Page 193 - Geosystems An Introduction to Physical Geography 4th Canadian Edition

6.1b
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Cross Section of Atmospheric Circulation The cross section shows the relationship between pressure cells (rising or sinking air) and the circulation cells and winds.
Stratosphere
Arctic tropopause
Midlatitude tropopause
Tropical tropopause
Subtropical jet stream
Trade winds
Polar high
Polar jet stream
Westerlies
90°
Polar circulation
60°
50°
Midlatitude circulation
40° 30° 20° H
Western Ghats in dry season
10° 0° L
[Arne Huckelheim.]
Polar easterlies
Subtropical high
Equatorial low
6.2
Hadley cell
GEOquiz
PRECIPITATION PATTERNS AND ATMOSPHERIC CIRCULATION
Areas of higher precipitation in green, yellow, and orange are zones of low pressure and moist, rising air. Areas of lower precipitation, shown in white on the maps, are zones of high pressure, where air sinks and dries out. Notice the band of heavy rainfall along the ITCZ, and how areas of dryness and moisture vary seasonally on both maps
TRMM image (Tropical Rainfall Measuring Mission) [GSFC/NASA].
Western Ghats in rainy season
Equator
Band of precipitation indicates the ITCZ
Equator
Explain: What causes the difference in precipitation between the dry and rainy seasons in the Western Ghats mountain range of India.
Thunderstorms on the Brazilian horizon as seen from the International Space Station [NASA].
Western Ghats
Western Ghats
1. Explain: The position of subtropical highs and subpolar lows shifts with the seasons. Explain how this shift affects climate patterns of the midlatitudes.
2. Compare: Describe surface air movements where a Hadley cell meets a midlatitude cell and where two Hadley cells meet the ITCZ. How do these movements explain the climate patterns along these boundaries?
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geosystems in action 6ATmoSPHeriC CirCuLATioN
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