Climate Change and Ozone Loss

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Climate Change and Ozone Loss
G. Tyler Millers Living in the Environment 14th
Edition Chapter 21
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Key Concepts

• Changes in Earths 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

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Past Climate Changes

• Past global temperatures

• Recent trends in global temperatures

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The Greenhouse Effect

• Greenhouse effect

• Greenhouse gases (Refer to Table 21-1 p. 464)

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Projecting Future Changes in Earths Climate

• Climate models

Modeling from the 1990

• Apparent influence of human activities

• Could be natural changes

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Climate Change and Human Activities

• Increased use of fossil fuels

• Global warming

• Melting icecaps and glaciers

Planet in Peril Sea Level Rise

• Deforestation

• Rising sea level

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Factors Affecting the Earths Temperature

• Changes in solar output

• Changes in Earths albedo

• Moderating effect of oceans

• Clouds and water vapor

• Air pollution

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Some Possible Effects of a Warmer World
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Possible Benefits from a Warmer Atmosphere
Solutions Dealing with the Threat of Climate
Change

• 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

Options

• Do nothing

• Do more research

• Act now to reduce risks

• Precautionary principle

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Removing CO2 from the Atmosphere
Capture and sequester
Reducing Greenhouse Gas Emissions

• Kyoto Treaty (1997)

• U.S. withdraws from Kyoto Treaty (2001)

• Other reductions in CO2

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Loss of the Ozone Layer Reasons for Concern

• Increased incidence and severity of sunburn

• Increase in eye cataracts

• Increased incidence of skin cancer

Skin Cancer

• Immune system suppression

• Increase in acid deposition

• Lower crop yields and decline in productivity

Seasonal Ozone Layer Thinning at the Poles

• Ozone thinning (hole)

• Polar vortex

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Ozone Depleting Chemicals

• Chlorofluorocarbons (CFCs)

• Halons

• Methyl bromide

• Carbon tetrachloride

• Methyl chloroform

• Hydrogen chloride

Ozone Depletion in the Stratosphere
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Former Uses of CFCs

• Air Conditioners
• Refrigerators
• Spray cans
• Cleaners for electronic parts
• Sterilizing medical instruments
• Fumigants for granaries and cargo ships

Solutions Protecting the Ozone Layer

• CFC substitutes

• Montreal Protocol

• Copenhagen Protocol