气候变化领域集成服务门户(CCPortal): Impacts of the Westerlies on Planetary Boundary Layer Growth Over a Valley on the North Side of the Central Himalayas

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DOI	10.1029/2020JD033928
	Impacts of the Westerlies on Planetary Boundary Layer Growth Over a Valley on the North Side of the Central Himalayas
	Lai, Yue; Chen, Xuelong; Ma, Yaoming; Chen, Deliang; Zhaxi, Suolang
通讯作者	Chen, XL ; Ma, YM (通讯作者)
发表日期	2021
ISSN	2169-897X
EISSN	2169-8996
卷号	126 期号:3
英文摘要	This study focused on planetary boundary layer (PBL) growth in winter under the influence of the westerlies over the Rongbuk Valley on the north side of the central Himalayas. Two sunny November days in 2014 with different synoptic conditions in terms of large-scale wind direction and speed were selected to investigate the ways in which large-scale synoptic forcing affected the vertical structure of the PBL, atmospheric stability, surface wind field, and land surface energy fluxes. This was done by using radiosonde and in-situ measurements, the European Centre for Medium-Range Weather Forecasts ERA5 reanalysis data set, and a one-dimensional model. The results revealed that the valley winds and PBL growth were strongly influenced by the variations of the westerlies, which prevail in this region during the winter. When the synoptic wind direction at the height of the mountain ridges was parallel to the axis of the valley and strong, the downward transmission of the westerlies to the valley floor (DTWTV) was strong, causing high near-surface wind speeds and sensible heat flux values. These conditions, together with a deep residual layer, unstable atmosphere, and thermally driven local wind, produced an extremely deep PBL (9 km above sea level) in the early afternoon of November 23. When the synoptic wind direction at the ridge height intersected the axis of the valley and was weak, the DTWTV was weak, and the PBL became relatively low on November 28. These results demonstrate that the interaction between the topography and synoptic circulation plays a critical role in PBL growth.
英文关键词	Himalayas; planetary boundary layer; thermally driven wind; Tibetan Plateau; westerlies
语种	英语
WOS研究方向	Meteorology & Atmospheric Sciences
WOS类目	Meteorology & Atmospheric Sciences
WOS记录号	WOS:000620132700003
来源期刊	JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/260270
推荐引用方式 GB/T 7714	Lai, Yue,Chen, Xuelong,Ma, Yaoming,et al. Impacts of the Westerlies on Planetary Boundary Layer Growth Over a Valley on the North Side of the Central Himalayas[J]. 中国科学院青藏高原研究所,2021,126(3).
APA	Lai, Yue,Chen, Xuelong,Ma, Yaoming,Chen, Deliang,&Zhaxi, Suolang.(2021).Impacts of the Westerlies on Planetary Boundary Layer Growth Over a Valley on the North Side of the Central Himalayas.JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES,126(3).
MLA	Lai, Yue,et al."Impacts of the Westerlies on Planetary Boundary Layer Growth Over a Valley on the North Side of the Central Himalayas".JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES 126.3(2021).