doi:10.1007/s00376-016-5292-y

Charron M., E. Manzini, 2002: Gravity waves from fronts: Parameterization and middle atmosphere response in a general circulation model. J. Atmos. Sci., 59, 923- 941.f5561b475deb86087b363e46dae4174f

http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2002JAtS...59..923C%26db_key%3DPHY%26link_type%3DABSTRACT

http://xueshu.baidu.com/s?wd=paperuri%3A%2870568d12ecc8aa978e2f14c3e15cf285%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2002JAtS...59..923C%26db_key%3DPHY%26link_type%3DABSTRACT&ie=utf-8&sc_us=14892897854640456414

Davis C. A., K. A. Emanuel, 1991: Potential vorticity diagnostics of cyclogenesis. Mon. Wea. Rev., 119, 1929- 1953.10.1175/1520-0493(1991)1192.0.CO;2

00099b6ff956347d2a7f32b5053c3b73

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1991MWRv..119.1929D

http://adsabs.harvard.edu/abs/1991MWRv..119.1929DNot Available

Ford R., M. E. McIntyre, and W. A. Norton, 2000: Balance and the slow quasimanifold: Some explicit results. J. Atmos. Sci., 57, 1236- 1254.10.1175/1520-0469(2000)0572.0.CO;2

18e47fbe85171f98ce3bd01e1711ae2d

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2000JAtS...57.1236F

http://adsabs.harvard.edu/abs/2000JAtS...57.1236FThe ultimate limitations of the balance, slow-manifold, and potential vorticity inversion concepts are investigated. These limitations are associated with the weak but nonvanishing spontaneous-adjustment emission, or Lighthill radiation, of inertia–gravity waves by unsteady, two-dimensional or layerwise-two-dimensional vortical flow (the wave emission mechanism sometimes being called “geostrophic” adjustment even though it need not take the flow toward geostrophic balance). Spontaneous-adjustment emission is studied in detail for the case of unbounded -plane shallow-water flow, in which the potential vorticity anomalies are confined to a finite-sized region, but whose distribution within the region is otherwise completely general. The approach assumes that the Froude number and Rossby number satisfy 61 1 and 68 1 (implying, incidentally, that any balance would have to include gradient wind and other ageostrophic contributions). The method of matched asymptotic expansions is used to obtain a general mathematical description of spontaneous-adjustment emission in this parameter regime. Expansions are carried out to (), which is a high enough order to describe not only the weakly emitted waves but also, explicitly, the correspondingly weak radiation reaction upon the vortical flow, accounting for the loss of vortical energy. Exact evolution on a slow manifold, in its usual strict sense, would be incompatible with the arrow of time introduced by this radiation reaction and energy loss. The magnitude () of the radiation reaction may thus be taken to measure the degree of “fuzziness” of the entity that must exist in place of the strict slow manifold. That entity must, presumably, be not a simple invariant manifold, but rather an ()-thin, multileaved, fractal “stochastic layer” like those known for analogous but low-order coupled oscillator systems. It could more appropriately be called the “slow quasimanifold.”

Ford R., M. E. McIntyre, and W. A. Norton, 2002: Reply. J. Atmos.Sci., 59, 2878- 2882.0a7f0f25-cc5e-4275-8813-0212c889c064

f8d4d92b16eb064e8a8ae5d4c1d5e2b0

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refpaperuri:(62ea008bf1b56f0d518c0ac9a997648d)

http://xueshu.baidu.com/s?wd=paperuri%3A%2862ea008bf1b56f0d518c0ac9a997648d%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fonlinelibrary.wiley.com%2FsaveContent%3Fdoi%3D10.1002%252Fart.23522%26originUrl%3D%252Fdoi%252F10.1002%252Fart.23522%252Ffull&ie=utf-8&sc_us=17827728553259857216

Ford R., 1994a: Gravity wave radiation from vortex trains in rotating shallow water. J. Fluid Mech., 281, 81- 118.10.1017/S0022112094003046

604eed5341b295d6884ae7289bca4358

http%3A%2F%2Fjournals.cambridge.org%2Fabstract_S0022112094003046

http://journals.cambridge.org/abstract_S0022112094003046Not Available

Ford R., 1994b: The response of a rotating ellipse of uniform potential vorticity to gravity wave radiation. Physics of Fluids, 6, 3694- 3704.10.1063/1.868360

22823753

a80cc1e1d620405a09216e9e3d505e4c

http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2011WR011222%2Fpdf

http://onlinelibrary.wiley.com/doi/10.1029/2011WR011222/pdfKirchhoff incompressible rotating elliptical vortexsolution is extended to the case of weak compressibility in the rotating flane shallow water equations by means of matched asymptotic expansion, using the small Froude number F as the expansion parameter. The analysis shows that there is a correction to the shape of the rotating configuration at O(F 2), and a gradual elongation of the shape on a time scale F 4 t. When the aspect ratio of the ellipse is 4.6:1, the O(F 2) perturbation to its boundary shape becomes secular, and the vortex exhibits a tendency to pinch in the middle, breaking into two separate vortices. This behavior is consistent with the weakly nonlinear analysis of Williams (Ph.D. thesis, University of Leeds, 1992), and the numerical work of Chan et al. [J. Fluid Mech. 253, 173 (1993)], for the formally equivalent problem in a twoimensional compressible gas. When the Coriolis parameter is sufficiently large, the elongation of the ellipse may equilibrate before it reaches an aspect ratio of 4.6:1. The nature of the approach of the ellipse to its equilibrium aspect ratio is discussed in these cases, highlighting an asymmetry between cyclonic and anticyclonic vortices.

