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Christian Franzke, Andrew J. Majda, and Grant Branstator

planetary wave dynamics? In this linear view the atmospheric flow would consist of preferred flow patterns; any linear combination of these preferred patterns would again be a preferred flow pattern, and the probability density functions (PDFs) of these flow patterns would not have multiple extrema. If driven by additive white noise, these PDFs would be Gaussian. Another indication of linear dynamics is the form of mean tendencies in phase space. For a stable linear system these tendencies must be

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Lorenzo Tomassini

waves ( Riehl 1945 ). Riehl’s influential book on tropical meteorology ( Riehl 1954 ) summarized his insights into the interaction between moist convection and the atmospheric circulation in the tropics at that time. Riehl’s book is cited in Charney (1963) , and tropical depressions like those resulting from easterly waves were considered to be a model for the tropical circulation as a whole. Charney and Eliassen (1964) proposed a theory of the interaction between moist convection and the

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Amanda K. O’Rourke and Geoffrey K. Vallis

meridionally separate, but interdependent, eddy-driven and subtropical jets from the perspective of the generation, propagation, and breaking of atmospheric waves. Observations of an upper-tropospheric splitting of the zonal-mean zonal wind into an eddy-driven and subtropical jet occur in both the Northern Hemisphere ( Bordi et al. 2007 ) and the Southern Hemisphere ( Williams et al. 2007 ) winters. In the zonally asymmetric climatology, splitting of the subtropical and eddy-driven jets occurs often in

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Qingfang Jiang and James D. Doyle

1. Introduction Nearly all mountain-wave theories to date assume free-slip boundary conditions at the surface because the turbulent boundary layer is considered analytically intractable. Over the past two decades, the impact of the atmospheric boundary layer (BL) on mountain waves and wave breaking has been examined in a number of numerical model–based studies. Richard et al. (1989) studied four Boulder, Colorado, downslope windstorms using a numerical model with bottom friction, and found

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Xin Tan, Ming Bao, Dennis L. Hartmann, and Paulo Ceppi

eastern Pacific on Rossby wave breaking and atmospheric circulation in the NA. Other studies suggested a connection between the NP low-frequency flow and the NAO. Feldstein (2003) observed that for the positive NAO phase, an anomalous low-frequency wave train propagates across the NP to the east coast of North America 4 days prior to the onset of the NAO. Observations showed the existence of a linkage between the PNA and the NAO ( Pozo-Vázquez et al. 2001 ; Song et al. 2009 ; Pinto et al. 2011

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Nedjeljka Žagar, Damjan Jelić, Marten Blaauw, and Peter Bechtold

1. Introduction The majority of atmospheric energy is in the zonal-mean state. The distribution of the remaining energy as a function of the horizontal scale—the wave energy spectrum—is one of the fundamental characteristics of atmospheric dynamics. The energy spectrum is usually represented as a function of the dimensional horizontal wavenumber and it is characterized by a steeper-sloped region at the scales of baroclinic systems in between the two shallower-sloped regions at the global scales

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Hyodae Seo, Markus Jochum, Raghu Murtugudde, Arthur J. Miller, and John O. Roads

associated with the baroclinic interaction of these potential temperature and potential vorticity gradients is conducive to the generation of synoptic-scale weather disturbances called African easterly waves (AEWs; Rennick 1976 ; Reed et al. 1977 ). Hsieh and Cook (2005) also have pointed out the importance of cumulus convection and the associated release of latent heat within the ITCZ over the African continent in the generation of these atmospheric disturbances. The early analyses of AEWs have

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Eric D. Skyllingstad

VOL. 48, NO. 14 JOURNAL OF THE ATMOSPHERIC SCIENCES 15JULYI991Critical Layer Effects on Atmospheric Solitary and Cnoidal Waves ERIC D, SKYLLINGSTADPacific Northwest Laboratory, Richland, Washington(Manuscript received 29 January 1990, in final form 18 December 1990)ABSTRACT The interactions of atmospheric cnoidal waves with a critical level are examined using a two-dimensionalnumerical model. A cnoidal wave system is generated by applying

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Patrick T. Haertel, George N. Kiladis, Andrew Denno, and Thomas M. Rickenbach

the modes are separable in the lower portion (below 100 hPa) of an atmosphere with a very high upper boundary (6.25 hPa), which allows vertical wave propagation above 100 hPa as does the real atmosphere. We project a simulation of the atmospheric response to a transient heating onto the vertical structure functions depicted in Fig. 2 . The point of this exercise is to see if vertical-mode projections for a bounded atmosphere can be used to separate heating and circulations in the lower portion of

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Yue Wu, Stefan G. Llewellyn Smith, James W. Rottman, Dave Broutman, and Jean-Bernard H. Minster

density and total electron content (TEC; the total number of electrons present along a path between a transmitter and receiver) and can be detected by the ionospheric sounding techniques using, for example, the global positioning system (GPS). Thus, as first suggested in Peltier and Hines (1976) , information carried by atmospheric waves could give tsunami alerts, and this response takes from about 20 min to a few hours [see, e.g., Fig. 3 of Occhipinti et al. (2008) and Fig. 8 of Occhipinti et al

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