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Xiaoming Shi, Rica Mae Enriquez, Robert L. Street, George H. Bryan, and Fotini Katopodes Chow

to the dynamic reconstruction turbulence closure model (DRM) ( Chow et al. 2005 ; Shi et al. 2018 ) at both LES and TI resolutions. iGLASS has similar computational cost to DRM. Because iGLASS has been extended in a new code, CM1, we first evaluate iGLASS in a dry neutral boundary layer (NBL) case ( section 3 ). Then we move on to testing and analyzing the performance of iGLASS in the challenging case of the stratocumulus-capped boundary layer (SCBL) at both LES and TI resolutions ( section 4

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Kuan-Man Xu and David A. Randall

1 NOVEMBER 1996 XU AND RANDALL 3103Evaluation of Statsfically Based Cloudiness Parameterizations Used in Climate Models KUAN-MAN Xu AND DAVID A. RANDALLDepartment of Atmospheric Science, Colorado State University, Fort Collins, Colorado(Manuscript received 29 December 1995, in final form 15 April 1996)ABSTRACT Existing cloudiness parameterizations based on specified probability

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H. M. Christensen, I. M. Moroz, and T. N. Palmer

, at a resolution of T159 by Ollinaho et al. (2013a) for forecasts initialized in May–August 2011. The SPPT and SKEB stochastic physics schemes were used to represent model uncertainty. The cost function used was the root-mean-square error (RMSE) in 500-hPa geopotential height (Z500), evaluated globally at a lead time of 3 and 10 days. The two lead times were scaled to contribute the same order of magnitude to the cost function. Z500 is chosen for the cost function because this variable is

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Yuan Sun, Lan Yi, Zhong Zhong, and Yao Ha

smooth transition to an explicit simulation of cloud-scale processes as the resolution increases ( Arakawa and Wu 2013 ). It behaves similarly to conventional schemes when the updraft area is much smaller than the grid size. As the updraft area in a grid box approaches the grid size, the parameterized subgrid convection gradually decreases ( Grell et al. 2013 ). In this paper, we evaluate the GF13 performance on the aforementioned model convergence at the gray-zone resolutions based on a case study

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Y. C. Sud and G. K. Walker

recent research on improvement of physical parameterizations in the GLA GCM. Physical Processes in Atmospheric Models, D. R. Sikka and S. S. Singh, Eds., Wiley, 422–479. ——, and ——, 1993: A rain evaporation and downdraft parameterization to complement a cumulus updraft scheme and its evaluation using GATE data. Mon. Wea. Rev., 121, 3019–3039. ——, and ——, 1999: Microphysics of clouds with the Relaxed Arakawa–Schubert Scheme (McRAS). Part II: Implementation and Performance in GEOS II GCM. J

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J. Berner, G. J. Shutts, M. Leutbecher, and T. N. Palmer

In this section we propose the use of the spectral backscatter scheme in conjunction with reduced initial perturbations as an alternative to the operational ensemble configuration. Because the initial perturbations in OPER are tuned for optimal performance, this is the most challenging comparison. The following section will hence concentrate on the comparison of SSBS-FULLDISS and OPER and describe the impact of SSBS-FULLDISS on different aspects of model error, such as kinetic-energy spectra, the

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E. A. Smith, J. E. Lamm, R. Adler, J. Alishouse, K. Aonashi, E. Barrett, P. Bauer, W. Berg, A. Chang, R. Ferraro, J. Ferriday, S. Goodman, N. Grody, C. Kidd, D. Kniveton, C. Kummerow, G. Liu, F. Marzano, A. Mugnai, W. Olson, G. Petty, A. Shibata, R. Spencer, F. Wentz, T. Wilheit, and E. Zipser

predominantly land background ideal settings for evaluating PMW algorithm performance over water. Because a final refereed analysis of the AIP-2 results has yet to be published, the preliminary conclusion concerning the near-equivalent performance of IR and PMW algorithms remains uncertain. The AIP-3 project attracted 52 algorithms from 24 research groups, consisting of 22 IR algorithms or mixed IR algorithms (IR/VIS or IR/PMW) and 29 PMW-only SSM/I algorithms. (Of the latter, 20 are candidates for

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Tongwen Wu, Rucong Yu, and Fang Zhang

the paper is as follows: A set of modified atmospheric governing equations for the National Center for Atmospheric Research (NCAR) Community Atmosphere Model version 3 (CAM3) are described in section 2 . Section 3 gives the details of time differencing and the vertical finite difference scheme, which originate from the Eulerian dynamic core in CAM3 described by Collins et al. (2004) . To evaluate its performance compared to the original dynamic, the modified spectral dynamic framework is

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Aijun Deng, Nelson L. Seaman, and John S. Kain

, deformation, and other dynamical effects that occur in 3D models. The design of the experiments is explained in section 3 . One test case evaluates model performance in a slowly changing marine environment, while the other three cases represent a variety of more strongly forced continental conditions. Results of the model-evaluation experiments are given in section 4 , while section 5 presents additional tests that explore the sensitivity of solutions to model vertical resolution, key aspects of the

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Davide Panosetti, Steven Böing, Linda Schlemmer, and Jürg Schmidli

convection and precipitation within a thermally driven flow is performed using LES modeling over idealized mountain ridges. A primary focus is on the role of moisture transport by the upslope winds and of vertical mixing. CRM simulations are also run to investigate the performance of a coarser-resolution model in reproducing the discussed mechanisms. In the CRM simulations, different turbulence schemes and a shallow convection parameterization are tested to understand if an optimal configuration exists

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