气候变化领域集成服务门户(CCPortal): Impact of terrain complexity on the turbulence drag coefficient: A case study from the Indian Himalayan region

CCPortal

DOI	10.1016/j.dynatmoce.2021.101201
	Impact of terrain complexity on the turbulence drag coefficient: A case study from the Indian Himalayan region
	Lohani P.; Mukherjee S.
发表日期	2021
ISSN	03770265
卷号	93
英文摘要	The aerodynamic drag coefficient (CD) is conjectured to change (or remains almost uniform) with the horizontal wind speed (U) over a flexible (or fixed) surface element, which is represented with the surface roughness (z0). This conjecture is tested for the near neutral atmospheric turbulence (i.e. when surface stability z/L is almost equal to 0, where z is the measurement height and L is Obukhov length) of monsoon and winter season at an on-slope and a ridge-top site in the Indian Himalaya, wherein the ridge-top site is associated with a higher degree of sensitivity to the roughness element and terrain attributes. This hypothesis is successfully verified for two conditions, (i) the monsoon period observations of ridge-top site are found to have higher z0 due to vegetative growth than the winter period for flows having similar terrain signature, and (ii) the monsoon and winter period observations of on-slope site are noted to have similar z0 for flows having signature of steep terrain. Subsequently, constants (i.e. a and b) of the power-law relationships between CD and U (i.e. CD = aUb), as a function of z0, are optimized. It is noted that the relationship between CD and U has higher sensitivity towards the terrain slope than the vegetative growth. © 2021 Elsevier B.V.
英文关键词	Drag coefficient; Himalayan terrain; Surface roughness
语种	英语
scopus关键词	Aerodynamic drag; Atmospheric turbulence; Drag coefficient; Landforms; Slope stability; Surface roughness; Wind; Degree of sensitivity; Power law relationship; Roughness elements; Surface elements; Surface stability; Terrain attributes; Terrain complexity; Vegetative growth; Atmospheric thermodynamics; atmospheric dynamics; boundary layer; complexity; drag coefficient; orographic effect; power law; surface roughness; terrain; topographic effect; turbulence; wind velocity; Himalayas; India
来源期刊	Dynamics of Atmospheres and Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/178260
作者单位	G.B. Pant National Institute of Himalayan Environment, Kosi-Katarmal, Almora, 263643, India
推荐引用方式 GB/T 7714	Lohani P.,Mukherjee S.. Impact of terrain complexity on the turbulence drag coefficient: A case study from the Indian Himalayan region[J],2021,93.
APA	Lohani P.,&Mukherjee S..(2021).Impact of terrain complexity on the turbulence drag coefficient: A case study from the Indian Himalayan region.Dynamics of Atmospheres and Oceans,93.
MLA	Lohani P.,et al."Impact of terrain complexity on the turbulence drag coefficient: A case study from the Indian Himalayan region".Dynamics of Atmospheres and Oceans 93(2021).