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Bianca Adler, C. David Whiteman, Sebastian W. Hoch, Manuela Lehner, and Norbert Kalthoff

ubiquitous in stable boundary layers (e.g., Viana et al. 2007 ). At the crater, gravity waves generated in the stable boundary layer over the surrounding plain or produced by airflow over the crater rim ( Fritts et al. 2010 ) could affect the pressure difference inside the crater as they crossed the crater, depending on their wavelength. To detect gravity waves on the plain, we applied a trend-removal technique to the surface pressure measured at SW. The resulting pressure oscillations had a maximum

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Todd D. Sikora, George S. Young, Hampton N. Shirer, and Rick D. Chapman

marine atmospheric boundary layer (MABL) can produce characteristic signatures in radar imagery via their momentum exchange with the ocean surface. RAR and SAR, therefore, are expected to be powerful sensors for studying the vast array of phenomena that inhabit the MABL. Preliminary confirmations of these expectations have been realized by Gerling (1986) , Thomson et al. (1992) , Alpers and Brümmer (1994) , and Mourad (1996) , among others. The motivation behind the current study arises from the

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Gandikota V. Rao

VOL. 9, NO. 1 JOURNAl. OF APPLIED METEOROLOGY FEBRUARY1970Preliminary Estimates of Energy Conversion in a Weak Disturbance in the Easterlies~ GANDIKOTA V. RAO~Meteorological Service of Canada, Toronto, Ontario(Manuscript received 7 January 1969, in revised form 22 September 1969)ABSTRACT The possible roles of the boundary flux of potential energy and the basic tropical easterly current in maintaining weak

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Larry Mahrt

. 1981 ; Hanna 1983 ; Etling 1990 ) or common sudden wind direction shifts ( Mahrt 2008 ). The physics of sudden wind direction changes is poorly understood, but candidate influences are briefly surveyed by Mahrt (2007b) . Contributions include steepening gravity waves, density currents, pulses of drainage flow, and numerous other more complex signatures. The inverse relationship of the wind direction variability to the mean wind speed has been generalized by Joffre and Laurila (1988) and Hanna

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P. Alpert, S. O. Krichak, T. N. Krishnamurti, U. Stein, and M. Tsidulko

, the initializationprocedures, and other model characteristics. The current experiments, however, provide a quantitative approach forestimating the relative roles of the aforementioned boundary factors in mesoscale developments with the aid of thePennsylvania State University-National Center for Atmospheric Research MM4 mesoscale model and The FloridaState University regional system.1. Introduction Mesoscale numerical simulations are well known tobe highly sensitive to boundary conditions

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C. H. Liu and D. Y. C. Leung

atmosphere is a function of mean wind, temperature, and turbulence field. Therefore, the governing mathematical model consists of two modules: an atmospheric boundary layer module and a pollutant dispersion module. Atmospheric boundary layer module This module is a second-order closure wind-field model ( Liu 1998 ), which is used to simulate the wind, turbulence, and temperature fields. Because the current study concentrates on simulating the vertical profiles of turbulence over flat and horizontally

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Franco Catalano and Antonio Cenedese

the ground up to about 200 m; a horizontal breeze directed from the center of the valley toward the slopes, extending from z ≅ 450 m to z ≅ 650 m; a strong updraft and an associated intense roll vortex over the ridge; a region characterized by a free convection regime near the east and west lateral boundaries; a return current in the upper part of the domain directed from the ridges toward the center of the valley with a vertical extension ranging from 600 m in proximity of the top of the

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Shuming Du and Akula Venkatram

Introduction This paper presents a parameterization of vertical dispersion in the surface layer. This scheme for estimating dispersion is meant to serve two purposes. One is to provide a compact description of the current understanding of dispersion in the surface layer. The second is to serve the same purpose as the widely used Pasquill–Gifford–Turner (PGT) scheme for vertical dispersion, which is to provide estimates of mean concentrations for practical industrial applications. An older

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John C. Wyngaard

will be of passing interest only. Except for rare critical ap praisals such as the 1968 Stanford contest for com putation of turbulent boundary layers, much of this work is never subjected to any kind of critical or com parative judgment. The only encouraging prospect is that current progress in understanding turbulence will restrict the freedom of such modeling and guide these efforts toward a more reliable discipline." Efforts to make critical assessments of these turbu lence models

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J. C. Kaimal and J. E. Gaynor

facility includes a 300 m towerinstrumented with fast- and slow-response sensors, a variety of remote sensing systems, and a real-timeprocessing and display capability that greatly reduces analysis time for scientists working with current orarchived data. In the past four years of operation the BAO has been the site of several large cooperativeexperiments and numerous smaller ones. Details of the data acquisition, processing and archiving schemesare presented. Results of studies conducted and

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