{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:12:22Z","timestamp":1760235142109,"version":"build-2065373602"},"reference-count":55,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2021,7,20]],"date-time":"2021-07-20T00:00:00Z","timestamp":1626739200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000844","name":"European Space Agency","doi-asserted-by":"publisher","award":["4000123663\/18\/I-NB","4000121621\/ 17\/1-NB"],"award-info":[{"award-number":["4000123663\/18\/I-NB","4000121621\/ 17\/1-NB"]}],"id":[{"id":"10.13039\/501100000844","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Key Research and Development Programme of China","award":["2016YFA0600102","2018YFC1407203"],"award-info":[{"award-number":["2016YFA0600102","2018YFC1407203"]}]},{"name":"National Nature Science Foundation of China","award":["41976173"],"award-info":[{"award-number":["41976173"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This paper provides an overview of the Dragon 4 project dealing with operational monitoring of sea ice and sea surface salinity (SSS) and new product developments for altimetry data. To improve sea ice thickness retrieval, a new method was developed to match the Cryosat-2 radar waveform. Additionally, an automated sea ice drift detection scheme was developed and tested on Sentinel-1 data, and the sea ice drifty capability of Gaofen-4 geostationary optical data was evaluated. A second topic included implementation and validation of a prototype of a Fully-Focussed SAR processor adapted for Sentinel-3 and Sentinel-6 altimeters and evaluation of its performance with Sentinel-3 data over the Yellow Sea; the assessment of sea surface height (SSH), significant wave height (SWH), and wind speed measurements using different altimeters and CFOSAT SWIM; and the fusion of SSH measurements in mapping sea level anomaly (SLA) data to detect mesoscale eddies. Thirdly, the investigations on the retrieval of SSS include simulations to analyse the performances of the Chinese payload configurations of the Interferometric Microwave Radiometer and the Microwave Imager Combined Active and Passive, SSS retrieval under rain conditions, and the combination of active and passive microwave to study extreme winds.<\/jats:p>","DOI":"10.3390\/rs13142847","type":"journal-article","created":{"date-parts":[[2021,7,20]],"date-time":"2021-07-20T23:19:51Z","timestamp":1626823191000},"page":"2847","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Results of the Dragon 4 Project on New Ocean Remote Sensing Data for Operational Applications"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0747-1481","authenticated-orcid":false,"given":"Ferran","family":"Gibert","sequence":"first","affiliation":[{"name":"isardSAT SL, Parc Tecnol\u00f2gic Barcelona Activa, Carrer de Marie Curie 8, 08042 Barcelona, Catalonia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2845-4912","authenticated-orcid":false,"given":"Jacqueline","family":"Boutin","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Oc\u00e9anographie et du Climat: Exp\u00e9rimentations et Approches Num\u00e9riques LOCEAN IPSLCNRS, IRD, MNHN, UMR 7159, Sorbonne Universit\u00e9, 75005 Paris, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5031-648X","authenticated-orcid":false,"given":"Wolfgang","family":"Dierking","sequence":"additional","affiliation":[{"name":"Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany"},{"name":"Centre for Integrated Remote Sensing and Forecasting for Arctic Operations, The Arctic University of Norway, 9019 Troms\u00f8, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3749-2451","authenticated-orcid":false,"given":"Alba","family":"Granados","sequence":"additional","affiliation":[{"name":"isardSAT SL, Parc Tecnol\u00f2gic Barcelona Activa, Carrer de Marie Curie 8, 08042 Barcelona, Catalonia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yan","family":"Li","sequence":"additional","affiliation":[{"name":"Marine Department, Piesat Information Technology Co., Ltd., Beijing 100080, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0393-0302","authenticated-orcid":false,"given":"Eduard","family":"Makhoul","sequence":"additional","affiliation":[{"name":"isardSAT SL, Parc Tecnol\u00f2gic Barcelona Activa, Carrer de Marie Curie 8, 08042 Barcelona, Catalonia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Junmin","family":"Meng","sequence":"additional","affiliation":[{"name":"First Institute of