|Prevalence of strong vertical CO2 and O2 variability in the top meters of the ocean|Calleja, M.L.; Duarte, C.M.; Álvarez, M.; Vaquer-Sunyer, R.; Agustí, S.; Herndl, G.J. (2013). Prevalence of strong vertical CO2 and O2 variability in the top meters of the ocean. Global Biogeochem. Cycles 27: 941–949. hdl.handle.net/10.1002/gbc.20081
In: Global Biogeochemical Cycles. American Geophysical Union: Washington, DC. ISSN 0886-6236, more
pCO2 variability; top meters; temperature; oxygen concentration; oceans
|Authors|| || Top |
- Calleja, M.L.
- Duarte, C.M., more
- Álvarez, M.
- Vaquer-Sunyer, R.
- Agustí, S.
- Herndl, G.J., more
The gradient in the partial pressure of carbon dioxide (pCO2) across the air-sea boundary layer is the main driving force for the air-sea CO2 flux. Global data bases for surface seawater pCO2 are actually based on pCO2 measurements from several meters below the sea surface, assuming a homogeneous distribution between the diffusive boundary layer and the upper top meters of the ocean. Compiling vertical profiles of pCO2, temperature, and dissolved oxygen in the upper 5–8 m of the ocean from different biogeographical areas, we detected a mean difference between the boundary layer and 5 m pCO2 of 13?±?1 µatm. Temperature gradients accounted for only 11% of this pCO2 gradient in the top meters of the ocean; thus, pointing to a heterogeneous biological activity underneath the air-sea boundary layer as the main factor controlling the top meters pCO2 variability. Observations of pCO2 just beneath the air-sea boundary layer should be further investigated in order to estimate possible biases in calculating global air-sea CO2 fluxes.