Twenty-Seven Years of Scatterometer Surface Wind Analysis over Eastern Boundary Upwelling Systems

Type Article
Date 2021-03
Language English
Author(s) Bentamy Abderrahim1, Grodsky Semyon A2, Cambon Gildas3, Tandeo Pierre4, Capet Xavier5, Roy Claude3, Herbette Steven3, Grouazel AntoineORCID1, 3
Affiliation(s) 1 : Laboratoire d’Océanograpie Physique et Spatial (LOPS), Institut Français pour la Recherche et l’Exploitation de la MER (IFREMER), 29280 Plouzané, France
2 : Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD 20742, USA
3 : Laboratoire d’Océanographie Physique et Spatiale (LOPS), Institut de Recherche et Développment (IRD), 29280 Plouzané, France
4 : Laboratoire Signale et Communication, Institut Mines Télécom Atlantique (IMTA), 29280 Plouzané, France
5 : Laboratoire d’Océanographie et du Climat (LOCEAN), Sorbonne Université, 75005 Paris, France
Source Remote Sensing (2072-4292) (MDPI), 2021-03 , Vol. 13 , N. 5 , P. 940 (28p.)
DOI 10.3390/rs13050940
Note This article belongs to the Special Issue Remote Sensing of Air-Sea Fluxes
Keyword(s) satellite scatterometer, surface wind, upwelling systems, long time series
Abstract

More than twelve satellite scatterometers have operated since 1992 through the present, providing the main source of surface wind vector observations over global oceans. In this study, these scatterometer winds are used in combination with radiometers and synthetic aperture radars (SAR) for the better determination and characterization of high spatial and temporal resolution of regional surface wind parameters, including wind speed and direction, wind stress components, wind stress curl, and divergence. In this paper, a 27-year-long (1992–2018) 6-h satellite wind analysis with a spatial resolution of 0.125° in latitude and longitude is calculated using spatial structure functions derived from high-resolution SAR data. The main objective is to improve regional winds over three major upwelling regions (the Canary, Benguela, and California regions) through the use of accurate and homogenized wind observations and region-specific spatial and temporal wind variation structure functions derived from buoy and SAR data. The long time series of satellite wind analysis over the California upwelling, where a significant number of moorings is available, are used for assessing the accuracy of the analysis. The latter is close to scatterometer wind retrieval accuracy. This assessment shows that the root mean square difference between collocated 6-h satellite wind analysis and buoys is lower than 1.50 and 1.80 m s−1 for offshore and nearshore locations, respectively. The temporal correlation between buoy and satellite analysis winds exceeds 0.90. The analysis accuracy is lower for 1992–1999 when satellite winds were mostly retrieved from ERS-1 and/or ERS-2 scatterometers. To further assess the improvement brought by this new wind analysis, its data and data from three independent products (ERA5, CMEMS, and CCMP) are compared with purely scatterometer winds over the Canary and Benguela regions. Even though the four products are generally similar, the new satellite analysis shows significant improvements, particularly in the upwelling areas.

Full Text
File Pages Size Access
Publisher's official version 28 21 MB Open access
Top of the page

How to cite 

Bentamy Abderrahim, Grodsky Semyon A, Cambon Gildas, Tandeo Pierre, Capet Xavier, Roy Claude, Herbette Steven, Grouazel Antoine (2021). Twenty-Seven Years of Scatterometer Surface Wind Analysis over Eastern Boundary Upwelling Systems. Remote Sensing, 13(5), 940 (28p.). Publisher's official version : https://doi.org/10.3390/rs13050940 , Open Access version : https://archimer.ifremer.fr/doc/00682/79416/