Oceanography, Ministry of Natural Resources of China, Qingdao 266061, China"},{"name":"Technology Innovation Center for Ocean Telemetry, Ministry of Natural Resources of China, Qingdao 266061, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexandre","family":"Supply","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Oc\u00e9anographie et du Climat: Exp\u00e9rimentations et Approches Num\u00e9riques LOCEAN IPSLCNRS, IRD, MNHN, UMR 7159, Sorbonne Universit\u00e9, 75005 Paris, France"},{"name":"LOPS Laboratory, IUEM, UBO\u2013CNRS\u2013IRD\u2013Ifremer, University of Brest, 29280 Plouzan\u00e9, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ester","family":"Vendrell","sequence":"additional","affiliation":[{"name":"isardSAT SL, Parc Tecnol\u00f2gic Barcelona Activa, Carrer de Marie Curie 8, 08042 Barcelona, Catalonia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jean-Luc","family":"Vergely","sequence":"additional","affiliation":[{"name":"ACRI-st, 78280 Guyancourt, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jin","family":"Wang","sequence":"additional","affiliation":[{"name":"Center for Marine Observation and Communications, Qingdao University, Qingdao 266000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0233-750X","authenticated-orcid":false,"given":"Jungang","family":"Yang","sequence":"additional","affiliation":[{"name":"First Institute of Oceanography, Ministry of Natural Resources of China, Qingdao 266061, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kunsheng","family":"Xiang","sequence":"additional","affiliation":[{"name":"Marine Department, Piesat Information Technology Co., Ltd., Beijing 100080, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaobin","family":"Yin","sequence":"additional","affiliation":[{"name":"College of Marine Technology, Faculty of Information Science and Engineering, Ocean University of China, Qingdao 266100, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xi","family":"Zhang","sequence":"additional","affiliation":[{"name":"First Institute of Oceanography, Ministry of Natural Resources of China, Qingdao 266061, China"},{"name":"Technology Innovation Center for Ocean Telemetry, Ministry of Natural Resources of China, Qingdao 266061, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Shen, X., Simil\u00e4, M., Dierking, W., Zhang, X., Ke, C., Liu, M., and Wang, M. (2019). A New Retracking Algorithm for Retrieving Sea Ice Freeboard from CryoSat-2 Radar Altimeter Data during Winter\u2013Spring Transition. Remote Sens., 11.","DOI":"10.3390\/rs11101194"},{"key":"ref_2","unstructured":"Zhang, X., Zhang, J., and Meng, J. (2016, January 4\u20138). Techniques for Sea Ice Characteristics Extraction and Sea Ice Monitoring Using Multi-Sensor Satellite Data in the Bohai Sea-Dragon 3 Programme Final Report (2012\u20132016). Proceedings of the Dragon 3 Final Results and Dragon 4 Kick-Off Symposium, Wuhan, China."},{"key":"ref_3","unstructured":"Garcia-Mond\u00e9jar, A., Mart\u00ednez, B., Gao, Q., Escorihuela, M.J., Garc\u00eda, P., Yang, J., and Liao, J. (2016, January 4\u20138). Measuring the Lake Level Evolution in the Qinghai-Tibet Plateau with Radar Altimeters. Proceedings of the Dragon 3 Final Results and Dragon 4 Kick-Off Symposium, Wuhan, China."},{"key":"ref_4","unstructured":"Dierking, W., Ji, Y., and Simil\u00e4, M. (2010, January 17\u201321). The Dragon-2 Sea Ice Project: Overview and Status after Two Years. Proceedings of the Dragon-2 Mid-Term Results Symposium 2008\u20132010, Guiling, China."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"841","DOI":"10.1016\/j.asr.2005.07.027","article-title":"CryoSat: A mission to determine the fluctuations in Earth\u2019s land and marine ice fields","volume":"37","author":"Wingham","year":"2006","journal-title":"Adv. Space Res."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.rse.2011.07.024","article-title":"The global monitoring for environment and security (GMES) sentinel-3 mission","volume":"120","author":"Donlon","year":"2012","journal-title":"Remote Sens. Environ."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"112395","DOI":"10.1016\/j.rse.2021.112395","article-title":"The Copernicus Sentinel-6 mission: Enhanced continuity of satellite sea level measurements from space","volume":"258","author":"Donlon","year":"2021","journal-title":"Remote Sens. Environ."