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Taneil Uttal, Janet M. Intrieri, Wynn L. Eberhard, Eugene E. Clothiaux, and Thomas P. Ackerman

estimates of frequency of occurrence and amount of upper level clouds from observations at ground stations and ship-borne stations. Atmos. Oceanic Phys., 28 (5), 367-377. --, and , 1993: On the climatology of upper-layer 'clouds. J. Climate, 6, 1812-1821.Pal, S. R., W. Steinbrecht, and A. I. Carswell, 1992: Automated method for lidar determination of cloud base height and vertical extent. Appl. Opt., 31, 1488-1494.Parango, F., J. F. Boatman, H. Siervering, S

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J. M. Intrieri, W. L. Eberhard, T. Uttal, J. A. Shaw, J. B. Snider, Y. Han, B. W. Orr, and S. Y. Matrosov

instance, compared to longerwavelength radars, the signal from ground clutter is notas strong, thereby allowing observations within 100 mor so of the radar. At the same time, 8-mm radars willreadily penetrate optically thick clouds, allowing thedetection of cirrus clouds that are above layers of liquidwater and/or precipitation that would attenuate the signal from lidars or shorter wavelength radars. The radar dwell times for the FIRE II project werethree seconds, which represented a good

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Robert M. Banta, Lisa D. Olivier, and David H. Levinson

preliminary results ofthe experiment were described by Intrieri et al. (1990).Figure 1 shows the surrounding terrain and locationof the sensors. In addition to the instrumentation deployed over land, a ship, the R/V Silver Prince, servedas a platform for surface observations and rawinsondeascents during daylight hours on eight weekdays duringLASBEX. As discussed in section 1, the experimentfeatured two kinds of remote sensing instruments,WPL's Doppler lidar and an array of Doppler sodars.To supplement the

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Zhien Wang and Kenneth Sassen

derived from the Raman channel in the lower cloud portion and/or with the constraint of total optical depth ( Young 1995 ). To improve the signal-to-noise ratio of the lidar signal, a 10-min sliding average is applied to the Raman lidar data. The effect of multiple scattering on σ retrieval is not considered in this study, and this may cause the underestimation of visible cloud optical depth ( τ ) and average σ. However, we consider this effect as not very significant for high cloud observations

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C. M. R. Platt, R. T. Austin, S. A. Young, and A. J. Heymsfield

before the start of the monsoon season (e.g., Keenan et al. 1990 , 1994 , 2000 ). In this paper, we describe light detecting and ranging (lidar) and infrared radiometer observations on four storm anvils that were advected over the observational site. The experiment also included various radars ( Sekelsky et al. 1999 ) and a microwave radiometer that measured water vapor path and liquid water path. In Part I of this article, Platt et al. (2002 , hereafter Part I) describe the properties of

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H. Eisele, H. E. Scheel, R. Sladkovic, and T. Trickl

. However, due to the high costs, flight operations are limited to case studies and will not easily permit a dense coverage of stratosphere–troposphere exchange. At IFU, intensified observations of stratosphere–troposphere ozone transfer were started in January 1996, using the second-generation stationary lidar completed in 1995. The efforts have been carried out within the VOTALP (Vertical Ozone Transport in the Alps) project funded by the European Union. To establish such a work package within an

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A. H. Manson

(Vincent 1984; Chanin and Hauchcorne1981; Manson and Meek 1990). Rocket data generally have no (or uncertain) periods (e.g.,Philbrick et al. 1983). Finally, observed Xz (109) from 34 days in summer and winter 1981-86from lidar observations (observed period) are shown with toning (Gardner and Voelz 1987 ).measured lidar )tz of small value agree with the smallestXz from the less direct radar technique, suggesting thatthe two techniques are complementary. It should also be noted that the Urbana group

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Kenneth Sassen, Zhien Wang, C. M. R. Platt, and Jennifer M. Comstock

, U. , and E. Roeckner , 1995 : Influence of cirrus cloud radiative forcing on climate and climate sensitivity in a general circulation model. J. Geophys. Res. , 100 , 16305 – 16323 . Mitchell , D. L. , 2002 : Effective diameter in radiative transfer: General definition, applications, and limitations. J. Atmos. Sci. , 59 , 2330 – 2346 . Platt , C. M. R. , 1973 : Lidar and radiometric observations of cirrus clouds. J. Atmos. Sci. , 30 , 1191 – 1204 . Platt , C. M. R. , and

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Kenneth Sassen, Likun Wang, David O’C. Starr, Jennifer M. Comstock, and Markus Quante

with height was related to directional shear, as was earlier proposed by Oddie (1959) . Observations by Yagi (1969) located the cirrus uncinus head in a turbulent layer with a dry adiabatic lapse rate, which allowed for its more convective appearance, while the fall streaks were situated in the stable layer below. From more recent aircraft, lidar, and radar studies, we know that a variety of structures (i.e., cloud microphysical inhomogeneities) occur in cirrus clouds on both the cloud scale

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Robin J. Hogan

a is the radius of the particle ( van de Hulst 1957 ; Hogan 2006 , hereafter H06 ). For typical ground-based lidar observations of ice and liquid clouds and spaceborne lidar observations of ice clouds and aerosols, the field of view is such that these small-angle forward-scattered photons may remain within the field of view of the detector and contribute to the apparent backscatter, whereas photons that experience wide-angle scattering will typically be transported outside the field of view

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