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Yukari Sumi and Hirohiko Masunaga

center of WIG wave is detected by utilizing a longitude–time cross section of filtered TBB data. First, zonal local minima of filtered TBB are searched at each time. Only a minimum locating at the center of a search area of ±10° is picked up, ignoring noisy fluctuations. All local minima are searched by moving the search area in zonal direction. Next, the minima colder than minus two standard deviations σ are defined as the longitudinal location of convective centers of WIG waves (WIG peaks). This

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Ali Asaadi, Gilbert Brunet, and M. K. Yau

average basic state. At days +4 to +5, the jet maximum weakens, a feature consistent with the onset of nonlinear processes to be discussed in Part II . It should be pointed out that the composite may not show the characteristics of a particular case, because of the slight latitudinal and/or longitudinal shift in the fields, differences in geographical location of the disturbances, and variations in phase speeds of the systems within the different lags (days 0 to +5). DMW09 reported that the

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Manuela Lehner, Richard Rotunno, and C. David Whiteman

1. Introduction Downslope windstorms occur throughout the world in the lee of large mountain ranges as synoptic winds perpendicular to the mountain flow over the barrier and descend and accelerate in the lee, where the resulting wind speeds can reach damaging magnitudes. Downslope windstorms have been studied in many high-mountain locations, including the Wasatch Mountains in Utah ( Lawson and Horel 2015 ), the Sierra Nevada ( Mayr and Armi 2010 ), the European Alps ( Richner and Hächler 2012

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Hanin Binder, Maxi Boettcher, Hanna Joos, and Heini Wernli

during the early phase of the WCB ascent, and its influence on the associated cyclone. Very little is known about the location of strongest WCB-related ascent and PV production relative to the cyclone center and whether these positive PV anomalies contribute to cyclone intensification. In addition, no studies are available on the relative importance of the W1 and W2 types of WCBs for cyclone development. d. Objectives and structure of this study The goal of this study is to quantify the role of WCBs

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H. Reed Ogrosky and Samuel N. Stechmann

. Other techniques for wave identification have also been used, of which a small sampling is discussed here. A spatial projection technique that made use of spherical harmonics at a single pressure level was used by Madden (2007) to identify free large-scale Rossby waves in the upper troposphere. Matthews and Madden (2000) used Fourier analysis of sea level pressure at nine locations in the tropics to study the 33-h barotropic Kelvin wave; see Salby (1984) for a discussion of earlier

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Kathleen A. Schiro, J. David Neelin, David K. Adams, and Benjamin R. Lintner

vertical profiles of key thermodynamic quantities and plume buoyancies computed using turbulent mixing to the observed onset of deep convection. 2. Data A suite of observations is used to establish relationships between CWV and deep convection across various instruments, time periods, and tropical locations. The principal location examined is the DOE ARM Mobile Facility at Manacapuru, Brazil (3°12′S, 60°35′W; 50-m altitude), established as part of the GOAmazon field campaign (January 2014–December 2015

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Gan Zhang, Zhuo Wang, Timothy J. Dunkerton, Melinda S. Peng, and Gudrun Magnusdottir

). We then search the circumpolar contours for the PV contour that crosses a meridian more than once, which is denoted as the PV overturning. The detected overturning is counted as one RWB incidence, and the location and zonal extent of the breaking bay (the equatorward tongue of high-PV air) is extracted. To investigate the spatial distribution of RWB, we locate the RWB centroids and count the frequency of RWB occurrence on a 5° × 5° resolution grid mesh. 3. Overview of the environmental conditions

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Shoichi Shige and Christian D. Kummerow

, strong cold-rain processes dominate and the orographic–nonorographic rainfall classification scheme was switched off in the GSMaP MWR algorithm. Fig . 2. Location of mesoscale mountain ranges of (top) the South Asian monsoon region (Western Ghats, Arakan Yoma, Bilauktaung, Cardamom, Annam Range, and the Philippines) and (bottom) Mexico. Of these six mountain ranges, only the Philippines belongs to the western North Pacific summer monsoon region, where continental influences are less significant; the

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Isabelle Prestel and Volkmar Wirth

suitable for our purposes. Note that the amount of surface friction can slightly modify the exact location of the transitions between the regimes (cf. Doyle and Durran 2002 ). To quantify the related sensitivity we carried out the same set of simulations with c d = 0.001 instead of 0.01. The result is shown in Fig. 6 . Overall, the regime behavior is unchanged with leeside separation, no separation, and postwave separation all being present quite like in the previous simulations. At the same time

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Alex O. Gonzalez, Christopher J. Slocum, Richard K. Taft, and Wayne H. Schubert

an important role near narrow boundary layer convergence regions, as seen in their Fig. 5. In this paper, we explore the roles of horizontal advection and horizontal diffusion in determining the location of the Ekman pumping. As global models increase their horizontal resolution, nonlinear dynamical effects, such as horizontal advection, may become more important. Also, such nonlinear dynamical effects may have significant consequences for the thermodynamical fields. Therefore, although we

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