{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:33:10Z","timestamp":1760243590980,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2013,10,14]],"date-time":"2013-10-14T00:00:00Z","timestamp":1381708800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Unlike most altimetric missions, CryoSat-2 is not equipped with an onboard microwave radiometer (MWR) to provide wet tropospheric correction (WTC) to radar altimeter measurements, thus, relying on a model-based one provided by the European Center for Medium-range Weather Forecasts (ECMWF). In the ambit of ESA funded project CP4O, an improved WTC for CryoSat-2 data over ocean is under development, based on a data combination algorithm (DComb) through objective analysis of WTC values derived from all existing global-scale data types. The scope of this study is the analysis and inter-calibration of the large dataset of total column water vapor (TCWV) products from scanning MWR aboard Remote Sensing (RS) missions for use in the WTC computation for CryoSat-2. The main issues regarding the computation of the WTC from all TCWV products are discussed. The analysis of the orbital parameters of CryoSat-2 and all other considered RS missions, their sensor characteristics and inter-calibration is presented, providing an insight into the expected impact of these datasets on the WTC estimation. The most suitable approach for calculating the WTC from TCWV is investigated. For this type of application, after calibration with respect to an appropriate reference, two approaches were found to give very similar results, with root mean square differences of 2 mm.<\/jats:p>","DOI":"10.3390\/rs5104977","type":"journal-article","created":{"date-parts":[[2013,10,14]],"date-time":"2013-10-14T11:11:20Z","timestamp":1381749080000},"page":"4977-5005","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Analysis and Inter-Calibration of Wet Path Delay Datasets to Compute the Wet Tropospheric Correction for CryoSat-2 over Ocean"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0946-0092","authenticated-orcid":false,"given":"M.","family":"Fernandes","sequence":"first","affiliation":[{"name":"Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"},{"name":"Centro Interdisciplinar de Investiga\u00e7\u00e3o Marinha e Ambiental (CIIMAR\/CIMAR),  Universidade do Porto, 4050-123 Porto, Portugal"}]},{"given":"Alexandra","family":"Nunes","sequence":"additional","affiliation":[{"name":"Centro Interdisciplinar de Investiga\u00e7\u00e3o Marinha e Ambiental (CIIMAR\/CIMAR),  Universidade do Porto, 4050-123 Porto, Portugal"},{"name":"Instituto Superior de Engenharia, Instituto Polit\u00e9cnico do Porto, 4200-072 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8849-7546","authenticated-orcid":false,"given":"Clara","family":"L\u00e1zaro","sequence":"additional","affiliation":[{"name":"Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"},{"name":"Centro Interdisciplinar de Investiga\u00e7\u00e3o Marinha e Ambiental (CIIMAR\/CIMAR),  Universidade do Porto, 4050-123 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2013,10,14]]},"reference":[{"key":"ref_1","unstructured":"Cotton, D., Benveniste, J., Clarizia, M.-P., Roca, M., Gommenginger, C., Naeije, M., Labroue, S., Picot, N., Fernandes, J., and Andersen, O. (May, January 27). CryoSat Plus For Oceans: An ESA Project for CryoSat-2 Data Exploitation Over Ocean. Vienna, Austria."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"596","DOI":"10.1109\/LGRS.2010.2042425","article-title":"GNSS-Derived path delay: An approach to compute the wet tropospheric correction for coastal altimetry","volume":"7","author":"Fernandes","year":"2010","journal-title":"IEEE Geosci. Remote Sens. Lett"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1352","DOI":"10.1016\/j.asr.2012.04.025","article-title":"Tropospheric delays from GNSS for application in coastal altimetry","volume":"51","author":"Fernandes","year":"2013","journal-title":"Adv. Space Res"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3211","DOI":"10.1109\/TGRS.2011.2104967","article-title":"Using objective analysis of scanning radiometer measurements to compute the water vapor path delay for altimetry","volume":"49","author":"Stum","year":"2011","journal-title":"IEEE Trans. Geosci. Remote Sens"},{"key":"ref_5","first-page":"10","article-title":"Increased resolution in the ECMWF deterministic and ensemble prediction systems","volume":"124","author":"Miller","year":"2010","journal-title":"ECMWF Newslett"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"553","DOI":"10.1002\/qj.828","article-title":"The ERA-Interim reanalysis: configuration and performance of the data assimilation system","volume":"137","author":"Dee","year":"2011","journal-title":"Quart. J. Royal Meteorol. Soc"},{"key":"ref_7","unstructured":"Eymard, L., and Obligis, E (2006, January 13\u201318). The Altimetric Wet Troposheric Correction: Progress since the ERS-1 Mission. Venice, Italy."