Presentation is loading. Please wait.

Presentation is loading. Please wait.

Stratospheric Ozone Absorbs Harmful UV

Similar presentations


Presentation on theme: "Stratospheric Ozone Absorbs Harmful UV"— Presentation transcript:

1 Stratospheric Ozone Absorbs Harmful UV

2 Atmospheric Ozone O3 O3

3 Stratospheric Ozone Absorbs Harmful UV Rays
sunburn causing UV Sunburn effect (as measured by the UV Index) is the product of the sunlight power spectrum (radiation intensity) and the erythemal action spectrum (skin sensitivity) across the range of UV wavelengths.

4 Total amount O3 remains constant
240nm 280nm O2 -> O + O then O + O2 -> O3 O3 -> O2 + O 240nm 280nm Short wavelength UV splits O2, freeing up O to combine with another O2 to make ozone Longer wavelength UV does the opposite, breaking apart ozone molecules

5 Ozone is broken down by Cl/Br that rises into the stratosphere
1 2 Chloro- flourocarbons (CFC’s) are one source of Cl 3 4 5 6

6 Global phase out of CFCs began in 1987…

7 …but the damage to the ozone layer lingers
Predicted complete repair

8 Montreal Protocol 1972 1987 unanimous international agreement to eliminate the use of ozone depleting chemicals CFC phase out by 2000 (developed nations) and 2010 (developing nations) HCFC phase out: 90%n by 2015; 100% by 2030 Arguably the most successful environmental global action in history

9 …puts the planet on the road to restoration
Predicted complete repair by 2050


Download ppt "Stratospheric Ozone Absorbs Harmful UV"

Similar presentations


Ads by Google