Biogeochemical Model Optimization by Using Satellite-Derived Phytoplankton Functional Type Data and BGC-Argo Observations in the Northern South China Sea

Marine biogeochemical models have been widely used to understand ecosystem dynamics and biogeochemical cycles. To resolve more processes, models typically increase in complexity, and require optimization of more parameters. Data assimilation is an essential tool for parameter optimization, which can...

Full description

Bibliographic Details
Main Authors: Chan Shu, Peng Xiu, Xiaogang Xing, Guoqiang Qiu, Wentao Ma, Robert J. W. Brewin, Stefano Ciavatta
Format: Article
Language:English
Published: MDPI AG 2022-03-01
Series:Remote Sensing
Subjects:
Online Access:https://www.mdpi.com/2072-4292/14/5/1297
_version_ 1827650649830981632
author Chan Shu
Peng Xiu
Xiaogang Xing
Guoqiang Qiu
Wentao Ma
Robert J. W. Brewin
Stefano Ciavatta
author_facet Chan Shu
Peng Xiu
Xiaogang Xing
Guoqiang Qiu
Wentao Ma
Robert J. W. Brewin
Stefano Ciavatta
author_sort Chan Shu
collection DOAJ
description Marine biogeochemical models have been widely used to understand ecosystem dynamics and biogeochemical cycles. To resolve more processes, models typically increase in complexity, and require optimization of more parameters. Data assimilation is an essential tool for parameter optimization, which can reduce model uncertainty and improve model predictability. At present, model parameters are often adjusted using sporadic in-situ measurements or satellite-derived total chlorophyll-a concentration at sea surface. However, new ocean datasets and satellite products have become available, providing a unique opportunity to further constrain ecosystem models. Biogeochemical-Argo (BGC-Argo) floats are able to observe the ocean interior continuously and satellite phytoplankton functional type (PFT) data has the potential to optimize biogeochemical models with multiple phytoplankton species. In this study, we assess the value of assimilating BGC-Argo measurements and satellite-derived PFT data in a biogeochemical model in the northern South China Sea (SCS) by using a genetic algorithm. The assimilation of the satellite-derived PFT data was found to improve not only the modeled total chlorophyll-a concentration, but also the individual phytoplankton groups at surface. The improvement of simulated surface diatom provided a better representation of subsurface particulate organic carbon (POC). However, using satellite data alone did not improve vertical distributions of chlorophyll-a and POC. Instead, these distributions were improved by combining the satellite data with BGC-Argo data. As the dominant variability of phytoplankton in the northern SCS is at the seasonal timescale, we find that utilizing monthly-averaged BGC-Argo profiles provides an optimal fit between model outputs and measurements in the region, better than using high-frequency measurements.
first_indexed 2024-03-09T20:22:02Z
format Article
id doaj.art-16e4cc244f014bbca3fef706e8fd6d6a
institution Directory Open Access Journal
issn 2072-4292
language English
last_indexed 2024-03-09T20:22:02Z
publishDate 2022-03-01
publisher MDPI AG
record_format Article
series Remote Sensing
spelling doaj.art-16e4cc244f014bbca3fef706e8fd6d6a2023-11-23T23:44:35ZengMDPI AGRemote Sensing2072-42922022-03-01145129710.3390/rs14051297Biogeochemical Model Optimization by Using Satellite-Derived Phytoplankton Functional Type Data and BGC-Argo Observations in the Northern South China SeaChan Shu0Peng Xiu1Xiaogang Xing2Guoqiang Qiu3Wentao Ma4Robert J. W. Brewin5Stefano Ciavatta6State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, ChinaState Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, ChinaState Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, ChinaState Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, ChinaState Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, ChinaCentre for Geography and Environmental Science, College of Life and Environmental Sciences, Penryn Campus, University of Exeter, Penryn TR10 9EZ, UKPlymouth Marine Laboratory, Plymouth PL1 3DH, UKMarine biogeochemical models have been widely used to understand ecosystem dynamics and biogeochemical cycles. To resolve more processes, models typically increase in complexity, and require optimization of more parameters. Data assimilation is an essential tool