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

Type Article
Date 2015-07-08
Language English
Author(s) Goddijn-Murphy L. M.1, Woolf D. K.2, Land P. E.3, Shutler J. D.4, Donlon C.5
Affiliation(s) 1 : Univ Highlands & Isl, ERI, Thurso, Caithness, England.
2 : Heriot Watt Univ, ICIT, Stromness, Orkney, England.
3 : Plymouth Marine Lab, Plymouth, Devon, England.
4 : Univ Exeter, Ctr Geog Environm & Soc, Penryn, Cornwall, England.
5 : European Space Agcy, Estec, NL-2200 AG Noordwijk, Netherlands.
Source Ocean Science (1812-0784) (Copernicus Gesellschaft Mbh), 2015-07-08 , Vol. 11 , N. 4 , P. 519-541
DOI 10.5194/os-11-519-2015
WOS© Times Cited 32
Note Special issue : Air-sea flux climatology; progress and future prospectsEditor(s): C. Robinson, J. Kaiser, C. McNeil, D. Woolf, J. Shutler, C. Garbe, and P. Challeno
Abstract Climatologies, or long-term averages, of essential climate variables are useful for evaluating models and providing a baseline for studying anomalies. The Surface Ocean CO2 Atlas (SOCAT) has made millions of global underway sea surface measurements of CO2 publicly available, all in a uniform format and presented as fugacity, f(CO2). As f(CO2) 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 CO2 measurement. To create a climatology of f(CO2) data suitable for calculating air-sea CO2 fluxes, it is therefore desirable to calculate f(CO2) 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(CO2) values for their respective measurement month and year using monthly composite SST data on a 1 degrees x 1 degrees grid from satellite Earth observation and then extrapolated the resulting f(CO2) values to reference year 2010. The data were then spatially interpolated onto a 1 degrees x 1 degrees grid of the global oceans to produce 12 monthly f(CO2) distributions for 2010, including the prediction errors of f(CO2) produced by the spatial interpolation technique. The partial pressure of CO2 (p(CO2)) is also provided for those who prefer to use p(CO2). The CO2 concentration difference between ocean and atmosphere is the thermodynamic driving force of the air-sea CO2 flux, and hence the presented f(CO2) distributions can be used in air-sea gas flux calculations together with climatologies of other climate variables.
Full Text
File Pages Size Access
Publisher's official version 23 8 MB Open access
Supplement 16 MB Open access
Preprint 54 11 MB Open access
Supplement to the preprint 16 MB Open access
Top of the page