Seasonal asymmetry in the evolution of surface ocean pCO2 and pH thermodynamic drivers and the influence on sea‐air CO2 flux
Rodgers, Keith B.
Palevsky, Hilary I.
Sabine, Christopher L.
MetadataShow full item record
It has become clear that anthropogenic carbon invasion into the surface ocean drives changes in the seasonal cycles of carbon dioxide partial pressure (pCO2) and pH. However, it is not yet known whether the resulting sea‐air CO2 fluxes are symmetric in their seasonal expression. Here we consider a novel application of observational constraints and modeling inferences to test the hypothesis that changes in the ocean's Revelle factor facilitate a seasonally asymmetric response in pCO2 and the sea‐air CO2 flux. We use an analytical framework that builds on observed sea surface pCO2 variability for the modern era and incorporates transient dissolved inorganic carbon concentrations from an Earth system model. Our findings reveal asymmetric amplification of pCO2 and pH seasonal cycles by a factor of two (or more) above preindustrial levels under Representative Concentration Pathway 8.5. These changes are significantly larger than observed modes of interannual variability and are relevant to climate feedbacks associated with Revelle factor perturbations. Notably, this response occurs in the absence of changes to the seasonal cycle amplitudes of dissolved inorganic carbon, total alkalinity, salinity, and temperature, indicating that significant alteration of surface pCO2 can occur without modifying the physical or biological ocean state. This result challenges the historical paradigm that if the same amount of carbon and nutrients is entrained and subsequently exported, there is no impact on anthropogenic carbon uptake. Anticipation of seasonal asymmetries in the sea surface pCO2 and CO2 flux response to ocean carbon uptake over the 21st century may have important implications for carbon cycle feedbacks.
© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Global Biogeochemical Cycles 32 (2018): 1476-1497, doi:10.1029/2017GB005855.
Suggested CitationArticle: Fassbender, Andrea, Rodgers, Keith B., Palevsky, Hilary I., Sabine, Christopher L., "Seasonal asymmetry in the evolution of surface ocean pCO2 and pH thermodynamic drivers and the influence on sea‐air CO2 flux", Global Biogeochemical Cycles 32 (2018): 1476-1497, DOI:10.1029/2017GB005855, https://hdl.handle.net/1912/10747
The following license files are associated with this item:
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-NoDerivatives 4.0 International
Showing items related by title, author, creator and subject.
Air-sea CO2 fluxes and the controls on ocean surface pCO2 seasonal variability in the coastal and open-ocean southwestern Atlantic Ocean : a modeling study Arruda, R.; Calil, P. H. R.; Bianchi, A. A.; Doney, Scott C.; Gruber, Nicolas; Lima, Ivan D.; Turi, G. (Copernicus Publications on behalf of the European Geosciences Union, 2015-10-12)We use an eddy-resolving, regional ocean biogeochemical model to investigate the main variables and processes responsible for the climatological spatio-temporal variability of pCO2 and the air-sea CO2 fluxes in the ...
Relationships between oceanic epizooplankton distributions and the seasonal deep chlorophyll maximum in the northwestern Atlantic Ocean Ortner, Peter B.; Wiebe, Peter; Cox, James L. (Woods Hole Oceanographic Institution, 1981-04)The potential significance of the Deep Chlorophyll Maximum (DCM) as a food resource for pelagic food chains was studied in three hydrographic regimes of the Northwestern Atlantic Ocean: the Slope Water, the Northern ...
Evaluating Southern Ocean biological production in two ocean biogeochemical models on daily to seasonal timescales using satellite chlorophyll and O2 / Ar observations Jonsson, Bror F.; Doney, Scott C.; Dunne, John P.; Bender, Michael L. (Copernicus Publications on behalf of the European Geosciences Union, 2015-02-04)We assess the ability of ocean biogeochemical models to represent seasonal structures in biomass and net community production (NCP) in the Southern Ocean. Two models are compared to observations on daily to seasonal ...