Regional Assessment of COCTS HY1-C/D Chlorophyll-a and Suspended Particulate Matter Standard Products over French Coastal Waters
Chlorophyll-a (Chla) and suspended particulate matter (SPM) are key indicators of water quality, playing critical roles in understanding marine biogeochemical processes and ecosystem health. Although satellite data from the Chinese Ocean Color and Temperature Scanner (COCTS) onboard the Haiyang-1C/D...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-07-01
|
| Series: | Remote Sensing |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2072-4292/17/14/2516 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849251778686615552 |
|---|---|
| author | Corentin Subirade Cédric Jamet Bing Han |
| author_facet | Corentin Subirade Cédric Jamet Bing Han |
| author_sort | Corentin Subirade |
| collection | DOAJ |
| description | Chlorophyll-a (Chla) and suspended particulate matter (SPM) are key indicators of water quality, playing critical roles in understanding marine biogeochemical processes and ecosystem health. Although satellite data from the Chinese Ocean Color and Temperature Scanner (COCTS) onboard the Haiyang-1C/D satellites is freely available, there has been limited validation of its standard Chla and SPM products. This study is a first step to address this gap by evaluating COCTS-derived Chla and SPM products against in situ measurements in French coastal waters. The matchup analysis showed robust performance for the Chla product, with a median symmetric accuracy (MSA) of 50.46% over a dynamic range of 0.13–4.31 mg·m<sup>−3</sup> (n = 24, Bias = 41.11%, Slope = 0.93). In contrast, the SPM product showed significant limitations, particularly in turbid waters, despite a reasonable performance in the matchup exercise, with an MSA of 45.86% within a range of 0.18–10.52 g·m<sup>−3</sup> (n = 23, Bias = −14.59%, Slope = 2.29). A comparison with another SPM model and Moderate Resolution Imaging Spectroradiometer (MODIS) products showed that the COCTS standard algorithm tends to overestimate SPM and suggests that the issue does not originate from the input radiometric data. This study provides the first regional assessment of COCTS Chla and SPM products in European coastal waters. The findings highlight the need for algorithm refinement to improve the reliability of COCTS SPM products, while the Chla product demonstrates suitability for water quality monitoring in low to moderate Chla concentrations. Future studies should focus on the validation of COCTS ocean color products in more diverse waters. |
| format | Article |
| id | doaj-art-7aee83c9cf6e4af7928edee5b127373c |
| institution | Kabale University |
| issn | 2072-4292 |
| language | English |
| publishDate | 2025-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj-art-7aee83c9cf6e4af7928edee5b127373c2025-08-20T03:56:49ZengMDPI AGRemote Sensing2072-42922025-07-011714251610.3390/rs17142516Regional Assessment of COCTS HY1-C/D Chlorophyll-a and Suspended Particulate Matter Standard Products over French Coastal WatersCorentin Subirade0Cédric Jamet1Bing Han2University Littoral Côte d’Opale, LOG UMR 8187, CNRS, IRD, University Lille, 62930 Wimereux, FranceUniversity Littoral Côte d’Opale, LOG UMR 8187, CNRS, IRD, University Lille, 62930 Wimereux, FranceNational Ocean Technology Center (NOTC), 219 Jieyuanxi Rd., Tianjin 300112, ChinaChlorophyll-a (Chla) and suspended particulate matter (SPM) are key indicators of water quality, playing critical roles in understanding marine biogeochemical processes and ecosystem health. Although satellite data from the Chinese Ocean Color and Temperature Scanner (COCTS) onboard the Haiyang-1C/D satellites is freely available, there has been limited validation of its standard Chla and SPM products. This study is a first step to address this gap by evaluating COCTS-derived Chla and SPM products against in situ measurements in French coastal waters. The matchup analysis showed robust performance for the Chla product, with a median symmetric accuracy (MSA) of 50.46% over a dynamic range of 0.13–4.31 mg·m<sup>−3</sup> (n = 24, Bias = 41.11%, Slope = 0.93). In contrast, the SPM product showed significant limitations, particularly in turbid waters, despite a reasonable performance in the matchup exercise, with an MSA of 45.86% within a range of 0.18–10.52 g·m<sup>−3</sup> (n = 23, Bias = −14.59%, Slope = 2.29). A comparison with another SPM model and Moderate Resolution Imaging Spectroradiometer (MODIS) products showed that the COCTS standard algorithm tends to overestimate SPM and suggests that the issue does not originate from the input radiometric data. This study provides the first regional assessment of COCTS Chla and SPM products in European coastal waters. The findings highlight the need for algorithm refinement to improve the reliability of COCTS SPM products, while the Chla product demonstrates suitability for water quality monitoring in low to moderate Chla concentrations. Future studies should focus on the validation of COCTS ocean color products in more diverse waters.https://www.mdpi.com/2072-4292/17/14/2516ocean colorradiometrywater qualitycoastal waterssuspended particulate matterchlorophyll-a |
| spellingShingle | Corentin Subirade Cédric Jamet Bing Han Regional Assessment of COCTS HY1-C/D Chlorophyll-a and Suspended Particulate Matter Standard Products over French Coastal Waters Remote Sensing ocean color radiometry water quality coastal waters suspended particulate matter chlorophyll-a |
| title | Regional Assessment of COCTS HY1-C/D Chlorophyll-a and Suspended Particulate Matter Standard Products over French Coastal Waters |
| title_full | Regional Assessment of COCTS HY1-C/D Chlorophyll-a and Suspended Particulate Matter Standard Products over French Coastal Waters |
| title_fullStr | Regional Assessment of COCTS HY1-C/D Chlorophyll-a and Suspended Particulate Matter Standard Products over French Coastal Waters |
| title_full_unstemmed | Regional Assessment of COCTS HY1-C/D Chlorophyll-a and Suspended Particulate Matter Standard Products over French Coastal Waters |
| title_short | Regional Assessment of COCTS HY1-C/D Chlorophyll-a and Suspended Particulate Matter Standard Products over French Coastal Waters |
| title_sort | regional assessment of cocts hy1 c d chlorophyll a and suspended particulate matter standard products over french coastal waters |
| topic | ocean color radiometry water quality coastal waters suspended particulate matter chlorophyll-a |
| url | https://www.mdpi.com/2072-4292/17/14/2516 |
| work_keys_str_mv | AT corentinsubirade regionalassessmentofcoctshy1cdchlorophyllaandsuspendedparticulatematterstandardproductsoverfrenchcoastalwaters AT cedricjamet regionalassessmentofcoctshy1cdchlorophyllaandsuspendedparticulatematterstandardproductsoverfrenchcoastalwaters AT binghan regionalassessmentofcoctshy1cdchlorophyllaandsuspendedparticulatematterstandardproductsoverfrenchcoastalwaters |