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Paul J. Neiman and Roger M. Wakimoto

provided detailed measurements documenting the process. Based on an analysis of surface mesonet data, Koch and McCarthy (1982) proposed that the approach of a front can promote frontogenetical circulations along the dryline that enhance upward motion, which, subsequently, initiates convection. The summary article by Keyser and Shapiro (1986) shows analytically derived, deep tropospheric vertical circulations associated with fronts that could conceivably interact with drylines to initiate convection

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Yunhee Kang, Jong-Hoon Jeong, and Dong-In Lee

( Tsuboki and Sakakibara 2002 , 2007 ). Downward longwave radiation includes the effects of clouds and water vapor, and the downward shortwave radiation absorbed by the ground is considered ( Kondo 1976 ). Nondimensional bulk coefficients were adopted using land surface schemes ( Louis et al. 1982 ). A time-splitting scheme ( Klemp and Wilhelmson 1978 ) is adopted in the CReSS model to integrate the acoustic mode terms and gravity mode to improve (or enhance) computational efficiency. The filter

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Dimitris Menemenlis, Ichiro Fukumori, and Tong Lee

. Atmos. Oceanic Technol , 14 , 1420 – 1443 . Menemenlis , D. , and M. Chechelnitsky , 2000 : Error estimates for an ocean general circulation model from altimeter and acoustic tomography data. Mon. Wea. Rev , 128 , 763 – 778 . Menke , W. , 1989 : Geophysical Data Analysis: Discrete Inverse Theory. International Geophysics Series, Vol. 45, Academic Press, 285 pp . Paulson , C. A. , and J. J. Simpson , 1977 : Irradiance measurements in the upper ocean. J. Phys. Oceanogr , 7

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Shane D. Mayor

Study (CHATS; Patton et al. 2011 ). Table 1 lists the specifications of the lidar at the time of the deployment. The primary objective of deploying REAL at CHATS was to test the lidar’s ability to detect turbulent coherent structures in the atmospheric surface layer just above a forest canopy. Secondary objectives included monitoring the boundary layer depth and structure of the lower atmosphere that the in situ measurements were embedded within. The REAL was located 1.61 km north (38°30′8″N, 121

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Christopher C. Weiss, David C. Dowell, John L. Schroeder, Patrick S. Skinner, Anthony E. Reinhart, Paul M. Markowski, and Yvette P. Richardson

field phase in 2009, 14 of these probes were classified as type “A” ( Fig. 1a ), with separate instrument components dedicated to the sampling of individual atmospheric state variables (temperature, humidity, pressure, and wind). Ten probes, referred to as type “B” ( Fig. 1b ), utilized the Vaisala WXT510 (upgraded to WXT520 for 2010) all-in-one sensor, which collects all state variables within the same instrument housing. Rainfall and hailfall are additionally sensed acoustically in the type

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Peter T. May and Deepak K. Rajopadhyaya

. The resulting Doppler spectra were then stored for reanalysis. The profilers measure the radar backscatter from both turbulent irregularities (giving an estimate of the vertical wind) and precipitation particles (both rain and ice; e.g., Fukao et al. 1985 ; Larsen and Rottger 1987 ; Wakasugi et al. 1986 ; May 1991 ; Chilson et al. 1993 ). The profiler spectra have been reanalyzed to remove the effects of precipitation echoes from the estimates of the mean vertical motion. A least squares

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Peter J. Rogers and Richard H. Johnson

low-level cool, moist air northward along the GOC during the NAM. Hales (1972) suggested that a natural channel exists along the GOC [Baja peninsular ranges to the west and Sierra Madre Occidental (SMO) to the east] for gulf surge propagation ( Fig. 1 ). Because of decreased frictional effects over water, gulf surges are strongest over the GOC and continue most forcefully up the Colorado River basin upon reaching the northernmost extent of the GOC ( Hales 1972 ; Brenner 1974 ). Hales (1972

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Shiyuan Zhong, C. David Whiteman, Xindi Bian, William J. Shaw, and John M. Hubbe

temporal information to allow detailed investigations of some cold pool evolution processes. Recent advances in remote sensing instruments and computational power along with improvements in model parameterizations and numerical algorithms have made detailed studies of cold pools possible so that an in-depth understanding of the processes affecting cold pool formation and destruction can be achieved. During the period from 1 November 1998 to 1 March 1999, measurements using in situ and remote sensing

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Phillip L. Spencer, Frederick H. Carr, and Charles A. Doswell III

demonstration network(WPDN) across the central United States in 1992, accurate wind measurements throughout the depth of thetroposphere at sites with an average spacing of roughly270 km are available on an hourly basis. This provideshigh temporal and vertical resolution diagnoses oftrough and ridge passages, upslope and downslopewind events along the Rocky Mountains, low-level jets,and jet streaks, just to name a few phenomena. Not onlydoes the profiler network allow us to diagnose theseprocesses in

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Keith M. Hines and David H. Bromwich

). The model is integrated in time with a third-order Runge–Kutta scheme with smaller time steps for acoustic waves and gravity waves. Model variables are horizontally staggered on an Arakawa grid-C, and the model top is a constant pressure surface. Similar to MM5, multiple nested grids with one- or two-way interaction are possible. The data assimilation capabilities of the WRF-Var program are adapted from MM5 3DVAR ( Barker et al. 2003 , 2004 ). Multiple physics package options allow flexibility in

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