1 / 6

The Ozone Shield

The Ozone Shield. Atmosphere and Climate Change Chapter Thirteen Section Two. The Ozone Shield. Ozone layer – part of stratosphere where ozone is concentrated Absorbs most of the harmful ultraviolet (UV) rays from the sun UV rays damage genetic material

randilyn-garcia
Download Presentation

The Ozone Shield

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Ozone Shield Atmosphere and Climate Change Chapter Thirteen Section Two

  2. The Ozone Shield • Ozone layer – part of stratosphere where ozone is concentrated • Absorbs most of the harmful ultraviolet (UV) rays from the sun • UV rays damage genetic material • Ozone layer being damaged by chlorofluorocarbons or CFCs

  3. Chlorofluorocarbons • Nonpoisonous, nonflammable, noncorrosive • Used as coolant in freezers and AC, to make plastic, in spray cans & pesticides • Stable at Earth’s surface • In stratosphere, CFCs broken apart by UV rays • Parts of CFC destroys protective ozone layer

  4. The Ozone Hole • Thinning of stratosphere that occurs over the poles in the spring • In 1985, studies showed the ozone layer over the South Pole had thinned by over 50% • Polar stratospheric clouds make air very cold which leads to breakdown of CFC • When sun returns, energy drives destruction of Ozone

  5. Effects of Ozone Thinning • On Humans – As ozone decreases, UV rays reaching Earth increases • UV rays damage DNA in humans • On Animals & Plants – high UV rays can kill phytoplankton, harm amphibians, interfere with photosynthesis

  6. Protecting the Ozone Layer • 1985 Montreal Protocol led to agreement to limit CFCs • In 1995, developed nations pledged to ban CFCs completely • CFC use has dropped dramatically from over 1,000 millions tons per year to less than 200 million tons per year • CFCs stay in stratosphere 60 to 120 years

More Related