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Alexander Harrison, Alfred M. Moyle, Marcus Hanson, and Jerry Y. Harrington

1. Introduction The mass growth of ice crystals from the vapor is a key microphysical process, and yet quantifying the impact of ice surface processes on the mass growth rate remains a challenge. The surface processes through which vapor is incorporated into the crystal are not well understood and are typically approximated using growth efficiencies called “deposition coefficients” α . The deposition coefficient describes the fraction of impinging vapor molecules that incorporate into the

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Vaughan T. J. Phillips, Paul J. Demott, Constantin Andronache, Kerri A. Pratt, Kimberly A. Prather, R. Subramanian, and Cynthia Twohy

measurements. For dust, optical probes deployed there provided the data. For carbonaceous material, the data was from the Interagency Monitoring for Protection of Visual Environments (IMPROVE) at Mt. Zirkel nearby. Relative contributions ( α X ) from dust, soot, and insoluble organics to the total IN concentration at SPL were estimated from composition fractions observed during INSPECT and previous field campaigns in the background troposphere. Residual material was collected from ice crystals sampled from

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Paul J. Huffman and William R. Thursby Jr.

SEPTEMBER 1969 PAUL J. HUFFMAN AND WILLIAM R. THURSBY, JR. 1073Light Scattering by Ice CrystalsPAUL J. Hu~rmu~ A~D WILLIAM R. TltlYRSBY, JR.,~ CAPTAIn, USAFAir Force Cambridge Research Laboratories, Bedford, Mass.(Manuscript received 29 April 1969)ABSTRACT The relative scattering functions between 10- and 150- scattering angle have been measured for microscopic ice crystals grown in a laboratory cold chamber. All

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K. O. L. F. Jayaweera

?28 JOURNAL OF THE ATMOSPHERIC SCIENCES VonumE28Calculations of Ice Crystal Growth K. O. L. F. J.~-Aw~.~a,tDi, ision of Radiophysics, CSIRO, Sydney, Australia(Manuscript received 11 November 1969, in revised form 4 November 1970) The growth rates, and the masses to which the crystals grow at different times, are calculated for varioustemperatures using the electrostatic analogy and assuming that the

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R. I. Smith-Johannsen

532 JOURNAL OF THE ATMOSPHERIC SCIENCES VoLuu~;26Ice Crystal Agglomeration: T Formation R. I. Sm'ra-Jo~am~s~.sPhy~s Dtpt., Massa, huse#s I~titut~ of Technology, Cambridg~(Manuscript received 23 January 1969) Numerous agglomerates shaped somewhat like the letter T were observed among replicas of ice crystalscollected from laboratory ice clouds and replicated using the resin vapor technique. In fact, it

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Takeshi Ohtake and Rudolf G. Suchannek

AVmL1970 TAKESHI OHTAKE AND RUDOLF G. SUCHANNEK 289Electric Properties of Ice Fog Crystals TAKESHI OttTAKE1 AND RUDOL~ G. S~JCX-X~NNEXGeophysical Institute, University of Alaska, College, Alaska(Manuscript received 28 April 1969, in revised form 8 December 1969)ABSTRACT Electric properties of ice fog crystals were studied using uniform and nonuniform electric-fields. It wasobserved that natural and artificial

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S. C. Mossop and A. Ono

130 JOURNAL OF THE ATMOSPHERIC SCIENCES VO~.t0ME 26Measurements of Ice Crystal Concentration in Clouds S. C. Mosso~ ANn A. ONoRadlophysics Laboratory, CSIRO, Sydney, Australia (Manuscript received 25 July 1968)ABSTRACT Measurements of ice crystal concentration in five clouds in northern New South Wales are reported.These confirm earlier studies in which it was found that glaciated altostratus clouds

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Benjamin J. Murray, Christoph G. Salzmann, Andrew J. Heymsfield, Steven Dobbie, Ryan R. Neely III, and Christopher J. Cox

Ice crystals with threefold symmetry in the atmosphere may not be made of hexagonal ice. In late 1611, Johannes Kepler was pondering what he should give his friend and patron, Baron Wackher von Wackhenfels, as a New Year’s gift when a snowflake landed on his coat. He was struck with a perfect philosophical present for his patron: why do snowflakes have six corners rather than some other number, say, seven or five? In the pamphlet that Kepler produced as a gift for his friend, he presented the

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T. Kuhn, I. Grishin, and J. J. Sloan

describe a system for imaging of very small ice particles crystals and classifying them automatically with high speed and accuracy. In this report, we first describe a system for imaging very small ice crystals and a method for classifying them automatically with high speed and accuracy. Then, we demonstrate the capabilities of this system in a laboratory study of the early-stage growth of ice particles under precisely controlled conditions in a cryogenic laboratory flow tube. 2. Particle imager a

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August H. Auer Jr.

MARCH1972 AUGUST H. AUER, JR. 311Inferences about Ice I~lucleation from Ice Crystal Observations AvGVST H. AUER, JR.Dept. of Atmospheric Resources, University of Wyoming, Laramie 82070(Manuscript received 23 April 1971, in revised form 1 November 1971)ABSTRACT The total concentration of ice crystals found in natural cap clouds appears to result from the nucleatingbehavior of at least

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