Simulated decadal variations of surface and subsurface phytoplankton in the upstream Kuroshio Extension region

Progress in Earth and Planetary Science

Research Article

Masami Nonaka¹  Hideharu Sasaki¹  Tomoki Tozuka²  Yoshikazu Sasai³  Sayaka Yasunaka⁴ 

[1] Application Laboratory (APL), Research Institute for Value‐Added‐Information Generation (VAiG), Japan Agency for Marine‐Earth Science and Technology (JAMSTEC), Yokohama, Japan;Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan;Application Laboratory (APL), Research Institute for Value‐Added‐Information Generation (VAiG), Japan Agency for Marine‐Earth Science and Technology (JAMSTEC), Yokohama, Japan;Earth Surface System Research Center, Research Institute for Global Change, JAMSTEC, Yokosuka, Japan;Graduate School of Science, Tohoku University, Sendai, Japan;

关键词: Phytoplankton;    Kuroshio Extension;    Decadal variation;    Ecosystem model;    Eddy-resolving ocean general circulation model;   

DOI  :  10.1186/s40645-022-00532-0

 received in 2022-06-29, accepted in 2022-12-05,  发布年份 2022

来源: Springer

【 摘 要 】

Using outputs from an ecosystem model embedded in an eddy-resolving ocean general circulation model that can realistically simulate decadal modulations of the Kuroshio Extension (KE) between stable and unstable states, decadal variations of phytoplankton concentration in the upstream KE region are investigated. During stable states of the KE, surface phytoplankton concentrations are anomalously suppressed to the south of the KE front, while those to the north are anomalously enhanced. Although the surface phytoplankton concentration anomalies are prominent only during winter to spring, significant subsurface anomalies centered around 60 m depth persist even in summer and autumn. Anomalies persist throughout the year in phytoplankton biomass integrated over the upper 100 m despite the strong surface anomalies during the spring bloom season. An analysis of nitrogen concentration anomalies suggests that the vertical movement of the isopycnal surfaces, vertical mixing of nutrients, and meridional shifts in the KE jet contribute to the anomalous phytoplankton biomass.

【 授权许可】

CC BY   
© The Author(s) 2022

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