Presentation on theme: "Ozone & Greenhouse Effect. What is Ozone? Ozone is a molecule that occurs in the Stratosphere Ozone absorbs harmful UV rays from the sun O 3 + uv O 2."— Presentation transcript:
What is Ozone? Ozone is a molecule that occurs in the Stratosphere Ozone absorbs harmful UV rays from the sun O 3 + uv O 2 + O O 3 Ozone in the stratosphere protects us from harmful UV radiation
What’s the problem? In the 1970’s a compound called Chlorofluorocarbons (CFC’s) began to be used. CFC’s were used in refrigerators, propellants, aerosols, etc. It was thought that CFC’s were inert until scientists discovered…
Dangers of Ozone Depletion When ozone is depleted, harmful uv rays can get through the atmosphere This makes it much easier to get skin cancer
What has been done? Once it was proven that CFC’s were destroying ozone, scientists met in Montreal and made the Montreal Protocol The Montreal Protocol called for a ban of CFC’s and that production of CFC’s be stopped
The Greenhouse Effect Sun’s energy (aka- heat) gets trapped in the troposphere Some radiation that reaches Earth’s surface is absorbed. Some energy is reflected.
The Greenhouse Effect Reflected heat might get trapped by carbon dioxide, water vapor, or other gases. Trapped heat makes atmosphere warmer. Warm atmosphere reflects heat to Earth’s surface again!
Greenhouse Effect No greenhouse effect would mean colder than average temps. Too much, however, can cause a rise in average temps.
Global Warming Global warming IS the rise in average temps. Melting ice caps, rising seas, droughts
Global Warming Probable cause: carbon dioxide Where does it come from? Burning of fossil fuels (coal, oil, natural gas)
Greenhouse Gases The three types of greenhouse gases are water vapor, carbon dioxide and methane. They absorb heat energy from the sun in the form of infrared radiation. This keeps the earth warm enough for life to exist.