The objective of TROPOMI is to provide accurate and timely observations of key species for atmospheric composition, for services on air quality, climate and the ozone layer. The daily global observations of TROPOMI will be used for improving air quality forecasts as well as for monitoring the concentrations of atmospheric constituents over multiple years. Trend monitoring is very important to verify that measures implemented to control the emissions to the atmosphere are effective. In addition, TROPOMI will also contribute to services on volcanic ash for aviation safety, for services warning for high levels of UV radiation that can cause skin damage, and to the numerical weather forecast. Scientists will use the data of the S5p mission to improve our knowledge on important chemical and dynamical processes in the atmosphere.

Air pollution, climate change and depletion of the ozone layer have in common that they are caused by changes in the composition of the atmosphere. Sources and sinks, chemical conversion, and transport of gases and aerosols determine the composition of the atmosphere, as shown in the figure below.

Composition diagram showing the evolution/cycles of various elements in Earth's atmosphere. Source: Strategic Plan for the U.S. Climate Change Science Program.