This dataset contains monthly interpolated sea surface fugacity of carbon dioxide (fCO2) from 1982 through 2015 is estimated from monthly atmospheric CO2, temperature, and salinity. Firstly, the disequilibrium between the observed seawater fCO2 and fCO2air (i.e., ΔfCO2; ΔfCO2 = fCO2 – fCO2air) is estimated using a bayesian-neural-network approach for each 1°×1° grid box in the MAB and the SAB. The input parameters are latitude, longitude, SST, and SSS. The output parameter is ΔfCO2. The feedforward backpropagation network is constructed by two hidden layers with tanh activation functions. The neural network is trained with the Levenberg-Marquardt algorithm (Hagan and Menhaj, 1994). Then fCO2 is calculated using ΔfCO2 and fCO2air. Next, continuous monthly SST and SSS data from 1982 to 2015 are used to calculate output with the trained network to fill in SOCAT data gaps. Monthly pH, DIC, and Ωarag are calculated from fCO2 and salinity-derived TA using CO2SYS (Van Heuven et al., 2009) with the first and second dissociation constants of carbonic acid in seawater (K1 and K2) from Lueker et al. (2000) and borate-to-salinity ratio determined by Uppström (1974). TA is derived from salinity using their linear relationships in the MAB and the SAB (Cai et al., 2010).

This dataset consists of the co-located surface discrete fCO2 at 20 ˚C and underway fCO2 measurements at sea surface temperature (SST) for 21 cruises spanning the Pacific, Atlantic, Indian Oceans and Gulf of Mexico from 1991-07-12 to 2020-04-15. In addition, calculated fCO2 from alkalinity (TA) and total dissolved inorganic carbon (DIC) are provided. The co-located discrete fCO2 at 20 ˚C and underway fCO2 measurements at SST are used to infer the temperature dependence of CO2. For the 21 cruises spanning the major ocean basins from 1992-2020 a temperature dependence of 4.13 ± 0.01 % ˚C-1 is determined in close agreement with a widely used previous empirical estimate of 4.23 ± 0.02 % ˚C-1 for North Atlantic surface water. No statistically significant dependence on temperature or inorganic carbon speciation of the surface water was discerned as dependency on these factors is weak and it was masked by a range of overlapping temperatures and chemical compositions. The temperature dependency of calculated fCO2 yield a dependency of 4.10 % ˚C-1 for 17 cruises where there are co-located measurements of fCO2, alkalinity (TA) and dissolved inorganic carbon (DIC).

The ocean is a sink for ~25% of the atmospheric CO2 emitted by human activities, an amount in excess of 2 petagrams of carbon per year (PgC yr−1). Time-resolved estimates of global ocean-atmosphere CO2 flux provide an important constraint on the global carbon budget. However, previous estimates of this flux, derived from surface ocean CO2 concentrations, have not corrected the data for temperature gradients between the surface and sampling at a few meters depth, or for the effect of the cool ocean surface skin. Here we calculate a time history of ocean-atmosphere CO2 fluxes from 1992 to 2018, corrected for these effects. These increase the calculated net flux into the oceans significantly.

This dataset contains a combined globally mapped estimate of the air-sea exchange of carbon dioxide (CO2) based on Surface Ocean CO2 Atlas Database (SOCAT) partial pressure of CO2 (pCO2) and calculated pCO2 from Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) biogeochemistry floats from 1982 to 2017. The pCO2 fields were created using a 2-step neural network technique. In a first step, the global ocean is divided into 16 biogeochemical provinces using a self-organizing map. In a second step, the non-linear relationship between variables known to drive the surface ocean carbon system and gridded observations from the SOCAT dataset (Bakker et al., 2016) starting in 1982 in various combinations with calculated pCO2 from biogeochemical ARGO floats starting in 2014 from the SOCCOM project (Johnson et al., 2017) is reconstructed using a feed-forward neural network within each province separately. The final product is then produced by projecting these driving variables, i.e., surface temperature, chlorophyll, mixed layer depth, and atmospheric CO2 onto oceanic pCO2 using these non-linear relationships. This results in monthly pCO2 fields at 1°x1° resolution covering the entire globe with the exception of the Arctic Ocean and few marginal seas. The air-sea CO2 flux is then computed using a standard bulk formula.