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1578","DOI":"10.1109\/36.718861","article-title":"The delay\/Doppler radar altimeter","volume":"36","author":"Raney","year":"1998","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Makhoul, E., Roca, M., Ray, C., Escol\u00e0, R., and Garcia-Mond\u00e9jar, A. (2018). Evaluation of the precision of different Delay-Doppler Processor (DDP) algorithms using CryoSat-2 data over open ocean. Adv. Space Res.","DOI":"10.1016\/j.asr.2018.04.004"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Egido, A., and Smith, W. (2017). Fully Focused SAR Altimetry: Theory and Applications. IEEE Trans. Geosci. Remote Sens., 1\u201315.","DOI":"10.1109\/TGRS.2016.2607122"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Guccione, P., Scagliola, M., and Giudici, D. (2018). 2D Frequency Domain Fully Focused SAR Processing for High PRF Radar Altimeters. Remote Sens., 10.","DOI":"10.3390\/rs10121943"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"111589","DOI":"10.1016\/j.rse.2019.111589","article-title":"The performance of CryoSat-2 fully-focussed SAR for inland water-level estimation","volume":"237","author":"Kleinherenbrink","year":"2020","journal-title":"Remote Sens. Environ."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"111769","DOI":"10.1016\/j.rse.2020.111769","article-title":"Sea surface salinity estimates from spaceborne L-band radiometers: An overview of the first decade of observation (2010\u20132019)","volume":"242","author":"Reul","year":"2020","journal-title":"Remote Sens. Environ."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1391","DOI":"10.1175\/BAMS-D-15-00032.1","article-title":"Satellite and In Situ Salinity: Understanding Near-Surface Stratification and Subfootprint Variability","volume":"97","author":"Boutin","year":"2016","journal-title":"Bull. Am. Meteorol. Soc."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"274","DOI":"10.1016\/j.rse.2016.03.011","article-title":"A revised L-band radio-brightness sensitivity to extreme winds under tropical cyclones: The five year SMOS-storm database","volume":"180","author":"Reul","year":"2016","journal-title":"Remote Sens. Environ."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"C2","DOI":"10.1029\/2011JC007474","article-title":"SMOS satellite L-band radiometer: A new capability for ocean surface remote sensing in hurricanes","volume":"117","author":"Reul","year":"2012","journal-title":"J. Geophys. Res. Oceans"},{"key":"ref_17","unstructured":"(2021, July 01). ASCAT Wind Product User Manual, Ocean and Sea Ice SAF, EUMETSAT Advanced Retransmission Service, Version 1.16. Available online: https:\/\/scatterometer.knmi.nl\/publications\/pdf\/ASCAT_Product_Manual.pdf."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Torres, R., Snoeij, P.M., Davidson, M., Bibby, D., and Lokas, S. (2012, January 22\u201327). The Sentinel-1 mission and its application capabilities. Proceedings of the IEEE International Geoscience and Remote Sensing Symposium, Munich, Germany.","DOI":"10.1109\/IGARSS.2012.6351196"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"666","DOI":"10.1109\/JPROC.2010.2043032","article-title":"The SMOS Mission: New Tool for Monitoring Key Elements ofthe Global Water Cycle","volume":"98","author":"Kerr","year":"2010","journal-title":"Proc. IEEE"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1080\/10095020.2020.1838957","article-title":"China\u2019s high-resolution optical remotesensing satellites and their mapping applications","volume":"24","author":"Li","year":"2021","journal-title":"Geospat. Inf. Sci."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Sun, J., Yu, W., and Deng, Y. (2017). The SAR Payload Design and Performance for the GF-3 Mission. Sensors, 17.","DOI":"10.3390\/s17102419"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1109\/LGRS.2017.2768331","article-title":"Super-Resolution for GaoFen-4 Remote Sensing Images","volume":"15","author":"Li","year":"2018","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"90","DOI":"10.1016\/j.asr.2014.09.034","article-title":"First accuracy assessment of the HY-2A altimeter sea surface height observations: Cross-calibration results","volume":"55","author":"Bao","year":"2015","journal-title":"Adv. Space Res."