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P. R. Field, A. J. Heymsfield, and A. Bansemer

of Tropical Anvils and Cirrus Layers-Florida Area Cirrus Experiment (CRYSTAL-FACE), Convection and Moisture Experiment (CAMEX), Tropical Rainfall Measuring Mission (TRMM), and First International Satellite Cloud Climatology (ISCCP) Regional Experiment (FIRE). Table 1 gives a summary of the aircraft/probe combinations used. The CRYSTAL-FACE and TRMM flights were both in thick anvil ice clouds associated with tropical convection with in-cloud temperatures ranging from −12° to −5° and −50° to −15

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Paul R. Field

1. Introduction Understanding the evolution of the ice phase in clouds is necessary if advances are to be made in the study of precipitation, which plays a large role in controlling the distribution of water within the troposphere. It was not until the advent of aircraft observations that it became possible to follow the evolution of ice crystal size spectra in frontal clouds and hence investigate the processes responsible for the production of precipitation in those clouds (e.g., Passarelli

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Hyun Youk, Roland List, and Theophilus Ola

1. Introduction The growth of an atmospheric ice crystal is determined by its heat and mass transfer. They are characterized by dimensionless numbers, the Nusselt number (Nu) for heat and the Sherwood number (Sh) for mass transfer. Both numbers are functions of the airflow as described by the dimensionless Reynolds number (Re = υDρη −1 ), where υ is the relative air velocity, D the diameter, ρ is the density of the fluid (air), and η the dynamic viscosity of the fluid). For pure

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William J. Eadie and Thomas R. Mee

260 JOURNAL OF APPLIED METEOROLOGY VOLU~aE 2The Effect of Dry-Ice Pellet Velocity on the Generation of Ice Crystals~ WILtIA~ J. E~i~- A,XrO T~O~AS R. MEECorndl Aeronautical Laboratory, Inc., of Corndl University (Manuscript received 21 September 1962) The influence of fall velocities of dry-ice pellets on the nucleation of slightly supercooled clouds is discussed and the conditions necessary for the

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L. Levi and F. Prodi

NOVEMBER 1978 L. L E V I A N D F. P R O D I 2181Crystal Size in Ice Grown by Droplet Accretion L. LEvi~ AND F. PRODIIFA-CNR, Se~ione Nubi e Precipitazioni, Bologna, Italy(Manuscript received 17 May 1978, in final form 21 August 1978)ABSTRACT The size of crystal grains in ice formed by accretion of supercooled droplets has been determined for awide range of air (--11 to --25-C) and deposit (0 to --16

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Trevor J. McDougall, Paul M. Barker, Rainer Feistel, and Ben K. Galton-Fenzi

the brine apply up to an Absolute Salinity of 120 g kg −1 [see section 2.6 of IOC et al. (2010) ]. The upwelling of very cold seawater (colder than the surface freezing temperature) can lead to supercooling and the formation of small ice crystals called frazil ice, and this process is also examined using the TEOS-10 Gibbs functions of ice Ih and of seawater. Under the assumption that the relative vertical velocity (the Stokes velocity) of frazil can be ignored, we derive expressions for the rate

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K. Aydin and J. Singh

1. Introduction The classification of ice crystals in clouds using radars is expected to be useful for cloud microphysical studies. Knowing the crystal type in the radar resolution volume will also be helpful in improving the quantitative estimation of cloud ice water content (IWC) with radar ( Aydin and Tang 1997a ). Polarimetric radars at millimeter-wave frequencies, such as 95 GHz, have the potential for classifying ice crystals in clouds. The short wavelength (3.2 mm), compared to S- or C

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Chengzhu Zhang and Jerry Y. Harrington

1. Introduction Ice crystal growth from vapor is an important microphysical process critical for the evolution of atmospheric cold clouds. Unlike liquid drops, ice crystals can grow to precipitation sizes by vapor depositional growth alone. The growth rates of crystals are determined by the particle shape and surface characteristics, which in turn control the particle dimension, ultimately affecting collection and sedimentation processes ( Fukuta and Takahashi 1999 ; Libbrecht 2005 ; Avramov

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H. J. aufm Kampe, H. K. Weickmann, and J. J. Kelly

168 JOURNAL OF METEOROLOGY VOLUME 8THE INFLUENCE OF'TEMPERATURE ON THE SHAPE OF ICECRYSTALS GR WING AT WATER SATURATIONBy He J. aufm Kampe, Eo KO Weickmann aped J'*KellySignal Corps Engineering Laboratories(Manuscript received 19 December 1950) ABSTRACTInvestigations regarding the influence of temperature on the shape of ice crystals, grown at water saturation, were carried out in a room-size cold chamber. It was found that the principal shape of the ice crystalsLe., column- and plate

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Timothy L. Miller and Kenneth C. Young

458 JOURNAL OF THE ATMOSPHERIC SCIENCES VOLUME36A Numerical Simulation of Ice Crystal Growth from the Vapor Phase Tmox~Y L. MIL~.Ea AND KEN~mla C. YOUNGInstitute of Atmospheric Physics, Uni, erslty of Arizona, Ta-son 85721(Manuscript received 12 September 1978, in final form 27 November 1978)ABSTRACT A detailed scheme for numerically integrating the diffusion equation for ice crystal growth is presented

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