气候变化领域集成服务门户(CCPortal): Biases in Structure Functions from Observations of Submesoscale Flows

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DOI	10.1029/2019JC015769
	Biases in Structure Functions from Observations of Submesoscale Flows
	Pearson J.; Fox-Kemper B.; Pearson B.; Chang H.; Haus B.K.; Horstmann J.; Huntley H.S.; Kirwan A.D.; Jr.; Lund B.; Poje A.
发表日期	2020
ISSN	21699275
卷号	125 期号:6
英文摘要	Surface drifter observations from the LAgrangian Submesoscale ExpeRiment (LASER) campaign in the Gulf of Mexico are paired with Eulerian (ship-borne X-band radar) data to demonstrate that velocity structure functions from drifters differ systematically from Eulerian structure functions over scales from 0.4 to 7 km. These differences result from drifters oversampling surface convergences and regions of intense vorticity. The first-, second-, and third-order structure functions are calculated using quasi-Lagrangian (drifter) and Eulerian data from approximately the same location and time. Differences between quasi-Lagrangian and Eulerian structure functions are attributed to two forms of bias. The first bias results from the mean divergence or vorticity of the background flow creating nonzero first-order structure functions. This background bias affects both quasi-Lagrangian and Eulerian data when insufficiently time-averaged. It severely biases the drifter third-order structure functions but is smaller in Eulerian structure functions at both second and third order. This bias can be corrected for using lower-order structure functions. The second form of bias results from drifters accumulating in regions with flow statistics that differ from undersampled regions. This accumulation bias is diagnosed by identifying the dependence of the Eulerian structure functions on divergence and vorticity as well as scale. Together, both biases suggest that caution is needed when interpreting second-order drifter statistics and that linking raw third-order drifter statistics to energy fluxes is often erroneous in ocean data: Even with background correction and sufficient time-averaging, drifters overestimate the Eulerian estimate of the third-order structure function by up to a factor of 5 when signs are consistent. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Gulf of Mexico; Structure Functions; Surface Drifters; X-band Radar
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/186849
作者单位	Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, United States; College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, United States; School of Marine Science and Policy, University of Delaware, Newark, DE, United States; Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, United States; Helmholtz Zentrum Geesthacht, Geesthacht, Germany; Department of Mathematics, College of Staten Island, City University of New York, Staten Island, NY, United States
推荐引用方式 GB/T 7714	Pearson J.,Fox-Kemper B.,Pearson B.,et al. Biases in Structure Functions from Observations of Submesoscale Flows[J],2020,125(6).
APA	Pearson J..,Fox-Kemper B..,Pearson B..,Chang H..,Haus B.K..,...&Poje A..(2020).Biases in Structure Functions from Observations of Submesoscale Flows.Journal of Geophysical Research: Oceans,125(6).
MLA	Pearson J.,et al."Biases in Structure Functions from Observations of Submesoscale Flows".Journal of Geophysical Research: Oceans 125.6(2020).