气候变化领域集成服务门户(CCPortal): Evaluation of Radial Ocean Surface Currents Derived From Sentinel-1 IW Doppler Shift Using Coastal Radar and Lagrangian Surface Drifter Observations

CCPortal

DOI	10.1029/2019JC015743
	Evaluation of Radial Ocean Surface Currents Derived From Sentinel-1 IW Doppler Shift Using Coastal Radar and Lagrangian Surface Drifter Observations
	Moiseev A.; Johnsen H.; Hansen M.W.; Johannessen J.A.
发表日期	2020
ISSN	21699275
卷号	125 期号:4
英文摘要	Ocean surface radial velocities (RVLs) derived from the Sentinel-1 A/B Interferomic Wide (IW) mode Doppler frequency shift observations are regularly acquired over the Norwegian coastal zone. These data can be used to complement existing ocean observation systems with high-resolution (up to 1.5 × 1.5 km) spatial ocean surface current (OSC) maps. In this study, Sentinel-1 IW Level 2 OSC retrievals were obtained from 2 months (October–November 2017) of raw Doppler shift observations acquired over the Norwegian Coastal Current (NCC). The results were evaluated using coastal high-frequency radar (HFR) and Lagrangian ocean surface drifter observations. The analysis shows that distinct patterns of the NCC, with range directed currents reaching up to 0.7 m/s, can be detected in the SAR data. The mean bias between Synthetic Aperture Radar (SAR) and HFR observations was −0.08 m/s and the root mean square deviation (RMSD) was 0.25 m/s. In comparison, the agreement between the SAR-derived OSC and the trajectories from Lagrangian surface drifters showed a mean bias of 0.02 m/s and an RMSD of 0.24 m/s. The accuracy of the SAR OSC retrievals rely on precise wind-wave bias correction. Hence, the accuracy of the model wind field (speed and direction) is crucial. The sea state contribution must also be taken into account during the bias correction. A typical required accuracy of the OSC velocity is on the order of 0.1 m/s. Therefore, the comparisons demonstrate that the use of SAR for OSC retrieval is promising. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Doppler shift; HF-radar; ocean surface current; Sentinel-1; synthetic aperture radar; validation
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/186902
作者单位	Nansen Environmental and Remote Sensing Center, Bergen, Norway; NORCE Norwegian Research Center AS, Tromso, Norway; Norwegian Meteorological Institute, Bergen, Norway; Geophysical Institute, University of Bergen, Bergen, Norway
推荐引用方式 GB/T 7714	Moiseev A.,Johnsen H.,Hansen M.W.,et al. Evaluation of Radial Ocean Surface Currents Derived From Sentinel-1 IW Doppler Shift Using Coastal Radar and Lagrangian Surface Drifter Observations[J],2020,125(4).
APA	Moiseev A.,Johnsen H.,Hansen M.W.,&Johannessen J.A..(2020).Evaluation of Radial Ocean Surface Currents Derived From Sentinel-1 IW Doppler Shift Using Coastal Radar and Lagrangian Surface Drifter Observations.Journal of Geophysical Research: Oceans,125(4).
MLA	Moiseev A.,et al."Evaluation of Radial Ocean Surface Currents Derived From Sentinel-1 IW Doppler Shift Using Coastal Radar and Lagrangian Surface Drifter Observations".Journal of Geophysical Research: Oceans 125.4(2020).