{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T21:07:42Z","timestamp":1776114462438,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,7,31]],"date-time":"2022-07-31T00:00:00Z","timestamp":1659225600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["42076024"],"award-info":[{"award-number":["42076024"]}]},{"name":"National Natural Science Foundation of China","award":["41821004"],"award-info":[{"award-number":["41821004"]}]},{"name":"National Natural Science Foundation of China","award":["QDBSH202108"],"award-info":[{"award-number":["QDBSH202108"]}]},{"name":"National Natural Science Foundation of China","award":["2022M713677"],"award-info":[{"award-number":["2022M713677"]}]},{"name":"the Qingdao postdoctoral application research project","award":["42076024"],"award-info":[{"award-number":["42076024"]}]},{"name":"the Qingdao postdoctoral application research project","award":["41821004"],"award-info":[{"award-number":["41821004"]}]},{"name":"the Qingdao postdoctoral application research project","award":["QDBSH202108"],"award-info":[{"award-number":["QDBSH202108"]}]},{"name":"the Qingdao postdoctoral application research project","award":["2022M713677"],"award-info":[{"award-number":["2022M713677"]}]},{"name":"China Postdoctoral Science Foundation","award":["42076024"],"award-info":[{"award-number":["42076024"]}]},{"name":"China Postdoctoral Science Foundation","award":["41821004"],"award-info":[{"award-number":["41821004"]}]},{"name":"China Postdoctoral Science Foundation","award":["QDBSH202108"],"award-info":[{"award-number":["QDBSH202108"]}]},{"name":"China Postdoctoral Science Foundation","award":["2022M713677"],"award-info":[{"award-number":["2022M713677"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Understanding nodal tidal characteristics is essential for accurate long-term tidal prediction. Observational nodal evolution of tides is mainly based on tide gauge records in coastal areas which are limited in time and space, thus impeding coherent determinations of basin-wide patterns of tidal variability. In this paper, we indicate the potential of satellite altimeter data to investigate 18.61-year nodal modulations of main constituents in the Gulf of Tonkin. Three tide gauges and multi-source satellite altimeter observations (TOPEX\/Poseidon, Jason1, Jason2, and Jason3) revealed that 18.61-year nodal cycles in tidal amplitudes have noticeable deviations from the equilibrium tidal theory in the Gulf of Tonkin. In general, M2 and N2 nodal modulations are anomalously larger than theoretical values while K2, K1, and O1 nodal modulations are noticeably smaller than theoretical values. Compared to point-based tide gauges, satellite altimeter records can provide basin-wide features of nodal modulations of main constituents. Although overlapping geographical blocks are applied to eliminate the effect of tidal alias originated from long-period sampling intervals, the estimation of nodal cycles of minor constituents are still questionable. Nevertheless, the methods described here provide a strong foundation for future research on time-varying tidal dynamics using the combination of tide gauges and satellite altimeter data.<\/jats:p>","DOI":"10.3390\/rs14153672","type":"journal-article","created":{"date-parts":[[2022,8,1]],"date-time":"2022-08-01T04:04:00Z","timestamp":1659326640000},"page":"3672","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Anomalous 18.61-Year Nodal Cycles in the Gulf of Tonkin Revealed by Tide Gauges and Satellite Altimeter Records"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8804-7772","authenticated-orcid":false,"given":"Haidong","family":"Pan","sequence":"first","affiliation":[{"name":"First Institute of Oceanography, and Key Laboratory of Marine Science and Numerical Modeling, Ministry of Natural Resources, Qingdao 266061, China"},{"name":"Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China"},{"name":"Shandong Key Laboratory of Marine Science and Numerical Modeling, Qingdao 266061, China"},{"name":"Key Laboratory of Physical Oceanography, Ocean University of China, Qingdao 266100, China"}]},{"given":"Adam Thomas","family":"Devlin","sequence":"additional","affiliation":[{"name":"School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, China"},{"name":"Key Lab of Poyang Lake Wetland and Watershed Research of Ministry of Education, Nanchang 330022, China"},{"name":"Institute of Space and Earth Information Science, The Chinese University of Hong Kong, Shatin, Hong Kong 999077, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6181-1742","authenticated-orcid":false,"given":"Tengfei","family":"Xu","sequence":"additional","affiliation":[{"name":"First Institute of Oceanography, and Key Laboratory of Marine Science and Numerical Modeling, Ministry of Natural Resources, Qingdao 266061, China"},{"name":"Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China"},{"name":"Shandong Key Laboratory of Marine Science and Numerical Modeling, Qingdao 266061, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7994-7579","authenticated-orcid":false,"given":"Xianqing","family":"Lv","sequence":"additional","affiliation":[{"name":"Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China"},{"name":"Key Laboratory of Physical Oceanography, Ocean University of China, Qingdao 266100, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1217-6973","authenticated-orcid":false,"given":"Zexun","family":"Wei","sequence":"additional","affiliation":[{"name":"First Institute of Oceanography, and Key Laboratory of Marine Science and Numerical Modeling, Ministry of Natural Resources, Qingdao 266061, China"},{"name":"Laboratory for Regional Oceanography and Numerical Modeling, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China"},{"name":"Shandong Key Laboratory of Marine Science and Numerical Modeling, Qingdao 266061, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1215","DOI":"10.1002\/2014JC010312","article-title":"Nodal variations and long-term changes in the main tides on the coasts of China","volume":"120","author":"Feng","year":"2015","journal-title":"J. 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