Research Theme 4

Atmospheric composition including greenhouse gases


Atmospheric composition influences the weather and air quality in the short term, at the local and regional scales. At the same time, it produces long-term climatic impacts at the regional and global scales. Accordingly, atmospheric composition research combines weather, air quality and climate across various temporal and spatial scales.

Atmospheric composition changes constantly, due to emissions, transport, chemical transformations, and the loss of trace gases and aerosols throughout the troposphere and stratosphere. The overarching objective of RT4 is to enhance our understanding of these processes’ effects on atmospheric composition and the impacts on weather, climate and air quality from the local to global scale (Figure 1). To achieve this goal, we will investigate traffic emissions, dust storms, vegetation fires and volcanic eruptions as natural experiments using high-end modelling, data assimilation and observation methods. The focus will be on regional interactions across subsystems and compartments of the Earth system that involve the atmospheric composition. Prime examples include the quantification of regional emissions and their impacts on regional air quality, weather and climate. In addition, we will study the implications for composition climate interactions and their regional manifestations (here, in particular, the interactions between the hydro-, bio- and atmosphere). Greenhouse gases (GHGs), in particular methane, provide a link between global climate change and regional manifestations of air composition changes.

Key questions for RT4:

  • How can we better quantify emissions in the coupled Earth system across compartments?
  • How can we better predict the atmospheric lifecycles of trace gases and aerosols?
  • How does atmospheric composition respond to and affect regional climate in the coupled Earth system?
  • How can we provide better estimates of GHG growth rates?

RT4 Speakers

Dr Ali Hoshyaripour (KIT)
Karlsruhe Institute of Technology (KIT)
Institute of Meteorology and Climate Research
Hermann-von-Helmholtz-Platz 1
76344 Eggenstein-Leopoldshafen
E-Mail: gholamali.hoshyaripour(at)

Dr Philipp Franke (FZJ)
Forschungszentrum Juelich GmbH, IEK-8
52425 Jülich
E-Mail: p.franke(at)