|
|
|
|
|
| Mouche, Alexis; Chapron, Bertrand; Knaff, John; Zhao, Yili; Zhang, Biao; Combot, Clement. |
| C‐Band high resolution radar (SAR) is the only space‐borne instrument able to probe at very high resolution and over all ocean basins the sea surface under extreme weather conditions. When co‐analyzed with Stepped Frequency Microwave Radiometer (SFMR) wind estimates, the radar backscatter signals acquired in major Hurricanes from Sentinel‐1 and Radarsat‐2 SAR, reveal high sensitivity in the cross‐polarized channel for wind speeds up to 75 m/s. The combination of the two co‐ and cross‐ polarized channels can then be used to derive high resolution surface wind estimates. The retrieval methods and impacts of intense rainfall are discussed in the context of a Hurricane Irma (2017) case study. On September 7, 2017, Sentinel‐1 measurements intercepted Hurricane... |
| Tipo: Text |
Palavras-chave: SAR; Copolarization and cross-polarization; High resolution; Category 5 Hurricane; Hurricane Irma. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00497/60898/64236.pdf |
| |
|
|
| Combot, Clement; Mouche, Alexis; Knaff, John; Zhao, Yuan; Zhao, Yuan; Vinour, Leo; Quilfen, Yves; Chapron, Bertrand. |
| To produce more precise descriptions of air-sea exchanges under Tropical Cyclones (TCs), spaceborne Synthetic Aperture Radar (SAR) instruments provide unique capabilities to probe the ocean surface conditions, at very high spatial resolution, and on synoptic scales. Using highly-resolved (3 km) wind fields, an extensive database is constructed from Radarsat-2 and Sentinel-1 SAR acquisitions. Spanning 161 tropical cyclones, the database covers all TC intensity categories that have occurred in five different TC basins, and include 29 cases coincident with SFMR measurements. After locating the TC center, a specific methodology is applied to filter out areas contaminated by heavy precipitations to help extract, for each acquisition, the maximum wind speed... |
| Tipo: Text |
|
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00654/76589/77738.pdf |
| |
|
|
|
