Climate Change and Ozone Loss G. Tyler Miller’s Living in the Environment 13 th Edition Chapter 18 G. Tyler Miller’s Living in the Environment 13 th Edition Chapter 18 Modified by Charlotte Kirkpatrick Dr. Richard Clements Chattanooga State Technical Community College Modified by Charlotte Kirkpatrick Dr. Richard Clements Chattanooga State Technical Community College

Key Concepts  How does the Earth’s climate fluctuate  What factors affect climate  What are the possible effects of global warming  What can humans do about potential climate change  How are human activities affecting the ozone layer  What can humans do about changes in the ozone layer

Past Climate Change  Past global temperatures  Recent trends in global temperatures Fig p. 447

The Natural Greenhouse Effect  Greenhouse effect  Greenhouse gases (Refer to Table 18-1 p. 448) Fig p. 128

Climate Change and Human Activities  Increased use of fossil fuels  Deforestation  Global warming  Melting icecaps and glaciers  Coral reef bleaching Refer to Table 18-2 p. 451

Projecting Future Changes in Earth’s Climate  Climate models (see Spotlight p. 457)  Apparent influence of human activities  Could be natural changes Fig p. 455

Factors Affecting Changes in Earth’s Average Temperature  Changes in solar output  Changes in Earth’s albedo  Moderating effect of oceans  Clouds and water vapor  Air pollution Fig p. 457

Some Possible Effects of a Warmer World Fig p. 461 Fig p. 461

Solutions: Dealing with the Threat of Climate Change Options  Do nothing  Do more research  Act now to reduce risks  No-regrets strategy Fig p. 466

Removing CO 2 From the Atmosphere Fig p. 467 Tree plantation Coal power plant Tanker delivers CO 2 from plant to rig Oil rig Crop fieldSwitchgrass field Spent oil reservoir is used for CO 2 deposit CO 2 is pumped down to reservoir through abandoned oil field Abandoned oil field CO 2 is pumped down from rig for Deep ocean disposal = CO 2 deposit = CO 2 pumping

Reducing Greenhouse Gas Emissions Rio Earth Summit (1992) Kyoto Treaty (1997) Some US CO 2 Reductions Refer to Fig p. 472

Ozone Depletion in the Stratosphere Importance of Ozone  Terrestrial life  Reduce sunburn  Prevents tropospheric ozone Fig p. 473

Ozone Depleting Chemicals  Chlorofluorocarbons (CFCs)  Halons  Methyl bromide  Carbon tetrachloride  Methyl chloroform  Hydrogen chloride  Sources of CFCs

Seasonal Thinning at the Poles  Ozone thinning (hole)  Polar vortex Fig p. 475

Reasons for Concern  Increased incidence and severity of sunburn  Increase in eye cataracts  Increased incidence of skin cancer  Immune system suppression  Increase in acid deposition  Lower crop yields and decline in productivity Refer to Fig p. 476 Refer to Fig p. 476

Solutions: Protecting the Ozone Layer  CFC substitutes (see Table 18-3 p. 477)  Technofixes  Montreal Protocol Fig p. 479