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J. B. Jalickee and C. F. Ropelewski

).The structure sondes have an ascent rate of 3 m s-~890 890910930950~?0990910~ t ~ ]~First /Com 298 300and a sampling rate 0.5 hz to provide high-resolution measurements of pressure, wet-bulb temperature and dry-bulb temperature from the surface to700 mb. (WMO, 1975). These sondes were scheduledto be launched at 3 h intervals starting at 0100 hfrom each of the ships that formed the C-array,the Fay, Meteor and Planet (Fig. 1). The data, obtained from the

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Jeremy A. Gibbs, Evgeni Fedorovich, Björn Maronga, Charlotte Wainwright, and Manuel Dröse

1. Introduction Knowledge of parameters of atmospheric turbulence within the planetary boundary layer is needed for many applications including pollutant dispersion modeling, wind engineering, weather forecasting, aviation, and prediction of electromagnetic and acoustic wave propagation. The latter group of applications, in particular, requires information on the so-called structure functions of the atmospheric flow fields that characterize turbulent fluctuations of atmospheric physical

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Steven E. Koch, F. Einaudi, Paul B. Dorian, Stephen Lang, and Gerald M. Heymsfield

entire horizontal wavelength of the 135-km-scale gravity wave,which made direct comparisons difficult. Furthermore, the linear theory predicts much smaller amplitudes andsomewhat longer horizontal wavelengths for the vertical motions characterizing both wave modes than thoseseen in the Doppler winds, which likely also contain nonwave effects. These discrepancies are largely due to thecombined effects of weak convection, turbulence, and data sampling problems. Despite these drawbacks, thefindings from

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C. Warner, J. Simpson, D. W. Martin, D. Suchman, F. R. Mosher, and R. F. Reinking

responded well to sudden changes. Effects of rain on temperature measurements--a notorious problem--are not involvedhere. Penetrated clouds were small; therefore effects of sensor wetting are neglected. At the right ofFig. 11 uncertainty bars for density may be found: anincrease in density corresponding to the bars couldbe caused by changes of -0.2-C in T or -1.2-C inTD. Changes in plotted densities slightly exceededthose indicated by the uncertainty bars. Potentialtemperatures fluctuated relatively

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Anna Borovikov, Michele M. Rienecker, Christian L. Keppenne, and Gregory C. Johnson

time. In the case of observational errors, the matrix R is often assumed to be diagonal and to contain only information about the level of variance in the measurement error due to instrumental imperfection and unresolved small-scale signal. There are means of allowing for simple time evolution of the forecast error variance (see, e.g., Ghil and Malanotte-Rizzoli 1991 ; Rienecker and Miller 1991 ), but they are not considered here. A full evolution of 𝗣  f k would be a Kalman filter. The

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Jeffrey S. Gall, William M. Frank, and Young Kwon

in the transfer of both enthalpy and momentum between the air and sea in high-wind conditions. Reentrant sea spray enhances the net enthalpy flux between sea and air. Both reentrant and fully evaporating sea spray act as a momentum sink, in that they extract momentum from the near-surface layer. This effect in turn moderates the effects of the net spray enthalpy flux. The authors found that including both enthalpy and momentum effects due to spray produced model results similar to simulations

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J. R. Garratt, P. A. C. Howells, and E. Kowalczyk

coldair. The low-level flow is at the same time intimatelyconnected with the lower branch of the transversefrontal circulation, so that frontal dynamics, andmovement, must be partly under large-scale control.Clearly, fronts and their development (frontogenesisand frontolysis) depend on a number of factors, fromthe synoptic scale (t'.g., the large-scale combination ofhorizontal shear and deformation acting on preexistingtemperature gradients), to the small scale (e.g., turbulent effects in the boundary

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C. E. Dorman, L. Armi, J. M. Bane, and D. P. Rogers

the Santa Barbara Air Pollution Control District. Radar profiler measurements were made at several coastal locations. Bill Neff at NOAA’s Wave Propagation Laboratory at Boulder had profilers at Fort Bragg and Santa Cruz (SCZ), the Naval Postgraduate School had a profiler at Fort Ord (FORD), and the USAF maintained three profilers at Vandenberg AFB (VBG). An acoustical sounder was operated at the Diablo Canyon Power Plant (DIA) by Pacific Gas and Electric Company. An instrumented light

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A. B. C. Tijm, A. A. M. Holtslag, and A. J. van Delden

breezes are also studied with the help of 2D and 3D numerical models. The first numerical study was performed by Estoque (1962) , who used a 2D model to study the effects of the temperature difference and the large-scale wind on the development of the sea breeze. One of the first 3D studies was performed by Pielke (1974) , whereas recently Bechtold et al. (1991) and Arritt (1993) use 2D models to study sea breezes under a wide range of conditions (i.e., large-scale winds, stability). The most

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Steven E. Koch and Robert E. Golus

analysis have generated problems of varying degreesof seriousness in such studies. Four general problemareas are those arising from - the effects of aliasin~ - erroneous estimates of wave phase velocity - inaccurate determination of the relative phasingbetween the waves and convection - the inability to identify individual wave ridges andtroughs.With the single exception of Koch (1979), the wavesin the above case studies, as well as others by Brunk(1949), Miller and Sanders (1980), and Vincent

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