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Eric P. James and Richard H. Johnson

mean elevation of all OM stations) and subtracting the mean diurnal pressure signal during the calendar month of interest. In addition, virtual temperature observations from NPN stations equipped with a Radio Acoustic Sounding System (RASS) are linearly interpolated to 25-hPa pressure increments in the vertical, and then linearly interpolated in time, to diminish the extent of missing data. Virtual temperature anomalies are calculated by subtracting the mean virtual temperature from the

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Ronald L. Holle, Joanne Simpson, and Steven W. Leavitt

penetrated for boundarylayer measurements (Barnes, 1977; Gaynor andMandics, 1978). In this report, we will relate cloudsto those in the Barbados area and the equatorial , Present affiliation: Department of Oeosciences, University ofArizona, Tucson 85721.0027-0644/79/070874-22509.50c 1979 American Meteorological Societytrough, study cloudiness changes through the dailycycle, compare cloud cover to satellite and radardata, and correlate cloudiness with net radiation. Whole-sky photographs were also

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Brice E. Coffer and Matthew D. Parker

( Wilhelmson and Chen 1982 ). The lowest scalar grid level is at 10 m, and from there, the vertical grid spacing stretches from 20 m in the lowest 300 m to 280 m at 12 km, allowing for 31 levels in the lowest kilometer. The model time step was 0.6 s, with eight split time steps for the acoustic modes ( Klemp and Wilhelmson 1978 ). A fifth-order advection scheme, utilizing high-order-weighted essentially nonoscillatory finite differencing, is used with no additional artificial diffusion ( Wicker and

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Mingjing Tong and Ming Xue

. After applying pressure detrending, the pressure drift is much more controlled and the update of the pressure by analysis does reduce its error in general, though not as much as for other fields (cf. e.g., black curves in Figs. 4e and 4c ). At 40 min in the current experiment (VrP), the basic pattern of the perturbation pressure can be reasonably reconstructed (not shown). Noticeable noises associated with acoustic oscillations remain at low levels at this time, which are reduced by additional

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Pierre Tandeo, Pierre Ailliot, Marc Bocquet, Alberto Carrassi, Takemasa Miyoshi, Manuel Pulido, and Yicun Zhen

the underlying physics, including deficiencies in the numerical schemes, the cumulative effects of errors in the parameters, and the lack of knowledge of the unresolved scales. Its estimation is a challenge in general, but it is particularly so in geosciences because we usually have far fewer observations than those needed to estimate the entries of Q ( Daley 1992 ; Dee 1995 ). The sum of the two covariances P m and Q gives the forecast covariance matrix, P f (full green ellipse in Fig

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Paul G. Wolyn and Thomas B. Mckee

: Ambient wind effects on the initiation and development of cumulus clouds over mountains. J. Atmos. Sci., 25, 385-403.Pielke, R. A., W. R. Cotton, R. L. Walko, C. J. Tremback, W. A. Lyons, L. D. Grasso, M. E. Nicholls, M. D. Moran, D. A. Wes ley, T. J. Lee, and J. H. Copeland, 1992: A comprehensive me teorological modeling system--RAMS. Meteor. Atmos. Phys., 49, 69-91.Schneider, J. M., 1991: Dual Doppler measurement of a sheared, convective boundary layer. Ph.D. dissertation. University of

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Chad M. Shafer, Andrew E. Mercer, Charles A. Doswell III, Michael B. Richman, and Lance M. Leslie

development of NCEP–NCAR reanalysis data results in the removal of any data considered grossly erroneous (whether by instrumentation error, human error, communication problems, etc.) and observations containing “large errors of representativeness that are accurate but whose measurements represent spatial and temporal scales impossible to resolve properly in the analysis-forecast system” ( Kalnay et al. 1996 , 446–447). Since this dataset consists of horizontal and vertical grid spacings consistent with

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Stephen S. Weygandt, Alan Shapiro, and Kelvin K. Droegemeier

-observed reflectivity is truncated at 50 dB Z prior to the calculation of the rainwater mixing ratio. Water vapor and cloud water effects are neglected in the thermodynamic retrieval. Again, following Ellis (1997) , and based on our own experience, the retrieved pressure and potential temperature are only retained within the reflectivity volume. Outside the reflectivity region, pressure and temperature are set to base-state values (obtained from the proximity sounding). As a last step in the retrieval process

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Benedikt Ehard, Peggy Achtert, Andreas Dörnbrack, Sonja Gisinger, Jörg Gumbel, Mikhail Khaplanov, Markus Rapp, and Johannes Wagner

. 2006 ), radars (e.g., Stober et al. 2013 ), airglow imagers (e.g., Suzuki et al. 2010 ), noctilucent cloud images (e.g., Pautet et al. 2011 ), satellite measurements (e.g., Alexander et al. 2008 ), radiosonde soundings (e.g., Dörnbrack et al. 1999 ; Zhang and Yi 2005 ), and rocket soundings (e.g., Rapp et al. 2004 ). However, these instruments are limited to particular altitude ranges and are only sensitive to a distinct part of the gravity wave spectrum ( Gardner and Taylor 1998 ; Preusse

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Tammy M. Weckwerth and David B. Parsons

arrays. In the case of the National Weather Service sounding network, the experimental design included enhancing the number of soundings during periods of interest over a broad area. With this measurement strategy, the intent was to capture local ascent and circulations at the boundaries, capture the effects of any secondary, balanced circulations in preconditioning the environment, and to place these measurements in the synoptic context. To place this multiscale concept in historical prospective

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