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

.14) ] from the total divergent wind and attribute the resulting divergent wind to jets in the tropical region. However, a caution is needed here. One should note that source due to convection based on the low-pass-filtered data cannot cover the small-scale parameterized convection. Therefore, the resulting divergent wind may also contain the effects of the heat sources associated with small-scale convection. The generation of large shearing motion in the vertical direction is thought to be responsible

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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

. REFERENCES Alexander , M. J. , and L. Pfister , 1995 : Gravity wave momentum flux in the lower stratosphere over convection . Geophys. Res. Lett. , 22 , 2029 – 2032 , doi: 10.1029/95GL01984 . Alexander , M. J. , and A. W. Grimsdell , 2013 : Seasonal cycle of orographic gravity wave occurrence above small islands in the Southern Hemisphere: Implications for effects on the general circulation . J. Geophys. Res. Atmos. , 118 , 11 589 – 11 599 , doi: 10.1002/2013JD020526 . Alexander , M. J

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Christoph Zülicke, Erich Becker, Vivien Matthias, Dieter H. W. Peters, Hauke Schmidt, Han-Li Liu, Laura de la Torre Ramos, and Daniel M. Mitchell

and Becker (2013) . For the present study, the model run was prolonged with identical settings. This dataset is included in the present study as an example for a stationary mechanistic simulation of the general circulation on a time-invariant background field [i.e., without a seasonal cycle and quasi-biennial oscillation (QBO)] and resolved GWs that are mainly generated in the extratropical storm tracks (i.e., without any GW drag parameterization). The Hamburg Model of the Neutral and Ionized

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

diabatic heating on unbalanced flow in the idealized moist simulation of BCWs by the WRF Model. To this end, we derive a new WVD based on balance relations of the Rossby number expansion that includes an explicit expression of forcing by diabatic heating in which both compressible and nonhydrostatic effects are explicitly taken into account. In particular, we explore the consequences of assuming both the spatial-scale separation between IGWs and balanced flows and the validity of the compressible

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

. Rosenlof , 1996 : Nonstationary gravity wave forcing of the stratospheric zonal mean wind . J. Geophys. Res. , 101 , 23 465 – 23 474 , https://doi.org/10.1029/96JD02197 . 10.1029/96JD02197 Alexander , M. J. , and A. W. Grimsdell , 2013 : Seasonal cycle of orographic gravity wave occurrence above small islands in the Southern Hemisphere: Implications for effects on general circulation . J. Geophys. Res. Atmos. , 118 , 11 589 – 11 599 , https://doi.org/10.1002/2013JD020526 . 10

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

1. Introduction Internal gravity waves (GWs) play a significant role in atmospheric dynamics on various spatial scales ( Fritts and Alexander 2003 ; Kim et al. 2003 ; Alexander et al. 2010 ; Plougonven and Zhang 2014 ). Already in the lower atmosphere GW effects are manifold. Examples include the triggering of high-impact weather (e.g., Zhang et al. 2001 , 2003 ) and clear-air turbulence ( Koch et al. 2005 ), as well as the effect of small-scale GWs of orographic origin on the predicted

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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

trend of the seasonal warming in the stratosphere from June to August that is less pronounced in the MLS data. The differences in the vertical profiles might occur as a result of the much lower temporal and horizontal resolution of MLS compared to ERA-Interim. Small-scale effects like GWs are likely not well represented in the MLS measurements since the temporal resolution is 1 day at one place. The zonal wind profiles show the characteristic properties with a tropopause jet of U MAX ≈ 30 m s −1

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

, 42 – 68 , doi: 10.1175/WAF901.1 . 10.1175/WAF901.1 Fritts , D. C. , and Coauthors , 2016 : The Deep Propagating Gravity Wave Experiment (DEEPWAVE): An airborne and ground-based exploration of gravity wave propagation and effects from their sources throughout the lower and middle atmosphere . Bull. Amer. Meteor. Soc. , 97 , 425 – 453 , doi: 10.1175/BAMS-D-14-00269.1 . 10.1175/BAMS-D-14-00269.1 Geelmuyden , H. , 1885 : Iridescent clouds . Nature , 31 , 264 , doi: 10.1038/031264c0 . 10

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

calculating the wavelet coefficients. The cone of influence (COI) is the region of the wavelet spectrum where edge effects become important. Outside the COI, the spectral amplitude could be reduced because of the zero padding ( Torrence and Compo 1998 ). The absolute values of the individual spectra are averaged over a given time period to retrieve the mean spectrum for an observational period. Dominant vertical wavelengths are derived by examining the local maxima in the global mean wavelet spectrum

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

June and are kept constant throughout each simulation, covering 48 h. In the 2D WRF Model, open boundary conditions are used in flow direction. Note that horizontal winds are projected to a wind direction of 300° ( ), which is the direction of the Mt-A-2b transect ( Fig. 1 ). All idealized simulations are run without moisture and radiation effects. From both the WRF and the in situ flight-level data, vertical energy and momentum fluxes are calculated according to the method of Smith et al. (2008

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