477 / 2024-09-17 22:01:29

Trophic amplification in Southern Ocean plankton in a changing climate

plankton,Southern Ocean,climate change,model

Session 30 - Planktonic and Microbial Contributions to Marine Ecosystems and Biogeochemistry: Insights from Observations, Experiments, and Modeling

Marine plankton ecosystems form the base of the marine food web, a fundamental component of the global carbon cycle. Understanding how climate change affects plankton biomass is critical, particularly in the Southern Ocean, which plays a key role in global biogeochemical cycles. In this study, we employ a CMIP6 multi-model ensemble to investigate the impact of global warming on Southern Ocean plankton. Our analysis reveals various regional trends throughout the century, although overall plankton biomass remains relatively stable. Specifically, we identify three distinct trends: (1) in the Subtropical Zone, zooplankton biomass declines more than phytoplankton biomass, indicating negative trophic amplification; (2) in the Subpolar Zone (SPZ), both phytoplankton and zooplankton biomass remain relatively stable; and (3) in the Seasonal Ice Zone (SIZ), zooplankton biomass increases more than phytoplankton biomass, demonstrating positive trophic amplification. These findings highlight the importance of accounting for regional variations in plankton dynamics to fully understand the nuanced impacts of climate change.