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Werner Metz

transient vorticity fluxes arising from the interactions between the planetary wavesand the synoptic-scale eddies is considered. This forcing effect is stochastically modeled in terms of a combinedMarkov-complex EOF approach. The performance of these stochastically modeled vorticity fluxes is evaluatedin the framework of a simple barotropic dynamical model.It turns out that the forcing is highly coherent in wavenumber space, i.e., local in physical space, and thatthis organization is largely associated

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Jing Huang, Elie Bou-Zeid, and Jean-Christophe Golaz

et al. 2004 ) and systematically evaluated using the steady-state test cases, as well as new cases with unsteady surface forcings. This paper is structured as follows. In section 2 , the GFDL SCM and the test cases are briefly introduced. In section 3 , we examine the applicability of the gradient-flux hypothesis across varied stabilities. The new mixing-length model is then introduced in section 4 . We run test cases with steady and unsteady surface forcings to assess the performance of the

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Young-Joon Kim and Akio Arakawa

-scale orography is now included in most existing largescale models of the atmosphere. Parameterization schemes, however, have so far been evaluated mainly in viewof the overall performance of the large-scale models. This may lead to an inappropriate assessment of the schemessince errors from various sources may interact with one another. To avoid this situation, an approach is takenin which a numerical model that explicitly resolves gravity waves is used to evaluate the performance of theschemes. For this

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Catherine Gautier and Martin Landsfeld

flux during the experiment over an area typically covered by the grid cell of a general circulation model (GCM). This information is expected to help general circulation modelers involved in ARM projects develop improved parameterizations of clouds and their interaction with radiation in their models through validation of their results with our satellite derived parameters. In this paper, section 2 describes the main features of the radiative transfer model 2001. Section 3 evaluates the

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John S. Kain and J. Michael Fritsch

idealized co.retire environments a~ demon~rated and its sensitivities toseveral key control parameters are exam/ned. Finally, the performance of the new model in the Fr/tsch-ChappellCPS is.evaluated. Parameterized heating and drying profiles are clue/dated as they relate to the convectiveenvironment and to the type of cloud model used in the CPS.1. Introduction Moist convective processes in the atmosphere occuralmost exclusively on spatial scales smaller than thoseexplicitly resolved by numerical

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David D. Houghton and Robert M. Chervin

fluxcomponents highlighting the relative characteristics of the fundamental time-domain elements. Results from5 and 2.5- horizontal resolution versions of the model demonstrate the impact of truncation error on mode[simulations of these flux statistics. Comparing grid point measures constitutes a more stringent model performance evaluation since regionaldifferences between observed and simulated transports often are found to be considerably larger than zonallyaveraged differences. Such regional

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B. A. White, A. M. Buchanan, C. E. Birch, P. Stier, and K. J. Pearson

between configurations. Pearson et al. (2013) give a full description of the model configurations. We present data from 9 days of simulation initialized using analyses from the European Centre for Medium-Range Weather Forecasts (ECMWF) at 0000 UTC 26 July 2006. The 9-day sample is sufficient to reach a state where the results robustly represent the model performance (see appendix A ). Boundary forcing from ECMWF analyses was every 6 h for 12kmParam and 12kmExp. The high-resolution simulations

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Kerry A. Emanuel and Marina Živković-Rothman

independent data, preferably from a large number of different sounding arrays sampling very different convective regimes. Unfortunately, very few such datasets exist. As a first step in evaluating the performance of the optimized scheme, we force the single-column model using data collected during the Global Atmospheric Research Program Atlantic Tropical Experiment (GATE), conducted in the eastern tropical North Atlantic in 1974. The time evolution and all the advections of temperature and specific

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G. J. Steeneveld, B. J. H. van de Wiel, and A. A. M. Holtslag

is not a limiting factor. Therefore, we evaluate the performance of a single-column model for all three SBL archetypes (fully turbulent, intermittently turbulent, and radiative) at high vertical resolution as a proof of principle. We will in particular explore the modeling of soil and vegetation because the soil heat flux is a relatively large component of the surface energy budget during nighttime. We will compare our results with observations from the extensive 1999 Cooperative Atmosphere

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Jerry Y. Harrington, Michael P. Meyers, Robert L. Walko, and William R. Cotton

consisting ofparticles with mean sizes less than 125/~m, while snow is the large class consisting of particles greater than 125/zm. Analytical equations are formulated for the conversion between the ice classes by vapor deposifional growth(sublimation). During ice subsaturated conditions, a number concentration sink is parameterized for all icespecies. The performance of the parameterizations in a simple parcel model is discussed and evaluated againstan explicit Lagrangian parcel microphysical model.1

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