History of SOCAT

At the “Surface Ocean CO₂ Variability and Vulnerability” (SOCOVV) workshop at UNESCO, Paris in April 2007, co-sponsored by IOCCP, SOLAS, IMBER, and the Global Carbon Project, participants agreed to establish a global surface CO₂ data set that would bring together, in a common format, all publicly available fCO₂ data for the surface oceans. (The fugacity of carbon dioxide, or fCO₂, is the partial pressure of CO₂ (pCO₂) corrected for non-ideal behaviour of the gas.) This is an activity that has been called for by many international groups for many years, and has now become a priority activity for the marine carbon community.  This data set will serve as a foundation upon which the community will continue to build in the future, based on agreed data and metadata formats and standard 1st level quality-control procedures, building on earlier agreements established at the 2004 Tsukuba workshop on “Ocean Surface pCO₂ Data Integration and Database Development”. This activity also supports the SOLAS and IMBER science plans and their joint carbon implementation plan.

This data set is meant to serve a wide range of user communities and it is envisaged that, in the future, 2 distinct data products will be made available in this Surface Ocean CO₂ Atlas (SOCAT): 

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

The extended 1st level quality-controlled data set builds on the work started in 2001 as part of the EU ORFOIS project by Dorothee Bakker , which now continues as part of the EU CarboOcean project, where Benjamin Pfeil and Are Olsen (Bjerknes Centre for Climate research, University of Bergen, Norway)), have compiled the publicly-available surface CO₂ data held at CDIAC (Carbon Dioxide Information Analysis Center), WDC-MARE (World Data Center for Marine Environmental Sciences) and elsewhere into a common format database based on the IOCCP recommended formats for metadata and data reporting. This compilation currently includes data from more than 10 countries, producing an initial database composed of more than 2100 cruises from 1968 to 2007 with approximately 7.5 million measurements of various carbon parameters, available in a common format, 1st level quality-controlled data set.

At the SOCOVV meeting participants established regional working groups to identify data not yet included in the global standard data set by December 2007. Those groups are:

North Atlantic (including Arctic) – Ute Schuster (UEA, UK)

Tropical Atlantic -  Nathalie Lefevre (LOCEAN, France)

Pacific – Equatorial Pacific (30N-30S): Richard Feely (NOAA/PMEL, USA) and North Pacific (30N): Yukihiro Nojiri (NIES, Japan)

Southern Ocean – Bronte Tilbrook (CSIRO, Australia) and Nicolas Metzl (LOCEAN/IPSL, France)

Indian Ocean – V.V.S.S. Sarma (NIO, India)

Coastal Ocean – Arthur Chen (National Sun Yat-sen University, Taiwan) and Alberto Borges (U. Liege, Belgium)

Global group - Dorothee Bakker (UEA), Chris Sabine (NOAA/PMEL), Nicolas Metzl (LOCEAN/IPSL, France), Are Olsen, Benjamin Pfeil (both UiB, BCCR)