The mesosphere and lower thermosphere at an altitude of approximately 50-200 km form the middle and upper part of Earth's atmosphere that is still relatively unexplored and yet is of great social relevance. The main factors contributing to this are its still limited continuous accessibility and the increasing use of near-Earth space.
Through new insights into the dynamics of this region, the IAP contributes significantly to our understanding of the entire atmosphere and its transition processes to space. To this end, it uses and develops optical and radio wave remote sensing systems, as well as direct measurements and model simulations.
The IAP's research methods and objectives are summarised in its scientific framework programme (in English). The focus of scientific and experimental work is on:
- Research into the mesosphere and lower thermosphere
- Coupling of the mesosphere and lower thermosphere to lower and upper atmospheric layers
- Long-term changes in the mesosphere and lower thermosphere and adjacent regions
The MLT is an area of high interest. It forms the transition region between our atmosphere and space. It is thus characterised by complex interactions between gaseous fluids, chemical composition and electrodynamic processes. Due to limited accessibility, describing the region's state and dynamics is an exciting and still explorative scientific challenge. IAP is dedicated to advance the understanding of the MLT by cutting-edge observational infrastructure and sophisticated modelling.
Earth’s atmosphere is classified in layers which continuously exchange energy and mass. Its full understanding can only be achieved by a comprehensive approach. Therein, the MLT plays a particular role being largely influenced by near-surface meteorology and by high energetic solar radiation. It is the host of extraordinary phenomena such as noctilucent clouds and auroras, which result from these vertical couplings. Knowledge of the vertical coupling processes is fundamental in approaching a whole atmosphere understanding. IAP is dedicated to increase this process understanding with particular focus and expertise in the MLT region.
The MLT is a climate sensitive region which, for example, currently experiences cooling due to increasing abundance of carbon dioxide affecting different states and processes there. Assessing our atmosphere’s current state and its trends, as well as estimating potential evolutions is only possible with the knowledge of earlier states and trends. IAP runs long-term observations in Germany and northern Norway of upper atmospheric electron content, atmospheric altitudes at the MLT and noctilucent clouds for a few to several decades. By analysing the time series and complementing it with modelling, IAP contributes to describing long term environmental trends.