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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

). Fritts et al. (2016) review the planning, execution, and initial results of DEEPWAVE. One of the many scientific objectives of DEEPWAVE was to acquire gravity wave observations to test recent ideas that gravity waves generated by small island terrain in the Southern Ocean significantly influence the large-scale momentum budget of the middle atmosphere in austral winter. This idea first arose when Alexander et al. (2009) analyzed radiances acquired by the Atmospheric Infrared Sounder (AIRS) on 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

“hotspot” region of New Zealand ( Fig.1 , top) during austral winter, when strong vortex edge westerlies provide a stable environment for deep GW propagation into the MLT. T able 1. Science goals. F ig . 1. (top) DEEPWAVE region of airborne and ground-based measurements over New Zealand, Tasmania, the Tasman Sea, and the Southern Ocean. Colors show the GW hotspots in AIRS rms temperature for Jun–Jul 2003–11 at 2.5 hPa. (bottom) Ground-based instruments contributing to DEEPWAVE in New Zealand and

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Ronald B. Smith, Alison D. Nugent, Christopher G. Kruse, David C. Fritts, James D. Doyle, Steven D. Eckermann, Michael J. Taylor, Andreas Dörnbrack, M. Uddstrom, William Cooper, Pavel Romashkin, Jorgen Jensen, and Stuart Beaton

dynamics and predictability. The DEEPWAVE project took place in June and July 2014 in the New Zealand region. In this paper, we focus on the flight-level data from the NSF/NCAR Gulfstream V (GV) aircraft. In 26 missions, the GV carried out 97 legs over the Southern Alps of New Zealand and 150 legs over the Tasman Sea and Southern Ocean ( Fig. 1 ). A typical leg length and altitude are 350 and 12.1 km, respectively. Flight-level sampling was done at 1 Hz (240 m) and 25 Hz (10 m). Here we take a

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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

gravity wave climatologies, eventually leading to Christchurch, New Zealand, being selected as the operating base for a DEEPWAVE NGV deployment. We present a selection of the climatological AIRS-based research that informed this choice. Figs. 4a and 4b show terrain and regional landmarks in and around New Zealand and over the Southern Ocean. Plots below show σ T B j derived from 3 and 80 hPa AIRS radiances, averaged throughout June and July from 2003 to 2011. The 80 hPa σ T B j in Figs. 4e and 4

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

in the stratosphere was documented by several groups using observations from satellite-mounted sensors (e.g., Wu and Waters 1996 ; Eckermann and Preusse 1999 ; Jiang et al. 2002 ; Hendricks et al. 2014 ). Local maxima in stratospheric wave perturbation amplitudes, or “hot spots” ( Hoffmann et al. 2013 ), were found in the vicinity of major barriers such as the Southern Andes and Antarctic Peninsula, implying orographic origins. However, some maxima are located over the Southern Ocean far from

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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

investigate the different sources of gravity waves under favorable atmospheric conditions for deep vertical propagation, a climatological local maximum in gravity wave (GW) activity (a so-called hotspot) was sought in the Southern Hemisphere (SH) during austral winter. Besides the southern Andes, the Antarctic Peninsula, Tasmania, and other small islands in the Southern Ocean, the South Island (SI) of New Zealand constitutes one of several hotspots of stratospheric gravity wave activity in the Southern

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Johnathan J. Metz, Dale R. Durran, and Peter N. Blossey

lidar at Lauder. Hokitika is upstream of the spine of the Southern Alps and is therefore upstream of any trapped waves, and, as noted in Kaifler et al. (2015) , the Rayleigh lidar is unreliable below 28-km altitude due to potential contamination by stratospheric aerosols. Therefore, we regrettably proceed with analysis of this case without observations. a. Simulation configuration The simulation was conducted using version 3.8.1 of the Advanced Research version of WRF (WRF-ARW) Model ( Skamarock et

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Christopher G. Kruse and Ronald B. Smith

-generated gravity wave events within 6- and 2-km-resolution WRF simulations ( appendix A ), respectively, are presented in this section. a. Jet-generated gravity waves Gravity waves events are quite apparent and frequent in midstratospheric analyses of vertical velocity and temperature over the Southern Ocean south of New Zealand. This is a particularly stormy region, with frequent midlatitude cyclones and high-amplitude upper-tropospheric waves. Within the complex jet structures in the upper troposphere, flow

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Ronald B. Smith and Christopher G. Kruse

, hereinafter S16 ) provides an improved dataset for gravity wave spectral studies over mountains. All the standard physical variables (e.g., u , υ , w , p , and T ) were measured independently and redundantly. The Southern Alps of New Zealand are surrounded by ocean and are therefore compact. Spectral and physical analyses are easier if the disturbance is compact. The Southern Alps have rapid tectonic uplift and erosion rates ( Williams 1991 ) and one of the most rugged terrains in the world. Small

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

modelling of mountain waves over the Southern Alps of New Zealand . Quart. J. Roy. Meteor. Soc. , 126 , 2765 – 2788 , . 10.1002/qj.49712656909 Liu , Y. , X. San Liang , and R. H. Weisberg , 2007 : Rectification of the bias in the wavelet power spectrum . J. Atmos. Oceanic Technol. , 24 , 2093 – 2102 , . 10.1175/2007JTECHO511.1 Lott , F. , and H. Teitelbaum , 1993a : Linear unsteady mountain waves

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