SeaFlux: Harmonized Global Sea-Air CO2 Fluxes

SeaFlux provides harmonized global estimates of sea-air carbon dioxide (CO2) fluxes calculated using a standardized bulk formula. The dataset includes the individual components of the flux equation—sea surface pCO2, atmospheric pCO2, gas transfer velocity, solubility, and ice fraction—derived from multiple observational products and reanalyses. This structure allows for consistent intercomparison and error analysis across different methodological choices for key parameters.

Use Cases

• Intercomparing ocean carbon sink estimates based on six different surface pCO2 mapping products.
• Assessing uncertainty in global CO2 fluxes stemming from five different wind speed products used to calculate gas transfer velocity.
• Analyzing the spatial and temporal variability of the oceanic CO2 sink using a standardized, reproducible calculation framework.
• Validating Earth system model outputs of air-sea CO2 exchange against a multi-product observational synthesis.

Strengths

• Provides a multi-ensemble dataset combining six surface pCO2 products and five wind products, enabling systematic uncertainty quantification.
• Includes all intermediate variables (e.g., K0, Kw, pCO2 sea/atm, ice fraction) used in the flux calculation, promoting transparency and reducing methodological errors.
• Uses a standardized calculation approach (Weiss 1974, Wanninkhof 1992) applied consistently across all input data sources.

Limitations

• Key metadata such as temporal coverage, spatial resolution, row count, and file size are not provided in the available source descriptions.
• The dataset's update frequency and the specific version of input products (e.g., ERA5, OISST) are unknown, which may affect reproducibility over time.
• Relies on a filler climatology (Landschützer et al., 2020) for missing regions in some pCO2 products, which may introduce smoothing or bias in data-sparse areas.

Provenance

Source

Compiled by Luke Gregor (ETH Zurich) from multiple public sources including SOCOM pCO2 products, NOAA marine boundary layer data, EN4 salinity, OISST, and wind reanalyses (CCMPv2, ERA5, JRA55, NCEP1, NCEP2).

Collection Method

Fluxes calculated using the standardized bulk formula FCO2 = K0 * Kw * (pCO2_sea - pCO2_atm) * (1 - ice_fraction). Components are calculated from source data using cited parameterizations.

Geography

Global ocean coverage.