The Ozone Problem  O3 O3 O3 O3

 CFC’s Chlorofluorocarbons Chlorofluorocarbons  Methyl bromide  Results More UV radiation More UV radiation Growth & reproduction Growth & reproduction Decrease photosynthesis Decrease photosynthesis

Sulfur Compounds  Self-supporting thermal control system

Atmospheric Motion

Nonrotating Earth  Equator Warming and rising of air Warming and rising of air Rising air cools as it ascends Rising air cools as it ascends Surface winds blow towards equator to replace ascending air Surface winds blow towards equator to replace ascending air  Poles Cool, dry air descends Cool, dry air descends

Effects of Rotation  Coriolis Effect

Coriolis Effect  Coriolis effect is the apparent deflection of objects moving across Earth’s surface The deflection is caused by the differential speed of rotation between Earth’s equator and polar regions, relative to an object moving across the Earth’s surface. The deflection is caused by the differential speed of rotation between Earth’s equator and polar regions, relative to an object moving across the Earth’s surface.

Global Wind Bands  Hadley cells Subtropical cells Subtropical cells Air rises at the equator due to solar heating, and falls due to cooling at ~30º Air rises at the equator due to solar heating, and falls due to cooling at ~30º

Global Wind Bands  Ferrel cells Temperate cells Temperate cells Occurs between 30º and 50-60º latitude Occurs between 30º and 50-60º latitude Some air descending at 30º turns poleward Some air descending at 30º turns poleward

Global Wind Bands  Polar cells Centered over each pole Centered over each pole At 50-60º, the air is warm and wet enough to ascend, but too dense to mix with Ferrel cell At 50-60º, the air is warm and wet enough to ascend, but too dense to mix with Ferrel cell

Wind Patterns  Between Cells: Vertical air movement Vertical air movement Weak surface winds Weak surface winds  Within Cells: Horizontal air movement Horizontal air movement Strong surface winds Strong surface winds

Wind Patterns  Between Cells:  Hadley cells Doldrums Doldrums Near the equatorNear the equator Decrease in pressure gradientDecrease in pressure gradient Variable breezesVariable breezes Intertropical Convergence Zone (ITCZ) Intertropical Convergence Zone (ITCZ)

Wind Patterns  Between Cells:  Hadley and Ferrel cells Horse latitudes Horse latitudes 30º latitude30º latitude Subtropical high pressureSubtropical high pressure Sinking air; drySinking air; dry Many deserts are found at this latitude Many deserts are found at this latitude

Wind Patterns  Within Cells: Hadley cell Hadley cell Trade WindsTrade Winds Easterlies Easterlies Centered at 15ºCentered at 15º Ferrel cell Ferrel cell WesterliesWesterlies Centered at 45ºCentered at 45º Polar cell Polar cell EasterliesEasterlies 60-90º60-90º