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Xiaodong Liu, Shouguo Ding, Lei Bi, and Ping Yang

1. Introduction Ice clouds remain one of the key uncertainty sources in the study of the atmospheric radiation budget and atmospheric remote sensing ( Liou 1986 ; Lynch et al. 2002 ; Wendisch et al. 2007 ; Minnis et al. 1993a , b ; Baum et al. 2000 , 2005 ; Baran 2009 , and references cited therein). These clouds also pose a challenge to atmospheric radiative transfer and remote sensing studies. As the optical properties of ice crystals are fundamental to quantifying the radiative

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Geoffrey E. Hill

frequencyof vibration varies according to the mass of ice collected on it. The vibrating-wire system is designed to beplaced in the humidity duct of VIZ type radiosondes. Supercooled clouds were generated by injecting steam into a cold room. Measurements were made using arotating arm to generate velocities comparable to rising radiosonde balloons. Supercooled liquid water concentrations found from the vibrating-wire measurements were compared with a standard measurement based upona high speed rotating

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Peter G. Black, Russell L. Elsberry, Lynn K. Shay, Ray P. Partridge, and Jeffrey D. Hawkins

, from an Air Force we-130 aircrat~during a regularly scheduled hurricane reconnaissancemission. The deployment strategy involved a 48 h notification to the Air Force of intent-to-drop accompanied by estimated storm and drop locations. These positions were followed by updates at 24 h before drop,at preflight briefing time and in flight after the firstreconnaissance fix position was obtained during thebuoy drop flight. Ten hours after the buoy deployment,a hurricane planetary boundary layer experiment

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Bok-Haeng Heo, Sandra Jacoby-Koaly, Kyung-Eak Kim, Bernard Campistron, Bruno Benech, and Eun-Sil Jung

layer called the entrainment zone is characterized by a significant vertical gradient of virtual potential temperature and a minimum heat flux. According to Stull (1988) , the CBL height is the top of mixed layer, often defined as the average base of the overlying stable layer, and responds to surface forcings with a timescale of about an hour or less. Different definitions of CBL height have been proposed based on various physical quantities. Sullivan et al. (1998) defines Z i as the height

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R. Giles Harrison, Keri A. Nicoll, Douglas J. Tilley, Graeme J. Marlton, Stefan Chindea, Gavin P. Dingley, Pejman Iravani, David J. Cleaver, Jonathan L. du Bois, and David Brus

1853 ; Russell 1922 ; Davis 1964 ). Formally, the net droplet–droplet force is always attractive at small separations regardless of the droplets’ relative polarities, unless the exact ratios of their charges would make them an equipotential on contact ( Lekner 2012 ; Banerjee and Levy 2015 ). With natural variability, this unique equipotential condition is unlikely to occur, hence two colliding charged cloud droplets can be generally considered as being more likely to coalesce than two neutral

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B. A. Gardiner and J. Hallett

. Cooper, 1980: Conduct of cloud spectra measurements. Scientific Report I to the Air Force Geophysics Laboratory, Contract No. AFGL-TR-79-0251. -- and ,1981: Conduct of cloud spectra measurements. ~:inal Report to the Air Force Geophysics Laboratory, Contract No. AFGL-TR-81-0122.

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Victor D. Lupi and R. John Hansman

AUGUST 1991 VICTOR D. LUPI AND R. JOHN HANSMAN 541Development and Testing of the MIT Acoustic Levitation Test Facilities VICTOR D. LUPI AND R. JOHN HANSMANMassachusetts Institute of Technology, Cambridge, Massachusetts(Manuscript received 30 April 1990, in final form 9 December 1990)ABSTRACT Two acoustic levitation test facilities have been developed for cloud physics experimentation. These facilitiesutilize

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Barry B. Hinton and Donald P. Wylie

because windspeed is a scalar quantity that is constrained to zero or positive values. Therefore, observations tend to overestimatethe light winds because of the one-sided distribution of errors, but the bias disappears under stronger winds. Amethod for removing this bias from ship data is presented. In particular, the method is applied to interpretingthe ratios of wind speeds ~observed by ships to those obtained from tracking low level clouds. Corrected ratiosallow low cloud speeds to serve as proxy

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Richard W. Gould Jr., Dong S. Ko, Sherwin D. Ladner, T. Adam Lawson, and Clinton P. MacDonald

saturate over clouds (six bands for SeaWiFS, three for MODIS, and five for VIIRS). Thus, PAR values will be estimated for both clear and cloudy pixels. c. Atmospheric models Gridded solar radiation fields used to force ocean hydrodynamic models are typically provided by numerical weather prediction products ( Wallcraft et al. 2008 ). For example, for NCOM, the solar radiation can come from NOGAPS, COAMPS, or NAVGEM. These atmospheric models calculate Q SW through radiative transfer calculations, and

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Qin Xu, Chong-Jian Qiu, and Jin-Xiang Yu

-altitude horizontal windfield from single-Doppler radial wind data measured during the Phoenix It field experiment. Since the extendedmethod uses only the radial momentum equation on a low-altitude horizontal plane with a weak nondivergenceconstraint for the horizontal winds, the pressure gradient and vertical advection are treated as an unknownresidual forcing. The test results show that (i) the method can retrieve the low-altitude time-mean (or runningmean) horizontal winds (averaged over a period of several

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