Atmospheric waves

Atmospheric waves are motions of air in the Earth’s atmosphere which have different spatial (meters to thousands of kilometers) and temporal scales (minutes to weeks). They can impact the wind, density, pressure or temperature fields and can be identified as fluctuations of these parameters. Waves are mainly excited in the troposphere and stratosphere and propagate vertically and also horizontally. While propagating, waves transport energy and momentum from their source regions across the atmosphere and can dissipate under special circumstances. The breaking of waves is associated with the transmission of energy and momentum to the background atmosphere such that atmospheric waves contribute crucially to the coupling of different atmospheric layers.

The most important types of waves which are subject of the research at IAP are planetary Rossby waves, tides, and gravity waves. While gravity waves are of local/regional dimension the other two wave types are of global extent. Planetary Rossby waves have the latitudinal variation of the Coriolis force as restoring force. Tides include mainly thermally excited solar tides, generated by differential solar heating, as well as gravitationally excited lunar tides. Gravity waves are restored by the equilibrium between buoyancy and gravity and only exist in a stable stratified atmosphere. The properties, propagation, and impact of these waves on the background are investigated by using a combination of local radar and lidar instruments supported by global satellite observations (e.g.,  MLS) and model studies (e.g., KMCMMERRA).

Publications

  • P. Hoffmann, E. Becker, W. Singer und M. Placke, Seasonal variation of mesospheric waves at northern middle and high latitudes, J. Atmos. Solar-Terr. Phys., 72, 1068-1079, doi:10.1016/j.jastp.2010.07.002, 2010.
  • M. Placke, P. Hoffmann, E. Becker, Ch. Jacobi, W. Singer und M. Rapp, Gravity wave momentum fluxes in the MLT-Part II: Meteor radar investigations at high and midlatitudes in comparison with modeling studies, J. Atmos. Solar-Terr. Phys., 73, 911-920, doi:10.1016/j.jastp.2010.05.007, 2011.
  • M. Placke, P. Hoffmann, M. Gerding, E. Becker und M. Rapp, Testing linear gravity wave theory with simultaneous wind and temperature data from the mesosphere, J. Atmos. Solar-Terr. Phys., 93, doi:10.1016/j.jastp.2012.11.012, 2013.
  • G. Stober, S. Sommer, M. Rapp und R. Latteck, Investigation of gravity waves using horizontally resolved radial velocity measurements, Atmos. Meas. Tech., 6, 2893-2905, doi:10.5194/amt-6-2893-2013, 2013.
  • Placke, M., P. Hoffmann, R. Latteck, and M. Rapp (2015), Gravity wave momentum fluxes from MF and meteor radar measurements in the polar MLT region, J. Geophys. Res. Space Physics, 120, 736-750, doi:10.1002/2014JA020460.