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Article

Performance Evaluation of CMIP6 Models on Surface Chlorophyll and Ocean pCO2 in the Northwestern Pacific

CMIP6의 북서태평양 표층 엽록소 농도와 해양 이산화탄소 분압의 재현성 평가

Daehyuk Kim1
,
Na-Hyeon Lee2
,
Jae-Hong Moon123*
김 대혁1
,
이 나현2
,
문 재홍123*
1Center for Sea-Level Changes, Jeju National University, Jeju 63243, Korea
2Faculty of Earth and Marine Convergence, Earth and Marine Science Major, Jeju National University, Jeju, 63243, Korea
3Department of Earth and Marine Science, College of Ocean Sciences, Jeju National University, Jeju 63243, Korea
1제주대학교 해수면변동연구센터 (63243) 제주특별자치도 제주시 제주대학로 102
2제주대학교 지구해양융합학부 지구해양과학전공 (63243) 제주특별자치도 제주시 제주대학로 102
3제주대학교 해양과학대학 지구해양과학과 (63243) 제주특별자치도 제주시 제주대학로 102
*Corresponding Author
11 March 2026. pp. 1-18
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Abstract

As one of the major carbon sinks, the northwestern Pacific is a crucial area for understanding how ocean absorbs and stores atmospheric CO2, especially in the context of increasing anthropogenic CO2 emissions. Although the Earth System Model (ESM) has been widely used as a useful tool to study complex interplay of physical and biogeochemical processes, significant differences exist between ESMs in simulating reliable results on regional scales due to limited spatial resolution and different physical-biogeochemical parameterization schemes. In this study, we analyzed the seasonal variability of surface chlorophyll concentration and ocean pCO2 in the northwestern Pacific using the results of nine ESMs participating in CMIP6 and evaluated the simulation performance of the EMSs using statistical indices. Overall, the ESMs simulate surface chlorophyll increase in spring associated with phytoplankton blooms in the northwestern Pacific similarly to satellite observations, but fail to simulate an increase in autumn, especially at high latitudes above 30°N. Most of the models reproduce the summer decrease in pCO2 due to rising sea surface temperature, but there is a large difference in reproducibility among models in high-latitude regions where water temperatures remain low year-round. Models that simulate chlorophyll concentration well tend to reproduce the pCO2 reduction in subpolar region during spring, showing that biological processes play an important role in simulating pCO2 in high-latitude regions. According to Total Ranking (TR) result, top-performing models include EC-Earth3-CC and CMSS-ESM2 with respect to surface chlorophyll and pCO2, while series of CanECS5 and NorESM2 models show relatively lower TR.

Keywords
surface chlorophyll concentration
surface ocean pCO2
CMIP6
Northwestern Pacific
Performance evaluation
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Information
  • Publisher :Korea Institute of Ocean Science and Technology
  • Publisher(Ko) :한국해양과학기술원
  • Journal Title :Ocean and Polar Research
  • Journal Title(Ko) :Ocean and Polar Research
  • Volume : 48
  • Pages :1-18
  • Received Date : 2026-01-06
  • Revised Date : 2026-02-05
  • Accepted Date : 2026-02-06
  • Published Date : 2026-03-11
  • DOI :https://doi.org/10.4217/OPR.2026005
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