USAP-DC

The Southern Ocean accounts for ~40% of the total ocean uptake of anthropogenic CO2 despite covering only 20% of the global ocean surface, and is particularly rich in long-lived eddies. These eddies, or large ocean whirlpools which can be observed from space, can alter air-sea fluxes of CO2 in ways that are not yet fully understood. New observations from autonomous platforms measuring ocean carbon content suggest that there is significant heterogeneity in ocean carbon fluxes which can be linked to these dynamic eddy features. Due to computational and time limitations, ocean eddies are not explicitly represented in most climate models, limiting our ability to understand the role eddies play in the ocean carbon cycle. This work will explore the impact of eddies on ocean carbon content and air-sea CO2 fluxes in the Southern Ocean using both model- and observation-based strategies and the findings will improve our understanding of the ocean’s role in the carbon cycle and in global climate. While this work will primarily be focused on the Southern Ocean, the results will be globally applicable. The researchers will also broaden interest in physical and chemical oceanography among middle school-age girls in the University of South Florida’s Oceanography Camp for Girls by augmenting existing lessons with computational methods in oceanography. This project aims to quantify the impacts of mesoscale eddy processes on ocean carbon content and air-sea carbon dioxide (CO2) fluxes in the Southern Ocean. For the modeling component, the investigators will explore relationships between eddies, ocean carbon content, and air-sea CO2 fluxes within the 1/6-degree resolution Biogeochemical Southern Ocean State Estimate (B-SOSE). They investigators will produce high-resolution composites of the carbon content and physical structure within both cyclonic and anticyclonic eddies by region, quantify the influence of these eddies on the overall simulated air-sea CO2 flux, and diagnose the physical mechanisms driving this influence. For the observational component, the investigators will match eddies observed via satellite altimetry to ocean carbon observations and characterize observed relationships between eddies and ocean carbon content with a focus on Southern Ocean winter observations where light limits biological processes, allowing isolation of the contribution of physical processes. This work will also provide motivation for higher resolution and better eddy parameterizations in climate models, more mesoscale biogeochemical observations, and integration of satellite SSH data into efforts to map air-sea fluxes of CO2. Each summer, the PI delivers a lab lesson at the University of South Florida Oceanography Camp for Girls (OCG), recognized by NSF as a “Model STEM Program for Women and Girls” focused on broadening participation by placing emphasis on recruiting a diverse group of young women. As part of this project, the existing interactive Jupyter Notebook-based Python coding Lab lesson will be augmented with a B-SOSE-themed modeling component, which will broaden interest in physical and chemical oceanography and data science, and expose campers to computational methods in oceanography.

Person	Role
Williams, Nancy	Investigator and contact
Chambers, Don	Co-Investigator
Tamsitt, Veronica	Co-Investigator

Antarctic Ocean and Atmospheric Sciences

Award # 2149500

USAP-2149500_1

Williams_BSOSEEddiesRevised_Data_Management_Plan.pdf

1. Tamsitt, V. (2023). New insights into air-sea fluxes and their role in Subantarctic Mode Water formation. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 381(2249). (doi:10.1098/rsta.2022.0066)