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David J. Stensrud and Jon A. Skindlov

) is used for the coarse-grid portion of the model domain. Planetary boundary layer: The model incorporates a modified version of the Blackadar ( 1976, 1979) high- resolution planetary boundary layer parameterization scheme ( Zhang and Anthes 1982; Zhang and Fritsch 1986) . A force- restore slab model is used to calculate surface temperature over land ( Blackadar 1979; Zhang and Anthes 1982) . Both the shortwave and downward longwave radiation components are affected by the cloud

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Shiqiu Peng, Yineng Li, Xiangqian Gu, Shumin Chen, Dongxiao Wang, Hui Wang, Shuwen Zhang, Weihua Lv, Chunzai Wang, Bei Liu, Duanling Liu, Zhijuan Lai, Wenfeng Lai, Shengan Wang, Yerong Feng, and Junfeng Zhang

( Landman et al. 2005 ; Giorgi 2006 ), the choice of horizontal resolutions for the nested domain, the selected microphysics parameterization scheme ( Rao and Prasad 2007 ; Kanada et al. 2012 ; Kepert 2012 ) or/and planetary boundary layer (PBL) parameterization scheme ( Khain and Lynn 2011 ; Pattanayak et al. 2012 ), as well as their combination ( Zhou et al. 2013 ). This paper introduces a real-time regional forecasting system established for the SCS whose atmosphere model features a “dynamical

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Jongil Han, Marcin L. Witek, Joao Teixeira, Ruiyu Sun, Hua-Lu Pan, Jennifer K. Fletcher, and Christopher S. Bretherton

1. Introduction The planetary boundary layer (PBL) scheme in the National Centers for Environmental Prediction’s (NCEP) Global Forecast System (GFS) adopts an eddy-diffusivity countergradient (EDCG) mixing approach ( Deardorff 1966 ; Troen and Mahrt 1986 ; Hong and Pan 1996 ; Han and Pan 2011 ) to take into account nonlocal transport by strong updrafts in the daytime convective boundary layer (CBL). Although the GFS EDCG PBL scheme provides a realistic CBL development projection despite its

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Heather Dawn Reeves, Kimberly L. Elmore, Geoffrey S. Manikin, and David J. Stensrud

1989 ; Whiteman et al. 1999 ; Reeves and Stensrud 2009 ). Because the air within a VCP is decoupled from the free atmosphere by a capping stable layer, VCP winds are generally quite weak. Very long-lived VCPs are often associated with severe air pollution and dense fog due to the lack of vertical mixing associated with the weak low-level winds (e.g., Hill 1993 ; Smith et al. 1997 ; Pataki et al. 2005 ; Struthwolf 2005 ). Warm-cloud precipitation systems moving over a subfreezing VCP can

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Yeong-Min Cha, Hwa-Woon Lee, and Soon-Hwan Lee

, or at the rear of mountains and islands near the coast ( Kang and Kimura 1997 ). Kristovich and Steve (1995) showed that multiple wind-parallel cloud bands were the most common phenomena of planetary boundary layer convection over warm lakes and their formation is strongly associated with the heat transitions between cold-air outbreaks and warm lakes. Using numerical model and observation data analysis, Cooper et al. (2000) simulated that the lower-level wind field, including wind shear, is

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Kay Sušelj, Timothy F. Hogan, and João Teixeira

. , 56 , 261 – 274 , doi: 10.1007/BF00120423 . Bogenschutz, P. A. , Gettelman A. , Morrison H. , Larson V. E. , Schanen D. P. , Meyer N. , and Craig C. , 2012 : Unified parameterization of the planetary boundary layer and shallow convection with a higher-order turbulence closure in the Community Atmosphere Model: Single-column experiments . Geosci. Model Dev. , 5 , 1407 – 1423 , doi: 10.5194/gmd-5-1407-2012 . Brown, A. R. , and Coauthors , 2002 : Large-eddy simulation of the

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Benjamin J. E. Schroeter, Phil Reid, Nathaniel L. Bindoff, and Kelvin Michael

atmospheric conditions both at the surface and throughout the atmospheric column above. The standard geopotential height for analysis in the Antarctic region is 500 hPa as it is the first mandatory reporting geopotential height level that is located everywhere above the ice surface ( Pendlebury et al. 2003 ). In addition, as the 500-hPa surface is also above the planetary boundary layer in the free atmosphere, its flow is in near-geostrophic balance and not influenced by surface effects such as friction

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Rich F. Coleman, James F. Drake, Michael D. McAtee, and Leslie O. Belsma

Microscale Meteorology Division of the National Center for Atmospheric Research (NCAR). The Aerospace Corporation produces high spatial (5 km × 5 km) and temporal (hourly) resolution forecasts for a two-level nested domain over the southern California region (see Fig. 1 ). The MM5 forecasts showed a persistent warm bias averaging between 1° and 2°C (depending on the model planetary boundary layer scheme), with a maximum overprediction in the late morning to early afternoon hours ( McAtee et al. 2006

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Young-Joon Kim, William Campbell, and Benjamin Ruston

1. Introduction The stratospheric polar winter circulation sometimes experiences sudden stratospheric warming (SSW; Scherhag 1952 ), which is characterized by a rapid breakdown of the polar vortex, an increase of the polar stratospheric temperature, and a reversal of the stratospheric polar night jet. SSW events are caused by the breaking of vertically propagating planetary waves originating from the troposphere ( Matsuno 1971 ; Simmons and Strüfing 1983 ; Mechoso et al. 1985 ; Andrews et

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Fan Zhang, Ming Li, Andrew C. Ross, Serena Blyth Lee, and Da-Lin Zhang

. Storm surge prediction has also been shown to be sensitive to atmospheric forcing ( Peng et al. 2004 ; Weisberg and Zheng 2006 ; Irish et al. 2008 ; Rego and Li 2009 ). Earlier studies used idealized wind models such as parametric surface winds that assume an idealized stationary, symmetric cyclone ( Peng et al. 2004 ), or the planetary boundary layer (PBL) hurricane wind model ( Scheffner and Fitzpatrick 1997 ). In a numerical study of storm surges in the Albemarle–Pamlico Sound for 10

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