{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T00:54:20Z","timestamp":1760230460386,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,7,27]],"date-time":"2022-07-27T00:00:00Z","timestamp":1658880000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["61931025","2017YFC1405600"],"award-info":[{"award-number":["61931025","2017YFC1405600"]}]},{"name":"National Key R&amp;D Program of China","award":["61931025","2017YFC1405600"],"award-info":[{"award-number":["61931025","2017YFC1405600"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Synthetic aperture radar (SAR) and wave spectrometer are common methods for observing the ocean wind field and waves on the sea surface, but both have limitations. Due to the influence of velocity bunching modulation, SAR wave observation is limited by the azimuth cut-off phenomenon. Meanwhile, SAR relies on an external wind direction source, so it is difficult for SAR to observe wind fields independently. There is no azimuthal cut-off phenomenon when the spectrometer observes the sea surface, but its azimuth resolution is much lower than SAR. Combining the above characteristics, the joint inversion of SAR and wave spectrometer for sea-state parameters becomes possible. In this paper, a joint method for wind field and wave parameter inversion combining SAR with spectrometer data is proposed. In this method for wave parameter inversion, the wave spectrum of the spectrometer was used as a first-guess spectrum of SAR wave spectrum inversion, the fit wave spectrum obtained by joint inversion and the modified wave spectrum of the spectrometer were fused to form a new spectrum, and the wave parameters were calculated. For wind field parameter inversion, wind direction was obtained using a wave spectrometer, and was used as the input of the SAR wind field inversion. Wind speed was obtained using the CMOD5.N method. Collocated data from Sentinel-1 SAR, the wave spectrometer, the National Data Buoy Center (NDBC) buoy, and the European Centre for Medium-Range Weather Forecasting (ECMWF) are used to verify the proposed method. Sea parameters retrieved from the spectrometer and SAR are compared to the buoy and ECMWF data. The results show that the root mean square errors of significant wave height, mean wave period, wind direction and wind speed are 0.37 m, 1.02 s, 22.7\u00b0 and 1.06 m\/s with ECMWF data, and 0.35 m, 0.78 s, 18.22\u00b0 and 0.92 m\/s with buoy data, respectively. By comparing the inversion results with the L2 products of SAR and SWIM, it can be concluded that the inversion accuracy of the joint method is higher in the middle and low sea conditions. Therefore, the joint inversion method for wind field and wave parameters proposed in this paper has good results, which verifies the accuracy of the joint inversion method.<\/jats:p>","DOI":"10.3390\/rs14153601","type":"journal-article","created":{"date-parts":[[2022,7,28]],"date-time":"2022-07-28T03:21:16Z","timestamp":1658978476000},"page":"3601","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Joint Method for Wave and Wind Field Parameter Inversion Combining SAR with Wave Spectrometer Data"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0839-6738","authenticated-orcid":false,"given":"Yong","family":"Wan","sequence":"first","affiliation":[{"name":"College of Oceanography and Space Informatics, China University of Petroleum, Qingdao 266580, China"}]},{"given":"Xiaona","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Oceanography and Space Informatics, China University of Petroleum, Qingdao 266580, China"}]},{"given":"Chenqing","family":"Fan","sequence":"additional","affiliation":[{"name":"Remote Sensing Office of the First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China"}]},{"given":"Ruozhao","family":"Qu","sequence":"additional","affiliation":[{"name":"College of Control Science and Engineering, China University of Petroleum, Qingdao 266580, China"}]},{"given":"Ennan","family":"Ma","sequence":"additional","affiliation":[{"name":"College of Control Science and Engineering, China University of Petroleum, Qingdao 266580, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,27]]},"reference":[{"key":"ref_1","first-page":"61","article-title":"Application of remote sensing technology in Marine disaster monitoring","volume":"6","author":"Zou","year":"2018","journal-title":"City Disaster Reduct."