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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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Mark Smalley, Kay Sušelj, Matthew Lebsock, and Joao Teixeira

the MERRA2 subsidence at 500 hPa is stronger than 1 hPa h −1 . Fig . 1. (a) The MAGIC polygon study region (orange bounds) and the frequency of all scenes that a given area has its highest cloud top below 2 km, as reported by the CloudSat 2B-GEOPROF-lidar Layer_Top, for June–July–August 2007. (b) Average vertically resolved cloud fraction across the MAGIC polygon outlined in (a) derived from the merged CloudSat and CALIPSO observations described in section 3c . c. Observations for

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Philippe Lopez and Peter Bauer

Measuring Mission (TRMM), Aqua , and Moderate Resolution Imaging Spectroradiometer. More is expected from the recently launched CloudSat and from future missions such as the Global Precipitation Mission (2010–12). All these observations consist of either direct measurements of multifrequency radiances [mainly in the microwave (MW) and infrared bands], radar reflectivities, or lidar backscattering cross sections, or retrieved quantities (e.g., optical depth and rain rates). Ground-based measurements are

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