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1986","DOI":"10.1109\/TGRS.2009.2037220","article-title":"A novel near-land radiometer wet path-delay retrieval algorithm: Application to the Jason-2\/OSTM advanced microwave radiometer","volume":"48","author":"Brown","year":"2010","journal-title":"IEEE Trans. Geosci. Remote Sens"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1131","DOI":"10.1175\/JTECH1897.1","article-title":"Improved level-3 oceanic rainfall retrieval from dual-frequency spaceborne radar altimeter systems","volume":"23","author":"Tournadre","year":"2006","journal-title":"J.Atmos. Ocean. Technol"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1806","DOI":"10.1109\/TGRS.2008.2010130","article-title":"Cloud and rain effects on AltiKa\/SARAL Ka-band radar altimeter\u2014Part I: Modeling and mean annual data availability","volume":"47","author":"Tournadre","year":"2009","journal-title":"IEEE Trans. Geosci. Remote Sens"},{"key":"ref_11","unstructured":"Verron, J., and Steunou, N (2006, January 13\u201318). ALTIKA: A Micro-Satellite Ka-band Altimetry Mission. Venice, Italy."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"15787","DOI":"10.1029\/92JD01517","article-title":"GPS meteorology: Remote-sensing of atmospheric water-vapor using the global positioning system","volume":"97","author":"Bevis","year":"1992","journal-title":"J. Geophys. Res.-Atmos"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1109\/36.368213","article-title":"TOPEX\/Poseidon microwave radiometer (TMR), III, Wet troposphere range correction algorithm and pre-launch error budget","volume":"33","author":"Keihm","year":"1995","journal-title":"IEEE Trans. Geosci. Remote Sens"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1175\/1520-0450(1994)033<0379:GMMZWD>2.0.CO;2","article-title":"GPS meteorology\u2014Mapping zenith wet delays onto precipitable water","volume":"33","author":"Bevis","year":"1994","journal-title":"J.Appl. Meteorol"},{"key":"ref_15","unstructured":"Mendes, V.B., Prates, G., Santos, L., and Langley, R.B. (2000, January 26\u201328). An Evaluation of the Accuracy of Models of the Determination of the Weighted Mean Temperature of the Atmosphere. Anaheim, CA, USA."},{"key":"ref_16","unstructured":"Mendes, V.B. (1999). Modeling the Neutral-Atmosphere Propagation Delay in Radiometric Space Techniques. Ph.D. Dissertation, Department of Geodesy and Geomatics Engineering, University of New Brunswick, Fredericton, NB, Canada."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1029\/2005JD006215","article-title":"Global estimates of water-vapor-weighted mean temperature of the atmosphere for GPS applications","volume":"110","author":"Wang","year":"2005","journal-title":"J. Geophys. Res.-Atmos"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"21719","DOI":"10.1029\/97JD01808","article-title":"Estimating mean weighted temperature of the atmosphere for Global Positioning System applications","volume":"102","author":"Ross","year":"1997","journal-title":"J. Geophys. Res.-Atmos"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1379","DOI":"10.1109\/36.843032","article-title":"TOPEX Microwave radiometer performance evaluation, 1992\u20131998","volume":"38","author":"Keihm","year":"2000","journal-title":"IEEE Trans. Geosci. Remote Sens"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"8703","DOI":"10.1029\/96JC01751","article-title":"A well-calibrated ocean algorithm for special sensor microwave\/imager","volume":"102","author":"Wentz","year":"1997","journal-title":"J.Geophys. Res.-Ocean"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Wentz, F.J., and Meissner, T (2000). AMSR Ocean Algorithm, Version 2, Remote Sensing Systems.","DOI":"10.56236\/RSS-af"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1175\/JAM2346.1","article-title":"Rain retrieval from TMI brightness temperature measurements using a TRMM PR-based database","volume":"45","author":"Viltard","year":"2006","journal-title":"J. Appl. Meteorol. Clim"},{"key":"ref_23","unstructured":"Meissner, T., and Wentz, F (2005, January 18\u201323). Ocean Retrievals for WindSat\u2014Radiative Transfer Model, Algorithm, Validation. Washington, DC, USA."},{"key":"ref_24","unstructured":"Pampaloni, P., and Paloscia, S. (2000). Microwave Radiometry & Remote Sensing of the Earth\u2019s Surface and Atmosphere, VSP."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"5255","DOI":"10.1080\/01431160410001712981","article-title":"Equator crossing times for NOAA, ERS and EOS sun-synchronous satellites","volume":"25","author":"Ignatov","year":"2004","journal-title":"Int. J. Remote Sens"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1531","DOI":"10.1109\/TGRS.2012.2213262","article-title":"Maintaining the long-term calibration of the Jason-2\/OSTM advanced microwave radiometer through intersatellite calibration","volume":"51","author":"Brown","year":"2013","journal-title":"IEEE Trans. Geosci. Remote Sens"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"431","DOI":"10.1080\/01490419.2011.584829","article-title":"Monitoring the Jason-2\/AMR stability using SNO observations from AMSU on MetOp-A","volume":"34","author":"Cao","year":"2011","journal-title":"Mar. Geod"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/5\/10\/4977\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:49:49Z","timestamp":1760219389000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/5\/10\/4977"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2013,10,14]]},"references-count":27,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2013,10]]}},"alternative-id":["rs5104977"],"URL":"https:\/\/doi.org\/10.3390\/rs5104977","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2013,10,14]]}}}