Climate Change and Ozone Loss G. Tyler Miller’s Living in the Environment 14th Edition Chapter 21

Key Concepts Changes in Earth’s climate over time Factors affecting climate Possible effects of global warming Adapting to climate change Human impacts on the ozone layer Protecting and restoring the ozone layer

Past Climate Changes Past global temperatures Recent trends in global temperatures Fig. 21-2 p. 463

The Greenhouse Effect Greenhouse effect Greenhouse gases (Refer to Table 21-1 p. 464) Fig. 6-14 p. 110

Climate Change and Human Activities Increased use of fossil fuels Deforestation Global warming Melting icecaps and glaciers Rising sea level

Projecting Future Changes in Earth’s Climate Climate models Apparent influence of human activities Could be natural changes

Factors Affecting the Earth’s Temperature Changes in solar output Changes in Earth’s albedo Moderating effect of oceans Clouds and water vapor Air pollution

Some Possible Effects of a Warmer World Fig. 21-12 p. 475

Possible Benefits from a Warmer Atmosphere Less severe winters More precipitation in some dry areas Less precipitation in some wet areas Increased food production in some areas Expanded population and ranges of some species Refer to Fig. 21-13 p. 476

Solutions: Dealing with the Threat of Climate Change Options Do nothing Do more research Act now to reduce risks Precautionary principle Fig. 21-17 p. 479

Removing CO2 from the Atmosphere Fig. 21-18 p. 480

Reducing Greenhouse Gas Emissions Kyoto Treaty (1997) U.S. withdraws from Kyoto Treaty (2001) Other reductions in CO2 Refer to Fig. 21-18 p. 483

Loss of the Ozone Layer: Reasons for Concern Increased incidence and severity of sunburn Increase in eye cataracts Increased incidence of skin cancer Immune system suppression Refer to Fig. 21-23 p. 486 Increase in acid deposition Lower crop yields and decline in productivity

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

Former Uses of CFCs Air Conditioners Refrigerators Spray cans Cleaners for electronic parts Sterilizing medical instruments Fumigants for granaries and cargo ships

Ozone Depletion in the Stratosphere Fig. 21-21 p. 484

Seasonal Ozone Layer Thinning at the Poles Ozone thinning (hole) Polar vortex

Skin Cancers Fig. 21-25 p. 487

Solutions: Protecting the Ozone Layer CFC substitutes Montreal Protocol Copenhagen Protocol Fig. 21-27 p. 489