Publication: Seasonal variability of net sea-air CO2 fluxes in a coastal region of the northern Antarctic Peninsula

A new paper, titled “Seasonal variability of net sea-air CO₂ fluxes in a coastal region of the northern Antarctic Peninsula”, has been published in Nature Scientific Reports and might be of interest to the Antarctic Community.

Abstract:

We show an annual overview of the sea-air CO₂ exchanges and primary drivers in the Gerlache Strait, a hotspot for climate change that is ecologically important in the northern Antarctic Peninsula. In autumn and winter, episodic upwelling events increase the remineralized carbon in the sea surface, leading the region to act as a moderate or strong CO₂ source to the atmosphere of up to 40 mmol m^–2 day^–1. During summer and late spring, photosynthesis decreases the CO₂ partial pressure in the surface seawater, enhancing ocean CO₂ uptake, which reaches values higher than − 40 mmol m^–2 day^–1. Thus, autumn/winter CO₂ outgassing is nearly balanced by an only 4-month period of intense ocean CO₂ ingassing during summer/spring. Hence, the estimated annual net sea-air CO₂ flux from 2002 to 2017 was 1.24 ± 4.33 mmol m^–2 day^–1, opposing the common CO₂ sink behaviour observed in other coastal regions around Antarctica. The main drivers of changes in the surface CO₂ system in this region were total dissolved inorganic carbon and total alkalinity, revealing dominant influences of both physical and biological processes. These findings demonstrate the importance of Antarctica coastal zones as summer carbon sinks and emphasize the need to better understand local/regional seasonal sensitivity to the net CO₂ flux effect on the Southern Ocean carbon cycle, especially considering the impacts caused by climate change.

Reference:

Monteiro, T., Kerr, R. & Machado, E.d. Seasonal variability of net sea-air CO₂ fluxes in a coastal region of the northern Antarctic Peninsula. Sci Rep 10, 14875 (2020). https://doi.org/10.1038/s41598-020-71814-0