Surface Ocean CO₂ Observations


The Surface Ocean CO₂ Atlas (SOCAT) is a synthesis activity for quality-controlled, surface ocean fCO₂ (fugacity of carbon dioxide) observations by the international marine carbon research community (>100 contributors). SOCAT data is publicly available, discoverable and citable. SOCAT enables quantification of the ocean carbon sink and ocean acidification and evaluation of ocean biogeochemical models. SOCAT, which celebrated its 10th anniversary in 2017, represents a milestone in biogeochemical and climate research and in informing policy.

Type and number of data sets

SOCAT data are released in versions. Each succeeding version contains new data sets as well as updates of older ones. The first version of SOCAT was released in 2011, the second and third version followed biennially. Automation allowed annual public releases since version 4. The latest SOCAT version (version 2021) has 30.6 million observations from 1957 to 2020 for the global oceans and coastal seas. Calibrated sensor data are also available.
SOCAT version 2021 was released on the 15th of June 2021, containing data submitted on or before 15th of January 2021. Data submissions for the next version are welcome at any time, and will be included in the next SOCAT release in 2022.

Core services

SOCAT is a core Global Ocean Observing System data product for biogeochemistry endorsed by the Global Ocean Observing System GOOS. This Surface Ocean CO₂ Atlas (SOCAT) data set serves a wide range of user communities. Two distinct data products are available:

  • a 2nd level quality controlled global surface ocean fCO₂ data set,
  • a gridded SOCAT product of monthly surface water fCO₂ means on a 1° x 1° grid with no temporal or spatial interpolation.

Function in Blue-Cloud

SOCAT is one of the nine blue data infrastructures, federated in the Blue-Cloud Data Discovery & Access Service.