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"6218","DOI":"10.1109\/TGRS.2017.2723431","article-title":"An empirical mode decomposition method for sea surface wind measurements from X-band nautical radar data","volume":"55","author":"Huang","year":"2017","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_3","first-page":"16","article-title":"Sea wave spectrum inversion method based on RADARSAT-2 SAR satellite data and its sea Trial verification","volume":"39","author":"Wan","year":"2020","journal-title":"Lab. Res. Explor."},{"doi-asserted-by":"crossref","unstructured":"Huang, W.M., Liu, X.L., and Gill Eric, W. (2017). Ocean wind and wave measurements using X-Band marine radar: A comprehensive review. Remote Sens., 9.","key":"ref_4","DOI":"10.3390\/rs9121261"},{"key":"ref_5","first-page":"135","article-title":"Development status of spaceborne synthetic aperture radar","volume":"8","author":"Cheng","year":"2016","journal-title":"Electron. Meas."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"7616","DOI":"10.1002\/2015JC011275","article-title":"Estimating wave orbital velocity through the azimuth cutoff from space-Borne satellites","volume":"120","author":"Stopa","year":"2015","journal-title":"J. Geophys. Res. Ocean."},{"key":"ref_7","first-page":"7","article-title":"Simulation analysis of effective wave height inversion method of ocean spectrometer","volume":"34","author":"Han","year":"2013","journal-title":"Telem. Remote Control"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"4506305","DOI":"10.1109\/LGRS.2022.3162891","article-title":"A Joint Inversion Method of Wave and Wind Field Parameters Based on SAR SLC Data","volume":"19","author":"Wan","year":"2022","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"10713","DOI":"10.1029\/91JC00302","article-title":"On the nonlinear mapping of an ocean wave spectrum into a synthetic aperture radar image spectrum and its inversion","volume":"96","author":"Hasselmann","year":"1991","journal-title":"J. Geophys. Res. Ocean."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"3497","DOI":"10.1029\/1999JC900282","article-title":"A semiparametric algorithm to retrieve ocean wave spectra from synthetic aperture radar","volume":"105","author":"Mastenbroek","year":"2000","journal-title":"J. Geophys. Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"428","DOI":"10.1007\/BF02885970","article-title":"A Parameterized Method for Extracting Wave Direction Spectrum from Synthetic Aperture Radar","volume":"44","author":"He","year":"1999","journal-title":"Chin. Sci. Bull."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1047","DOI":"10.1109\/36.406690","article-title":"SAR-Ocean wave inversion using image cross spectra","volume":"33","author":"Engen","year":"1995","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_13","first-page":"C05004","article-title":"A parametric scheme for the retrieval of two-Dimensional ocean wave spectra from synthetic aperture radar look cross spectra","volume":"110","author":"Lehner","year":"2005","journal-title":"J. Geophys. Res. Ocean."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"987","DOI":"10.1029\/JC090iC01p00987","article-title":"Aircraft and satellite measurement of ocean wave directional spectra using scanning-beam microwave radars","volume":"90","author":"Jackson","year":"1985","journal-title":"J. Geophys. Res. Ocean."},{"key":"ref_15","first-page":"116","article-title":"The radar ocean-Wave spectrometer","volume":"8","author":"Jackson","year":"1987","journal-title":"Johns Hopkins APL Tech. Dig."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"981","DOI":"10.1109\/36.175333","article-title":"RESSAC: A new airborne FM\/CW radar ocean wave spectrometer","volume":"30","author":"Hauser","year":"1992","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"421","DOI":"10.1175\/1520-0426(2001)018<0421:SARART>2.0.CO;2","article-title":"SWIMSAT: A Real-Aperture Radar to Measure Directional Spectra of Ocean Waves from Space\u2014Main Characteristics and Performance Simulation","volume":"18","author":"Hauser","year":"2001","journal-title":"J. Atmos. Ocean. Technol."