GCOS History

GCOS was established in 1992 to ensure that the observations and information needed to address climate-related issues are obtained and made available to all potential users. It is co-sponsored by the:

  • World Meteorological Organization (WMO),
  • Intergovernmental Oceanographic Commission (IOC) of United Nations Educational, Scientific and Cultural Organization (UNESCO),
  • United Nations Environment Programme (UN Environment Programme), and
  • International Council for Science (ISC).
Logos of GCOS, WMO, UNESCO IOC, International Science Council, and UN Environment Programme displayed in a row.

The terms of reference for the co-sponsorship are detailed in the GCOS Memorandum of Understanding. The original version was signed in 1992 and was updated in 1998.

GCOS Memorandum of Understanding (1992)

GCOS Memorandum of Understanding (1998)


The GCOS programme stimulates, encourages, coordinates and facilitates the taking of needed observations by national or international organizations to support their own requirements and common goals. It provides an operational framework for integrating and enhancing the observational systems of participating countries and organizations into a comprehensive system focused on the requirements for climate issues. The GCOS programme does not directly make observations nor generate data products.

GCOS Milestone Conclusions, Resolutions and Decisions (1997 – 2019)

Final Report of the Joint Study Group GCOS (GCOS-246)

GCOS Milestones

  • 1992 Establishment of GCOS as an outcome of the Second World Climate Conference (1990)
  • 1995 Plan for the Global Climate Observing System (GCOS), Publication No. GCOS-14 GCOS Plan for Space-based Observations, Publication No. GCOS-15
  • 1998 Report on the Adequacy of the Global Climate Observing Systems – United Nations Framework Convention on Climate Change, Publication No. GCOS-48, COP-4, Buenos Aires, Argentina
  • 2003 Second Report on the Adequacy of the Global Observing Systems for Climate in Support of the United Nations Framework Convention on Climate Change (UNFCCC), Publication No. GCOS-82, COP-9, Milan, Italy
  • 2004 Implementation Plan for the Global Observing System for Climate in Support of the UNFCCC, Publication No. GCOS-92, COP-10, Buenos Aires, Argentina
  • 2006 Systematic Observation Requirements for Satellite-based Products for Climate – Supplemental Details to the Satellite-based Component of the Implementation Plan for the Global Observing System for Climate in Support of the UNFCCC, Publication No. GCOS-107
  • 2009 Progress Report on the Implementation of the Global Observing System for Climate in Support of the UNFCCC 2004–2008, Publication No. GCOS 129, COP-15, Copenhagen, Denmark
  • 2010 Implementation Plan for the Global Observing System for Climate in Support of the UNFCCC (2010 Update), Publication No. GCOS-138, COP-16, Cancun, Mexico
  • 2015 Status of the Global Observing System for Climate, Publication No. GCOS-195
  • 2016 The Global Observing System for Climate: Implementation Needs, Publication No. GCOS 200, and COP-22 Decision
  • 2021 The Global Climate Observing System 2021: the GCOS Status Report, Publication No. GCOS 240
  • 2022 The 2022 GCOS Implementation Plan, Publication No. GCOS 244 and SBSTA Decision FCCC/SBSTA/2022/L.20/Add.1