Japan Geoscience Union Meeting 2025

Presentation information

[E] Poster

A (Atmospheric and Hydrospheric Sciences ) » A-OS Ocean Sciences & Ocean Environment

[A-OS13] Exploring Variability and Changes in Ocean Biogeochemical Cycles

Wed. May 28, 2025 5:15 PM - 7:15 PM Poster Hall (Exhibition Hall 7&8, Makuhari Messe)

convener:Yohei Takano(British Antarctic Survey), Jerry Tjiputra(Norwegian Research Centre, Bjerknes Centre for Climate Research), Hidetaka Kobayashi(Faculty of Science, The University of Toyama), Ryohei Yamaguchi(Japan Agency for Marine-Earth Science and Technology)

5:15 PM - 7:15 PM

[AOS13-P10] Multi-Centennial Evolution of Ocean Biogeochemistry Under Extended SSP Simulations

*Hidetaka Kobayashi1, Tokuta Yokohata2, Keith Rodgers3,4 (1.University of Toyama, 2. National Institute for Environmental Studies, 3.WPI-Advanced Institute for Marine Ecosystem Change, 4.Tohoku University)

Keywords:Ocean biogeochemical cycles, Earth System Model, Projections on a Centennial to Multi-Centennial Scale

The extended response of marine biogeochemistry to greenhouse gas emissions remains a crucial area of climate research, particularly in the context of long-term projections beyond the 21st century. This study employs the MIROC-ES2L Earth System Model to investigate how ocean biogeochemical cycles evolve under different socio-economic pathways (SSPs) in simulations extending to the year 2500. By analyzing low, medium, and high emission pathways, as well as overshoot scenarios, we aim to assess the potential long-term impacts of prolonged warming on marine biogeochemical processes.
Our results indicate that biogeochemical tracers undergo significant redistribution over centuries, primarily driven by changes in deep ocean circulation. Additionally, biological production in the equatorial region exhibits varying responses depending on the emission scenario, with some scenarios showing an increase while others indicate a decline. Although changes in oxygen levels in equatorial waters remain relatively small, high-latitude regions experience a significant reduction in oxygen concentration, which could have important implications for marine ecosystems.
Looking ahead, a key research priority is to identify the drivers of carbon cycle changes and the differences in carbon uptake efficiency across the various emission scenarios. Further investigation is also needed to understand the distinct responses between polar regions, particularly the Arctic and Antarctic, and how they compare with other oceanic regions. Moreover, an important question is whether these results can be validated through comparisons with other models. Future research will also explore the role of seasonal variations and assess the potential impacts of prolonged biogeochemical changes on marine ecosystem stress.