Fritts D. C., M. J. Alexander, 2003: Gravity wave dynamics and effects in the middle atmosphere. Rev. Geophys. , 41,1003, doi:10.1029/2001RG000106.10.1029/2012RG000409

884e5e7b5df148018377f209b2861976

http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2001RG000106%2Fabstract

http://onlinelibrary.wiley.com/doi/10.1029/2001RG000106/abstractAtmospheric gravity waves have been a subject of intense research activity in recent years because of their myriad effects and their major contributions to atmospheric circulation, structure, and variability. Apart from occasionally strong lower-atmospheric effects, the major wave influences occur in the middle atmosphere, between 10 and 110 km altitudes because of decreasing density and increasing wave amplitudes with altitude. Theoretical, numerical, and observational studies have advanced our understanding of gravity waves on many fronts since the review by [1984a]; the present review will focus on these more recent contributions. Progress includes a better appreciation of gravity wave sources and characteristics, the evolution of the gravity wave spectrum with altitude and with variations of wind and stability, the character and implications of observed climatologies, and the wave interaction and instability processes that constrain wave amplitudes and spectral shape. Recent studies have also expanded dramatically our understanding of gravity wave influences on the large-scale circulation and the thermal and constituent structures of the middle atmosphere. These advances have led to a number of parameterizations of gravity wave effects which are enabling ever more realistic descriptions of gravity wave forcing in large-scale models. There remain, nevertheless, a number of areas in which further progress is needed in refining our understanding of and our ability to describe and predict gravity wave influences in the middle atmosphere. Our view of these unknowns and needs is also offered.

Gent P. R., J. C. McWilliams, 1982: Intermediate model solutions to the Lorenz equations: Strange attractors and other phenomena. J. Atmos. Sci., 39, 3- 13.10.1175/1520-0469(1982)0392.0.CO;2

18d9928f-8c64-47b7-8c76-adcc005b8cc5

c011cdf3bab7d0bbeed6c9cd318981c8

http%3A%2F%2Fwww.ams.org%2Fmathscinet-getitem%3Fmr%3D848808

refpaperuri:(73c6d17c8aacd8a22d9cc75f5bb59994)

http://www.ams.org/mathscinet-getitem?mr=848808The equations which we are going to study in these notes were first presented in 1963 by E. N. Lorenz. They define a three-dimensional system of ordinary differential equations that depends on three real positive parameters. As we vary the parameters, we change the behaviour of the flow determined by the equations. For some parameter values, numerically computed solutions of the equations oscillate, apparently forever, in the pseudo-random way we now call "chaotic"; this is the main reason for the immense amount of interest generated by the equations in the eighteen years since Lorenz first presented them. In addition, there are some parameter values for which we see "preturbulence", a phenomenon in which trajectories oscillate chaotically for long periods of time before finally settling down to stable stationary or stable periodic behaviour, others in which we see "intermittent chaos", where trajectories alternate be tween chaotic and apparently stable periodic behaviours, and yet others in which we see "noisy periodicity", where trajectories appear chaotic though they stay very close to a non-stable periodic orbit. Though the Lorenz equations were not much studied in the years be tween 1963 and 1975, the number of man, woman, and computer hours spent on them in recent years - since they came to the general attention of mathematicians and other researchers - must be truly immense.

Gill A. E., 1982: Atmosphere-Ocean Dynamics. Academic Press,662 pp.35337ad8bf29810a12d899a1da4ef20e

http%3A%2F%2Fcore.ac.uk%2Fdisplay%2F21148477

http://core.ac.uk/display/21148477

Griffiths M., M. J. Reeder, 1996: Stratospheric inertia-gravity waves generated in a numerical model of frontogenesis. I: Model solutions. Quart. J. Roy. Meteor. Soc.,122, 1153-1174, doi: 10.1002/qj.49712253307.10.1002/qj.49712253307

debeaabd1a7f3b8416d3aafddfe8554b

http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2Fqj.49712253307%2Fpdf

http://onlinelibrary.wiley.com/doi/10.1002/qj.49712253307/pdfNot Available

Kim Y.-J., S. D. Eckermann, and H.-Y. Chun, 2003: An overview of the past, present and future of gravity-wave drag parameterization for numerical climate and weather prediction models. Atmos.-Ocean, 41, 65- 98.10.3137/ao.410105

8dd1e9b03b7abe3303a583f4b3bf6a56

http%3A%2F%2Fconnection.ebscohost.com%2Fc%2Farticles%2F19580555%2Foverview-past-present-future-gravity-wave-drag-parametrization-numerical-climate-weather-prediction-models

http://connection.ebscohost.com/c/articles/19580555/overview-past-present-future-gravity-wave-drag-parametrization-numerical-climate-weather-prediction-modelsAn overview of the parametrization of gravity wave drag in numerical weather prediction and climate simulation models is presented. The focus is primarily on understanding the current status of gravity wave drag parametrization as a step towards the new parametrizations that will be needed for the next generation of atmospheric models. Both the early history and latest developments in the field are discussed. Parametrizations developed specifically for orographic and convective sources of gravity waves are described separately, as are newer parametrizations that collectively treat a spectrum of gravity wave motions. The differences in issues in and approaches for the parametrization of the lower and upper atmospheres are highlighted. Various emerging issues are also discussed, such as explicitly resolved gravity waves and gravity wave drag in models, and a range of unparametrized gravity wave processes that may need attention for the next generation of gravity wave drag parametrizations in models.

Koch S. E., P. B. Dorian, 1988: A mesoscale gravity wave event observed during CCOPE. Part III: Wave environment and probable source mechanisms. Mon. Wea. Rev., 116, 2570- 2592.10.1175/1520-0493(1988)1162.0.CO;2

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a785a657220369e4c0f175a940ad2b85

http%3A%2F%2Fwww.researchgate.net%2Fpublication%2F24160608_A_mesoscale_gravity_wave_event_observed_during_CCOPE._II_-_Interactions_between_mesoscale_convective_systems_and_the_antecedent_waves

refpaperuri:(7b6d93490236d5d1a0841ff43217914b)

