{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T18:30:59Z","timestamp":1776277859574,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2023,8,27]],"date-time":"2023-08-27T00:00:00Z","timestamp":1693094400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NOAA component of the NASA-NOAA Joint program","award":["NRA NNH20ZDA001N-OSTST"],"award-info":[{"award-number":["NRA NNH20ZDA001N-OSTST"]}]},{"name":"NOAA component of the NASA-NOAA Joint program","award":["NA19NES4320002"],"award-info":[{"award-number":["NA19NES4320002"]}]},{"name":"NOAA component of the NASA-NOAA Joint program","award":["ST13301CQ0050 1332KP22FNEED0042"],"award-info":[{"award-number":["ST13301CQ0050 1332KP22FNEED0042"]}]},{"name":"NOAA Product Development, Readiness, and Application (PDRA)\/Jason Program","award":["NRA NNH20ZDA001N-OSTST"],"award-info":[{"award-number":["NRA NNH20ZDA001N-OSTST"]}]},{"name":"NOAA Product Development, Readiness, and Application (PDRA)\/Jason Program","award":["NA19NES4320002"],"award-info":[{"award-number":["NA19NES4320002"]}]},{"name":"NOAA Product Development, Readiness, and Application (PDRA)\/Jason Program","award":["ST13301CQ0050 1332KP22FNEED0042"],"award-info":[{"award-number":["ST13301CQ0050 1332KP22FNEED0042"]}]},{"name":"NOAA","award":["NRA NNH20ZDA001N-OSTST"],"award-info":[{"award-number":["NRA NNH20ZDA001N-OSTST"]}]},{"name":"NOAA","award":["NA19NES4320002"],"award-info":[{"award-number":["NA19NES4320002"]}]},{"name":"NOAA","award":["ST13301CQ0050 1332KP22FNEED0042"],"award-info":[{"award-number":["ST13301CQ0050 1332KP22FNEED0042"]}]},{"name":"Ocean Surface Topography Science Team support","award":["NRA NNH20ZDA001N-OSTST"],"award-info":[{"award-number":["NRA NNH20ZDA001N-OSTST"]}]},{"name":"Ocean Surface Topography Science Team support","award":["NA19NES4320002"],"award-info":[{"award-number":["NA19NES4320002"]}]},{"name":"Ocean Surface Topography Science Team support","award":["ST13301CQ0050 1332KP22FNEED0042"],"award-info":[{"award-number":["ST13301CQ0050 1332KP22FNEED0042"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>In this study, we present an extension to existing numerical retrackers of synthetic-aperture radar (SAR) altimetry signals. To our knowledge at the time of writing this manuscript, it offers the most consistent retrieval of geophysical parameters compared to low-resolution mode (LRM) retracking results. We achieve this by additionally estimating the standard deviation of vertical wave-particle velocities \u03c3v and a new parameter ux, linked to a residual Doppler in the returned radar echoes, which can be related to wind speed and direction. Including this new parameter into the SAR stack retracker mitigates sea surface height estimation errors by up to two centimeters for Sentinel-6MF SAR mode results. Additionally, we found a closed-form equation to describe ux as a function of eastward and northward wind variables, which allows mitigating the effects of this parameter on a SAR stack within level 1B processing and generating a lookup table to correct sea surface height estimates in SAR mode. This additionally opens up the door to estimating the wind speed and direction from SAR altimetry stacks. Additionally, we discuss how this new retracker performs with respect to different planned future baseline processor changes of Sentinel-6MF, namely F09 and F10, by attempting to imitate their level 2 processing. This is achieved by processing cycles 017 to 051 (nearly a full year) of Sentinel-6MF level 1A data on a global scale. We observe that the new retracking method is, on average, more accurate with respect to LRM. However, there is a slight increase in measurement noise due to the introduction of an additional parameter. To ensure that the results of the new retracker are not biased, we retrack using both the new method and the SINCS-OV ZSK retracker on Sentinel-6MF stack data produced in a Monte Carlo simulation. We analyze the simulation results with respect to accuracy, precision, and correlations between estimated parameters. We show that the accuracy of the new retracker is better than SINCS-OV ZSK but less precise, which could be related to higher correlation coefficients\u2014especially with respect to the new parameter ux\u2014between estimated parameters.<\/jats:p>","DOI":"10.3390\/rs15174206","type":"journal-article","created":{"date-parts":[[2023,8,28]],"date-time":"2023-08-28T05:46:47Z","timestamp":1693201607000},"page":"4206","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Towards the Mitigation of Discrepancies in Sea Surface Parameters Estimated from Low- and High-Resolution Satellite Altimetry"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3736-0590","authenticated-orcid":false,"given":"Christopher K.","family":"Buchhaupt","sequence":"first","affiliation":[{"name":"Earth System Science Interdisciplinary Center, Cooperative Institute for Satellite Earth System Studies, University of Maryland, College Park, MD 20740, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1489-727X","authenticated-orcid":false,"given":"Alejandro","family":"Egido","sequence":"additional","affiliation":[{"name":"European Space Research and Technology Centre, European Space Agency, 2201 AZ Noordwijk, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4367-5457","authenticated-orcid":false,"given":"Douglas","family":"Vandemark","sequence":"additional","affiliation":[{"name":"Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, NH 03824, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8814-015X","authenticated-orcid":false,"given":"Walter H. F.","family":"Smith","sequence":"additional","affiliation":[{"name":"Center for Satellite Applications and Research, National Oceanographic and Atmospheric Administration, College Park, MD 20740, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3701-8426","authenticated-orcid":false,"given":"Luciana","family":"Fenoglio","sequence":"additional","affiliation":[{"name":"Astronomical, Physical and Mathematical Geodesy, University of Bonn, 53115 Bonn, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3425-4039","authenticated-orcid":false,"given":"Eric","family":"Leuliette","sequence":"additional","affiliation":[{"name":"Center for Satellite Applications and Research, National Oceanographic and Atmospheric Administration, College Park, MD 20740, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1109\/TAP.1977.1141536","article-title":"The average impulse response of a rough surface and its applications","volume":"25","author":"Brown","year":"1977","journal-title":"IEEE Trans. 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