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Nasrin Nasrollahi, Amir AghaKouchak, Jialun Li, Xiaogang Gao, Kuolin Hsu, and Soroosh Sorooshian

.g., precipitation, wind direction, and velocity) can play a significant role in reducing the vulnerability of our society to severe events. However, the prediction of precipitation structure is extremely challenging. Based on initial conditions, regional weather models currently estimate the state of the near-future atmosphere by solving atmosphere dynamic and thermodynamic equations. Some weather models include different physics options that describe the physical processes of the atmospheric phenomena. Two of

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Melissa A. Nigro, John J. Cassano, Jonathan Wille, David H. Bromwich, and Matthew A. Lazzara

additional knowledge of smaller-scale processes is required to adapt the current planetary boundary layer (PBL) and surface-layer parameterizations to the higher vertical resolution models ( Teixeira et al. 2008 ; Baklanov et al. 2011 ). A wide range of model errors exists with respect to simulating stable boundary layers. A common model error is the underrepresentation of the near-surface vertical temperature gradient, or an underrepresentation of the static stability ( Atlaskin and Vihma 2012 ; Sterk

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Patrick S. Market, Ronald W. Przybylinski, and Scott M. Rochette

the 25-km simulation ( Fig. 10 ) are derived from the hourly output from the 50-km MASS run. Both simulations feature a hydrostatic atmosphere with 21 vertical levels formulated in terrain-following σ -coordinates. Cumulus closure is provided by the a Kuo–Anthes scheme ( Kuo 1965 ; Anthes 1977 ) that has been modified to include moist downdrafts, while the planetary boundary layer is resolved with a 1½-order turbulent kinetic energy scheme ( Therry and Lacerrère 1983 ; Benoit et al. 1989

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Paul Fox-Hughes

ratio through the lowest third (or more) of the troposphere was about 2.6 g kg −1 , corresponding to a dewpoint temperature of −5°C at the surface. It is clear, then, that mixing had occurred through the lower several hundred hectopascals of the atmosphere by early afternoon. Fig . 8. (a) Routine radiosonde trace from the Hobart airport at 2300 UTC 6 Nov 2002. (b) Routine radiosonde flight at 0000 UTC 5 Nov 2002 from Eucla (Western Australia). Eucla is close to the position at 0000 UTC 5 Nov of the

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Travis H. Wilson and Robert G. Fovell

than that over flat terrain ( Whiteman 2000 ), but this may be at least partially counteracted by downward longwave radiation originating from the atmosphere and valley walls in a manner that may be dependent on valley size ( Whiteman et al. 2004 ). However, the role of drainage flows in cold pool formation is controversial. In some cases, drainage flows do not become detached from the basin walls and have been well observed flowing in valley locations ( Hootman and Blumen 1983 ; Gudiksen et al

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Neil Adams

grid and sigma coordinates in the vertical, with the ALAPS domain in this study having a resolution of 0.25° latitude × 0.50° longitude, giving an approximate horizontal resolution of 27.5 km. The model boundaries were from 80°–35°S and 0°–180°. Twenty-nine vertical sigma levels were used, ranging from 0.9988 near the surface (approximately 10 m) to 0.05 at the model upper boundary, with a concentration of levels in the planetary boundary layer. A full description of the model can be found in Puri

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Michael J. Brennan, Gary M. Lackmann, and Kelly M. Mahoney

.1175/1520-0493(1992)120<0893:AMASOT>2.0.CO;2 Rossby, C-G. , 1940 : Planetary flow patterns in the atmosphere. Quart. J. Roy. Meteor. Soc. , 66 , (Suppl.) . 68 – 87 . Shapiro, L. J. , and Möller J. D. , 2003 : Influence of atmospheric asymmetries on the intensification of Hurricane Opal: Piecewise PV inversion diagnosis of a GFDL model forecast. Mon. Wea. Rev. , 131 , 1637 – 1649 . 10.1175//2552.1 Sippel, J. A. , Nielsen-Gammon J. W. , and Allen S. E. , 2006 : The multiple-vortex nature of tropical

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Caroline Jouan, Jason A. Milbrandt, Paul A. Vaillancourt, Frédérick Chosson, and Hugh Morrison

state variables averaged in time and globally such as the planetary albedo (AP) and the radiative flux at the top of the atmosphere (TOA) and surface (SFC) give a good indication of the cloud radiative effect. Verification of the planetary albedo makes it possible to ensure good radiative balance of the model. Satellite observations indicate that the planetary albedo is near 30%–33% (ISCCP, Rossow and Zhang 1995 ). 4. Impacts of using P3 (and SCPF) in a global model In this section, we examine the

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Adam J. Deppe, William A. Gallus Jr., and Eugene S. Takle

for power generation, accurate forecasts are needed. Unfortunately, there have been few evaluations of model forecasts of winds at 80 m, a height where the influence of turbulent fluxes of momentum, heat, and moisture from the earth’s surface can vary greatly depending on the time of day, season, and vertical temperature stratification of the atmosphere. Meteorologists traditionally have focused wind forecasts at the 10-m level, a height at which official wind observations are routinely taken and

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Francisco Salamanca Palou and Alex Mahalov

-based predictive modeling tool for urban applications. Nevertheless, the authors never evaluated the Noah-MP LSM’s ability to reproduce the diurnal cycle of near-surface meteorology and surface skin temperature under wintertime weather conditions and neither the sensitivity of the results to the planetary boundary layer parameterization. Therefore, the aim of this paper is twofold: on one hand, to examine summer- and wintertime variations of the surface and near-surface urban heat island for a semiarid urban

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