},{"doi-asserted-by":"crossref","unstructured":"Tison, C., Manent, C., Amiot, T., Enjolras, V., Hauser, D., Rey, L., and Castillan, P. (2011). Estimation of wave spectra with swim on cfosat-illustration on a real case. IEEE Int. Geosci. Remote Sens. Symp., 1473\u20131476.","key":"ref_18","DOI":"10.1109\/IGARSS.2011.6049345"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1007\/s13131-010-0046-7","article-title":"Satellite-Based RAR performance simulation for measuring directional ocean wave spectrum based on SAR inversion spectrum","volume":"29","author":"Ren","year":"2010","journal-title":"Acta Oceanol. Sin."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"847","DOI":"10.1007\/s00343-015-5043-4","article-title":"A joint method to retrieve directional ocean wave spectra from SAR and wave spectrometer data","volume":"34","author":"Ren","year":"2016","journal-title":"Chin. J. Oceanol. Limnol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"5767","DOI":"10.1029\/96JC02860","article-title":"Scatterometer data interpretation: Estimation and validation of the transfer function CMOD4","volume":"102","author":"Stoffelen","year":"1997","journal-title":"J. Geophys. Res. Ocean."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"7767","DOI":"10.1029\/97JC01911","article-title":"Observation of tropical cyclones by high-Resolution scatterometry","volume":"103","author":"Quilfen","year":"1998","journal-title":"J. Geophys. Res. Ocean."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"C03006","DOI":"10.1029\/2006JC003743","article-title":"An improved C-Band scatterometer ocean geophysical model function: CMOD5","volume":"112","author":"Hersbach","year":"2007","journal-title":"J. Geophys. Res. Ocean."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"721","DOI":"10.1175\/2009JTECHO698.1","article-title":"Comparison of C-Band scatterometer CMOD5. N equivalent neutral winds with ECMWF","volume":"27","author":"Hersbach","year":"2010","journal-title":"J. Atmos. Ocean. Technol."},{"unstructured":"Chu, X.Q. (2011). Basic Research on Wave Remote Sensing Method and Application of Wave Spectrometer. [Ph.D. Thesis, Graduate University of Chinese Academy of Sciences (Institute of Oceanography)].","key":"ref_25"},{"unstructured":"Wang, X.C. (2016). Study on Wave Spectrum Inversion Method of Airborne Spectrometer. [Master\u2019s Thesis, China University of Petroleum (East China)].","key":"ref_26"},{"unstructured":"Li, P. (2019). Inversion of Sea Surface Wind Field by Spaceborne Spectrometer. [Master\u2019s Thesis, Huazhong University of Science and Technology].","key":"ref_27"},{"key":"ref_28","first-page":"9","article-title":"Study on the accuracy of ocean wave spectrum retrieval by satellite-borne radar spectrometer","volume":"32","author":"Lin","year":"2010","journal-title":"J. Oceanogr."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"3072","DOI":"10.1016\/j.asr.2021.01.050","article-title":"Impact of rain on wave retrieval from Sentinel-1 synthetic aperture radar images in tropical cyclones","volume":"67","author":"Zhao","year":"2021","journal-title":"Adv. Space Res."},{"unstructured":"Zhang, K.Y. (2019). Sea Surface Wind Field Retrieval and Offshore Wind Energy Resource Assessment Based on C-Band SAR Data. [Ph.D. Thesis, Zhejiang University].","key":"ref_30"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"4046","DOI":"10.1080\/01431161.2014.916059","article-title":"Development of polarization ratio model for sea surface wind field retrieval from TerraSAR-X HH polarization data","volume":"35","author":"Shao","year":"2014","journal-title":"Int. J. Remote Sens."},{"unstructured":"Huang, P. (2014). Ocean Wave Detection Mechanism and Simulation Research of Ocean Spectrometer. [Master\u2019s Thesis, Huazhong University of Science and Technology].","key":"ref_32"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"169082","DOI":"10.1109\/ACCESS.2020.3023012","article-title":"Research on the Applicability of the E Spectrum and PM Spectrum as the First Guess Spectrum of SAR Wave Spectrum Inversion","volume":"8","author":"Wan","year":"2020","journal-title":"IEEE Access"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/15\/3601\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T23:57:49Z","timestamp":1760140669000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/15\/3601"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,7,27]]},"references-count":33,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2022,8]]}},"alternative-id":["rs14153601"],"URL":"https:\/\/doi.org\/10.3390\/rs14153601","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2022,7,27]]}}}