The atmosphere is governed by a complex interaction of various processes relating to radiation, dynamics and chemistry. On their part, the dynamics are dominated by wave phenomena of global, continental and regional scales, such as planetary waves, gravity waves and infrasound, which transport energy and momentum on all these scales. Waves thus have a significant influence on the structure of the atmosphere, and for characterizing the condition of the atmosphere it is essential that they be adequately taken into account in climate and atmosphere models. Because the atmosphere is a coupled system, it is not appropriate to limit considerations to the troposphere; it is also necessary to study the processes taking place in the mid-atmosphere (10-100 km). Atmospheric waves also have larger amplitudes there because of the reduced density of the air, and so they can be more easily investigated.
The Dynamics team is involved in hardware development, as well as data analysis (using, for example, spectral analysis) and modeling (raytracing).
The Dynamics team has the goal of helping to improve the forecast quality of climate and atmosphere models and the quality assurance of value-added products. The focus is on developing easy-to-interpret indices which make it possible to confirm the representation of atmospheric dynamics in models and in the data products based on these models. Basic research on the interactions of the different waves among themselves (such as triads) and with the background flow is undertaken wherever there is a lack of relevant knowledge. An expanded knowledge base in this area will continue to be put to use to contribute to improving the forecasting of extreme weather events based on measurement of the atmospheric waves which they emit. Meeting all these goals requires the use of global data sets, which can only be produced from satellite data. Because of the small scale of gravity and infrasound waves they cannot be completely detected by satellites, so it is necessary to have supplementary point measurements, obtained, for example, with the help of rockets, radiosondes, or DFD’s infrared spectrometers GRIPS (GRound-based Infrared P-branch Spectrometer) and TANGOO (Tilting-filter spectrometer for Atmospheric Nocturnal Ground-based Oxygen & hydrOxyl emission measurements). These instruments, developed and operated by the Dynamics team, make use of the so-called airglow between 80 km and 100 km altitude and provide temperature values with temporal resolutions from several tens of seconds up to several minutes.
The Dynamics team together with its spectrometers and expertise in the area of atmospheric waves is involved in the international NDMC network (Network for the Detection of Mesopause Change). NDMC was founded in 2007 and is being coordinated by DLR’s Atmosphere unit, with assistance from the Free State of Bavaria and in consultation with the University of Buenos Aires, Argentina.