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Title: Predicting near-term variability in ocean carbon uptake
Abstract. Interannual variations in air–sea fluxes of carbon dioxide (CO2) impactthe global carbon cycle and climate system, and previous studies suggest thatthese variations may be predictable in the near term (from a year to a decadein advance). Here, we quantify and understand the sources of near-termpredictability and predictive skill in air–sea CO2 flux on global andregional scales by analyzing output from a novel set of retrospective decadalforecasts of an Earth system model. These forecasts exhibit the potential topredict year-to-year variations in the globally integrated air–sea CO2flux several years in advance, as indicated by the high correlation of theforecasts with a model reconstruction of past CO2 flux evolution. Thispotential predictability exceeds that obtained solely from foreknowledge ofvariations in external forcing or a simple persistence forecast, with thelongest-lasting forecast enhancement in the subantarctic Southern Ocean andthe northern North Atlantic. Potential predictability in CO2 fluxvariations is largely driven by predictability in the surface ocean partialpressure of CO2, which itself is a function of predictability in surfaceocean dissolved inorganic carbon and alkalinity. The potentialpredictability, however, is not realized as predictive skill, as indicated bythe moderate to low correlation of the forecasts with anobservationally based CO2 flux product. Nevertheless, our results suggestthat year-to-year variations in ocean carbon uptake have the potential to bepredicted well in advance and establish a precedent for forecasting air–seaCO2 flux in the near future.  more » « less
Award ID(s):
1752724
PAR ID:
10087491
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Earth System Dynamics
Volume:
10
Issue:
1
ISSN:
2190-4987
Page Range / eLocation ID:
45 to 57
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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