for parameter optimization, which can reduce model uncertainty and improve model predictability. At present, model parameters are often adjusted using sporadic in-situ measurements or satellite-derived total chlorophyll-a concentration at sea surface. However, new ocean datasets and satellite products have become available, providing a unique opportunity to further constrain ecosystem models. Biogeochemical-Argo (BGC-Argo) floats are able to observe the ocean interior continuously and satellite phytoplankton functional type (PFT) data has the potential to optimize biogeochemical models with multiple phytoplankton species. In this study, we assess the value of assimilating BGC-Argo measurements and satellite-derived PFT data in a biogeochemical model in the northern South China Sea (SCS) by using a genetic algorithm. The assimilation of the satellite-derived PFT data was found to improve not only the modeled total chlorophyll-a concentration, but also the individual phytoplankton groups at surface. The improvement of simulated surface diatom provided a better representation of subsurface particulate organic carbon (POC). However, using satellite data alone did not improve vertical distributions of chlorophyll-a and POC. Instead, these distributions were improved by combining the satellite data with BGC-Argo data. As the dominant variability of phytoplankton in the northern SCS is at the seasonal timescale, we find that utilizing monthly-averaged BGC-Argo profiles provides an optimal fit between model outputs and measurements in the region, better than using high-frequency measurements.https://www.mdpi.com/2072-4292/14/5/1297biogeochemical modelparameter optimizationgenetic algorithmBGC-Argosatellite dataphytoplankton functional type
spellingShingle Chan Shu
Peng Xiu
Xiaogang Xing
Guoqiang Qiu
Wentao Ma
Robert J. W. Brewin
Stefano Ciavatta
Biogeochemical Model Optimization by Using Satellite-Derived Phytoplankton Functional Type Data and BGC-Argo Observations in the Northern South China Sea
Remote Sensing
biogeochemical model
parameter optimization
genetic algorithm
BGC-Argo
satellite data
phytoplankton functional type
title Biogeochemical Model Optimization by Using Satellite-Derived Phytoplankton Functional Type Data and BGC-Argo Observations in the Northern South China Sea
title_full Biogeochemical Model Optimization by Using Satellite-Derived Phytoplankton Functional Type Data and BGC-Argo Observations in the Northern South China Sea
title_fullStr Biogeochemical Model Optimization by Using Satellite-Derived Phytoplankton Functional Type Data and BGC-Argo Observations in the Northern South China Sea
title_full_unstemmed Biogeochemical Model Optimization by Using Satellite-Derived Phytoplankton Functional Type Data and BGC-Argo Observations in the Northern South China Sea
title_short Biogeochemical Model Optimization by Using Satellite-Derived Phytoplankton Functional Type Data and BGC-Argo Observations in the Northern South China Sea
title_sort biogeochemical model optimization by using satellite derived phytoplankton functional type data and bgc argo observations in the northern south china sea
topic biogeochemical model
parameter optimization
genetic algorithm
BGC-Argo
satellite data
phytoplankton functional type
url https://www.mdpi.com/2072-4292/14/5/1297
work_keys_str_mv AT chanshu biogeochemicalmodeloptimizationbyusingsatellitederivedphytoplanktonfunctionaltypedataandbgcargoobservationsinthenorthernsouthchinasea
AT pengxiu biogeochemicalmodeloptimizationbyusingsatellitederivedphytoplanktonfunctionaltypedataandbgcargoobservationsinthenorthernsouthchinasea
AT xiaogangxing biogeochemicalmodeloptimizationbyusingsatellitederivedphytoplanktonfunctionaltypedataandbgcargoobservationsinthenorthernsouthchinasea
AT guoqiangqiu biogeochemicalmodeloptimizationbyusingsatellitederivedphytoplanktonfunctionaltypedataandbgcargoobservationsinthenorthernsouthchinasea
AT wentaoma biogeochemicalmodeloptimizationbyusingsatellitederivedphytoplanktonfunctionaltypedataandbgcargoobservationsinthenorthernsouthchinasea
AT robertjwbrewin biogeochemicalmodeloptimizationbyusingsatellitederivedphytoplanktonfunctionaltypedataandbgcargoobservationsinthenorthernsouthchinasea
AT stefanociavatta biogeochemicalmodeloptimizationbyusingsatellitederivedphytoplanktonfunctionaltypedataandbgcargoobservationsinthenorthernsouthchinasea