http://www.researchgate.net/publication/24160608_A_mesoscale_gravity_wave_event_observed_during_CCOPE._II_-_Interactions_between_mesoscale_convective_systems_and_the_antecedent_wavesAbstract This paper presents the results of a very detailed investigation into the effects of preexisting gravity waves upon convective systems, as well as the feedback effects of convection of varying intensity upon the waves. The analysis is based on the synthesis of synoptic surface and barograph data with high-resolution surface mesonetwork, radar, and satellite data collected during a gravity wave event described by Koch and Golus in Part I of this series of papers. Use is also made of the synoptic barograph data and satellite imagery to trace the waves beyond the mesonetwork and thus determine their apparent source region just upstream of the mesonetwork. It is shown that two of the gravity waves modulated convection within a weak squall line as they propagated across the line. The other six waves remained closely linked with convective systems that they appeared to trigger. However, it is shown that the waves were not excited by convection. Furthermore, the waves retained their signatures in the surface mesonetwork fields in the presence of rainshowers. Two episodes of strongest gravity wave activity are identified, each of which consisted of a packet of four wave troughs and ridges displaying wavelengths of 150 km. A Mesoscale Convective Complex (MCC) forms rapidly from very strong or severe thunderstorms apparently triggered by the individual members of the second wave packet. It is suggested that the large size and long duration of this complex were due in part to the periodic renewal and organization provided by this wave packet. Strong convection appears to substantially affect the gravity waves locally by augmenting the wave amplitude, reducing its wavelength, distorting the wave shape, altering the wave phase velocity, and greatly weakening the in-phase covariance between the perturbation wind and pressure ( p u *) fields. These convective effects upon the gravity waves are explained in terms of hydrostatic and nonhydrostatic pressure forces and gust front processes associated with thunderstorms. Despite the implication from these findings of the loss or obscuration of the original wave signal, the gravity wave signal remained intact just outside of the active storm cores and the entire wave-storm system exhibited outstanding spatial coherence over hundreds of kilometers. The observations are also compared to the predictions from wave-CISK theory. Although qualitative agreement is found, quantitative comparisons give rather unimpressive agreement, due in large measure to simplifications inherent to the theory.

Koch S. E., F. Q. Zhang, M. L. Kaplan, Y.-L. Lin, R. Weglarz, and C. M. Trexler, 2001: Numerical simulations of a gravity wave event over CCOPE. Part III: The role of a mountain-plains solenoid in the generation of the second wave episode. Mon. Wea. Rev., 129, 909- 932.4730aa3c6c9bf3e73996b074d3150cb6

http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2001MWRv..129..909K%26db_key%3DPHY%26link_type%3DEJOURNAL

http://xueshu.baidu.com/s?wd=paperuri%3A%280734cae56e07fc8ca380261681e5bf0d%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2001MWRv..129..909K%26db_key%3DPHY%26link_type%3DEJOURNAL&ie=utf-8&sc_us=9702560638543438940

Lac C., J.-P. Lafore, and J.-L. Redelsperger, 2002: Role of gravity waves in triggering deep convection during TOGA COARE. J. Atmos. Sci., 59, 1293- 1316.10.1175/1520-0469(2002)0592.0.CO;2

f6feaf3aba6d46032e77b2f440f98d6f

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2002JAtS...59.1293L

http://adsabs.harvard.edu/abs/2002JAtS...59.1293LAbstract The role of gravity waves in the initiation of convection over oceanic regions during the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE) experiment is investigated. First, an autocorrelation method is applied to infrared temperature observations of convective events from satellite images. It reveals that new deep convective cells often occur a few hours after a previous intense event at a typical distance of a few hundred kilometers. Such fast moving modes (faster than 15 m s611) are interpreted as the trace of gravity waves excited by previous convection and contributing to trigger further convection. Second, the specific case of 11–12 December 1992, during which an active squall line is generated after the collapse of a previous mesoscale convective system (MCS) nearby, is analyzed with a nonhydrostatic model. The triggering of the second MCS is well reproduced explicitly, owing to the use of the two-way interactive grid nesting. The convective source ...

Lindzen R. S., 1974: Wave-CISK in the tropics. J. Atmos. Sci., 31, 156- 179.10.1175/1520-0469(1974)0312.0.CO;2

ccdcb50482227462ef1ee6fba86168e3

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1974jats...31..156l

http://adsabs.harvard.edu/abs/1974jats...31..156lAbstract CISK (Conditional Instability of the Second Kind) is examined for internal waves where low-level convergence is due to the inviscid wave fields rather than to Ekman pumping. It is found that CISK-induced waves must give rise to mean cumulus activity (since there are no negative clouds), and it is suggested that this mean activity plays an important role in the finite-amplitude equilibration of the system. The most unstable CISK waves will be associated with very short vertical wavelengths [O(3 km)] in order to maximize (in some crude sense) subcloud convergence. Thus, the vertical scale is largely determined by the height of cloud base. The vertical scale, in turn, determines the dispersive relations between horizontal and temporal scales. It is found that there exists a wave-CISK mode which is independent of longitude, and hence independent of the mean zonal flow. Because of this independence, the period of this oscillation should form a prominent line in tropical spectra. This period turns out to be about 4.8 days which is indeed a prominent feature of tropical spectra. It is shown, due to longitudinal inhomogeneities in the tropics (such as land-sea), that the above oscillation must be accompanied by traveling disturbances whose period with respect to the ground will also be 4.8 days and whose longitudinal scales will typically be from 1000–3000 km depending on the mean zonal flow. It is further shown that the existence of the above oscillatory system has two additional implications: The above system is, itself, unstable with respect to gravity waves with horizontal scales on the order of 100–200 km. Such waves may be associated with cloud clusters. The above system leads to maximum low-level convergence (and hence, a tendency toward mean cumulus activity) in regions centered about ±6°–7° latitude, thus providing a possible explanation for the position of the ITCZ.

Liu L., L. K. Ran, and X. G. Sun, 2015: Analysis of the structure and propagation of a simulated squall line on 14 June 2009. Adv. Atmos. Sci.,32(4), 1049-1062, doi: 10.1007/s00376-014-4100-9.10.1007/s00376-014-4100-9

249bc87c17ab8eed65f09e4a497c76b8

http%3A%2F%2Fwww.cnki.com.cn%2FArticle%2FCJFDTOTAL-DQJZ201508003.htm

http://d.wanfangdata.com.cn/Periodical/dqkxjz-e201508003A squall line on 14 June 2009 in the provinces of Jiangsu and Anhui was well simulated using the Advanced Regional Prediction System (ARPS) model. Based on high resolution spatial and temporal data, a detailed analysis of the structural features and propagation mechanisms of the squall line was conducted. The dynamic and thermodynamic structural characteristics and their causes were analyzed in detail. Unbalanced flows were found to play a key role in initiating gravity waves during the squall line’s development. The spread and development of the gravity waves were sustained by convection in the wave-CISK process. The squall line’s propagation and development mainly relied on the combined effect of gravity waves at the midlevel and cold outflow along the gust front. New cells were continuously forced by the cold pool outflow and were enhanced and lifted by the intense upward motion. At a particular phase, the new cells merged with the updraft of the gravity waves, leading to an intense updraft that strengthened the squall line.

