Rain, Snow and More: Phases of Atmospheric Water (page 2)
Get the Facts
- Precipitation formed in clouds with temperatures above freezing is called warm precipitation. If ice is involved at some stage in the production, the precipitation is called cold precipitation. For more information about warm and cold precipitation, see "precipitation" in Grolier Multimedia, Encarta, or other CD-ROM encyclopedias.
- Weather modification is the changing of the atmospheric environment in some artificial way. Artificial rainmaking is accomplished by cloud seeding, which is the artificial addition of condensation nuclei to clouds. Find out more about cloud seeding. What are clouds seeded with? See Frank H. Forrester, 1001 Questions Answered about the Weather (New York: Dover Publications, 1981), pp. 358-359.
- Drizzle is drops of liquid water with a diameter less than 0.02 inches (0.005 cm). Find out more about liquid precipitation. What is the size of raindrops? What is the difference between light, moderate, and heavy drizzle? How do light, moderate, and heavy rain compare? For information, see Jack Williams, The Weather Book (New York: Vintage Books, 1992), p. 73.
- Rime is ice formed when tiny drops of water rapidly freeze on contact with a surface. Hexagonal-shaped snowflakes form as water vapor sublimes (changes from a gas to a solid) on the surface of crystals. Are there any snowflakes that are alike? What is graupel? How do hailstones form? How do atmospheric conditions affect the formation of frozen precipitation? For information, see The Weather Book, pp. 95–105.
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