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G. Brogniez, J. C. Buriez, V. Giraud, F. Parol, and C. Vanbauce

~propertiesderived from .ground-ba~ed measurements-are compared to those derived from satellite observations.2. Dataa. Ground-based measurements The measurements were acquired at Nordholz(53.8-N, 8.3-E) on 18 October 1989 during ICE'89 ( 18September-20 October 1989) (Raschke et al. 1990).The instruments in use were an aureolemeter, an infrared radiometer, and a lidar. Both the radiometei' and thelidar were" pointing toward the zenith, while the aureolemeter measured the forward-scattered light nearthe sun

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O. Coindreau, F. Hourdin, M. Haeffelin, A. Mathieu, and C. Rio

. Comparison with SIRTA observations To illustrate the performances of the model with the optimum parameterization (b10 + th), a 1-month period, corresponding to the VAPIC intensive observation period, has been more precisely studied. During this period, running from 18 May 2004 to 17 June 2004, observations performed by remote sensing and in situ instruments at the SIRTA observatory (weather station, cloud aerosol lidar, radiosonde measurements, and flux meters) are used to analyze simulated surface

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Stefan Kinne, Thomas P. Ackerman, Andrew J. Heymsfield, Francisco P. J. Valero, Kenneth Sassen, and James D. Spinhirne

atmospheric temperature profile is ~iven by the d~t-hand ordinate.of the FSSP probe measurements taken by the KingAir above 7 km. The ground-based lidar data define the cloud baseat or just above the 6-km altitude. This is consistentwith King Air cockpit VCR observations at 6.1 kmtaken during leg I and after the spiral descent, whensurface features were clearly visible. The uncertaintyin cloud-top height deduced from ground-based lidarMAY 1992 KINNE

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Paul J. Neiman, F. Martin Ralph, Robert L. Weber, Taneil Uttal, Louisa B. Nance, and David H. Levinson

Divide ( Fig. 1 ). Its narrow beamwidth (1.8 m at 20-km range) and lack of sidelobes provided detailed observations (≤300 m spatial and ≤1 min temporal resolutions) of radial velocity and backscatter within its ∼30 km observing radius. Because of the large amount of volcanic aerosol created by the eruption of Mount Pinatubo in 1991 ( Bernard et al. 1991 ), the lidar measurements extended well into the stratosphere ( Post et al. 1996 ), thus providing a unique opportunity to observe the detailed

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Stanley G. Benjamin, Brian D. Jamison, William R. Moninger, Susan R. Sahm, Barry E. Schwartz, and Thomas W. Schlatter

observation types over both summer and winter experiment periods, and for three fields—wind, temperature, and moisture. Other previous work on effects of high-frequency (hourly) observations on short-range forecasts include those reported by Smith et al. (2007) for GPS precipitable water observations and Weygandt et al. (2004) for simulated lidar wind observations [a regional observing system simulation experiment (OSSE)]. The observation sensitivity experiments reported here were carried out

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Patrick Minnis, Edwin F. Harrison, and Patrick W. Heck

(Sassen et al.1990), however, were probably obscured by cirrusclouds since the satellite retrievals indicate only highclouds at that time. It is not clear from these results whether the uncertainties in the satellite analysis of total cloud heigb4sare due primarily to sampling differences in the satellites and lidars or to partially cloud-filled pixel effects.More detailed logs of visual observations would behelpful in determining when low or midlevel cloudswere in the vicinity of the lidar sites

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L. Cucurull, R. Li, and T. R. Peevey

1. Introduction To quantitatively evaluate the benefits of new observations in our understanding and prediction of Earth’s atmosphere, both observing system experiments (OSEs) and observing system simulation experiments (OSSEs) are necessary. OSEs are data-denial studies that allow the evaluation of existing data but cannot be used to analyze the impact of future observing systems. Atmospheric OSSEs are modeling experiments used to perform an objective evaluation of the potential benefits of

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S. W. Dorsi, M. D. Shupe, P. O. G. Persson, D. E. Kingsmill, and L. M. Avallone

mean horizontal wavelength of ~9.7 km ( σ = 1.1 km, n = 9); this is near the theoretically trapped wavelengths from either bracketing sounding. Both radar and lidar profiles ( Fig. 7 ) show signatures of this lee-wave pattern downstream of the ridge axis. Fig . 6. Vertical wind statistics (a) shown as a function of E–W distance from mean ridge axis for 9 transects at 4200 m performed on 9 Jan 2011. Observations are grouped into 1-km-wide E–W bins. The boxes show the interquartile range (IQR

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Zhian Sun and Lawrie Rikus

schemes and their effect on the optical properties determined using the four ice optical parameterizations. As mentioned in the previous section, the cloud water content in GASP is determined by a temperature-dependent diagnostic scheme developed on the basis of several aircraft observations. Recently, Wang and Sassen (2002) presented a new relationship between IWC and temperature determined from 4 yr (1997–2000) of lidar–radar observations collected on the Southern Great Plains in Oklahoma, at the

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David A. Rahn, Thomas R. Parish, and David Leon

zonal heading. Individual soundings and lidar images reveal the complex nature of the lower atmosphere in the SBC, but the discussion will begin with a representation of the mean conditions in the SBC. An average zonal cross section is created from all 90 vertical profiles (individual ascents and descents) taken within the SBC ( Fig. 9a ). Observations are linearly interpolated onto a regular grid and smoothed. Even with 90 individual soundings, there are sampling issues with constructing the mean

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