Page 315 - Geosystems An Introduction to Physical Geography 4th Canadian Edition

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10.4
AIR PRESSURE
Winds flow from areas of high pressure to areas of low pressure. The equatorial low creates a belt of wet climates. Subtropical highs create areas of dry climates. Pressure patterns influence atmospheric circulation and movement of air masses. Oceanic circulation and multi-year oscillations in pressure and temperature patterns over the oceans also affect weather and climate. (Chapter 6; review Figures 6.10 and GIA 6)
Hadley cell
Atmospheric advection
of water vapour
Cloud formation
Surface trade winds
Surface trade winds
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ITCZ
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Explain: Where are the trade winds on this view of the globe? Explain and locate areas of warm, wet climates and hot, dry climates in relation to the Hadley cells.
Hadley cell
Precipitation
10.5 AIR MASSES
Vast bodies of homogeneous air form over oceanic and continental source regions, taking on the characteristics of their source region. As these air masses migrate, they carry their temperature and moisture conditions to new regions. At fronts, where air masses meet, precipitation or violent weather may occur. (Chapter 8; review Figure 8.1)
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Evaporation
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Cold, dry cA and cP air masses bring stable air and clear skies to central Canada and the Prairie Provinces in winter such as in this scene from Grasslands National Park in Saskatchewan.
[Branimir Gjetvaj / branimirphoto.ca, all rights reserved.]
10.6 ATMOSPHERIC MOISTURE
The hydrologic cycle transfers moisture through
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Earth’s climate system. Within this cycle, the
processes of evaporation, transpiration, condensation, and precipita60ti°on are essential components of weather. (Chapters 7 and 9; review Figure 9.4)
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[cpphotoimages/Shutterstock.]
geosystems in action 10Earth’s ClimatE systEm
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GEOquiz
1. Analyze: How do these six components of Earth’s climate 2. Discuss: Describe the role that each component of the system interact to produce the world climates in Figure 10.2? climate system plays in causing precipitation patterns on
Earth.