Deviation of Wind Stress From Wind Direction Under Low Wind Conditions

doi:10.1029/2018JC014137

	Deviation of Wind Stress From Wind Direction Under Low Wind Conditions
	Chen, Sheng 1,2,3; Qiao, Fangli 2,3,4; Huang, Chuan Jiang 2,3; Zhao, Biao 2,3,4
刊名	JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
	2018-12
卷号	123 期号:12 页码:9357-9368
关键词	Wind Stress Low Wind Speeds Swells Nonstationarity Stress Offwind Angle
ISSN号	2169-9275
DOI	10.1029/2018JC014137
英文摘要	The deviation of the wind stress vector from the wind direction at the air-sea interface under low wind conditions was investigated based on direct eddy covariance flux measurements taken at a coastal tower in the northern South China Sea. The wind stress deviates significantly from the mean wind direction under low wind conditions, with the deviation angle sometimes exceeding 90 degrees, indicating upward momentum transfer from the ocean to the atmosphere. Negative downwind drag coefficient values begin to occur at a wind speed of approximately 4m/s. Our results show that ocean swells and nonstationary airflow play critical roles in wind stress. Prominent peaks at the dominant swell frequency in the vertical velocity spectra are observed at a height of 17m over the mean sea surface, implying that swell-induced perturbations can reach a height of at least 17m, and the wave boundary layer can extend more than 10m above the sea surface. The results of our analysis indicate that at the observation height, the influence of nonstationarity in the wind field is more significant than that of swell-induced motions on the deviation of wind stress. After the removal of nonstationary motions, the deviation angles of the wind stress from the wind direction are generally reduced and vary substantially at low wind speeds.
资助项目	Qingdao National Laboratory for Marine Science and Technology through the Transparency Program of Pacific Ocean-South China Sea-Indian Ocean[2015ASKJ01]
WOS关键词	AIR-SEA FLUXES ; LAYER TURBULENCE ; BOUNDARY-LAYERS ; SURFACE-LAYER ; OCEAN ; SWELL ; VECTOR ; WAVES ; ANGLE
WOS研究方向	Oceanography
语种	英语
出版者	AMER GEOPHYSICAL UNION
WOS记录号	WOS:000456405900039
内容类型	期刊论文
源URL	[http://ir.fio.com.cn:8080/handle/2SI8HI0U/26160]
专题	自然资源部第一海洋研究所
通讯作者	Qiao, Fangli
作者单位	1.Ocean Univ China, Coll Ocean & Atmospher Sci, Qingdao, Peoples R China 2.Minist Nat Resources, Inst Oceanog 1, Qingdao, Peoples R China 3.Qingdao Natl Lab Marine Sci & Technol, Lab Reg Oceanog & Numer Modeling, Qingdao, Peoples R China 4.Minist Nat Resources, Key Lab Marine Sci & Numer Modeling, Qingdao, Peoples R China
推荐引用方式 GB/T 7714	Chen, Sheng,Qiao, Fangli,Huang, Chuan Jiang,et al. Deviation of Wind Stress From Wind Direction Under Low Wind Conditions[J]. JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS,2018,123(12):9357-9368.
APA	Chen, Sheng,Qiao, Fangli,Huang, Chuan Jiang,&Zhao, Biao.(2018).Deviation of Wind Stress From Wind Direction Under Low Wind Conditions.JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS,123(12),9357-9368.
MLA	Chen, Sheng,et al."Deviation of Wind Stress From Wind Direction Under Low Wind Conditions".JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS 123.12(2018):9357-9368.