The OceanFlux Greenhouse Gases methodology for deriving a sea surface climatology of CO2 fugacity in support of air-sea gas flux studies

L. M. Goddijn-Murphy*, D. K. Woolf, P. E. Land, J. D. Shutler, C. Donlon

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    34 Citations (Scopus)
    69 Downloads (Pure)


    Climatologies, or long-term averages, of essential climate variables are useful for evaluating models and providing a baseline for studying anomalies. The Surface Ocean CO<inf>2</inf> Atlas (SOCAT) has made millions of global underway sea surface measurements of CO<inf>2</inf> publicly available, all in a uniform format and presented as fugacity, f<inf>CO2</inf>. As f<inf>CO2</inf> is highly sensitive to temperature, the measurements are only valid for the instantaneous sea surface temperature (SST) that is measured concurrently with the in-water CO<inf>2</inf> measurement. To create a climatology of f<inf>CO2</inf> data suitable for calculating air-sea CO<inf>2</inf> fluxes, it is therefore desirable to calculate f<inf>CO2</inf> valid for a more consistent and averaged SST. This paper presents the OceanFlux Greenhouse Gases methodology for creating such a climatology. We recomputed SOCAT's f<inf>CO2</inf> values for their respective measurement month and year using monthly composite SST data on a 1° × 1° grid from satellite Earth observation and then extrapolated the resulting f<inf>CO2</inf> values to reference year 2010. The data were then spatially interpolated onto a 1° × 1° grid of the global oceans to produce 12 monthly f<inf>CO2</inf> distributions for 2010, including the prediction errors of f<inf>CO2</inf> produced by the spatial interpolation technique. The partial pressure of CO<inf>2</inf> (p<inf>CO2</inf>) is also provided for those who prefer to use p<inf>CO2</inf>. The CO<inf>2</inf> concentration difference between ocean and atmosphere is the thermodynamic driving force of the air-sea CO<inf>2</inf> flux, and hence the presented f<inf>CO2</inf> distributions can be used in air-sea gas flux calculations together with climatologies of other climate variables.

    Original languageEnglish
    Pages (from-to)519-541
    Number of pages23
    JournalOcean Science
    Issue number4
    Publication statusPublished - 8 Jul 2015

    ASJC Scopus subject areas

    • Oceanography
    • Palaeontology


    Dive into the research topics of 'The OceanFlux Greenhouse Gases methodology for deriving a sea surface climatology of CO2 fugacity in support of air-sea gas flux studies'. Together they form a unique fingerprint.

    Cite this