Implementing a GEOSS implicitly requires also an assessment of the current situation. We all are accustomed to the assessments of the state of scientific knowledge with respect to climate change and its causes provided frequently by the IPCC. Up to now, no similar assessment process is established for the state of Earth observations, although it would be very important to have.

GEO can step in and close this gap. For that, GEO would have to establish a well defined assessment process with the goal to identify significant gaps in the observing system, which will change over time as the applications develop based on a better understanding of the relevant processes in the Earth system and improved models that will be able to make use of more observational constraints.