Articles | Volume 20, issue 20
https://doi.org/10.5194/bg-20-4323-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-20-4323-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Contribution of the open ocean to the nutrient and phytoplankton inventory in a semi-enclosed coastal sea
Qian Leng
Graduate School of Science and Engineering, Ehime University, 2-5 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
Center for Marine Environmental Studies, Ehime University, 2-5 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
Junying Zhu
State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 570228, China
Akihiko Morimoto
Center for Marine Environmental Studies, Ehime University, 2-5 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
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A bottom cold water mass (BCWM) is a widespread physical oceanographic phenomenon among coastal seas. Observations reveal a prominent interannual variation in a BCWM in the Seto Inland Sea during 1994–2015. We found that air–sea heat flux change during the warming season plays an important role in its interannual variation. Comparison with other BCWMs indicates that the size is a key factor for their difference. The findings help understand the response of BCWMs to sea surface forcing change.
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Short summary
Using a numerical model, we revealed that a large proportion of nutrients in a semi-enclosed sea (Seto Inland Sea, Japan) comes from the Pacific Ocean and supports about half of the phytoplankton growth in the sea. Such results imply that the human-made management of nutrient load from land needs to consider the presence of oceanic nutrients, which act as a background concentration and are not controlled by human activities.
Using a numerical model, we revealed that a large proportion of nutrients in a semi-enclosed sea...
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