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DOI	10.1016/j.atmosres.2021.105658
	Summer afternoon precipitation associated with wind convergence near the Himalayan glacier fronts
	Lin C.; Yang K.; Chen D.; Guyennon N.; Balestrini R.; Yang X.; Acharya S.; Ou T.; Yao T.; Tartari G.; Salerno F.
发表日期	2021
ISSN	0169-8095
卷号	259
英文摘要	Little is known about the effects of glacier-air interactions on the Himalayan glacier mass balance. Until this knowledge gap is filled, a reliable projection of the future changes in the Himalayan glaciers is hardly possible. Here, we describe the drying effect of the katabatic winds on the up-valley summer monsoon flows by creating favorable conditions for local convergence-induced precipitation to occur near the glacier fronts. We postulate that this retarding effect on the up-valley monsoon flows results in a negative feedback mechanism mediated by glacier-air interactions, in which glacial retreat pushes precipitation upwards as the down-valley katabatic winds weaken, resulting in greater local precipitation and enhanced snow accumulation across the upper parts of the Himalayan glaciers. Our analyses are based on the exclusive data recorded in the Khumbu valley and the Langtang valley in the Nepalese Himalayas. These data revealed higher afternoon precipitation in summer associated with surface wind convergence near the glacier fronts and a sharp decrease in the temperature lapse rate over the glacier surfaces. The principle of the observed phenomena was proven by our high-resolution modeling sensitive experiment, which involved two simulations, one with the present glaciers and the other without. This numerical experiment also supports the proposed negative feedback. Furthermore, we report a low deuterium excess near the glacier fronts, indicating below-cloud re-evaporation facilitated by the local convergence induced by the dry katabatic winds. Our study suggests that current models may overestimate the retreat of Himalayan glaciers because they have completely ignored the glacier-air interactions. © 2021 The Author(s)
英文关键词	Elevational dependence; Feedback mechanism; Glacier mass balance; Glacier-air interactions; Himalayan glaciers
来源期刊	Atmospheric Research
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/236694
作者单位	Regional Climate Group, Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden; Rossby Centre, Swedish Meteorological and Hydrological Institute, Norrköping, Sweden; Ministry of Education Key Laboratory for Earth System Modelling and Department of Earth System Science, Tsinghua University, Beijing, China; CAS Center for Excellence in Tibetan Plateau Earth System Sciences, Chinese Academy of Sciences, Beijing, China; Water Research Institute, National Research Council (IRSA-CNR), Rome, Italy; Water Research Institute, National Research Council (IRSA-CNR), Brugherio, Italy; Key Laboratory of Tibetan Environmental Changes and Land Surface Process, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; Central Department of Hydrology and Meteorology, Tribhuvan University, Kathmandu, Nepal
推荐引用方式 GB/T 7714	Lin C.,Yang K.,Chen D.,et al. Summer afternoon precipitation associated with wind convergence near the Himalayan glacier fronts[J],2021,259.
APA	Lin C..,Yang K..,Chen D..,Guyennon N..,Balestrini R..,...&Salerno F..(2021).Summer afternoon precipitation associated with wind convergence near the Himalayan glacier fronts.Atmospheric Research,259.
MLA	Lin C.,et al."Summer afternoon precipitation associated with wind convergence near the Himalayan glacier fronts".Atmospheric Research 259(2021).