Detecting regional modes of variability in observation-based surface ocean pCO2
Landschützer, P.; Ilyina, T.; Lovenduski, N.S. (2019). Detecting regional modes of variability in observation-based surface ocean pCO2. Geophys. Res. Lett. 46(5): 2670-2679. https://dx.doi.org/10.1029/2018gl081756 In: Geophysical Research Letters. American Geophysical Union: Washington. ISSN 0094-8276; e-ISSN 1944-8007, more | |
Authors | | Top | - Landschützer, P., more
- Ilyina, T.
- Lovenduski, N.S.
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Abstract | We use a neural network-based estimate of the sea surface partial pressure of CO2 (pCO2) derived from measurements assembled within the Surface Ocean CO2 Atlas to investigate the dominant modes of pCO2 variability from 1982 through 2015. Our analysis shows that detrended and deseasonalized sea surface pCO2 varies substantially by region and the respective frequencies match those from the major modes of climate variability (Atlantic Multidecadal Oscillation, Pacific Decadal Oscillation, multivariate ENSO index, Southern Annular Mode), suggesting a climate modulated air-sea exchange of CO2. We find that most of the regional pCO2 variability is driven by changes in the ocean circulation and/or changes in biology, whereas the North Atlantic variability is tightly linked to temperature variations in the surface ocean and the resulting changes in solubility. Despite the 34-year time series, our analysis reveals that we can currently only detect one to two periods of slow frequency oscillations, challenging our ability to robustly link pCO2 variations to climate variability. |
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