{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:36:25Z","timestamp":1760232985490,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2022,12,9]],"date-time":"2022-12-09T00:00:00Z","timestamp":1670544000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Construction and Application of Natural Resource Satellite Remote Sensing Technology System","award":["121157000000190004"],"award-info":[{"award-number":["121157000000190004"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The Wanshan calibration site (WSCS) is the first in-situ field for calibration and validation (Cal\/Val) of HY-2 satellite series in China. It was built in December, 2018 and began business operation in 2020. In order to define an accurate datum for Cal\/Val of altimeters, the permanent GNSS station (PGS) data of the WSCS observed on Zhiwan (ZWAN) and Wailingding (WLDD) islands were processed using GAMIT\/GLOBK software in a regional solution, combined with 61 GNSS stations distributed nearby, collected from the GNSS Research Center, Wuhan University (GRC). The Hector software was used to analyze the trend of North (N), East (E), and Up (U) directions using six different noise models with criteria of maximum likelihood estimation (MLE), Akaike Information Criteria (AIC), and the Bayesian Information Criteria (BIC). We found that the favorite noise models were white noise plus generalized Gauss\u2013Markov noise (WN + GGM), followed by generalized Gauss\u2013Markov noise (GGM). Then, we compared the PGS velocities of each direction with the Scripps Orbit and Permanent Array Center (SOPAC) output parameters and found that there was good agreement between them. The PGSs in the WSCS had velocities in the N, E, and U directions of \u221210.20 \u00b1 0.39 mm\/year, 31.09 \u00b1 0.36 mm\/year, and \u22122.24 \u00b1 0.66 mm\/year for WLDD, and \u221210.85 \u00b1 0.38 mm\/year, 30.67 \u00b1 0.30 mm\/year, and \u22123.81 \u00b1 0.66 mm\/year for ZWAN, respectively. The accurate datum was defined for Cal\/Val of altimeters for WSCS as a professional in-situ site. Moreover, the zenith wet delay (ZWD) of the coastal PGSs in the regional and sub-regional solutions was calculated and used to validate the microwave radiometers (MWRs) of Jason-3, Haiyang-2B (HY-2B), and Haiyang-2C (HY-2C). A sub-regional PGS solution was processed using 19 continuous operational reference stations (CORS) of Hong Kong Geodetic Survey Services to derive the ZWD and validate the MWRs of the altimeters. The ZWD of the PGSs were compared with the radiosonde-derived data in the regional and sub-regional solutions. The difference between them was \u22127.72~2.79 mm with an RMS of 14.53~18.62 mm, which showed good consistency between the two. Then, the PGSs\u2019 ZWD was used to validate the MWRs. To reduce the land contamination of the MWR, we determined validation distances of 6~30 km, 16~28 km, and 18~30 km for Jason-3, HY-2B, and HY-2C, respectively. The ZWD differences between PGSs and the Jason-3, HY-2B, and HY-2C altimeters were \u22122.30 \u00b1 16.13 mm, 9.22 \u00b1 22.73 mm, and \u22123.02 \u00b1 22.07 mm, respectively.<\/jats:p>","DOI":"10.3390\/rs14246235","type":"journal-article","created":{"date-parts":[[2022,12,9]],"date-time":"2022-12-09T03:59:46Z","timestamp":1670558386000},"page":"6235","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["GNSS Data Processing and Validation of the Altimeter Zenith Wet Delay around the Wanshan Calibration Site"],"prefix":"10.3390","volume":"14","author":[{"given":"Wanlin","family":"Zhai","sequence":"first","affiliation":[{"name":"National Ocean Technology Center, Tianjin 300112, China"},{"name":"Key Laboratory of Ocean Observation Technology, Ministry of Natural Resources, Tianjin 300112, China"}]},{"given":"Jianhua","family":"Zhu","sequence":"additional","affiliation":[{"name":"National Ocean Technology Center, Tianjin 300112, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5468-1591","authenticated-orcid":false,"given":"Mingsen","family":"Lin","sequence":"additional","affiliation":[{"name":"National Satellite Ocean Application Service, Beijing 