Page 241 - Geosystems An Introduction to Physical Geography 4th Canadian Edition

Chapter 7 Water and Atmospheric Moisture 205
16. Specifically, what is a cloud? Describe the droplets that form a cloud.
17. Explain the condensation process: What are the requirements? What two principal processes are dis­ cussed in this chapter?
18. Whatarethebasicformsofclouds?UsingTable7.1, describe how the basic cloud forms vary with altitude.
19. Explainhowcloudsmightbeusedasindicatorsofthe conditions of the atmosphere and of expected weather.
20. What type of cloud is fog? List and define the princi­
pal types of fog.
21. Describe the occurrence of fog in Canada and the United States. Where are the regions of highest incidence?
Answer to Critical Thinking 7.3: The river water is warmer than the cold overlying air, producing an evapo­ ration fog, especially beyond the bend in the river. The moist farmlands have radiatively cooled overnight, chilling the air along the surface to the dew point, re­ sulting in active condensation. Wisps of radiation fog reveal the flow of light air movements from right to left in the photo.
looking for additional review and test prep materials? Visit the Study Area in MasteringGeographyTM to enhance your geographic literacy, spatial reasoning skills, and understanding of this chapter’s content by accessing a variety of resources, including interactive maps, geoscience animations, satellite loops, author notebooks, videos, RSS feeds, web links, self-study quizzes, and an eText version of Geosystems.
visualanalysis 7 What type of fog is this?
What type of fog is this? The scene is at about 80° north latitude, and in the background is the Austfonna Ice Cap on Nordaustlandet Island, part of the Svalbard Archipelago. Walrus moms and pups gather in a haul out on a rocky unmapped islet, ex­ posed by recent ice retreat. As air colder than the 0°C ocean descends off the ice cap near the coast, evaporation humidifies this air layer. Away from the coast, conditions are clear.
1. As air drains off the ice cap, colder than the 0°C ocean temperature, describe the process underway that is producing the fog. How is the air humidified?
2. What type of fog has formed in the photo?
3. Why are conditions clear farther from the coast? Consider the relationships between humidity, air temperatures, and dew-point temperatures near the ice and farther away from it.
[Bobbé Christopherson.]