The Ozone Layer

Area in the stratosphere where ozone is highly concentrated.

Absorbs most of the UV (ultraviolet) light from the sun

"is like sunscreen for the Earth"

a molecule made of three oxygen atoms

a colorless gas

Good Ozone - ozone in the stratosphere that protects human health and the environment

Bad Ozone - ground-level ozone which is a respiratory irritant (emissions mixed with heat and sunlight)

Humans - damages DNA, causes skin cancer

Plants - interferes with photosynthesis

Animals - kills eggs (off springs)

1985 - Vienna Convention for the Protection of the Ozone Layer

1987 - Montreal Protocol - nations agreed to sharply limit their production of CFCs

1992 - Copenhagen, Denmark - developed countries agreed to eliminate most CFCs by 1995

US pledged to ban all substances that pose significant danger to ozone by 2000

CFC molecules remain active in the stratosphere for 60 to 120 years

CFCs released 30 years ago are still destroying the ozone today

CFCs released from leaky air conditions still exist

Many years will be needed before the ozone layer completely recovers.

Global warming (climate change) and ozone layer depletion are two different problems.

Global warming is caused by the "greenhouse effect", while ozone depletion is caused by "ultraviolet (UV) rays"