Online — GCOS, the Global Climate Observing System, is a joint undertaking of:
- The World Meteorological Organization (WMO),
- The Intergovernmental Oceanographic Commission (IOC) of the United Nations Educational Scientific and Cultural Organization (UNESCO),
- The United Nations Environment Programme (UNEP) and
- The International Council for Science (ICSU).
Its goal is to provide comprehensive information on the total climate system, involving a multidisciplinary range of physical, chemical and biological properties, and atmospheric, oceanic, hydrological, cryospheric and terrestrial processes.
It is built on the WMO Integrated Global Observing System (WIGOS), the IOC-WMO-UNEP-ICSU Global Ocean Observing System (GOOS), the UN Food and Agriculture Organization (FAO)-UNEP-UNESCO-ICSU Global Terrestrial Observing System (GTOS) and a number of other domain-based and cross-domain research and operational observing systems.
It includes both in situ and remote sensing components, with its space based components coordinated by the Committee on Earth Observation Satellites (CEOS) and the Coordination Group for Meteorological Satellites (CGMS).
GCOS is intended to meet the full range of national and international requirements for climate and climate-related observations.
As a system of climate-relevant observing systems, it constitutes, in aggregate, the climate observing component of the Global Earth Observation System of Systems (GEOSS)
The Global Observing System is an extremely complex undertaking, and perhaps one of the most ambitious and successful instances of international collaboration of the last 100 years. It consists of a multitude of individual observing systems owned and operated by a plethora of national and international agencies with different funding lines, allegiances, overall priorities and management processes.