WMO uses a list of 7 state-of-the-climate indicators that are based on the 54 Global Climate Observing System (GCOS) Essential Climate Variables, including surface temperature, ocean heat content, atmospheric carbon dioxide (CO2 ), ocean acidification, sea level, glacier, and Arctic & Antarctic sea ice extent. Additional indicators are usually assessed to allow a more detailed picture of the changes in the respective domain.
Listed datasets with a green checkmark icon have been assessed.