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Feimin Zhang and Zhaoxia Pu

1. Introduction Landfalling hurricanes are a significant weather-related threat both onshore and inland. They cause great loss as a result of their strong winds, heavy rainfall, soil erosion, and flooding ( Wu and Kuo 1999 ; Kaplan and DeMaria 2001 ; Whitehead 2003 ). Accurate prediction of the track, intensity, and structure associated with the weakening of hurricanes during landfall and their further evolution over land is of great interest in order to provide effective warning. Yet this is

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Christian Barthlott and Norbert Kalthoff

1. Introduction Despite the advances in the parameterizations of physical processes and higher grid spacings of numerical weather prediction (NWP) models over the past decades, quantitative precipitation forecasting still remains a challenge. In particular, the forecast of deep moist convection with weak synoptic forcing is still inadequate for many applications. Besides uncertain initial and boundary conditions, inaccuracies of numerical methods and/or the incomplete description of physical

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Vladimir M. Gryanik, Christof Lüpkes, Andrey Grachev, and Dmitry Sidorenko

1. Introduction The atmospheric boundary layer is often stably stratified. This holds especially for polar regions but also for other regions on Earth where stable stratification is a very common feature, e.g., during night. However, turbulent processes in the stable boundary layer (SBL) are still poorly represented in climate and weather prediction models. In this work we study such processes with a focus on the parameterization of the turbulent surface-layer fluxes in the SBL. One of the key

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Duncan C. Blanchard

AUGUST 1958DUNCAN C. BLANCHARD383ELECTRICALLY CHARGED DROPS FROM BUBBLES IN SEA WATER AND THEIR METEOROLOGICAL SIGNIFICANCE By Duncan C. Blanchard Woods Hole Oceanographic Institution'(Original manuscript received 13 September 1957 ; revised manuscript received 3 April 1958)ABSTRACTA modification of Millikan's classic oil-drop experiment was used to determine the electric charge andradius of drops that were ejected from a bursting bubble at an air-sea water interface

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Clare S. Y. Huang and Noboru Nakamura

-amplitude Rossby waves and balanced eddies by introducing finite-amplitude wave activity (FAWA) based on the meridional displacement of quasigeostrophic potential vorticity (PV) from zonal symmetry. The formalism eliminates the cubic term from the right-hand side of (1) and extends the nonacceleration theorem ( Charney and Drazin 1961 ) for an arbitrary eddy amplitude. This allows one to quantify the amount of the mean-flow modification by the eddy ( Nakamura and Solomon 2010 , 2011 ). Despite its

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Qinglin Zheng and Kuo-Nan Liou

precipitation patterns over eastern Asia are physically investigatedemployjag a general circuiation model specifically designed for medium range weather prediction. The modelis a modification and improvement of the one recently presented by Liou and Zheng. Efficient and accuratenumerical techniques have been devised for the computation of the pressure gradient force and the initial fieldin the vicinity of mountains in the u-coordinate. In addiiton, a cumulus convection scheme and a liquid watercontent

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Jing Huang and Elie Bou-Zeid

1. Introduction The stable atmospheric boundary layer (SABL) forms when the underlying land surface is cooler than the air aloft. Typical SABLs, such as the nocturnal boundary layer and the polar boundary layer, significantly influence near-surface as well as large-scale atmospheric dynamics. Consequently, an in-depth understanding of the SABL is required for applications such as numerical weather prediction (NWP) and regional and global climate modeling. However, our current understanding of

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H. C. Davies, Ch Schär, and H. Wernli

provide insight upon the sensitivity of the flow responseto the lateral shear. At root it is shown to be related to two intrinsic symmetry features of the semigeostrophicsystem. In the quasi-linear phase of the development the shear induces a displacement of the critical-surface ofthe wave relative to the main baroclinic zone, a concomitant asymmetric modification in the structure of thenormal modes, and a substantial positive feedback upon the shear of the mean flow. The latter changes

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Kenneth Sassen, Arlen W. Huggins, Alexis B. Long, Jack B. Snider, and Rebecca J. Meitín

Utah/NOAA cooperative weather modification experiment, is divided into descriptions of the synoptic and kinematic properties in Part I, and stormstructure and composition here in Part II. In future parts of this series, the turbulence structure and indicatedcloud seeding potential will be evaluated. The analysis presented here in Part II focuses on multiple remotesensor and surface microphysical observations collected from a midbarrier (2.57 km MSL) field site. Thecollocated remote sensors were a

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Malakondayya Challa, Richard L. Pfeffer, Qiang Zhao, and Simon W. Chang

the results of the two integrations and in section 5 we show the diagnostics and discuss the mechanisms involved. Our conclusions are presented in section 6 . 2. Numerical model, data source, and initialization The numerical model employed for the present simulations ( Madala et al. 1987 ) is a modification of the one used in our previous simulations ( Challa and Pfeffer 1990 ). The primary modification is the inclusion of a more sophisticated boundary layer parameterization. This model has

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