. Compendium of meteorology. Meteorology. Fig. 3.—The effect of acetone vapor on the crystal habit of snow, (a) Effect of 1 molecule of acetone to 10 molecules of water. (6) Effect of 1 molecule of acetone to 100 molecules of water, (c) Effect of 1 molecule of acetone to 1000 molecules of water. subsequent study. Samples have now been obtained by this method in most parts of the world as well as at high altitudes in the atmosphere during flight studies with Project Cirrus airplanes. Figure 5 shows some of these replicas. A more recent technique for making replicas utilizes a plastic spray.' Al
. Compendium of meteorology. Meteorology. Fig. 3.—The effect of acetone vapor on the crystal habit of snow, (a) Effect of 1 molecule of acetone to 10 molecules of water. (6) Effect of 1 molecule of acetone to 100 molecules of water, (c) Effect of 1 molecule of acetone to 1000 molecules of water. subsequent study. Samples have now been obtained by this method in most parts of the world as well as at high altitudes in the atmosphere during flight studies with Project Cirrus airplanes. Figure 5 shows some of these replicas. A more recent technique for making replicas utilizes a plastic spray.' Although the solvent used in this 1. Such as Kr}'lon, made by Foster & Kester, Philadelphia, or Plastic Spraj', made by the Bridgeport Brass Co., Bridge- port, Conn spray would not work under normal conditions, since it would tend to dissolve the ice structure, its evapora- tion is so rapid that satisfactory replicas are obtainable if brief applications are made. This technique works best if the spray container is cooled below OC. How- ever, if the spraying is carried out in air at temperatures below freezing, enough entrainment of cold air takes place so that good replicas have been made at —IOC with the dispenser temperature at 25C. Solid Precipitation in the Free Atmosphere Precipitation in the form of snow crystals, graupel, sleet, or hail forms under varied conditions of tempera- ture, humidity, and turbulence, and in the presence of a variety of suitable nuclei to be described later. The. Fig. 4.—Typical replica of a stellar snow crystal. moisture content of the air in which such precipitation may form at temperatures below OC range from more than 3 g m~^ in supercooled water-droplet clouds to such small amounts that the air contains no visible cloud, although it is supersaturated with respect to ice. Ice Crystals in Cirrus Clouds. The highest clouds commonly found throughout the world are the cirrus types. Evidence is accumulating suggesting that most clouds of t
Size: 1476px × 1693px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodivers, booksubjectmeteorology
