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Stephen D. Eckermann, James D. Doyle, P. Alex Reinecke, Carolyn A. Reynolds, Ronald B. Smith, David C. Fritts, and Andreas Dörnbrack

procedures for generating and analyzing gravity wave products were tested as part of a larger coordinated DEEPWAVE “dry run” from 5 to 18 August 2013. Immediately after download and postprocessing, AIRS gravity wave products were plotted and then uploaded as image files to an online field catalog, where the science team could access this imagery through a web tool, along with many other products, such as forecasts from a small subset of operational NWP systems. The DEEPWAVE science team convened daily

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David C. Fritts, Ronald B. Smith, Michael J. Taylor, James D. Doyle, Stephen D. Eckermann, Andreas Dörnbrack, Markus Rapp, Bifford P. Williams, P.-Dominique Pautet, Katrina Bossert, Neal R. Criddle, Carolyn A. Reynolds, P. Alex Reinecke, Michael Uddstrom, Michael J. Revell, Richard Turner, Bernd Kaifler, Johannes S. Wagner, Tyler Mixa, Christopher G. Kruse, Alison D. Nugent, Campbell D. Watson, Sonja Gisinger, Steven M. Smith, Ruth S. Lieberman, Brian Laughman, James J. Moore, William O. Brown, Julie A. Haggerty, Alison Rockwell, Gregory J. Stossmeister, Steven F. Williams, Gonzalo Hernandez, Damian J. Murphy, Andrew R. Klekociuk, Iain M. Reid, and Jun Ma

shown in Fig. 1 (bottom). Figure 2 shows the extent of all DEEPWAVE measurements in altitude and latitude. F ig . 2. North–south cross section showing the types of airborne and ground-based instruments contributing to DEEPWAVE measurements and their coverage in latitude and altitude. DEEPWAVE began with a test flight-planning exercise from 1 to 10 August 2013 to gain experience with forecasting and flight planning and to assess the reliability of such forecasts in preparation for the real field

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Benjamin Witschas, Stephan Rahm, Andreas Dörnbrack, Johannes Wagner, and Markus Rapp

( Baumgarten 2010 ; Hildebrand et al. 2012 ). For instance, Kaifler et al. (2015) used temperature perturbations derived from Rayleigh lidar measurements (28–76 km altitude) to characterize GWs over New Zealand and showed that enhanced GW potential energy densities in the mesosphere are surprisingly associated with mountain waves excited by only low to moderate tropospheric wind speeds between 2 and 12 m s −1 . Although the aforementioned lidar technique represents a valuable tool to characterize GWs

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Sonja Gisinger, Andreas Dörnbrack, Vivien Matthias, James D. Doyle, Stephen D. Eckermann, Benedikt Ehard, Lars Hoffmann, Bernd Kaifler, Christopher G. Kruse, and Markus Rapp

. Data sources Operational analyses of the Integrated Forecast System (IFS) of the European Centre for Medium-Range Weather Forecasts (ECMWF) are used to provide meteorological data to characterize the atmospheric situation. The 6-hourly operational analysis and hourly forecast fields of the IFS cycle 40r1 have a horizontal resolution on the reduced linear Gaussian grid of about 16 km (T L 1279) and 137 vertical model levels (L137) from the ground to ~80 km (0.01 hPa) with layer thicknesses gradually

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Benedikt Ehard, Peggy Achtert, Andreas Dörnbrack, Sonja Gisinger, Jörg Gumbel, Mikhail Khaplanov, Markus Rapp, and Johannes Wagner

higher altitudes (e.g., Siskind 2014 ). Thereby, the wind field and the thermal structure of the middle atmosphere are modified (e.g., Lindzen 1981 ; Holton and Alexander 2000 ). Internal gravity waves have been measured and analyzed with a large variety of active and passive remote sensing techniques as well as with in situ observations. These observational tools include airborne and ground-based lidars (e.g., Alexander et al. 2011 ; Dörnbrack et al 2002 ; Rauthe et al. 2008 ; Williams et al

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Tanja C. Portele, Andreas Dörnbrack, Johannes S. Wagner, Sonja Gisinger, Benedikt Ehard, Pierre-Dominique Pautet, and Markus Rapp

analyses valid at 0000, 0600, 1200, and 1800 UTC and 1-hourly high-resolution forecasts at intermediate lead times (+1, +2, +3, +4, +5, +7, +8, +9, +10, and +11 h) of the 0000 and 1200 UTC forecast runs of the Integrated Forecast System (IFS) of the European Centre for Medium-Range Weather Forecasts (ECMWF) are further used to visualize the temporal evolution of the upstream conditions at 44.20°S, 167.50°E ( Fig. 1 ). The IFS cycle 40r1 has a horizontal resolution of about 16 km, 137 vertical model

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Qingfang Jiang, James D. Doyle, Stephen D. Eckermann, and Bifford P. Williams

; Doyle et al. 2011 ) were applied to the DEEPWAVE study area to provide real-time forecast guidance during the field campaign period ( Fritts et al. 2016 ). COAMPS is a fully compressible, nonhydrostatic terrain-following mesoscale model. The finite-difference schemes are of second-order accuracy in time and space in this application. The boundary layer and free-atmospheric turbulent mixing and diffusion are represented using a prognostic equation for the turbulence kinetic energy budget following

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Nonlinear Simulations of Gravity Wave Tunneling and Breaking over Auckland Island

Tyler Mixa, Andreas Dörnbrack, and Markus Rapp

, 2006a : Fourier-ray modeling of short-wavelength trapped lee waves observed in infrared satellite imagery near Jan Mayen . Mon. Wea. Rev. , 134 , 2830 – 2848 , . 10.1175/MWR3218.1 Eckermann , S. D. , A. Dörnbrack , H. Flentje , S. B. Vosper , M. J. Mahoney , T. P. Bui , and K. S. Carslaw , 2006b : Mountain wave–induced polar stratospheric cloud forecasts for aircraft science flights during SOLVE/THESEO 2000 . Wea. Forecasting , 21 , 42

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