The Chinese Gaofen-3 (GF-3) synthetic aperture radar (SAR) launched by the China Academy of Space Technology (CAST) has operated at C-band since September 2016. To date, we have collected 16/42 images in vertical-vertical (VV)/horizontal-horizontal (HH) polarization, covering National Data Buoy Center (NDBC) buoy measurements Oceanic and Atmospheric Administration (NOAA) around U.S. western coastal waters. Wind speeds from NDBC situ buoys are up to 15 m/s buoy-measured significant wave...

Over the past several decades, an increasing number of studies have focused on global view swell and wind sea climate. However, our understanding is still incomplete as lack integrated description for all wave components. In this paper, European Centre Medium-Range Weather Forecasts (ECMWF) Era-medium data used to run WAVEWATCH III model fields in 2010 are reproduced. Using spectra energy partition (SEP) method, two-dimensional were separated detailed information components was obtained. We...

Abstract Hai Yang-2 ( HY-2 ) satellite altimeter measurements of significant wave height are analyzed over the period from 1 October 2011 to 6 December 2014. They calibrated and validated against in situ buoys other concurrently operating altimeters: Jason-2 , CryoSat-2 Satellite with Argos ALtiKa SARAL ). In general, agree well buoy measurements, a bias −0.22 m root-mean-square error (RMSE) 0.30 m. When reduced major axis (RMA) regression procedure was applied entire period, RMSE by 33% 0.2...

The purpose of our work is to determine the feasibility and effectiveness retrieving sea surface wind speeds from C-band cross-polarization (herein vertical-horizontal, VH) Chinese Gaofen-3 (GF-3) SAR images in typhoons. In this study, we have collected three GF-3 acquired Global Observation (GLO) Wide ScanSAR (WSC) mode during summer 2017 China Sea, which includes typhoons Noru, Doksuri Talim. These were collocated with simulations at 0.12° grids a numeric model, called Regional...

With the improvement in microwave radar technology, spaceborne synthetic aperture (SAR) is widely used to observe tropical cyclone (TC) wind field. Based on European Space Agency Sentinel-1 Interferometric Wide swath (IW) mode imagery, this paper evaluates correlation between vertical transmitting–horizontal receiving (VH) polarization signals and extreme ocean surface speeds (>40 m/s) under strong TC conditions. A geophysical model function (GMF) IW retrieval after noise removal...

An ocean surface wave retrieval algorithm, Parameterized First-guess Spectrum Method (PFSM), which was initially developed for C-band Synthetic Aperture Radar (SAR), is modified to extract parameters from X-band TerraSAR-X (TS-X) images. Wave parameters, including significant height (SWH) and mean period (MWP) were extracted nine TS-X HH-polarization images compared in situ buoy measurements. The range of these retrievals 1 5 m SWH 2 10 s MWP. accuracy could reach 80%. After that, a total 16...

Our work describes the accuracy of Chinese quad-polarization Gaofen-3 (GF-3) synthetic aperture radar (SAR) wave mode data for retrieval and provides guidance operational applications GF-3 SAR. In this study, we evaluated SAR-derived significant height (SWH) from 10,514 SAR images with visible streaks acquired in by using existing algorithms, e.g., theoretical-based algorithm parameterized first-guess spectrum method (PFSM), empirical CSAR_WAVE2 VV-polarization, (Q-P). The retrieved SWHs...

In contrast to co-polarization (VV or HH) synthetic aperture radar (SAR) images, cross-polarization (CP for VH HV) SAR images can be used retrieve sea surface wind speeds larger than 20 m/s without knowing the directions. this paper, a new speed retrieval model is proposed European Space Agency (ESA) Sentinel-1A (S-1A) Extra-Wide swath (EW) mode VH-polarized images. Nineteen S-1A under tropical cyclone condition observed in 2016 hurricane season and matching data from Soil Moisture Active...

In this study, an empirical algorithm is proposed to retrieve significant wave height (SWH) from dual-polarization Sentinel-1 (S-1) synthetic aperture radar (SAR) imagery collected under cyclonic conditions. The retrieval scheme based on the well-known CWAVE function that here updated deal with multi-polarization S-1 SAR measurements using interferometric wide (IW) and Extra Wide-Swath (EW) imaging modes, First, a training dataset consists of six images conditions exploited both tune check...

Abstract Recent studies indicate that the cross-polarization synthetic aperture radar (SAR) images have ability of retrieving high wind speed on ocean surface without direction input. This study presents a new approach for tropical cyclone (TC) retrieval utilizing thermal-noise-removed Sentinel-1 dual-polarization (VV + VH) Extra-Wide Swath (EW) Mode products. Based 20 9 TCs observed in 2016 and 2018 SAR-collocated European Centre Medium-Range Weather Forecasts (ECMWF) fifth-generation...

In this study, we proposed an empirical algorithm for significant wave height (SWH) retrieval from TerraSAR-X/TanDEM (TS-X/TD-X) X-band synthetic aperture radar (SAR) co-polarization (vertical-vertical (VV) and horizontal-horizontal (HH)) images. As the existing at X-band, i.e., XWAVE, is applied HH-polarization TS-X/TD-X image, polarization ratio (PR) has to be used inverting wind speed, which treated as input in XWAVE. Wind speed encounters saturation tropical cyclone. our work, replaced...

The motivation of this work is to explore the possibility typhoon wave retrieval (the main parameter significant height (SWH)) for C-band Gaofen (GF-3) synthetic aperture radar (SAR) with a wide swath coverage (>400 km). We aim establish an analysis in subresolution-scale (approximately 20 × km2) on GF-3 SAR through SAR-measured parameters, including normalized cross section (NRCS) and variance image (herein called cvar), which are basic variables empirical algorithm independent visible...

Abstract This study presents a new approach for hurricane wind direction retrieval utilizing rainband streaks contained in synthetic aperture radar (SAR) images without eye information, based on the inflow angle. To calculate field, method estimating location of center is given. In this paper, four Sentinel-1A ( S-1A ) with are used to clarify estimation method. Three SAR studied evaluate accuracy The estimated locations centers show good agreement track data provided by National Oceanic and...

Abstract Ocean surface waves play a significant role in regulating the sea temperature and mixed layer depth, which are essential for accurate prediction of tropical cyclone (TC) intensity. The effects wave breaking orbital motion induced mixing on TC intensity size investigated using coupled ocean‐atmosphere‐wave model both idealized real cases. results show that lead to greater cooling deepening, resulting decreases owing reduction air‐sea heat fluxes. Wave has slightly effect than when is...

Abstract This study used the ERA‐5 40‐year reanalysis data set from European Centre for Medium‐Range Weather Forecasts to analyze spatial characteristics of wind waves and swells in Indian Ocean. Although Southern Ocean can propagate into Bay Bengal, zonal surface Stokes drift has been shown correlate well with waves. Investigation relationship between Dipole (IOD) revealed strong correlation tropical The plays a positive role maintaining sea temperature stability by transporting more (less)...

Surface waves perform a crucial role in modulating tropical cyclone (TC) systems and have proved to be key for numerical TC predictions. In this study, we investigate the effects of wave-induced mixing wave-affected surface exchange coefficients using coupled ocean–atmosphere–wave model two real cases: Shanshan (2018) Megi (2010). The results demonstrate that enhance air–sea heat fluxes significantly positive effect on simulated intensity, size, strengthening process. contrast, has negative...