LEWIZ - Letzter Winter im zwanzigsten Jahrhundert

In connection with poleward breaking Rossby waves (Peters and Waugh, 1996, J. Atmos. Sci. 53: 3013-3031) tropospheric wind jets occur on the polar side of a ridge. Downstream of that jet in special regions of troposphere and stratosphere observations and simulations show the appearance of inertia-gravity waves. In the literature the forcing of these waves and their interaction with the polar vortex is associated with many physical processes und not clear yet. The contribution of inertia-gravity waves to the exchange and transport processes in the middle atmosphere is another aspect of the problem.

In order to go a first step in examining this phenomenon balloon measurements are organized to assess the wave structure. The pilot campaign of this research undertaking was conducted 17 - 19 December 1999. This last winter in the twentieth century was also a very windy one (remember the storms "Anatol" and "Lothar")... connected with much wave actitivity. Since then, many reserach has been done - mostly under windy and rainy conditions, like in the 1999 campaign. The name LEWIZ reminds on that...

In a later stage of the reserach undertaking these measurements were used for comparison with radar and lidar measurements at IAP in Mecklenburg. Simulations with mesoscale models will help to improve the understanding and to provide parameterisations of these processes. The research is spread over many activities devoted to different aspects of the problem covering the dynamics of  breaking Rossby waves, the generation, propagation and dissipation of inertia-gravity waves as well as the impact on weather phenomena. 

Scientific Steering Committee

<link _self einen externen link in einem neuen>Dieter H.W. Peters (PI), <link _self einen externen link in einem neuen>Peter Hoffmann, <link _self einen externen link in einem neuen>Michael Gerding, Christoph Zülicke

Projects

• Dec 1999: Pilot-LEWIZ: Pilot Campaign (funded by IAP)
• since 2000: Matrix-LEWIZ - Interaction of jet- and mountain-generated inertia-gravity waves (funded by IAP)
• Oct 2001 - Sep 2004: AFO2000-LEWIZ - Inertia-gravity waves and their connections to breaking Rossby waves (funded by BMBF)
• Jan 2005: ROMA/LEWIZ - Fate of inertia-gravity waves to the middle atmosphere (funded by DLR/IAP)
• Apr 2005 - Mar 2008: PIGW - Precipitation and Inertia-Gravity Waves (funded by DFG)
• Jan - Jul 2006: Cirrus-LEWIZ - Cirrus clouds in polewared breaking Rossby waves (funded by IAP)