Research Group Middle Atmosphere Dynamics

Head: Dr. Hella Garny

Mean temperature of the atmosphere during northern winter and the mean global circulation of the middle atmosphere (schematically, black arrows)

The middle atmosphere (i.e. the atmospheric layer extending from about 10 to 100 km) is known to influence surface weather and climate, and its role in the climate system is increasingly being appreciated. The research group MACClim (“The middle atmosphere in a changing climate (MACClim) - Reconciling observed and modeled changes in the middle atmospheric circulation and their impacts on chemistry and climate”) investigates the global dynamics of the middle atmosphere in a changing climate. Processes relevant to the global circulation in the middle atmosphere (the “Brewer-Dobson circulation”) are investigated with the help of a global climate model.

The research topics of our group are:

  • Transport processes relevant to the Brewer-Dobson circulation: mixing and residual circulation.
  • Uncertainties in the simulation of global dynamics in the middle atmosphere due to the simplified representation of gravity waves.
  • Transport characteristics derived from tracers.
  • Impact of the middle atmosphere circulation on active trace gases.
  • Dynamical coupling of the middle atmosphere circulation to the circulation of the troposphere.

We mainly use the global chemistry-climate model EMAC for our studies. Model simulations are compared to observational data from both satellite-bound instruments (e.g. MIPAS) and to in-situ measurements of trace gases.

Furthermore, we combine the fully coupled global model with

  • an idealized model for the simulation of global dynamics, that we develop based on EMAC. This is essential for advancing the mechanistic understanding and untangling cause-effect relationships of the dynamical forcing of the middle atmospheric circulation.
  • the mesoscale model COSMO embedded in EMAC, which will be used to study processes that are below the resolution of the global model.