Environmental Issues

Greenhouse Effect What is it? Process by which gases in the atmosphere trap and retain heat Process by which gases in the atmosphere trap and retain heat Maintains temperature to sustain lifeMaintains temperature to sustain life Amount of energy coming in should equal amount of energy going outAmount of energy coming in should equal amount of energy going out Short wavelength radiation penetrates atmosphere; long wavelengths from Earth’s surface trappedShort wavelength radiation penetrates atmosphere; long wavelengths from Earth’s surface trapped

Greenhouse Effect Enhanced Human actions increase amount of greenhouse gasesHuman actions increase amount of greenhouse gases Increased gases lead to increased global temperaturesIncreased gases lead to increased global temperatures

Greenhouse Effect Gases Chlorofluorocarbons (CFC’s)Chlorofluorocarbons (CFC’s) Methane (CH 4 )Methane (CH 4 ) – Burning vegetation, industrial emissions Carbon Dioxide (CO 2 )Carbon Dioxide (CO 2 ) – Digestive process of animals; rice cultivation Nitrous Oxide (N 2 0)Nitrous Oxide (N 2 0) – Burning of oil, coal, and natural gas; deforestation – Refrigerants, aerosols

Greenhouse Gases Consequences Increase in temperature from 1.4°C to 5.8°C by 2100Increase in temperature from 1.4°C to 5.8°C by 2100 Produce global sea level riseProduce global sea level rise Increase temperatures result in glacier and ice sheet meltingIncrease temperatures result in glacier and ice sheet melting Greenland Summer slush expanding

Sea Level Rise Global sea level rise estimated to have risen cm over last 100 yearsGlobal sea level rise estimated to have risen cm over last 100 years The next 100 years average sea level projected 50 cm higherThe next 100 years average sea level projected 50 cm higher

Sea Level Rise Consequences The oceans are predicted to rise about 0.5 – 10.0 meter by 2100The oceans are predicted to rise about 0.5 – 10.0 meter by 2100 Beach retreat and flooding pose a high risk along east coast and gulf stateBeach retreat and flooding pose a high risk along east coast and gulf state Bluff collapse is greatest threat along CaliforniaBluff collapse is greatest threat along California

Beach Erosion California – 86% of California coasts are classified as actively eroding – 1 in 4 homes within 500 feet of coast will be lost to erosion in 60 years Beach erosion is a serious problem for coastal communitiesBeach erosion is a serious problem for coastal communities Some causes:Some causes: – Sea level rise – Building near coast – Efforts to reduce erosion

Beach Erosion California Santa Barbara, California

Ocean Pollution Sources Oil spillsOil spills Toxic wastesToxic wastes DebrisDebris Raw sewageRaw sewage

Coral Reefs Provide natural habitat for 25% of marine lifeProvide natural habitat for 25% of marine life Serve as breeding ground for marine organismsServe as breeding ground for marine organisms Natural breakwater for strong wavesNatural breakwater for strong waves

Coral Reefs Issues PollutionPollution – Human waste, fertilizer, and pesticides Destructive fishing methodsDestructive fishing methods – Dynamite and cyanide Global warmingGlobal warming – Fragile living conditions At the present rate of destruction, 70% of world’s coral reefs will be gone in the next yearsAt the present rate of destruction, 70% of world’s coral reefs will be gone in the next years Completely gone by 2100Completely gone by 2100