Oouchi K., 1999: Hierarchical organization of super cloud cluster caused by WISHE, convectively induced gravity waves and cold pool. J. Meteor. Soc.Japan, 77, 907- 927.10.1175/1520-0469(1999)056<2728:OTFSIT>2.0.CO;2

79141ac80697c328e4e16963bd6baa46

http%3A%2F%2Fci.nii.ac.jp%2Fnaid%2F10013463623

http://ci.nii.ac.jp/naid/10013463623To understand the mechanism of hierarchical organization of the tropical super cloud cluster and its eastward propagation, we performed numerical experiments using a 2D cumulus-scale resolving model (Yamasaki, 1984). In the experiments, synoptic-scale convection similar to super cloud cluster (SCC) developed with a reasonable eastward phase velocity of 3-6 m s

O'Sullivan, D., T. J. Dunkerton, 1995: Generation of inertia-gravity waves in a simulated life cycle of baroclinic instability. J. Atmos. Sci., 52, 3695- 3716.10.1175/1520-0469(1995)0522.0.CO;2

c1ad4e77dc448107fe94f1d31bea4b90

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1995JAtS...52.3695O

http://adsabs.harvard.edu/abs/1995JAtS...52.3695OThe excitation and propagation of inertia-gravity waves (IGWs) generated by an unstable baroclinic wave was examined with a high-resolution 3D nonlinear numerical model. IGWs arose spontaneously as the tropospheric jetstream was distorted by baroclinic instability and strong parcel accelerations took place, primarily in the jetstream exit region of the upper troposphere. Subsequent propagation of IGWs occurred in regions of strong windspeed-in the tropospheric and stratospheric jets, and in a cutoff low formed during the baroclinic lifecycle. IGWs on the flanks of these jets were rotated inward by differential advection and subsequently absorbed by the model's hyperdiffusion. Although absorption of IGWs at the sidewalls of the jet is an artifact of the model, IGW propagation was for the most pan confined to regions with an intrinsic period shorter than the local inertial period. Only a few IGWs were able to penetrate the middle stratosphere, due to weak winds or an unfavorable alignment of wavevector with respect to the mean flow.IGWs are important both as a synoptic signal in the jetstream, which may influence subsequent tropospheric developments, and as a source of isentropic or cross-isentropic mixing in the lower stratosphere. The authors' results demonstrated for the first time numerically a significant isentropic displacement of potential vorticity isopleths due to IGWs above the tropopause. Since conditions for IGW propagation are favorable within a jet, a region of strong isentropic potential vorticity gradient, it is likely that inertia-gravity waves affect the permeability of the lower stratospheric vortex and may in some instances lead to stratosphere-troposphere exchange.

Pand ya, R. E., D. R. Durran, M. L. Weisman, 2000: The influence of convective thermal forcing on the three-dimensional circulation around squall lines. J. Atmos. Sci., 57, 29- 45.d1490b3d563e63dc2f87f2acec48450c

http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2000JAtS...57...29P%26link_type%3DEJOURNAL%26db_key%3DPHY

http://xueshu.baidu.com/s?wd=paperuri%3A%2801abc4dfddcbf2c358b2b5aee8eb1297%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2000JAtS...57...29P%26link_type%3DEJOURNAL%26db_key%3DPHY&ie=utf-8&sc_us=13969511048250913279

Peng L., C.-H. Sui, K.-M. Lau, and W.-K. Tao, 2001: Genesis and evolution of hierarchical cloud clusters in a two-dimensional cumulus-resolving model. J. Atmos. Sci., 58, 877- 895.10.1175/1520-0469(2001)0582.0.CO;2

2e709ab5dedc5346dae890b967f82479

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2001JAtS...58..877P

http://adsabs.harvard.edu/abs/2001JAtS...58..877PA two-dimensional cloud ensemble model is integrated over a basin-scale domain with prescribed sea surface temperature (SST), to study the formation and evolution of cloud clusters over a large-scale warm pool. Neither a basic zonal flow is prescribed nor is a single perturbation initially given. The results show that deep convective clouds appear in hierarchical clustered patterns and are limited to the area of warm SST above 28C. The most fundamental cloud cluster in the model has a horizontal scale of a few hundred kilometers, in which new cumulus clouds are generated at the leading edge of a propagating surface cold-air pool--the gust front. It may last for days and propagate for a long distance if the background flow is broad and persistent as is the case in the low-level convergence zone of the SST-induced background flow, The largest hierarchical propagating cloud systems in the model have horizontal scales up to 3000 km and consist of up to four cloud clusters that are generally of gust front type. The constituent cloud clusters are generated intermittently and have life spans of 12-36 h. The internal heating of the constituent clusters collectively induces an overall troposphere-deep gravity wave. The overall wave travels in the direction of the tropospheric deep shear at a speed determined by the thermodynamic asymmetry in the wave created by the transition from warm and moist incoming air in the front to drier and cooler air in the rear The development of new cumulus clusters in the front region of the hierarchical system is due to the combined effect of the overall wave and the gravity waves excited by the constituent clusters on the lower-tropospheric stability. When there are no intertuptions from outside the cloud system, new cloud clusters developed intermittently from shallow disturbances hundreds of kilometers ahead of the existing deep convection. The resulting hierarchical cloud pattern resembles the observed equatorial super cloud cluster (SCC) in the time-longitude diagram However, the life spans of the constituent clusters of the system are shorter than that in the observed SCC.

