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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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Gergely Bölöni, Bruno Ribstein, Jewgenija Muraschko, Christine Sgoff, Junhong Wei, and Ulrich Achatz

flow in a direct manner. In addition, wave breaking is accounted for in the WKB models by applying the saturation criterion [Eq. (27) ] and reducing the wave-action density proportionally to , as prescribed in Eq. (30) , if necessary. c. Steady-state WKB theory As mentioned in the introduction, current GW parameterization schemes are based on a steady-state WKB theory ( Nappo 2002 ; Coiffier 2011 ; Fritts and Alexander 2003 ; Kim et al. 2003 ). The assumption of a steady wave-action density

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

higher than 1 hPa were found to become unstable. Currently, we do not know why this is the case but will investigate this issue in the future. The initial and boundary conditions for the WRF Model are supplied by ECMWF operational analysis on 137 model levels with a temporal resolution of 6 h. Further details about the model setup can be found in the appendix . The complete WRF output is available every 60 and 30 min for the outer and inner domain, respectively. In addition, the momentary basic

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

to describe explicitly in current-resolution climate models, accounting for such small-scale GWs poses an important parameterization problem to atmospheric dynamics. With rising computing power available, an increasing number of studies of middle-atmosphere global GW dynamics uses models that can resolve a part of the GW spectrum ( Kawatani et al. 2009 , 2010a , b ; Brune and Becker 2013 ). This raises the question of whether the neglected subgrid-scale (SGS) GWs could impact the resolved flow

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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

dynamics, and their significant dependence on GW sources and the environments through which they propagate, pose major challenges for their parameterizations in global weather and climate models. Scientific interests and societal needs have motivated many previous studies of GWs from the stable boundary layer and troposphere, through the stratosphere and mesosphere, and into the thermosphere. Among the more important of these are the following: GWs pose hazards to people and property; examples include

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

. They found out that the WVD method using second-order Rossby number expansion in incompressible form is the optimal method as far as the energy of IGWs is concerned. The difference between the results of the WVD in compressible and incompressible forms can be related to the accuracy of the diabatic heating estimation, which may significantly affect the unbalanced flow. In the current work the WVD procedure of MMZP is further developed to incorporate in a different way the impact of forcing by

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Junhong Wei, Gergely Bölöni, and Ulrich Achatz

tides ( Ribstein et al. 2015 ; Ribstein and Achatz 2016 ). However, there is still no corresponding detailed validation of an IGW parameterization in a rotating compressible atmosphere against data from idealized wave-resolving simulations. This gives one of the motivations for the current study. More importantly, there are actually two available approaches for IGW parameterization, here called pseudomomentum scheme and direct scheme, respectively. The pseudomomentum scheme exploits the fact that

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

components of the atmospheric circulation system by adjusting free parameters of the different GW drag schemes (e.g., Garcia et al. 2017 ; Orr et al. 2010 ). Therefore, it is important to assess how well current convection-permitting GCMs are performing at reproducing observed features of GWMF and to understand how sensitive these features are to changes in model formulation as well as resolution. Moreover, a formal evaluation of the simulations against observational data is not a trivial task. We use

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