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Behzad Abareshi and Peter H. Schuepp

important guideline for future work:if a neural network is to be designed for estimating sensible heat flux on a large scale, it should incorporate variables that serve as indices for canopy morphology and soil moisture. Recent advances in remote sensing techniques for land-use classification (e.g., Sellers et al. 1995a ) and soil moisture estimation (e.g., Engman and Chauhan 1995 ), an emerging wave of new and improved remote sensing data from the Boreal Ecosystem Atmosphere Study (BOREAS) ( Sellers

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Chien-Ming Wu, Bjorn Stevens, and Akio Arakawa

– 1883 . Bechtold , P. , J-P. Chaboureau , A. Beljaars , A. Betts , M. Kohler , M. Miller , and J-L. Redelsperger , 2004 : The simulation of the diurnal cycle of convective precipitation over land in a global model. Quart. J. Roy. Meteor. Soc. , 130 , 3119 – 3137 . Betts , A. , and C. Jakob , 2002 : Study of diurnal cycle of convective precipitation over Amazonia using a single column model. J. Geophys. Res. , 107 , 4732 . doi:10.1029/2002JD002264 . Chaboureau , J

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Shari J. Kimmel, John C. Wyngaard, and Martin J. Otte

-chipper scalar component, which would not be present in experiments and simulations but would be inherent in field observations. To approximate the fraction of the variance that could be due to the log-chipper scalar in observations, we estimated a mesoscale gradient variance for potential temperature over land from a HAPEX dataset ( Mahrt 1991 ). From (50) we computed a representative mesoscale gradient variance of ≈ 0.018 K 2 km –2 , which gives = 0.008 K 2 using (47) with a = 0.2 and z i

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R. H. White, J. M. Wallace, and D. S. Battisti

on the distribution of sea surface temperatures (SSTs). Using a comprehensive GCM Brayshaw et al. (2008 , 2009) explored the influence of idealized landmasses (e.g., rectangular continents), orography (e.g., Gaussian shaped mountains), and SST gradients. In this study we focus only on the influence of present-day orography versus land–sea contrast. In comparison with stationary waves, less attention has been paid to the impact of orography on the axisymmetric (zonal mean) flow. Held et al

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M. Mester and J. G. Esler

of capturing the vortex location, shape, and orientation. The best fit ellipse is calculated using the integral moments of the field in question, and then choosing the ellipse to match. The resulting time series of the vortex centroid, area, aspect ratio, and orientation provide a detailed picture of the climatology, interannual variability, seasonal cycle, and vertical structure of the vortices in each hemisphere [see, in particular, Waugh and Randel (1999) ]. Subsequent authors (e

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Hyo-Seok Park, Shang-Ping Xie, and Seok-Woo Son

“noT” refers to the no-Tibet simulation. We use Δ(·) to denote the differences between the full-Tibet and no-Tibet (Tibet − no-Tibet) runs. Consistent with Eqs. (1) and (2) , c p is multiplied and dp / g is multiplied and integrated from the surface to 300 hPa. The tilde denotes a long-term climatological mean, and the short overbar again denotes a 20-day moving average. The left-hand side of Eq. (5) is not exactly balanced by the right-land side. This is because the eddy heat flux of the

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Melinda S. Peng, John H. Powell, R. T. Williams, and Bao-Fong Jeng

intensifies through an imposed horizontal deformation field that moves with the mean wind. The boundary layer effect is parameterized using the multilayer K -theory (KA82) in which the mixing coefficients are determined by the local Richardson number. The frontal development with surface friction over a flat land produces similar results to those in KA82. The strengthened jet at the warm edge of the front is located at the top of the boundary layer, and the vertical mixing produces a nontilting frontal

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Gregory J. Tripoli

is relatively simple, limiting its influence on mesoscale organization; and 5) cold air outbreaks resulting in wind-parallel roll convection occur predictably virtually every season. As part of this study, the University of Wisconsin (UW) set up its Volume Imaging Lidar (VIL) on the windward shore to observe the earliest stages of development of the unstable boundary layer within the frictionally driven boundary layer moving off the land. In this paper, wind-parallel bands observed during the 10

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William L. Physick

1 NOVEMBER 1988WILLIAM L. PHYSICK3169 ,Mesioscale Modeling of a Cold Front and Its Interactionwith a Diurnally Heated Land Mass WILLIAM L. PHYSICKDepartment of Atmospheric Science, Colorado State University, Fort Collins, Colorado (Manuscript received 16 October 1987, in final form 9 May 1988)ABSTRACTA mesoscale numerical model incorporating a detailed planetary boundary-layer scheme, including momentum,heat and moisture exchange with the lower boundary, is used to study the

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Youtong Zheng

of satellite retrieval of CCN concentration by using natural clouds as CCN chambers ( Rennó et al. 2013 ; Rosenfeld et al. 2014a , 2016 ). This updrafts– z b relationship has been applied universally regardless of the underlying surface type: land or ocean (e.g., Rosenfeld et al. 2016 , 2019 ; Yue et al. 2019 ). Experimental data show that the relationship of cloud-base updrafts versus z b is ~20% steeper over land than that over the ocean, but the scatter of the samples, in particular

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