As the impacts of a warming climate become more evident, there is an ever-increasing demand for more detailed information on climate change, both to explain and project changes and to help planning and implementing adaptation and mitigation.

GCOS has now released its latest report on the state of global climate observing system. The report identifies improvements in our observational capabilities and highlights outstanding issues and gaps. The findings are presented for each Essential Climate Variable (ECV) and specific action identified in the last GCOS Implementation Plan. This report is being submitted to the UNFCCC for consideration at COP26 in Glasgow.

Since 2015, satellite observations have improved, allowing near-global coverage of many variables and providing open access to the data. There also have been many improvements to surface-based observations of individual ECVs across the atmospheric, ocean and terrestrial domains, with new technologies and approaches being developed, especially in the oceans. Archiving and online access to the observations and derived information has improved.

Overall, there are four main areas still needing improvements:

• ensuring the sustainability of observations,
• addressing of gaps in the system,
• ensuring permanent, free and unrestricted access to the observations,
• increasing support for policies driven by the UNFCCC Paris Agreement.

GCOS regularly reviews the state of global climate observations and releases reports on its findings. This is the fifth time GCOS has prepared a full report on the state of global climate observations. GCOS Status reports are followed by an Implementation Plan that outlines the improvements that are needed in the global system. Work is already underway to produce the next GCOS Implementation Plan in 2022, responding to the findings of this 2021 Status Report.