100081, China"}]},{"given":"Chaofei","family":"Ma","sequence":"additional","affiliation":[{"name":"National Satellite Ocean Application Service, Beijing 100081, China"}]},{"given":"Chuntao","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Ocean, Yantai University, Yantai 266004, China"}]},{"given":"Xiaoqi","family":"Huang","sequence":"additional","affiliation":[{"name":"National Ocean Technology Center, Tianjin 300112, China"},{"name":"Key Laboratory of Ocean Observation Technology, Ministry of Natural Resources, Tianjin 300112, China"}]},{"given":"Yufei","family":"Zhang","sequence":"additional","affiliation":[{"name":"National Satellite Ocean Application Service, Beijing 100081, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1034-3176","authenticated-orcid":false,"given":"Wu","family":"Zhou","sequence":"additional","affiliation":[{"name":"National Satellite Ocean Application Service, Beijing 100081, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4084-936X","authenticated-orcid":false,"given":"He","family":"Wang","sequence":"additional","affiliation":[{"name":"National Ocean Technology Center, Tianjin 300112, China"},{"name":"Key Laboratory of Ocean Observation Technology, Ministry of Natural Resources, Tianjin 300112, China"}]},{"given":"Longhao","family":"Yan","sequence":"additional","affiliation":[{"name":"National Ocean Technology Center, Tianjin 300112, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,9]]},"reference":[{"key":"ref_1","first-page":"8","article-title":"On the Construction of China\u2019s Ocean Satellite Radar Altimetry Calibration Site","volume":"5","author":"Jiang","year":"2016","journal-title":"Ocean Dev. Manag."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Quartly, G.D., Chen, G., Nencioli, F., Morrow, R., and Picot, N. (2021). An Overview of Requirements, Procedures and Current Advances in the Calibration\/Validation of Radar Altimeters. Remote Sens., 13.","DOI":"10.3390\/rs13010125"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1171","DOI":"10.1016\/j.asr.2019.09.049","article-title":"Corsica: A 20-Yr multi-mission absolute altimeter calibration site","volume":"68","author":"Bonnefond","year":"2021","journal-title":"Adv. Space Res."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1161","DOI":"10.1016\/j.asr.2020.08.013","article-title":"A brief history of the Harvest experiment: 1989\u20132019","volume":"68","author":"Haines","year":"2021","journal-title":"Adv. Space Res."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Mertikas, S., Tripolitsiotis, A., Donlon, C., Mavrocordatos, C., F\u00e9m\u00e9nias, P., Borde, F., Frantzis, X., Kokolakis, C., Guinle, T., and Vergos, G. (2020). The ESA Permanent Facility for altimetry calibration: Monitoring performance of radar altimeters for Sentinel3A, Sentinel-3B and Jason-3 using transponder and sea-surface calibrations with FRM standards. Remote Sens., 12.","DOI":"10.3390\/rs12162642"},{"key":"ref_6","unstructured":"Watson, C. (2005). Satellite Altimeter Calibration and Validation Using GPS Buoy Technology. [Ph.D. Thesis, University of Tasmania]."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1007\/s13131-021-1745-y","article-title":"Preliminary Calibration Results of the HY-2B Altimeter\u2019s SSH at China\u2019s Wanshan Calibration Site","volume":"40","author":"Chen","year":"2021","journal-title":"Acta Oceanol. Sin."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"100028","DOI":"10.1016\/j.eqrea.2021.100028","article-title":"Analysis of GAMIT\/GLOBK in high-precision GNSS data processing for crustal deformation","volume":"1","author":"Li","year":"2021","journal-title":"Earthq. Res. Adv."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"194","DOI":"10.1007\/s10291-003-0068-0","article-title":"MATLAB Tools for viewing GPS velocities and time-series","volume":"7","author":"Herring","year":"2003","journal-title":"GPS Solut."},{"key":"ref_10","unstructured":"Herring, T., King, R., and McClusky, S. Introduction to GAMIT\/GLOBK (Release 10.7), Massachusetts Institute of Technology. Available online: http:\/\/geoweb.mit.edu\/gg\/Intro_GG.pdf."