Global Climate Observing System
Project Information
1992 - present
gcos logo

The Global Climate Observing System (GCOS) was set up to assess the status of global climate observations on a regular base and to produce guidance for its improvement. GCOS expert panels dedicated to atmosphere, land and ocean maintain definitions of Essential Climate Variables (ECVs). These are either physical, chemical or biological variables or a group of linked variables that are required to systematically observe Earth’s changing climate. The observations of ECV’s supported by GCOS contribute to solving challenges in climate research and also provides the basis for climate services and adaptation measures. 

GCOS works through three panels:

  1. Atmospheric Observing Panel for Climate (AOPC);
  2. Ocean Observations Physics and Climate Panel (OOPC); and
  3. Terrestrial Observing Panel for Climate (TOPC).

GCOS also works through the GCOS Cooperation Mechanism (GCM), which provides direct support to observations.

GCOS is also supported via several networks that group various organisations/data centres dedicated to in situ monitoring, related to either atmospheric, ocean and terrestrial observations. More information about GCOS networks can be found here: https://gcos.wmo.int/en/networks

Project objectives

  • To coordinate global climate observations and facilitate their development and improvement
  • Monitor and publish the status of the observations of the Essential Climate Variables (ECVs)
  • Identify and publish what is needed to improve the system in implementation reports.

IGRAC's role in the project

The 19 ECVs that are coordinated by TOPC are divided in four categories: cryosphere, anthroposphere, biosphere and hydrosphere. ECV groundwater is one of the five ECVs that are part of the latter, together with river discharge, lakes, soil moisture and evaporation from land.

IGRAC has been contributing to GCOS since 2011, by providing expert advice on the ECV groundwater definition and requirements, and also by proposing and implementing action items of the programme. In particular, the Global Groundwater Monitoring Network (GGMN) was set up as a ‘network of networks’ to improve accessibility to groundwater monitoring data and information, which contributes to the goals of GCOS.

Moreover, IGRAC contributes to the Global Terrestrial Network for Hydrology (GTN-H).