Plougonven R., V. Zeitlin, 2002: Internal gravity wave emission from a pancake vortex: An example of wave-vortex interaction in strongly stratified flows. Physics of Fluids, 14, 1259- 1268.10.1063/1.1448297

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http%3A%2F%2Fscitation.aip.org%2Fcontent%2Faip%2Fjournal%2Fpof2%2F14%2F3%2F10.1063%2F1.1448297

http://scitation.aip.org/content/aip/journal/pof2/14/3/10.1063/1.1448297At small Froude numbers the motion of a stably stratified fluid consists of a quasisteady vortical component and a propagating wave component. The vortical component is organized into layers of horizontal motions with well-pronounced vertical vorticity and often takes the form of so-called ancakevortices. An analytical model of such a vortex that is a solution of the Euleroussinesq equations at a vanishing Froude number is constructed as a superposition of horizontal two-dimensional Kirchhoff elliptic vortices. This vortex is nonstationary and internal gravity waves are, therefore, excited by its motion. The radiation properties are studied by matching the vortex field with the far internal gravity wave field according to the procedure applied in acoustics to determine vortex sound. The structure of the gravity wave field is completely quantified. By calculating energy and angular momentum fluxes carried by outgoing waves and attributing them to the adiabatic change of the vortex parameters, we calculate the backreaction of the internal gravity waves radiation and show that, as in the case of acoustic radiation by the Kirchhoff vortex, this adiabatic evolution leads to an elongation of the vortex, and its eventual destabilization.

Plougonven R., H. Teitelbaum, 2003: Comparison of a large-scale inertia-gravity wave as seen in the ECMWF analyses and from radiosondes. Geophys. Res. Lett., 30, 1954.10.1029/2003GL017716

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2003GL017716%2Fcitedby

http://onlinelibrary.wiley.com/doi/10.1029/2003GL017716/citedbyThe location, characteristics and evolution of a large-scale inertia-gravity wave that occurred in the lower stratosphere over the North of the British Isles on February 6, 1997, are studied. Numerous high-resolution radiosondes were available at that time and in that region as part of the FASTEX database. They reveal an intense, large-scale inertia-gravity wave (IGW), propagating upwards above the tropopause. Maps of the divergence of the horizontal wind, on isentropic surfaces, were obtained from the ECMWF analyses, and showed a clear pattern of alternating bands of convergence and divergence, at the lower stratospheric heights, in the same geographical region and starting at the same time. The comparison of the characteristics of this IGW in the analyses and in the observations suggests that the ECMWF analyses can be used for qualitative indications regarding the locations most favorable to large-scale IGW generation and the corresponding orientation of the waves.

Plougonven R., F. Q. Zhang, 2007: On the forcing of inertia-gravity waves by synoptic-scale flows. J. Atmos. Sci., 64, 1737- 1742.10.1175/JAS3901.1

e7a5cd87814c5454ac8ba67229647c3f

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2007JAtS...64.1737P

http://adsabs.harvard.edu/abs/2007JAtS...64.1737PStudies on the spontaneous emission of gravity waves from jets, both observational and numerical, have emphasized that excitation of gravity waves occurred preferentially near regions of imbalance. Yet a quantitative relation between the several large-scale diagnostics of imbalance and the excited waves is still lacking. The purpose of the present note is to investigate one possible way to relate quantitatively the gravity waves to diagnostics of the large-scale flow that is exciting them. Scaling arguments are used to determine how the large-scale flow may provide a forcing on the right-hand side of a wave equation describing the linear dynamics of the excited waves. The residual of the nonlinear balance equation plays an important role in this forcing.

Plougonven R., H. Teitelbaum, and V. Zeitlin, 2003: Inertia gravity wave generation by the tropospheric midlatitude jet as given by the Fronts and Atlantic Storm-Track Experiment radio soundings. J. Geophys. Res., 108, 4686.10.1029/2003JD003535

7b06dae15d731759e729fe43fc0113db

http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2003JD003535%2Ffull

http://onlinelibrary.wiley.com/doi/10.1029/2003JD003535/fullGeneration of inertia gravity waves by the midlatitude tropospheric jet is studied on the basis of the data obtained from the radio soundings over the North Atlantic during the Fronts and Atlantic Storm-Track Experiment campaign. A sample of 224 radio soundings is used to analyze the wave activity as a function of the distance to the jet. It is shown that radio soundings displaying the most intense gravity wave activity, both in the stratosphere and in the troposphere, are the ones closest to the jet axis. Thus the jet region is the dominant source of gravity waves in this region far from orography. Further examination allows for identification of two specific regions of the flow that are associated with intense gravity wave activity: the vicinity of the maximum of the jet velocity and the regions of strong curvature of the jet. The detailed case studies we provide suggest that geostrophic adjustment is the dynamical mechanism responsible for the generation of large-amplitude inertia gravity waves in the regions of the strong curvature of the wind. The generation of waves in the vicinity of the regions where the wind veers, in the deep troughs of the geopotential, appears to be systematic.

Raymond D. J., 1987: A forced gravity wave model of serf-organizing convection. J. Atmos. Sci., 44, 3528- 3543.10.1175/1520-0469(1987)0442.0.CO;2

f752a443112fbfeeb8e42733ea6ef3dd

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1987JAtS...44.3528R

http://adsabs.harvard.edu/abs/1987JAtS...44.3528RA two-dimensional, hydrostatic, nonrotating numerical model with a cumulus paramelerizafion is developed to study the early stages of mesozcale convective systems. Amplifying, forced gravity waves occur when peneirative downdrafts are present. Updraft heating by itself is unable to cause convective sysiems to intensify. Propagation speeds are in rough agreement with those observed in midlatitude mesoscale convective systems. The conditionalityof the convection and the horizontal advection of precipitation by the relative wind produce las between lifting and convection that are not found in conventional wave-CISK models. These lags slow the growth and reduce the propasation speeds of forced gravity waves.

