The long-term research goal of the group is to understand which processes are responsible for observed variations of Earth’s atmospheric chemical composition. The chemical composition of the atmosphere directly impacts Earth’s radiative balance and consequently surface warming. It also defines the oxidation capacity of the global troposphere that determines the quality of air where we live and breathe.

We approach this goal mainly by developing novel mathematical models to reconcile new satellite observations with current knowledge. Often these models are too complex to resolve analytically so we tend to use computational approaches. Over the last decade or so we have also led the development of field experiments using research aircraft and ground-based instruments, and have designed science requirements for new aircraft and satellite instruments.

Our current research questions include:

• How do observed variations of atmospheric CO2 and CH4 respond to changes in climate?
  • What is the importance of different terrestrial processes in driving these atmospheric variations?
  • How can we distinguish between natural and anthropogenic drivers of the observed variations? 
• What drives observed changes in tropospheric chemistry and how do these affect surface air quality?
  • What is the relative importance of anthropogenic, biogenic, and pyrogenic emissions?

The methods we have developed to study Earth's atmosphere are also relevant to other planetary atmospheres. Through various collaborations we have begun to study the atmospheric chemical composition of Mars and exoplanets, and to interpret observed variations of brown dwarf light curves in terms of atmospheric features.

• What kind of atmospheric chemistry is sustainable within exoplanetary atmospheres?
  • How will new telescopic measurements challenge current understanding?
• What can we learn about the atmospheric chemistry on Mars from new satellite observations?
  • How is it influenced by surface fluxes?