动因子。

Climate change and the associated glacier response in High-Mountain Asia during the mid-Holocene: A modeling study

Using a 1-km resolution ice sheet model and the results from 11 global climate models in PMIP4, we investigate the spatial features of climatic changes in High-Mountain Asia (HMA) and their effects on glaciation during the mid-Holocene. The multi-model ensemble mean demonstrates that the annual mean temperature averaged across HMA reduces by ~0.7 ℃ during the mid-Holocene relative to pre-industrial, with a warming (0.7 ℃) and cooling (0.7 ℃) in summer and winter, respectively. The annual mean precipitation during the mid-Holocene shows a slight increase (0.5%) in HMA, whereas summer (winter) precipitation changes by +16% (-16%). HMA glaciers exhibit an obvious recession during the mid-Holocene relative to pre-industrial, with a reduction in ice extent (volume) by 13% (8%). Regarding the regional pattern, glaciers of the northern and western HMA retreat by ~58% (47%) and ~26% (25%), respectively, in terms of ice extent (volume). In contrast, glacier advance is observed over the southern HMA, with an increase in ice extent (volume) by ~20% (39%). Additionally, sensitivity experiments suggest that summer warming during the mid-Holocene dominate glacier recession in the northern and western HMA, whereas enhanced precipitation contributes largely to glacier advance in the southern HMA. These results may help to deepen our understanding of the variation of HMA glaciation during the mid-Holocene.