Reeder M. J., M. Griffiths, 1996: Stratospheric inertia-gravity waves generated in a numerical model of frontogenesis. Part II: Wave sources, generation mechanisms and momentum fluxes. Quart. J. Roy. Meteor. Soc., 122, 1175- 1195.10.1002/qj.49712253308

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2Fqj.49712253308%2Ffull

http://xueshu.baidu.com/s?wd=paperuri%3A%28231bc5e14aa3e296fe59938f75cf32ff%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2Fqj.49712253308%2Ffull&ie=utf-8&sc_us=16754151180006423479Not Available

Reznik G. M., V. Zeitlin, and M. Ben Jelloul, 2001: Nonlinear theory of geostrophic adjustment. Part I: Rotating shallow-water model. J. Fluid Mech., 445, 93- 120.10.1017/S002211200100550X

2fd324c58d7dd4d95c2e4cf5eb89c910

http%3A%2F%2Fwww.ams.org%2Fmathscinet-getitem%3Fmr%3D1875696

http://www.ams.org/mathscinet-getitem?mr=1875696We develop a theory of nonlinear geostrophic adjustment of arbitrary localized (i.e. finite-energy) disturbances in the framework of the non-dissipative rotating shallow-water dynamics. The only assumptions made are the well-defined scale of disturbance and the smallness of the Rossby number Ro. By systematically using the multi-time-scale perturbation expansions in Rossby number it is shown that the resulting field is split in a unique way into slow and fast components evolving with characteristic time scales f

Sato K., 1994: A statistical study of the structure, saturation and sources of inertio-gravity waves in the lower stratosphere observed with the MU radar. J. Atmos. Terr. Phys., 56, 755- 774.10.1016/0021-9169(94)90131-7

1eb9e8c6a363925db767e070bf5dce45

http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2F0021916994901317

http://www.sciencedirect.com/science/article/pii/0021916994901317Moreover, in order to examine the generation mechanisms of the IGWs, an analysis is made from two points of view: geostrophic adjustment of the westerly wind jet and the topographic effect. The meridional propagation direction of IGWs is examined in a section of latitude and altitude relative to the jet axis using ECMWF operational data. Most of the IGWs observed in the 12–18 km height region (above the ground) in winter propagate meridionally toward the jet axis, indicating that geostrophic adjustment at least just as the jet axis is not the main generation mechanism of the IGWs. On the other hand, the characteristics of intensive IGWs propagating westward relative to the background wind in the 18–22 km height region in winter are in good accord with mountain waves excited in strong westerly winds near the surface.

Saujani S., T. G. Shepherd, 2002: Comments on "Balance and the slow quasimanifold: Some explicit results". J. Atmos. Sci., 59, 2874- 2877.10.1175/1520-0469(2002)0592.0.CO;2

a7f7a75a6fadb6f64a704261af572454

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2002jats...59.2874s

http://adsabs.harvard.edu/abs/2002jats...59.2874sNot Available

Schmidt J. M., W. R. Cotton, 1990: Interactions between upper and lower tropospheric gravity waves on squall line structure and maintenance. J. Atmos. Sci., 47, 1205- 1222.10.1175/1520-0469(1990)047<1205:IBUALT>2.0.CO;2

46140e41a081419c973cb04a202affd9

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1990JAtS...47.1205S

http://adsabs.harvard.edu/abs/1990JAtS...47.1205SAbstract Using a simplified thermodynamic sounding, and variable vertical wind shear, we investigate the role of gravity waves on the structure and propagation of a simulated two-dimensional squall line. Based on an observed squall line environment, the modeled troposphere has been divided into three distinct thermodynamic layers. These consist of an absolutely stable atmospheric boundary layer (ABL), an elevated well-mixed layer, and an upper tropospheric layer of intermediate stability. We find the mixed layer to have a dual role; it has a reduced stability and thus provides abundant buoyancy for the convective scale updrafts, and it provides an ideal layer to trap meso-scale (20-200 km) wave energy generated in the stable layers. The generated waves thus have a significant and lasting impact on the simulation. We also find this thermodynamic structure to be conducive to both strong surface wind perturbations and long-lived squall lines. Experiments that vary the vertical wind shear profile demonstrate...

Smith R. B., 1979: The influence of mountains on the atmosphere. Advances in Geophysics, 21, 87- 230.698ce93fbbecc0a30c85fd103b73130c

http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS0065268708602629

http://www.sciencedirect.com/science/article/pii/S0065268708602629The chapter reviews the meteorological phenomena that are associated with topography. The study of airflow past mountains is complicated by the wide range of scales that must be considered. The ratios of the mountain width to each of the natural length scales are important in determining the physical regime of the flow. This idea is emphasized in the chapter by treating the effects of boundary layers and buoyancy. The theory of two-dimensional mountain waves with the help of its governing equations is presented and the observations of mountain waves are presented. The chapter also examines the influence of the boundary layer on mountain flows and slope winds and mountain and valley winds. It considers the perturbation to the wind flow caused by a mountain of intermediate scale where the rotation of the Earth cannot be neglected. For this the flow near mesoscale and synoptic-scale mountains, quasi-geostrophic flow over a mountain, the effect of inertia on the flow over mesoscale mountains, and theories of lee cyclogenesis are discussed. Finally the chapter describes planetary-scale mountain waves; a vertically integrated model of topographically forced planetary waves; the vertical structure of planetary waves; models of stationary planetary waves allowing meridional propagation and lateral; and variation in the background wind.

Snyder C., R. Plougonven, and D. J. Muraki, 2009: Mechanisms for spontaneous gravity wave generation within a dipole vortex. J. Atmos. Sci., 66, 3464- 3478.617bd3e13db87b5a6c7ffd6f96b697a3

http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2009JAtS...66.3464S%26db_key%3DPHY%26link_type%3DABSTRACT

http://xueshu.baidu.com/s?wd=paperuri%3A%28a63ce3bac10ff16fa6695fd6530ef12d%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2009JAtS...66.3464S%26db_key%3DPHY%26link_type%3DABSTRACT&ie=utf-8&sc_us=18073706775284077669

Song I.-S., H.-Y. Chun, and T. P. Lane, 2003: Generation mechanisms of convectively forced internal gravity waves and their propagation to the stratosphere. J. Atmos. Sci., 60, 1960- 1980.10.1175/1520-0469(2003)0602.0.CO;2

e207fcf69463a8001a73a2c8db5e69e5

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2003JAtS...60.1960S

http://adsabs.harvard.edu/abs/2003JAtS...60.1960SAbstract Characteristics of gravity waves induced by mesoscale convective storms and the gravity wave sources are investigated using a two-dimensional cloud-resolving numerical model. In a nonlinear moist (control) simulation, the convective system reaches a quasi-steady state after 4 h in which convective cells are periodically regenerated from a gust front updraft. In the convective storms, there are two types of wave forcing: nonlinear forcing in the form of the divergences of momentum and heat flux, and diabatic forcing. The magnitude of the nonlinear source is 2 to 3 times larger than the diabatic source, especially in the upper troposphere. Three quasi-linear dry simulations forced by the wave sources obtained from the control (CTL) simulation are performed to investigate characteristics of gravity waves induced by the various wave source mechanisms. In the three dry simulations, the magnitudes of the perturbations produced in the stratosphere are comparable, yet much larger than those in the CTL si...

