The Southern Ocean plays a critical role in the global carbon cycle, yet there remians uncertainty regarding air-sea fluxes of carbon dioxide in the region. This project will initiate a novel airborne measurement program to address this: the Southern Ocean Carbon Gas Observatory (SCARGO). This approach will map distributions of carbon dioxide throughout the polar troposphere enabling robust estimates of summertime air-sea fluxes. SCARGO will leverage an observational platform of opportunity, the New York Air National Guard (ANG) LC-130 aircraft, operating austral summer from McMurdo Station supporting the United States Antarctic Program. Measurements will be made over three field seasons. Analysis and modeling activities will quantify Southern Ocean air-sea carbon dioxide air-exchange based on the observations, including the intra-seasonal evolution and interannual variability of current and future carbon climate fluxes.
SCARGO will address two fundamental research questions: (1) What is the magnitude and seasonal evolution of summertime Southern Ocean carbon dioxide uptake? and (2) How large is interannual variability in summertime carbon dioxide flux and what processes drive this variability? Aircraft measurements have several distinct advantages over other approaches to address these research questions. Additionally SCARGO also address several ancillary research questions leveraging concurrent measurements of atmospheric methane(CH4), carbon monoxide (CO), and water vapor (H2O). SCARGO PI's will involve students in the project, providing education and mentoring on the scientific and technical aspects of aircraft-based oceanography and numerical modeling. A postdoctoral scholar on the project will be trained in ocean biogeochemistry, Earth system and transport modeling. All analysis codes will be publicly released on GitHub in clear, well-documented forms enabling reproducibility. Finally, SCARGO will demonstrate the effectiveness of the NYANG LC-130 for atmospheric surveys, thereby contributing to realizing recommendations to establish an airborne research platform for the Antarctic.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.