Insights into the year-round vertical distribution of chlorophyll concentration in high-latitude Arctic Ocean: implications for primary production

Journal Article · Tue Sep 02 00:00:00 EDT 2025 · Environmental Research Letters

DOI:https://doi.org/10.1088/1748-9326/adfb90· OSTI ID:3014015

Park, Jisoo ^[1]; Ko, Eunho ^[1]; Cho, Kyoung-Ho ^[1]; Jung, Jinyoung ^[1]; Lee, Youngju ^[1]; Yoo, Jaeill ^[1]; Moon, Jong Kuk ^[1]; Shim, Chorom ^[1]; Lee, Younjoo J ^[2]; Osinski, Robert ^[3]; Yang, Eun Jin ^[1]

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1. Korea Polar Research Institute, Incheon (Korea, Republic of)
2. Naval Postgraduate School, Monterey, CA (United States)
3. Polish Academy of Sciences, Sopot (Poland)

Climate-induced rapid changes in the Arctic Ocean, such as decreasing sea ice extent and increasing water temperature, are altering nutrient and light availability, profoundly impacting primary producer growth. However, access to the high-latitude Arctic Ocean is limited, and satellite data are primarily available only during summer, making continuous in-situ data collection challenging. We collected year-round chlorophyll-a (Chl-a) concentration data in high-latitude regions using a mooring system and performed a comparative analysis with reanalysis data. Unlike previous satellite-based studies, which typically rely on surface measurements, we used the annual vertical distribution of Chl-a. These data were applied to the vertically generalized production model to accurately estimate annual primary production. The moored Chl-a concentration data showed that phytoplankton exhibited a typical subsurface chlorophyll maximum (SCM) layer as sea ice retreated in June. Contrary to the gradually deepening SCM distribution predicted by model-based reanalysis data, the SCM layer persisted for approximately 4 months. This indicates that light and nutrient conditions within the SCM layer remained stable, sustaining continuous phytoplankton growth. Annual primary production, reflecting this vertical distribution of Chl-a concentration, was 6.85 gC m⁻² yr⁻¹. This exceeded satellite-based estimates by at least two-fold, highlighting the significant underestimation of primary production by satellite approaches. Estimating primary production while accounting for the vertical distribution of phytoplankton and light is essential for improving ecological models to better understand carbon cycle and food web changes in the Arctic Ocean, with important implications for climate change predictions.

• Research Organization: Naval Postgraduate School, Monterey, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Biological and Environmental Research (BER)
• Grant/Contract Number: 89243019SSC000030
• OSTI ID: 3014015
• Journal Information: Environmental Research Letters, Journal Name: Environmental Research Letters Journal Issue: 10 Vol. 20; ISSN 1748-9326
• Publisher: IOP Publishing
• Country of Publication: United States
• Language: English

Related Subjects

Arctic Ocean
Korean Arctic Mooring System
primary production
subsurface chlorophyll maximum (SCM)