SOCAT - Surface Ocean CO₂ Atlas

Endorsed by SOLAS since April 2007


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). The 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.

Find more about SOCAT at:

Annual Update

The ocean absorbs a quarter of the global CO₂ emissions from human activity. It is unclear how ocean CO₂ uptake will evolve, as humankind moves towards net zero CO₂ emissions. SOCAT has an annual public release of in situ quality-controlled fCO₂ measurements, typically in mid-June. The SOCAT community-led synthesis product is a key step in the value chain based on in situ CO₂ measurements of the oceans, which provides policy makers with essential information on ocean CO₂ uptake in climate negotiations. The global need for accurate knowledge of ocean CO₂ uptake and its variation (including ocean acidification) highlights the need for sustained funding of in situ surface ocean CO₂ observations and their synthesis. In 2021, a total of 74 peer-reviewed papers, reports and book chapters are published based on SOCAT products.
To view the full publications in 2021 at