1. Circulation Cells
Mr. Silva
Ag Earth Science

2. Air Circulation Cells Preview
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3. Hadley Air Circulation Cells
• Circulation of hot air near the equator
• Air is heated, rises and spreads north and
south toward subtropics.
• Subtropic air replaces hot tropical
air...process starts again
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4. Hadley Air Circulation Cells
• high humidity
• high clouds
• heavy rains/precipitation
• No winter!!!
• Temperature change greater from day to
night than from season to season.
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5. Ferrel Air Circulation Cells
• Ferrel cells develop between 30* and 60*
north and south latitudes.
• Great seasonal fluctuation of temperature.
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6. Ferrel Air Circulation Cells
• Distinct winter season
• Usually has broadleaf deciduous and
evergreen coniferous forest
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7. Polar Air Circulation Cells
• Icy-cold, dry, dense air descends from the
troposphere
• Meets warmer air at mid latitudes and
then returns to the poles cooling and
sinking
• Sinking air suppresses precipitation, thus
polar regions are deserts
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8. Polar Air Circulation Cells
• Low temperatures
• severe winters
• small amounts of precipitation
• Two biomes:
– tundra
– taiga
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9. Air Circulation Cells Review
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10. Hurricanes, Cyclones, and
Tornadoes, Oh My!
• Hurricanes are the most severe weather
phenomenon on the planet...cyclonic
circulation of air, thunderstorms, and rain
• Tornadoes are swirling masses of air with
wind speeds of 300mph that happen over
land.
• Cyclones are larger than tornadoes,
happen over water and last several days.
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11. Tornadoes
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12. Hadley Air Circulation Cells
• Circulation of hot air near the equator
• Air is heated, rises and spreads north and
south toward subtropics.
• Subtropic air replaces hot tropical
air...process starts again
• Hadley cells characterized by high
humidity, high clouds, and heavy rains
• No winter!!! Temperature change greater
from day to night than from season to12
season.

13. Coriolis Effect
• Uneven heating of the Earth’s surface
– caused by the Earth’s axis, rotation, and
revolution around the sun.
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