This dataset includes continuous sea surface measurements of pCO2, temperature, salinity and atmospheric pressure data during the R/V Marion-Dufresne cruise Clim-EPARSES (EXPOCODE 35MV20190405) in the Indian Ocean and Mozambique Channel from 2019-04-04 to 2019-04-30. The project Clim-EPARSES (PI, Aline Tribollet/LOCEAN-IPSL-IRD) aims at evaluating the impact of global change (warming, acidification) over the last decades on the coral reef ecosystems in the Eparses Islands (Scattered Islands). The project conducted in April 2019 onboard the R.V. Marion-Dufresne (TAAF) included underway sea surface observations of the ocean carbonate properties in the Mozambique Channel, around Eparses Islands and in the Indian Ocean.

The late Taro Takahashi (LDEO/Columbia University) provided the first near-global monthly air-sea CO2 flux climatology in Takahashi et al. (1997), based on available surface water partial pressure of CO2 measurements. This product has been a benchmark for uptake of CO2 in the ocean. Several versions have been provided since, with improvements in procedures and large increases in observations, culminating in the authoritative assessment in Takahashi et al. (2009). Here we provide and document the last iteration using a greatly increased dataset (SOCATv2022) and determining fluxes using air-sea partial pressure differences as a climatological reference for the period 1980-2021. The resulting net flux for the open ocean region is estimated as -1.79 PgC yr-1 which compares well with other global mean flux estimates. While global flux results are consistent, differences in regional means and seasonal amplitudes are discussed. Consistent with other studies, we find the largest differences in the data-sparse southeast Pacific and Southern Ocean.

This dataset includes CO2 Measurements in the Atmosphere and Surface Ocean Waters from Scripps Institution of Oceanography R/Vs Downwind, Monsoon, and Lusiad Expeditions, collected from HORIZON, SPENCER F. BAIRD, and ARGO in the Andaman Sea or Burma Sea, Arabian Sea, Bay of Bengal, Caribbean Sea, Indian Ocean, Laccadive Sea, Malacca Straits, Mozambique Channel, North Atlantic Ocean, North Pacific Ocean, Philippine Sea, Singapore Straits, South Atlantic Ocean, South China Sea (Nan Hai), South Pacific Ocean, Southern Oceans (> 60 degrees South) and Tasman Sea from 1957-10-21 to 1963-08-15. These data include AIR-SEA DIFFERENCE - PARTIAL PRESSURE (OR FUGACITY) OF CARBON DIOXIDE, BAROMETRIC PRESSURE, Partial pressure (or fugacity) of carbon dioxide - atmosphere, Partial pressure (or fugacity) of carbon dioxide - water and SEA SURFACE TEMPERATURE. The instruments used to collect these data include Carbon dioxide (CO2) gas analyzer and Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement. These data were collected by Charles D. Keeling of Scripps Institution of Oceanography (SIO) as part of the Keeling_1957_1963 dataset. CDIAC associated the following cruise ID(s) with this dataset: KEEL19571021

This dataset provides 1 km gridded monthly estimates of surface ocean partial pressure of CO2 (pCO2) and air-sea flux of CO2 (CO2 flux) for the northern Gulf of America for the period 2006 through 2010. Estimates of pCO2 were derived from MODIS/Aqua satellite imagery in combination with ship-based observations. Estimates of CO2 flux were derived from estimates of seawater pCO2, wind fields, and atmospheric pCO2.

This dataset includes biological, chemical, meteorological, physical and underway - surface data collected from NOAA Ship RONALD H. BROWN in the Caribbean Sea, Gulf of Mexico, North Atlantic Ocean and South Atlantic Ocean from 2009-04-17 to 2009-10-18 and retrieved during cruise RB-09-01, RB-09-02, RB-09-03, RB-09-04, RB-09-05 and RB-09-05T. These data include AIR TEMPERATURE, BAROMETRIC PRESSURE, CARBON DIOXIDE - AIR, CARBON DIOXIDE - PARTIAL PRESSURE - DIFFERENCE, FLUORESCENCE, Partial pressure (or fugacity) of carbon dioxide, SALINITY, SEA SURFACE TEMPERATURE, WIND DIRECTION and WIND SPEED. The instruments used to collect these data include Carbon dioxide (CO2) gas analyzer and Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement. These data were collected by Rik Wanninkhof of NOAA Atlantic Oceanographic and Meteorological Laboratory as part of NOAA Ship Ronald H. Brown 2009 Underway Data data set.