TY - JOUR
T1 - Sea ice controls net ocean uptake of carbon dioxide by regulating wintertime stratification
AU - Droste, Elise S.
AU - Bakker, Dorothee C. E.
AU - Venables, Hugh J.
AU - Jones, Elizabeth M.
AU - Meredith, Michael P.
AU - Dall’Olmo, Giorgio
AU - Hoppema, Mario
AU - Legge, Oliver J.
AU - Lee, Gareth A.
AU - Queste, Bastien Y.
N1 - Data availability:
Access details for Rothera Time Series data, including CTD measurements, nutrient concentrations and sea ice observations, can be found in Venables et al. Bathymetry data are available on Pangaea. Wind speed and atmospheric pressure data are made available by the British Antarctic Survey. Atmospheric CO2 mixing ratios measured in air samples collected at Palmer Research Station on Anvers Island are published on the NOAA Global Monitoring Laboratory Data Repository. Rothera Time Series DIC and TA data between 2010 and 2014 have previously been published on NOAA National Centers for Environmental Information. The full Rothera DIC/TA dataset until 2020, including data between 2010 and 2014, is publicly available on the UK Polar Data Centre.
Code availability:
Python package Calkulate was used to determine seawater total alkalinity, and PyCO2SYS was used to determine seawater fCO2.
Funding information: The Rothera Time Series has been funded by NERC through a sequence of National Capability awards, most recently NE/Y006178/1 (PRESCIENT). E.S.D. was supported by the Natural Environment Research Council (NERC) through the EnvEast Doctoral Training Partnership (grant no. NE/L002582/1), and partly by funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 821001 and the NERC PICCOLO award (NE/PO21395/1). D.C.E.B. was partly supported by the NERC PICCOLO award (NE/PO21395/1). E.M.J. was supported by the research programme 866.13.006 (partly) financed by the Netherlands Polar Programme at the Dutch Research Council (Nederlandse Organisatie voor Wetenschappelijk Onderzoek). E.M.J. gratefully acknowledges the Royal NIOZ and University of Groningen for the opportunity to conduct fieldwork at the Dirck Gerritsz and Bonner laboratories at Rothera from 2013 to 2017. DIC/TA samples collected between the end of 2013 and 2016 were analysed onsite at Rothera, and samples from 2016 until January 2017 were analysed at UEA. The participation of M.P.M. was partly funded by the award NE/W004933/1 (BIOPOLE). We acknowledge support by the Open Access publication fund of Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung.
PY - 2025/6/18
Y1 - 2025/6/18
N2 - Sea-air exchange of carbon dioxide in the Southern Ocean is strongly seasonal, with ocean uptake in summer, which is partly offset by carbon dioxide outgassing in winter. This seasonal balance can shift due to sea ice conditions, inducing interannual variability in the Southern Ocean carbon sink. A decade (2010–2020) of unique, year-round marine carbonate chemistry observations from the Rothera Time Series (West Antarctic Peninsula) reveals that interannual variability in seawater fugacity of carbon dioxide depends on wintertime processes. Sea ice duration controls ocean stratification, which acts as a gateway to the carbon-rich ocean interior. Consequently, years with persistent sea ice cover and high mean winter stratification absorb, on average, 20% more carbon dioxide than years with less sea ice and weaker stratification in winter. Wintertime marine observations are therefore essential to resolve critical processes and reliably quantify interannual variability of the sea-air carbon dioxide flux in seasonally sea ice-covered regions.
AB - Sea-air exchange of carbon dioxide in the Southern Ocean is strongly seasonal, with ocean uptake in summer, which is partly offset by carbon dioxide outgassing in winter. This seasonal balance can shift due to sea ice conditions, inducing interannual variability in the Southern Ocean carbon sink. A decade (2010–2020) of unique, year-round marine carbonate chemistry observations from the Rothera Time Series (West Antarctic Peninsula) reveals that interannual variability in seawater fugacity of carbon dioxide depends on wintertime processes. Sea ice duration controls ocean stratification, which acts as a gateway to the carbon-rich ocean interior. Consequently, years with persistent sea ice cover and high mean winter stratification absorb, on average, 20% more carbon dioxide than years with less sea ice and weaker stratification in winter. Wintertime marine observations are therefore essential to resolve critical processes and reliably quantify interannual variability of the sea-air carbon dioxide flux in seasonally sea ice-covered regions.
UR - https://www.scopus.com/pages/publications/105008737832
U2 - 10.1038/s43247-025-02395-x
DO - 10.1038/s43247-025-02395-x
M3 - Article
VL - 6
SP - 1
EP - 11
JO - Communications Earth & Environment
JF - Communications Earth & Environment
IS - 1
M1 - 457
ER -
SDG 14 Life Below Water