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Jannik Wilhelm, T. R. Akylas, Gergely Bölöni, Junhong Wei, Bruno Ribstein, Rupert Klein, and Ulrich Achatz

atmospheric applications is the second (hydrostatic) limit, for which the mesoscale-wave impact is the strongest. For instance, taking ( H m , L m ) = (1, 100) km and f / N * = 10 −2 , from (20) it is then found that ( H w , L w ) = (0.1, 1) km. Notably, this scale estimate is in good agreement with present-day local-area weather-forecast-code mesh distances (see section 1 ). For later reference, Table 1 provides an overview of the scales deduced in this section. It is worth noting that the

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Andreas Dörnbrack, Sonja Gisinger, Michael C. Pitts, Lamont R. Poole, and Marion Maturilli

reactions ( Teitelbaum and Sadourny 1998 ; Carslaw et al. 1998 ). Simulation of mesoscale mountain waves especially posed a challenge, and special methods such as linear wave prediction models and mesoscale forecast models were used in the past to predict their local formation (e.g., Dörnbrack et al. 1998 ; Eckermann et al. 2006 ). In this day and age, global operational NWP models use spatial resolutions, which hardly could be attained by limited-area models several years ago. For example, the

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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

global, mesoscale, and regional models that proved to be highly valuable and often quite accurate on shorter time scales for final flight planning (see Table 3 ). These models are now being applied in concert with DEEPWAVE data analysis efforts to answer the science questions posed in Table 1 . To aid DEEPWAVE research, a comprehensive DEEPWAVE data archive and management plan has been developed (see appendix A ). T able 3. Forecasting and research models. FV = finite volume. DNS = direct

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Martina Bramberger, Andreas Dörnbrack, Henrike Wilms, Steffen Gemsa, Kevin Raynor, and Robert Sharman

resolutions of less than 10 km. Thus, high-resolution global data are a valuable source for detecting and predicting mountain waves. Dörnbrack et al. (2017) showed that the recent increase of horizontal resolution of the Integrated Forecast System (IFS) of the European Centre for Medium-Range Weather Forecasts (ECMWF) led to a realistic simulation of wave-induced mesoscale temperature anomalies. Moreover, they concluded that the remarkable agreement of the simulated wave structure in the IFS short

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

altitude range, the lidar observations are complemented with temperatures simulated numerically by the Advanced Research version of the Weather Research and Forecasting (WRF) Model (ARW; Skamarock and Klemp 2008 ). Our goal is to determine the wave characteristics from the lower troposphere to the mesosphere. For this purpose, we combine and analyze the lidar temperature measurements and the validated mesoscale simulation results. Prerequisites of this approach are high-resolution numerical

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Markus Rapp, Bernd Kaifler, Andreas Dörnbrack, Sonja Gisinger, Tyler Mixa, Robert Reichert, Natalie Kaifler, Stefanie Knobloch, Ramona Eckert, Norman Wildmann, Andreas Giez, Lukas Krasauskas, Peter Preusse, Markus Geldenhuys, Martin Riese, Wolfgang Woiwode, Felix Friedl-Vallon, Björn-Martin Sinnhuber, Alejandro de la Torre, Peter Alexander, Jose Luis Hormaechea, Diego Janches, Markus Garhammer, Jorge L. Chau, J. Federico Conte, Peter Hoor, and Andreas Engel

second section, we describe the research aircraft and its instruments dedicated to the measurements of GW properties, along with the ground based measurements in the region. We will introduce the forecast model tools used for flight planning as well as reanalysis fields which are being used for the interpretation of atmospheric measurements. In the third section, we describe the prevailing meteorological conditions under which the flights were conducted. Mission overview and initial promising results

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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

-Interim and MLS to obtain the quasi-stationary PW1 amplitude. Note that this analysis is done by using a 10-day window shifted by 1 day to eliminate the influence of migrating waves such as tides. Vertical energy fluxes ( ) over the SI at 4- and 12-km altitude were computed from mesoscale simulations of the Weather Research and Forecasting (WRF) Model with a horizontal resolution of 6 km. The model was initialized and continuously guided by MERRA2 reanalyses. To compute the perturbations of pressure and

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Junhong Wei, Gergely Bölöni, and Ulrich Achatz

thus limit mesoscale predictability ( Zhang et al. 2007 ; Sun and Zhang 2016 ; Bierdel et al. 2018 ). The most important impact globally is because GWs can travel over large distances from their sources and transfer significant amounts of momentum and energy to high altitudes, which contributes to the forcing of the circulation and the variability of the middle atmosphere ( Holton and Lindzen 1972 ; Houghton 1978 ; Lindzen 1981 ; Dunkerton 1997 ; Richter et al. 2010 ; Limpasuvan et al. 2012

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Claudia Christine Stephan, Cornelia Strube, Daniel Klocke, Manfred Ern, Lars Hoffmann, Peter Preusse, and Hauke Schmidt

fine to capture a major fraction of the GW spectrum (e.g., Beres et al. 2004 ; Choi and Chun 2011 ). GWs in high-resolution (~4 km) simulations of regional mesoscale models, such as the Weather Research and Forecasting (WRF) Model, can have a high degree of realism ( Grimsdell et al. 2010 ; Orr et al. 2015 ; Stephan and Alexander 2015 ; Stephan et al. 2016 ). In the light of ever-increasing computational capabilities, the above challenges have served as a strong motivation to devise global

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Mohammad Mirzaei, Ali R. Mohebalhojeh, Christoph Zülicke, and Riwal Plougonven

this fuzziness, there is no exact balance and no exact wave–vortex decomposition. Given the constraints set by this fundamental limitation, the waves and vortical flows can only be decomposed in an approximate sense, which can be sufficient for practical purposes. The current work aims to compare the measures of IGW activity coming from the HDA with those of the WVD methods in the idealized numerical simulations of the dry and moist baroclinic instability by the Weather Research and Forecasting

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