Tulich S. N., B. E. Mapes, 2008: Multiscale convective wave disturbances in the tropics: Insights from a two-dimensional cloud-resolving model. J. Atmos. Sci., 65, 140- 155.10.1175/2007JAS2353.1

2875e6729e5cd6e1d11b21d7849ec2a3

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2008JAtS...65..140T

http://adsabs.harvard.edu/abs/2008JAtS...65..140TMultiscale convective wave disturbances with structures broadly resembling observed tropical waves are found to emerge spontaneously in a nonrotating, two-dimensional cloud model forced by uniform cooling. To articulate the dynamics of these waves, model outputs are objectively analyzed in a discrete truncated space consisting of three cloud types (shallow convective, deep convective, and stratiform) and three dynamical vertical wavelength bands. Model experiments confirm that diabatic processes in deep convective and stratiform regions are essential to the formation of multiscale convective wave patterns. Specifically, upper-level heating (together with low-level cooling) serves to preferentially excite discrete horizontally propagating wave packets with roughly a full-wavelength structure in troposphere and “dry” phase speeds in the range 16–18 m s. These wave packets enhance the triggering of new deep convective cloud systems, via low-level destabilization. The new convection in turn causes additional heating over cooling, through delayed development of high-based deep convective cells with persistent stratiform anvils. This delayed forcing leads to an intensification and then widening of the low-level cold phases of wave packets as they move through convecting regions. Additional widening occurs when slower-moving (658 m s)“gust front” wave packets excited by cooling just above the boundary layer trigger additional deep convection in the vicinity of earlier convection. Shallow convection, meanwhile, provides positive forcing that reduces convective wave speeds and destroys relatively small-amplitude-sized waves. Experiments with prescribed modal wind damping establish the critical role of short vertical wavelengths in setting the equivalent depth of the waves. However, damping of deep vertical wavelengths prevents the clustering of mesoscale convective wave disturbances into larger-scale envelopes, so these circulations are important as well.

Uccellini L. W., S. E. Koch, 1987: The synoptic setting and possible energy sources for mesoscale wave disturbances. Mon. Wea. Rev., 115, 721- 729.10.1175/1520-0493(1987)1152.0.CO;2

6d7aeebed53ba61e64c48dcdb8390eec

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1987MWRv..115..721U

http://adsabs.harvard.edu/abs/1987MWRv..115..721UNot Available

Wang S. G., F. Q. Zhang, 2007: Sensitivity of mesoscale gravity waves to the baroclinicity of jet-front systems. Mon. Wea. Rev., 135, 670- 688.10.1175/MWR3314.1

79dc5ef6d5dd48970f3cb778a1d5d21d

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2007MWRv..135..670W

http://adsabs.harvard.edu/abs/2007MWRv..135..670WThis study investigates the sensitivity of mesoscale gravity waves to the baroclinicity of the background jet-front systems by simulating different life cycles of baroclinic waves with a high-resolution mesoscale model. Four simulations are made starting from two-dimensional baroclinic jets having different static stability and wind shear in order to obtain baroclinic waves with significantly different growth rates. In all experiments, vertically propagating mesoscale gravity waves are simulated in the exit region of upper-tropospheric jet streaks. A two-dimensional spectral analysis demonstrates that these gravity waves have multiple components with different wave characteristics. The short-scale wave components that are preserved by a high-pass filter with a cutoff wavelength of 200 km have horizontal wavelengths of 8509“161 km and intrinsic frequencies of 309“11 times the Coriolis parameter. The medium-scale waves that are preserved by a bandpass filter (with 200- and 600-km cutoff wavelengths) have horizontal wavelengths of 25009“350 km and intrinsic frequencies less than 3 times the Coriolis parameter. The intrinsic frequencies of these gravity waves tend to increase with the growth rate of the baroclinic waves; gravity waves with similar frequency are found in the experiments with similar average baroclinic wave growth rate but with significantly different initial tropospheric static stability and tropopause geometry. The residuals of the nonlinear balance equation are used to assess the flow imbalance. In all experiments, the developing background baroclinic waves evolve from an initially balanced state to the strongly unbalanced state especially near the exit region of upper-level jet fronts before mature mesoscale gravity waves are generated. It is found that the growth rate of flow imbalance also correlates well to the growth rate of baroclinic waves and thus correlates to the frequency of gravity waves.

Wang S. G., F. Q. Zhang, and C. Snyder, 2009: Generation and propagation of inertia-gravity waves from vortex dipoles and jets. J. Atmos. Sci., 66, 1294- 1314.47c5699beed5c176da47bb520953435f

http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2009JAtS...66.1294W%26db_key%3DPHY%26link_type%3DABSTRACT

http://xueshu.baidu.com/s?wd=paperuri%3A%28adb62d48ba9022bb732ecddcfce650f0%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2009JAtS...66.1294W%26db_key%3DPHY%26link_type%3DABSTRACT&ie=utf-8&sc_us=4149392687355533698

Wang S. G., F. Q. Zhang, 2010: Source of gravity waves within a vortex-dipole jet revealed by a linear model. J. Atmos. Sci., 67, 1438- 1455.cebf99e3aaa837cb843bdda75e2ed263

http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2010JAtS...67.1438W%26db_key%3DPHY%26link_type%3DABSTRACT

http://xueshu.baidu.com/s?wd=paperuri%3A%2886af6297ead7775cfa67f1e1739ed4a4%29&filter=sc_long_sign&tn=SE_xueshusource_2kduw22v&sc_vurl=http%3A%2F%2Fadsabs.harvard.edu%2Fcgi-bin%2Fnph-data_query%3Fbibcode%3D2010JAtS...67.1438W%26db_key%3DPHY%26link_type%3DABSTRACT&ie=utf-8&sc_us=16662374317739811712

