Simultaneous observations of ocean surface winds and waves by Geosat radar altimeter and airborne synthetic aperture radar during the 1988 Norwegian Continental Shelf Experiment

1991 ◽  
Vol 96 (C6) ◽  
pp. 10467 ◽  
Author(s):  
Nelly M. Mognard ◽  
Johnny A. Johannessen ◽  
Charles E. Livingstone ◽  
David Lyzenga ◽  
Robert Shuchman ◽  
...  
Keyword(s):  
Synthetic Aperture Radar ◽  
Continental Shelf ◽  
Ocean Surface ◽  
Synthetic Aperture ◽  
Surface Winds ◽  
Radar Altimeter ◽  
Ocean Surface Winds ◽  
Norwegian Continental Shelf ◽  
Aperture Radar

scholarly journals Characteristics of Ocean Surface Winds in the Lee of an Isolated Island Observed by Synthetic Aperture Radar

2010 ◽  
Vol 139 (6) ◽  
pp. 1744-1761 ◽  
Author(s):  
Osamu Isoguchi ◽  
Masanobu Shimada ◽  
Hiroshi Kawamura
Keyword(s):  
Synthetic Aperture Radar ◽  
Atmospheric Stability ◽  
Ocean Surface ◽  
Synthetic Aperture ◽  
Leeward Side ◽  
Surface Winds ◽  
Low Level ◽  
Ocean Surface Winds ◽  
Low Level Jet ◽  
Aperture Radar

Abstract Characteristics of ocean surface winds around an isolated island are examined in relation to atmospheric stability using a synthetic aperture radar (SAR) and rawinsonde sounding observations. The SAR-derived winds on 22 May 2009 indicate a low-level jet extending over 30 km behind the island. Around the time of SAR acquisition, winds intensified on the leeward side in association with the stabilization of stratified flows, which suggests the connection of the SAR-derived jet with downslope winds. A number of SAR-derived winds elucidate typical wind patterns and their transitions depending on the nondimensional mountain height . For cases of large (>2), a wake is formed in the lee of the island and low-level jets produce strong wind shear on both sides of the wake. For cases of relatively small (<1.75), although a weak wind region is formed behind the mountain, no wind jets develop. As a transition of the above two cases , a low-level jet develops in the lee of the island, as in the case on 22 May 2009. These wake configurations and their -dependent transitions seem to correspond to major regimes for hydrostatic flow over topography with constant upstream speed and buoyancy frequency: small-amplitude waves , wave breaking , and flow splitting . It is noted that the ocean surface winds behind the island are very sensitive to around the transition point, changing up and down. The occurrence of each wind pattern shows clear seasonal features dependent on atmospheric stability.

scholarly journals Assessment of DUACS Sentinel-3A Altimetry Data in the Coastal Band of the European Seas: Comparison with Tide Gauge Measurements

2020 ◽  
Vol 12 (23) ◽  
pp. 3970
Author(s):  
Antonio Sánchez-Román ◽  
Ananda Pascual ◽  
Marie-Isabelle Pujol ◽  
Guillaume Taburet ◽  
Marta Marcos ◽  
...  
Keyword(s):  
Synthetic Aperture Radar ◽  
Tide Gauge ◽  
Synthetic Aperture ◽  
Altimetry Data ◽  
Radar Altimeter ◽  
Long Wave ◽  
Tide Gauge Measurements ◽  
European Seas ◽  
Aperture Radar

The quality of the Data Unification and Altimeter Combination System (DUACS) Sentinel-3A altimeter data in the coastal area of the European seas is investigated through a comparison with in situ tide gauge measurements. The comparison was also conducted using altimetry data from Jason-3 for inter-comparison purposes. We found that Sentinel-3A improved the root mean square differences (RMSD) by 13% with respect to the Jason-3 mission. In addition, the variance in the differences between the two datasets was reduced by 25%. To explain the improved capture of Sea Level Anomaly by Sentinel-3A in the coastal band, the impact of the measurement noise on the synthetic aperture radar altimeter, the distance to the coast, and Long Wave Error correction applied on altimetry data were checked. The results confirmed that the synthetic aperture radar altimeter instrument onboard the Sentinel-3A mission better solves the signal in the coastal band. Moreover, the Long Wave Error processing contributes to reduce the errors in altimetry, enhancing the consistency between the altimeter and in situ datasets.

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