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

. Besides a variety of ground-based instruments, the German Aerospace Center [Deutsches Zentrum für Luft- und Raumfahrt (DLR)] deployed the Falcon research aircraft, equipped with a coherent Doppler wind lidar (DWL) measuring horizontal and vertical wind speeds. A detailed summary of the GW-LCYCLE I campaign, including an overview of airborne observations, numerical simulations, and a discussion of the synoptic situation during the campaign period, has recently been provided by Wagner et al. (2017

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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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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

aircraft for global in situ measurements that enabled comparisons of GW responses to various sources (e.g., Nastrom and Fritts 1992 ; Fritts and Nastrom 1992 ). The Airborne Lidar and Observations of Hawaiian Airglow 1990 (ALOHA-90) and the Airborne Lidar and Observations of Hawaiian Airglow/Arctic Noctilucent Cloud Campaign 1993 (ALOHA/ANLC-93) measurement programs employed a lidar and ASI to sample GWs extending from the stratosphere into the MLT ( Hostetler et al. 1991 ; Hostetler and Gardner

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Stephen D. Eckermann, Jun Ma, Karl W. Hoppel, David D. Kuhl, Douglas R. Allen, James A. Doyle, Kevin C. Viner, Benjamin C. Ruston, Nancy L. Baker, Steven D. Swadley, Timothy R. Whitcomb, Carolyn A. Reynolds, Liang Xu, N. Kaifler, B. Kaifler, Iain M. Reid, Damian J. Murphy, and Peter T. Love

based on standard deviations of reanalyzed temperature differences with respect to independent MLT measurements (SOFIE and DLR lidar). By contrast, HYBRID runs weighted MLT observations and backgrounds more realistically via more representative errors in MLT temperature backgrounds from ensemble forecasts (see Fig. 10c ). These findings, while specific to the greater New Zealand region during the 2014 austral winter, nevertheless suggest a need to reinvestigate and recalibrate static error

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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

system north of the North Island, with a strong pressure gradient toward the south leading to a strong westerly flow (W regime; Fig. 2c ). The latter flow regime is prone to excite mountain waves and was found for 9.8% of the reanalyses. It prevailed for some consecutive days only at the end of July and beginning of August, after the aircraft deployment concluded [ground-based lidar and radiosonde observations continued through this period at Lauder; see Kaifler et al. (2015) and Ehard et al

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Stephen D. Eckermann, Dave Broutman, Jun Ma, James D. Doyle, Pierre-Dominique Pautet, Michael J. Taylor, Katrina Bossert, Bifford P. Williams, David C. Fritts, and Ronald B. Smith

has disappeared, with northeastern wave structure weakly visible but showing evidence of breakdown into smaller-scale instability structures. Correlative Na lidar observations were not available for these inbound transects. Fig . 18. Presentation of AMTM (a)–(c) airglow and (d)–(f) temperature imagery as in Fig. 5 , but showing results for Auckland Island transects from (left) 0945–1010, (center) 1015–1050, and (right) 1105–1125 UTC. b. Fourier solutions The 1000 UTC wave field in Fig. 17d

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

-based lidar observations in the lee of New Zealand’s Alps during DEEPWAVE revealed enhanced gravity wave activity in the stratosphere and mesosphere, which lasted about 1–3 days and alternated with quiescent periods ( Kaifler et al. 2015 ). The gravity wave forcing due to passing weather systems, the appearance of tropopause jets, and the middle atmosphere wave response were all observed with a similar frequency and duration of 2–4 days ( Fritts et al. 2016 ; Gisinger et al. 2017 ). The episodic nature

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

far to the southeast with significant amplitude at 15 km, but do at 45 km. This is consistent with the RF07 observations in Fig. 5 , which showed strong wave responses at 12 km only for the flight leg close to the terrain (cf. Figs. 5d and 5g ), whereas both AIRS and the lidar data showed strong wave responses near 45 km on all flight legs ( Figs. 5b,c,e,f ). Fig . 7. Plan views of w (color shading) and wind vectors at (a) 4 km (interval: 0.05 m s −1 ), (b) 9 km (interval: 0.02 m s −1 ), (c

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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

parameterizations ( Alexander et al. 2010 ). Satellite remote sensors, for example, suffer similar resolution constraints to global models, resolving only longer-wavelength components of the gravity wave spectrum ( Wu et al. 2006 ). These gaps motivated a Deep Propagating Gravity Wave Experiment (DEEPWAVE; Fritts et al. 2016 ) to acquire the most intensive observations to date of gravity wave generation, propagation and breakdown through deep layers of the atmosphere (see Fig. 2 of Fritts et al. 2016 ), using

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Nonlinear Simulations of Gravity Wave Tunneling and Breaking over Auckland Island

Tyler Mixa, Andreas Dörnbrack, and Markus Rapp

simulations from CARMA 2D with AIM observations . J. Geophys. Res. , 117 , D20104 , . 10.1029/2012JD017794 Chen , C. , and X. Chu , 2017 : Two-dimensional Morlet wavelet transform and its application to wave recognition methodology of automatically extracting two-dimensional wave packets from lidar observations in Antarctica . J. Atmos. Sol.-Terr. Phys. , 162 , 28 – 47 , . 10.1016/j.jastp.2016.10.016 Clark , T

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