Matchup Characteristics of Sea Surface Salinity Using a High-Resolution Ocean Model
Sea surface salinity (SSS) satellite measurements are validated using in situ observations usually made by surfacing Argo floats. Validation statistics are computed using matched values of SSS from satellites and floats. This study explores how the matchup process is done using a high-resolution num...
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doaj-df15d82e225f49b0a05a0b8f7e47366f2021-08-06T15:30:45ZengMDPI AGRemote Sensing2072-42922021-07-01132995299510.3390/rs13152995Matchup Characteristics of Sea Surface Salinity Using a High-Resolution Ocean ModelFrederick M. Bingham0Severine Fournier1Susannah Brodnitz2Karly Ulfsax3Hong Zhang4Center for Marine Science, University of North Carolina Wilmington, Wilmington, NC 28403, USAJet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USACenter for Marine Science, University of North Carolina Wilmington, Wilmington, NC 28403, USACenter for Marine Science, University of North Carolina Wilmington, Wilmington, NC 28403, USAJet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USASea surface salinity (SSS) satellite measurements are validated using in situ observations usually made by surfacing Argo floats. Validation statistics are computed using matched values of SSS from satellites and floats. This study explores how the matchup process is done using a high-resolution numerical ocean model, the MITgcm. One year of model output is sampled as if the Aquarius and Soil Moisture Active Passive (SMAP) satellites flew over it and Argo floats popped up into it. Statistical measures of mismatch between satellite and float are computed, RMS difference (RMSD) and bias. The bias is small, less than 0.002 in absolute value, but negative with float values being greater than satellites. RMSD is computed using an “all salinity difference” method that averages level 2 satellite observations within a given time and space window for comparison with Argo floats. RMSD values range from 0.08 to 0.18 depending on the space–time window and the satellite. This range gives an estimate of the representation error inherent in comparing single point Argo floats to area-average satellite values. The study has implications for future SSS satellite missions and the need to specify how errors are computed to gauge the total accuracy of retrieved SSS values.https://www.mdpi.com/2072-4292/13/15/2995surface salinityocean modelingrepresentation errorsatellite validationmatchups |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Frederick M. Bingham Severine Fournier Susannah Brodnitz Karly Ulfsax Hong Zhang |
spellingShingle |
Frederick M. Bingham Severine Fournier Susannah Brodnitz Karly Ulfsax Hong Zhang Matchup Characteristics of Sea Surface Salinity Using a High-Resolution Ocean Model Remote Sensing surface salinity ocean modeling representation error satellite validation matchups |
author_facet |
Frederick M. Bingham Severine Fournier Susannah Brodnitz Karly Ulfsax Hong Zhang |
author_sort |
Frederick M. Bingham |
title |
Matchup Characteristics of Sea Surface Salinity Using a High-Resolution Ocean Model |
title_short |
Matchup Characteristics of Sea Surface Salinity Using a High-Resolution Ocean Model |
title_full |
Matchup Characteristics of Sea Surface Salinity Using a High-Resolution Ocean Model |
title_fullStr |
Matchup Characteristics of Sea Surface Salinity Using a High-Resolution Ocean Model |
title_full_unstemmed |
Matchup Characteristics of Sea Surface Salinity Using a High-Resolution Ocean Model |
title_sort |
matchup characteristics of sea surface salinity using a high-resolution ocean model |
publisher |
MDPI AG |
series |
Remote Sensing |
issn |
2072-4292 |
publishDate |
2021-07-01 |
description |
Sea surface salinity (SSS) satellite measurements are validated using in situ observations usually made by surfacing Argo floats. Validation statistics are computed using matched values of SSS from satellites and floats. This study explores how the matchup process is done using a high-resolution numerical ocean model, the MITgcm. One year of model output is sampled as if the Aquarius and Soil Moisture Active Passive (SMAP) satellites flew over it and Argo floats popped up into it. Statistical measures of mismatch between satellite and float are computed, RMS difference (RMSD) and bias. The bias is small, less than 0.002 in absolute value, but negative with float values being greater than satellites. RMSD is computed using an “all salinity difference” method that averages level 2 satellite observations within a given time and space window for comparison with Argo floats. RMSD values range from 0.08 to 0.18 depending on the space–time window and the satellite. This range gives an estimate of the representation error inherent in comparing single point Argo floats to area-average satellite values. The study has implications for future SSS satellite missions and the need to specify how errors are computed to gauge the total accuracy of retrieved SSS values. |
topic |
surface salinity ocean modeling representation error satellite validation matchups |
url |
https://www.mdpi.com/2072-4292/13/15/2995 |
work_keys_str_mv |
AT frederickmbingham matchupcharacteristicsofseasurfacesalinityusingahighresolutionoceanmodel AT severinefournier matchupcharacteristicsofseasurfacesalinityusingahighresolutionoceanmodel AT susannahbrodnitz matchupcharacteristicsofseasurfacesalinityusingahighresolutionoceanmodel AT karlyulfsax matchupcharacteristicsofseasurfacesalinityusingahighresolutionoceanmodel AT hongzhang matchupcharacteristicsofseasurfacesalinityusingahighresolutionoceanmodel |
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1721217740960694272 |