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Lynette van Schalkwyk and Liesl L. Dyson

1. Introduction The reduced ceiling and horizontal visibility associated with fog is of particular importance for the aviation industry. Safety is a considerable concern to the aviation community and accidents often occur in reduced visibility conditions ( Tardif and Rasmussen 2007 ). According to the International Civil Aviation Organization (ICAO), takeoff and landing of aircraft under visual flight rules (VFR) is not allowed when the visibility is less than 5000 m and the cloud-base height

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J. E. Jiusto, R. J. Pilié, and W. C. Kocmond

$60 JOURNAL OF APPLIED METEOROLOGY Vo~.v,~l~ 7Fog Modification with Giant Hygroscopic NucleP J. E. J~usTo~, R. J. PI~.~ xx*n W. C. Koc~ot~'n Corndl Aerona#li~al Laboraloty, I~zc., Bu~alo, N. Y. (Manuscript received 13 February 1968~ iu revised form 22 May 1968) ABSTRACT Analytic and experimental investigations were conducted to examine the concept of modifying fog withhygroscopic

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Li Yi, King-Fai Li, Xianyao Chen, and Ka-Kit Tung

be navigable by open-water vessels and the central Arctic will be navigable for moderate icebreakers. The increasing occurrence of fog and low stratus discussed above would greatly reduce the visibility and pose danger to aviation and shipping activities in the Arctic region ( Koračin et al. 2014 ). Historical Arctic fog and low stratus reports rely on surface observations that are widely distributed over the Eurasian continent, and are significantly less over North America and the Arctic Ocean

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116MONTHLY WEATHER REVIEW Vol. 97, No. 2UDC 551.575.2:551.c$2.2(73)HEAVY-FOG REGIONS IN THE CONTERMINOUS UNITED STATES'ROBERT L. PEACE, JR.Cornell Aeronautical Laborafory, Inc., Buffalo, N.Y.2ABSTRACT The heavy-fog statistics for 256 first-order weather stations were utilized to update analyses of the geographicdistribution of fog within the conterminous United States. The survey shows that heavy fog (visibility one-fourthmile or less) occurs more than 20 days a year at approximately 50

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Michael B. Meyer and G. Garland Lala

MAY1990 MICHAEL B. MEYER AND G. GARLAND LALA 577Climatological Aspects of Radiation Fog Occurrence at Albany, New York MICHAEL B. MEYER AND G. GARLAND LALAAtmospheric Sciences Research Center, State University of New York at Albany, Albany, New York(Manuscript received 6 September 1988, in final form 28 November 1989)ABSTRACT We present a detailed investigation of the local radiation fog climatology

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I. Gultepe, T. Kuhn, M. Pavolonis, C. Calvert, J. Gurka, A. J. Heymsfield, P. S. K. Liu, B. Zhou, R. Ware, B. Ferrier, J. Milbrandt, and B. Bernstein

Increased understanding of ice fog microphysics can improve frost and ice fog prediction using forecast models and remote-sensing retrievals, thereby reducing potential hazards to aviation. Ice fog occurs usually at temperatures less than −15°C because of direct deposition of water vapor into ice nuclei. It significantly affects aviation and transportation in northern latitudes because ice fog causes low visibilities and ice crystal accumulation on the surface of structures. Ice fog may also be

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E. K. Biggs, J. L. Brownscombe, and W. J. Thompson

FEBRUARY 1969 BIGG, BROWNSCOMBE AND THOMPSON 75Fog Modification with Long-Chain AlcoholsE. K. BIGG, J. L. BROWSSCOaBV. ^~m W. J. Taom, soN Radiophysics Laboratory, CSIRO, Sydney, Australia(Manuscript received 20 August 1968, in revised form 25 October 1968) ABSTRACT The growth of water drops on condensation nuclei in a supersaturated environment can be greatly

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March 1971221UDC 651.509.615:551.574.1NUMERICAL EXPERIMENTS PERTAINING TO WARM-FOG CLEARING L. RANDALL KOENIGThe Rand Corporation, Santa Monica, Calif.ABSTRACTAn at,tempt has been made quantitatively to assess the prospects for modifying warm fogs by seeding them withcondensation nuclei. This has been done by calculating the time-dependent changes in the sizes and concentrations offog droplets that are predicted by the ordinary equations of diffusion of water vapor to and from the surface of

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R. J. Pilié, E. J. Mack, W. C. Kocmond, C. W. Rogers, and W. J. Eadie

APRil. 1975 R.J. PILI~; ET AL. 347The Life Cycle of Valley Fog. Part I: Micrometeorological Characteristics~R. J. PxL~~, E. J. MACK, W. C. KOCMOND, C. W. ROGERS AND W. J. EADIECalspan Corporation, Bu. ffalo, N, -. 14221(Manuscript received 20 August 1973, in revised form 8 October 1974)ABSTRACT Extensive measurements were made of mierometeorological variables associated with

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Daisuke Kuroiwa

JUNE 1951DAISUKE KUROIWA157ELECTRON-MICROSGOPE STUDY OF FOG NUCLEI By Doisuke Kuroiwce Hokkaido University, Sapporo(Manuscript received 26 February 1951)ABSTRACTSea-fog nuclei were examined by means of an electron microscope. The observations were made on theevaporation residues of fog particles. 32 fog particles were examined, and it was found that 11 of them hadhygroscopic nuclei, 16 had non-hygroscopic nuclei, and 5 had no nucleus. The average maximum extent ofthe nuclei was found to be

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