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Li, W., Li, Z., Jiang, W., Chen, Q., Zhu, G., and Wang, J. (2022). A New Spatial Filtering Algorithm for Noisy and Missing GNSS Position Time Series Using Weighted Expectation Maximization Principal Component Analysis: A Case Study for Regional GNSS Network in Xinjiang Province. Remote Sens., 14.","DOI":"10.3390\/rs14051295"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1007\/s00190-012-0605-0","article-title":"Fast error analysis of continuous GNSS observations with missing data","volume":"87","author":"Bos","year":"2013","journal-title":"J. Geod."},{"key":"ref_13","first-page":"B01405","article-title":"Correlated errors in GPS position time series: Implications for velocity estimates","volume":"116","author":"Bouin","year":"2011","journal-title":"J. Geophys. Res."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"13452","DOI":"10.1029\/2019JB017705","article-title":"Impact of Estimating Position Offsets on the Uncertainties of GNSS Site Velocity Estimates","volume":"124","author":"Wang","year":"2019","journal-title":"J. Geophys. Res. Solid Earth"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1007\/s00190-006-0102-4","article-title":"An improved and extended GPS-derived 3D velocity field of the glacial isostatic adjustment (GIA) in Fennoscandia","volume":"81","author":"Lidberg","year":"2007","journal-title":"J. Geod."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1007\/s10291-012-0293-5","article-title":"Assessment of water vapor retrievals from a GPS receiver network","volume":"17","author":"Bonafoni","year":"2013","journal-title":"GPS Solut."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"154768","DOI":"10.1175\/1520-0450(2003)042<1547:AAVOGT>2.0.CO;2","article-title":"Accuracy and variability of GPS tropospheric delay measurements of water vapor in the western Mediterranean","volume":"42","author":"Haase","year":"2003","journal-title":"J. Appl. Meteorol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1189","DOI":"10.5194\/essd-11-1189-2019","article-title":"Uncertainty in satellite estimates of global mean sea-level changes, trend and acceleration","volume":"11","author":"Ablain","year":"2019","journal-title":"Earth Syst. Sci. Data"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2827","DOI":"10.1016\/j.asr.2020.07.033","article-title":"GNSS Assessment of Sentinel-3A ECMWF Tropospheric Delays over Inland Waters","volume":"66","author":"Pearson","year":"2020","journal-title":"Adv. Space Res."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"561","DOI":"10.1029\/2018RS006789","article-title":"Consistency evaluation of precipitable water vapor derived from ERA5, ERA-Interim, GNSS, and radiosondes over China","volume":"54","author":"Zhang","year":"2019","journal-title":"Radio Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"458","DOI":"10.1007\/s00343-020-9251-1","article-title":"Preliminary calibration results for Jason-3 and Sentinel-3 altimeters in the Wanshan Islands","volume":"39","author":"Zhai","year":"2021","journal-title":"J. Ocean. Limnol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"647583","DOI":"10.3389\/feart.2021.647583","article-title":"Cross-Calibrations of the HY-2B Altimeter Using Jason-3 Satellite During the Period of April 2019\u2013September 2020","volume":"9","author":"Wang","year":"2021","journal-title":"Front. Earth Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"3205","DOI":"10.5194\/essd-12-3205-2020","article-title":"A coastally improved global dataset of wet tropospheric corrections for satellite altimetry","volume":"12","author":"Lazaro","year":"2019","journal-title":"Earth Syst. Sci. Data"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1029\/2019RS006909","article-title":"Evaluation of spatio-temporal characteristics of different zenith tropospheric delay models in Antarctica","volume":"55","author":"Li","year":"2020","journal-title":"Radio Sci."},{"key":"ref_25","unstructured":"Nischan, T. (2016). GFZRNX\u2014RINEX GNSS Data Conversion and Manipulation Toolbox, GFZ Data Services. Version 2.0-8219."