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Ma, C., Zhou, W., Yin, X., Yu, R., Diao, N., and Wang, S. (August, January 28). Comparisons between HY-2B SMR and GMI brightness temperature from 6 To 37 GHz over the ocean. Proceedings of the IGARSS 2019\u2014IEEE International Geoscience and Remote Sensing Symposium, Yokohama, Japan.","DOI":"10.1109\/IGARSS.2019.8900439"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/j.srt.2019.11.012","article-title":"CFOSAT: A new mission in orbit to observe simultaneously wind and waves at the ocean surface","volume":"206","author":"Hauser","year":"2019","journal-title":"Space Res. Today"},{"key":"ref_26","unstructured":"Huffman, G.J. (2018). GPM IMERG Final Precipitation L3 Half Hourly 0.1 Degree x 0.1 Degree V05B, Goddard Earth Sciences Data and Information Services Center (GESDISC)."},{"key":"ref_27","unstructured":"Silva, J., Parisot, P., Vaze, P., and Zaouche, G. (2021, July 01). Jason-3 Mission Overview. Presentation in OSTST 2016. Available online: https:\/\/meetings.aviso.altimetry.fr\/fileadmin\/user_upload\/tx_ausyclsseminar\/files\/OPEN_05_OSTST_2016_Jason-3_status_gzaouche_v1-0_9h55.pdf."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1660","DOI":"10.1175\/BAMS-D-16-0052.1","article-title":"Capability of the SMAP Mission to Measure Ocean Surface Winds in Storms","volume":"98","author":"Meissner","year":"2017","journal-title":"Bull. Am. Meteorol. Soc."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1305","DOI":"10.1175\/JCLI-D-15-0028.1","article-title":"In Situ\u2013Based Reanalysis of the Global Ocean Temperature and Salinity with ISAS: Variability of the Heat Content and Steric Height","volume":"29","author":"Gaillard","year":"2016","journal-title":"J. Clim."},{"key":"ref_30","unstructured":"Kolodziejczyk, N., Prigent-Mazella, A., and Gaillard, F. (2017). ISAS-15 temperature and salinity gridded fields. SEANOE."},{"key":"ref_31","unstructured":"National Data Buoy Center (NDBC) Stennis Space Center (2021, July 01). NDBC Web Data Guide, Available online: https:\/\/www.ndbc.noaa.gov\/docs\/ndbc_web_data_guide.pdf."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"2789","DOI":"10.1080\/01431161.2019.1698078","article-title":"A comparison of Arctic sea ice freeboard products from Sentinel-3A and CryoSat-2 data","volume":"41","author":"Shen","year":"2020","journal-title":"Int. J. Remote Sens."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Lohse, J., Doulgeris, A., and Dierking, W. (2019). An Optimal Decision-Tree Design Strategy and Its Application to Sea Ice Classification from SAR Imagery. Remote Sens., 11.","DOI":"10.3390\/rs11131574"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Lohse, J., Doulgeris, A., and Dierking, W. (2020). Mapping sea-ice types from Sentinel-1 considering the surface- type dependent effect of incidence angle. Ann. Glaciol., 1\u201311.","DOI":"10.1017\/aog.2020.45"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Griebel, J., and Dierking, W. (2018). Impact of sea ice drift retrieval errors, discretization and grid type on calculations of sea ice deformation. Remote Sens., 10.","DOI":"10.3390\/rs10030393"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2999","DOI":"10.5194\/tc-14-2999-2020","article-title":"Estimating statistical errors in retrievals of ice velocity and deformation parameters from satellite images and buoy arrays","volume":"14","author":"Dierking","year":"2020","journal-title":"Cryosphere"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"113","DOI":"10.2112\/SI102-015.1","article-title":"An Algorithm for Sea Ice Drift Retrieval Based on Trend of Ice Drift Constraints from Sentinel-1 SAR Data","volume":"102","author":"Zhang","year":"2020","journal-title":"J. Coast. Res."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"7486","DOI":"10.1080\/01431161.2020.1760396","article-title":"Combined pattern matching and feature tracking for Bohai Sea ice drift detection using Gaofen-4 imagery","volume":"41","author":"Wang","year":"2020","journal-title":"Int. J. Remote Sens."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Liang, G., Yang, J., and Wang, J. (2021). Accuracy Evaluation of CFOSAT SWIM L2 Products Based on NDBC Buoy and Jason-3 Altimeter Data. Remote Sens., 13.","DOI":"10.3390\/rs13050887"},{"key":"ref_40","first-page":"56","article-title":"Primary Analysis of Oceanic Mesoscale Eddies Observation Abilities by Sentinel-3A SRAL","volume":"4","author":"Yang","year":"2021","journal-title":"J. Geod. Geoinf. Sci."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"632","DOI":"10.1080\/01490419.2018.1529643","article-title":"Improvement of Sea Surface Height Measurements of HY-2A Satellite Altimeter Using Jason-2","volume":"41","author":"Cui","year":"2018","journal-title":"Mar. Geod."