in 2005 and 2018 (top panels) and absolute differences between retrieved NO2 columns in 2018 and 2005 (bottom panel). This QA4ECV dataset indicates a substantial reduction (up to 40%) in NO2 columns in the most polluted regions of Europe.
The ESA Climate Change Initiative (CCI) programme and its extension (CCI+) is the European response to requirements specified by the Global Climate Observing System (GCOS) for the systematic generation of Essential Climate Variables (ECVs).
It builds on long-term global earth satellite observational datasets, including Greenhouse Gases (GHGs), Ozone, Aerosols and Water Vapour.
The main objective of this project led by BIRA is the addition of trace gases that lead to the formation of ozone and aerosols, i.e. nitrogen dioxide (NO2), formaldehyde (HCHO), carbon monoxide (CO), sulfur dioxide (SO2) and ammonia (NH3) to reduce the gap between currently existing data sets and the GCOS requirements.