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1007\/PL00012778","article-title":"TEQC: The Multi-Purpose Toolkit for GPS\/GLONASS Data","volume":"3","author":"Estey","year":"1999","journal-title":"GPS Solut."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"759","DOI":"10.1002\/2016RG000529","article-title":"Plate Boundary Observatory and related networks: GPS data analysis methods and geodetic products","volume":"54","author":"Herring","year":"2016","journal-title":"Rev. Geophys."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"He, X., Yu, K., Montillet, J.P., Xiong, C., Lu, T., Zhou, S., Ma, X., Cui, H., and Ming, F. (2020). GNSS-TS-NRS: An Open-Source MATLAB-Based GNSS Time Series Noise Reduction Software. Remote Sens., 12.","DOI":"10.3390\/rs12213532"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1271","DOI":"10.1007\/s00190-019-01244-y","article-title":"Investigation of the noise properties at low frequencies in long GNSS time series","volume":"93","author":"He","year":"2019","journal-title":"J. Geod."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"483","DOI":"10.1007\/s00190-002-0283-4","article-title":"The effect of coloured noise on the uncertainties of rates estimated from geodetic time series","volume":"76","author":"Williams","year":"2003","journal-title":"J. Geod."},{"key":"ref_31","unstructured":"Nikolaidis, R.M. (2022). Observation of Geodetic and Seismic Deformation with the Global Positioning System. [Ph.D. Thesis, University of California]."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Xia, P., Xia, J., Ye, S., and Xu, C. (2020). A New Method for Estimating Tropospheric Zenith Wet-Component Delay of GNSS Signals from Surface Meteorology Data. Remote Sens., 12.","DOI":"10.3390\/rs12213497"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1007\/s00190-007-0170-0","article-title":"Implementation and testing of the gridded Vienna Mapping Function 1 (VMF1)","volume":"82","author":"Kouba","year":"2008","journal-title":"J. Geod."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"B02406","DOI":"10.1029\/2005JB003629","article-title":"Troposphere mapping functions for GPS and very long baseline interferometry from European Centre for Medium-Range Weather Forecasts operational analysis data","volume":"111","author":"Boehm","year":"2006","journal-title":"J. Geophys. Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1804","DOI":"10.1109\/TGRS.2018.2869258","article-title":"Independent Assessment of On-Board Microwave Radiometer Measurements in Coastal Zones Using Tropospheric Delays From GNSS","volume":"57","author":"Vieira","year":"2019","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1016\/j.geog.2014.12.006","article-title":"Crustal deformation on the Chinese mainland during 1998\u20132014 based on GPS data","volume":"6","author":"Zhao","year":"2015","journal-title":"Geod. Geodyn."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Sun, J., Yang, C., and Guo, S. (2018). HECTOR for Analysis of GPS Time Series. China Satellite Navigation Conference (CSNC) 2018 Proceedings. CSNC 2018, Springer. Lecture Notes in Electrical Engineering.","DOI":"10.1007\/978-981-13-0014-1"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"905","DOI":"10.1007\/s00190-017-1102-2","article-title":"A data-driven approach for denoising GNSS position time series","volume":"92","author":"Li","year":"2018","journal-title":"J. Geod."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1016\/j.jog.2017.01.004","article-title":"Review of current GPS methodologies for producing accurate time series and their error sources","volume":"106","author":"He","year":"2017","journal-title":"J. Geodyn."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/24\/6235\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:37:04Z","timestamp":1760146624000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/24\/6235"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,12,9]]},"references-count":39,"journal-issue":{"issue":"24","published-online":{"date-parts":[[2022,12]]}},"alternative-id":["rs14246235"],"URL":"https:\/\/doi.org\/10.3390\/rs14246235","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2022,12,9]]}}}