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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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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

conclusions derived from this reanalysis research are summarized in section 6 . 2. High-altitude NAVGEM a. System overview The forecast-assimilation cycle of NAVGEM is depicted schematically in Fig. 2 . On the outer loop, the global forecast model, depicted with a red box at the top of Fig. 2 and described in section 2b(1) , issues a high-resolution deterministic forecast. The 0–9-h forecasts provide a background trajectory (red arrow) to the DAS. The DAS, depicted by the large teal box at the

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Christopher G. Kruse, Ronald B. Smith, and Stephen D. Eckermann

increasing orographic GWD significantly reduces the strength of the stratospheric polar vortex primarily by altering planetary Rossby wave propagation and drag. This result suggests that increasing parameterized orographic GWD in chemistry–climate models might reduce the cold-pole problem in free-running climate simulations. In this paper, the vertical propagation and attenuation of New Zealand mountain waves are studied using deep Weather Research and Forecasting (WRF) Model simulations with realistic

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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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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

), with wind speeds increasing with height into a strong southwesterly tropospheric jet. High-resolution regional forecasts centered over Auckland Island using the U.S. Naval Research Laboratory (NRL) Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS: Hodur 1997 ; Doyle et al. 2011 ) and Mountain Wave Forecast Model ( Eckermann et al. 2006b ) predicted wave generation and penetration of orographic gravity waves into the stratosphere. Fig . 2. (a) Time evolution of horizontal wind vectors

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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

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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Ronald B. Smith and Christopher G. Kruse

of aircraft data ( Smith et al. 2016 ; Smith and Kruse 2017 ) and a well validated set of high-resolution Weather Research and Forecasting (WRF) Model simulations ( Kruse et al. 2016 ). These resources allow us to propose and test a new hypothesis regarding wave drag on complex terrain. 3. Describing New Zealand’s terrain a. Volume and variance To analyze the South Island of New Zealand, we use the standard global 30-arc-s elevation (GTOPO30) (~1-km terrain) dataset transformed to a local

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Christopher G. Kruse and Ronald B. Smith

oscillations. This study goes beyond previous work by identifying many quadratic gravity wave diagnostic quantities, allowing many characteristics of gravity waves to be diagnosed and robustly quantified. The diagnostic method is tested in deep (80 Pa, ~45-km top) realistic Weather Research and Forecast (WRF) Model simulations forced by ECMWF grids. High-resolution simulations nested to 2-km resolution were completed for a deep mountain wave event, a shallow mountain wave event, and a convection

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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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