Wang S. G., F. Q. Zhang, and C. C. Epifanio, 2010: Forced gravity wave response near the jet exit region in a linear model. Quart. J. Roy. Meteor. Soc., 136, 1773- 1787.10.1002/qj.676

09a379dedc1664e1f04a073abc86b9dd

http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2Fqj.676%2Fabstract

http://onlinelibrary.wiley.com/doi/10.1002/qj.676/abstractAbstract This study investigates the propagation of gravity waves in the region of significant horizontal and vertical shear associated with a localized atmospheric jet using a linear model. Gravity waves are produced in the linear model by imposing prescribed divergence/convergence forcing of various scales near the core of an idealized local jet. The spatial structures of these forced gravity waves are nearly steady after a few inertial periods, despite the amplitudes slowly increasing with time. Linear model simulated wave response to prescribed forcing shows limited dependence on the scales of the forcing. It is found that the wave structure (e.g. horizontal/vertical wavelengths, phases and locations) away from the forcing are largely constrained by the environmental wind shear through the wave capture mechanism. Consequently, simulated gravity wave activities have the tendency to be focused on the vicinity where the line of constant shear aspect ratio approximates to the characteristic large-scale environmental aspect ratio ( f/N ). Ray tracing analysis is further used to demonstrate that wave capturing is the consequence of different influences of the horizontal and vertical shears upon longer and shorter waves. Copyright 2010 Royal Meteorological Society

Williams P. D., T. W. N. Haine, and P. L. Read, 2005: On the generation mechanisms of short-scale unbalanced modes in rotating two-layer flows with vertical shear. J. Fluid Mech., 528, 1- 22.10.1017/S0022112004002873

ed765860343bf6123ebf30c536bfbeee

http%3A%2F%2Fjournals.cambridge.org%2Fabstract_S0022112004002873

http://journals.cambridge.org/abstract_S0022112004002873We report on the results of a laboratory investigation using a rotating two-layer annulus experiment, which exhibits both large-scale vortical modes and short-scale divergent modes. A sophisticated visualization method allows us to observe the flow at very high spatial and temporal resolution. The balanced long-wavelength modes appear only when the Froude number is supercritical (i.e. F > F upi^2/2), and are therefore consistent with generation by a baroclinic instability. The unbalanced short-wavelength modes appear locally in every single baroclinically unstable flow, providing perhaps the first direct experimental evidence that all evolving vortical flows will tend to emit freely propagating inertia-gravity waves. The short-wavelength modes also appear in certain baroclinically stable flows.

Wu D. L., F. Q. Zhang, 2004: A study of mesoscale gravity waves over the North Atlantic with satellite observations and a mesoscale model. J. Geophys. Res., 109, D22104.10.1029/2004JD005090

f8ff7430dcfbccd2fbf4867b2c990c19

http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2004JD005090%2Fcitedby

http://onlinelibrary.wiley.com/doi/10.1029/2004JD005090/citedbySatellite microwave data are used to study gravity wave properties and variabilities over the northeastern United States and the North Atlantic in the December-January periods. The gravity waves in this region, found in many winters, can reach the stratopause with growing amplitude. The Advanced Microwave Sounding Unit-A (AMSU-A) observations show that the wave occurrences are correlated well with the intensity and location of the tropospheric baroclinic jet front systems. To further investigate the cause(s) and properties of the North Atlantic gravity waves, we focus on a series of wave events during 19-21 January 2003 and compare AMSU-A observations to simulations from a mesoscale model (MM5). The simulated gravity waves compare qualitatively well with the satellite observations in terms of wave structures, timing, and overall morphology. Excitation mechanisms of these large-amplitude waves in the troposphere are complex and subject to further investigations.

Xue, M., Coauthors, 2001: The Advanced Regional Prediction System (ARPS) multi-scale nonhydrostatic atmospheric simulation and prediction tool. Part II: Model physics and applications. Meteor. Atmos. Phys., 76, 143- 165.

Zhang F. Q., 2004: Generation of mesoscale gravity waves in upper-tropospheric jet-front systems. J. Atmos. Sci., 61, 440- 457.10.1175/1520-0469(2004)061<0440:GOMGWI>2.0.CO;2

d0b9c8c6ef5abe2b9eca30ba56d6bacb

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F2004JAtS...61..440Z

http://adsabs.harvard.edu/abs/2004JAtS...61..440ZMultiply nested mesoscale numerical simulations with horizontal resolution up to 3.3 km are performed to study the generation of mesoscale gravity waves during the life cycle of idealized baroclinic jet–front systems. Long-lived vertically propagating mesoscale gravity waves with horizontal wavelengths 65100–200 km are simulated originating from the exit region of the upper-tropospheric jet streak, in a manner consistent with past observational studies. The residual of the nonlinear balance equation is found to be a useful index in diagnosing flow imbalance and predicting wave generation. The imbalance diagnosis and model simulations suggest that balance adjustment, as a generalization of geostrophic adjustment, is likely responsible for generating these mesoscale gravity waves. It is hypothesized that, through balance adjustment, the continuous generation of flow imbalance from the developing baroclinic wave will lead to the continuous radiation of gravity waves.

Zhang F. Q., S. E. Koch, C. A. Davis, and M. L. Kaplan, 2000: A survey of unbalanced flow diagnostics and their application. Adv. Atmos. Sci.,17, 165-183, doi: 10.1007/s00376-000-0001-1.10.1007/s00376-000-0001-1

53cee607e99fc5546399877f99111df4

http%3A%2F%2Fwww.cnki.com.cn%2FArticle%2FCJFDTotal-DQJZ200002000.htm

http://www.cnki.com.cn/Article/CJFDTotal-DQJZ200002000.htm

Zhang F. Q., C. A. Davis, M. L. Kaplan, and S. E. Koch, 2001: Wavelet analysis and the governing dynamics of a large amplitude mesoscale gravity wave event along the east coast of the United States. Quart. J. Roy. Meteor. Soc., 127, 2209- 2245.10.1002/qj.49712757702

48860890877d19be9a8f84144de98f50

http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2Fqj.49712757702%2Fcitedby

http://onlinelibrary.wiley.com/doi/10.1002/qj.49712757702/citedbyNot Available