Unit 10: Air Pollution, Climate Change, and Ozone Depletion Chapters 18 and 19.
Ozone Depletion & Water Pollution
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Transcript of Ozone Depletion & Water Pollution
Ozone Depletion & Water Pollution
Unit 7-1 NotesMr. Hefti – Pulaski Biology
Ozone Depletion ► What is it?
• Thinning of ozone layer• Shield of gases 20-50 km
above Earth’s surface that absorb UV radiation from sunlight
OD ► What causes it?
• CFCs (chlorofluorocarbons) break apart ozone molecules
• CFCs were formerly used to make: – Foam– Coolants– Propellants for aerosol cans
OD ► Why is it bad?
• UV exposure causes:– Sunburns– Skin cancer– Damage to eyes– Disrupted growth patterns of producers in food
webs– Genetic mutations
OD ► What can be done about it?
• Ban CFCs [worldwide]
Water Pollution ► What is it?
• Contamination to:– Streams– Lakes– Underground water (aquifers)– Bays– Oceans
• All organisms require water
WP ► What causes it?
• Major water pollutant categories:– Chemical– Biological– Physical materials– Thermal
WP ► Why is it bad?
• Survival impossible in presence of toxic chemicals or harmful microorganisms
• Polluted water causes people to become ill or develop defects
WP ► What can be done about it?
• Clean Water Act (1972) – outstanding legislation• Sewage treatment• Discourage careless dumping through fines• Limit erosion