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Marc Olefs, Andrea Fischer, and Josef Lang

than the gradients of humidity and temperature as droplet speed mostly dominates the synoptic wind and is in the same order of magnitude from one snow gun to the other. Therefore the synoptic wind is not accounted for as a meteorological boundary condition in this study. If we neglect air pressure changes, expansion cooling is not a function of the meteorological boundary conditions. Furthermore, the calculation of the radiation balance is not straightforward: drop albedo is difficult to determine

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Sean C. Crosby, William C. O’Reilly, and Robert T. Guza

~60% of the total shoreward wave energy flux ( Fig. 2 ). Swell model prediction skill at nearshore buoy sites is compared for different offshore boundary condition parameterizations. Fig . 2. The 10-yr mean wave conditions at offshore buoy 071. (a) Mean GWM (NOAA-WW3) wave energy predictions (color) vs frequency and direction. (b) GWM- (dashed) and buoy-measured (solid) mean energy flux ( ) vs frequency (integrated over direction). Swell (0.04–0.09 Hz) and sea (0.09–0.25 Hz) frequency bands

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Ricardo P. Matano and Elbio D. Palma

presented numerical simulations of BTP showing no upstream spreading. They argued that a “realistic” model setup including a long estuary, a canyon at the mouth of the estuary, and the use of periodic (cyclic) boundary conditions prevents this phenomenon. In this article, we show that the lack of upstream spreading in the P11 simulations is an artifact created by the model’s boundary conditions—specifically, that simulations in periodic or closed domains develop a spurious cyclonic current that

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Piet Termonia, Alex Deckmyn, and Rafiq Hamdi

prediction (NWP) models on limited areas, the lateral boundary conditions (LBCs) have to be specified, but the existing numerical techniques used to impose them in operational models still exhibit, as Warner et al. (1997) properly address, a number of potentially serious limitations. A particular problem discussed in that paper is the one of the LBC temporal resolution . Warner et al. state that, “the time scales of the cross-boundary fluxes must be assessed, and the temporal resolution of the LBCs

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E. M. Lane, J. M. Restrepo, and J. C. McWilliams

alternative scalings and other averaging frameworks. In section 7 we summarize our view of the important elements in wave–current interaction. 2. Preliminaries a. Basic equations In the absence of body forces and dissipation, the equations of motion are with tracer equation The surface boundary conditions are and the bottom boundary condition is The physics and well-posedness considerations determine the lateral boundary conditions. The Eulerian velocity vector is U = ( Q , W ). The density is

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Qin Xu and Robert Davies-Jones

1566 MONTHLY WEATHER REVIEW VOLUM-121 Boundary Conditions for the Psi Equations QiN Xu CIMMS, University of Oklahoma, Norman, Oklahoma ROBERT DAVIES-JONES NOA,4 /ERL, National Severe Storms Laboratory, Norman, Oklahoma (Manuscript received 26 March 1992, in final form 16 November 1992) ABSTRACT

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Ivo G. S. van Hooijdonk, Herman J. H. Clercx, Cedrick Ansorge, Arnold F. Moene, and Bas J. H. van de Wiel

, it is unlikely that both parameters have the same physical meaning. Consequently, we may ask the following questions: How do these parameters relate to each other? What is their respective physical relevance? And what is their relevance for the SBL? To answer these questions, we perform DNS of the Couette flow with a fixed heat (or, more generally, buoyancy) flux (Neumann) boundary conditions (BCs) imposed at the top and bottom walls. We opt for DNS instead of large-eddy simulation (LES; e.g., as

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Katherine A. Lundquist, Fotini Katopodes Chow, and Julie K. Lundquist

1. Introduction Most mesoscale numerical weather prediction (NWP) models use terrain-following coordinates, which accommodate complex terrain by transforming the physical domain onto a Cartesian grid. Phillips (1957) first introduced this coordinate, using the variable sigma to represent the transformed vertical coordinate. This formulation simplifies the application of lower boundary conditions by aligning the lowest coordinate with the topography. Coordinate lines gradually

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William C. Skamarock, Michael G. Duda, Soyoung Ha, and Sang-Hun Park

forecasting for the foreseeable future. Regional models, however, bring with them a number of problems associated with their lateral boundary conditions, including questions concerning the well-posedness of the lateral boundary formulations, the potential for solution mismatches between the driving solution and the evolving regional solution, the need for relaxation or sponge zones next to the lateral boundaries, and issues related to the regional domain size and the degree of downscaling employed with a

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A. F. Bennett

176 JOUR. NAL OF THE ATMOSPHERIC SCIENCES VOLUME33Open Boundary Conditions for Dispersive Waves A. F.Geophysics! Fluid Dynamics Laboratory, Monaxh University, Clayton, Victoria 3168, Australia (Manuscript received 22 July 1975, in revised form 9 October 1975)AItSTRP~CT Approximate outgoing radiation conditions have been widely used at open boundaries in dispersive wavecomputations

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