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"522","DOI":"10.1175\/1520-0426(1998)015<0522:AIMMOM>2.0.CO;2","article-title":"An Improved Mapping Method of Multisatellite Altimeter Data","volume":"15","author":"Nadal","year":"1998","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"911","DOI":"10.1109\/TGRS.2014.2330423","article-title":"SAR altimeter backscattered waveform model","volume":"53","author":"Ray","year":"2015","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Levizzani, V., Kidd, C., Kirschbaum, D., Kummerow, C., Nakamura, K., and Turk, F. (2020). Variability of Satellite Sea Surface Salinity under Rainfall. Satellite Precipitation Measurement. Advances in Global Change Research, Springer.","DOI":"10.1007\/978-3-030-24568-9"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1016\/j.eij.2015.05.001","article-title":"Data fitting by G1 rational cubic B\u00e9zier curves using harmony search","volume":"16","author":"Mohamed","year":"2015","journal-title":"Egypt. Inform. J."},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Yang, J., Zhang, J., Jia, Y., Fan, C., and Cui, W. (2020). Validation of Sentinel-3A\/3B and Jason-3 Altimeter Wind Speeds and Significant Wave Heights Using Buoy and ASCAT Data. Remote Sens., 12.","DOI":"10.3390\/rs12132079"},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Yang, J., Zhang, J., and Wang, C. (2019). Sentinel-3A SRAL Global Statistical Assessment and Cross-Calibration with Jason-3. Remote Sens., 11.","DOI":"10.3390\/rs11131573"},{"key":"ref_48","doi-asserted-by":"crossref","unstructured":"Jia, Y., Yang, J., Lin, M., Zhang, Y., Ma, C., and Fan, C. (2020). Global Assessments of the HY-2B Measurements and Cross-Calibrations with Jason-3. Remote Sens., 12.","DOI":"10.3390\/rs12152470"},{"key":"ref_49","doi-asserted-by":"crossref","unstructured":"Mulet, S., Rio, M.-H., Etienne, H., Dibarboure, G., and Picot, N. (2021, July 01). The New CNES-CLS18 Mean Dynamic Topography. OceanPredict\u201919. Available online: https:\/\/www.godae.org\/~godae-data\/OP19\/posters\/P9-Poster_MDT18.pdf.","DOI":"10.5194\/os-2020-117"},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Mertikas, S., Tripolitsiotis, A., Donlon, C., Mavrocordatos, C., Femenias, P., Borde, F., Frantzis, X., Kokolakis, K., Guinle, T., and Tziavos, I. (2020). The ESA Permanent Facility for Altimetry Calibration: Monitoring Performance of Radar Altimeters for Sentinel-3A, Sentinel-3B and Jason-3 Using Transponder and Sea-Surface Calibrations with FRM Standards. Remote Sens., 12.","DOI":"10.3390\/rs12162642"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"1671","DOI":"10.1109\/TGRS.2014.2331193","article-title":"Waveform Aliasing in Satellite Radar Altimetry","volume":"53","author":"Smith","year":"2015","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1002\/qj.3110","article-title":"Precipitation Estimates from SMOS Sea-Surface Salinity","volume":"144","author":"Supply","year":"2018","journal-title":"Q. J. R. Meteorol. Soc."},{"key":"ref_53","doi-asserted-by":"crossref","unstructured":"Reverdin, G., Supply, A., Drushka, K., Thompson, E.J., Asher, W.E., and Louren\u00e7o, A. (2020). Intense and Small Freshwater Pools from Rainfall Investigated During Spurs-2 on 9 November 2017 in the Eastern Tropical Pacific. J. Geophys. Res. Oceans, 125.","DOI":"10.1029\/2019JC015558"},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Kyla, D., William, E.A., Andrew, T.J., Elizabeth, J.T., Suneil, I., and Clark, D. (2019). Capturing Fresh Layers with the Surface Salinity Profiler. Oceanography, 32.","DOI":"10.5670\/oceanog.2019.215"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"112027","DOI":"10.1016\/j.rse.2020.112027","article-title":"New insights into SMOS sea surface salinity retrievals in the Arctic Ocean","volume":"249","author":"Supply","year":"2020","journal-title":"Remote Sens. Environ."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/13\/14\/2847\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:32:31Z","timestamp":1760164351000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/13\/14\/2847"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,7,20]]},"references-count":55,"journal-issue":{"issue":"14","published-online":{"date-parts":[[2021,7]]}},"alternative-id":["rs13142847"],"URL":"https:\/\/doi.org\/10.3390\/rs13142847","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2021,7,20]]}}}