1. Global Changes in the Atmosphere
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Global Changes in the Atmosphere
Global Warming
and
Ozone Depletion

2. Global Warming
Over the last 120 years , the average temperature of the troposphere( the layer of the atmosphere closest to Earth) has risen by 0.5° Celsius
Global Warming is the gradual increase in the temperature of Earth’s atmosphere
The Greenhouse Effect is a natural process by which heat is trapped in the atmosphere by water vapor, carbon dioxide, methane and other gases that form a “blanket” around the Earth.

3. Global Warming
The gases that trap solar energy are called greenhouse gases. The greenhouse effect helps life to exist on Earth.
Human activities that add greenhouse gases to the atmosphere may be warming Earth’s atmosphere.
Burning wood, coal, oil, and natural gas adds carbon dioxide to the atmosphere.

4. Ozone Depletion
Ozone is a gas in the stratosphere, a high layer of the atmosphere, that absorbs most of the ultraviolet radiation that strikes Earth from the sun.
Chemicals produced by humans have been damaging the ozone layer, chloroflourocarbons (CFC’s) are the main cause.

5. Ozone Depletion
A decrease of ozone in the stratosphere means more ultraviolet radiation strikes Earth’s surface, and us. Ultraviolet radiation can cause
- sunburns
-eye damage
- skin cancer

6. Melting Glaciers/ Ice Caps

7. Melting Glaciers/ Ice Caps