1. 20
Global Climate Change

2. Overview of Chapter 20 Introduction to Climate Change
Causes of Global Climate Change
Effects of Climate Change
Melting Ice and Rising Sea Level
Changes in Precipitation Patterns
Effects on Organisms
Effects on Human Health
Effects on Agriculture
Dealing with Global Climate Change
© 2012 John Wiley & Sons, Inc. All rights reserved.

3. Climate Change Terminology
Greenhouse Gas
Gas that absorbs infrared radiation
Positive Feedback
Change in some condition triggers a response that intensifies the changed condition
Infrared Radiation
Radiation that has a wavelength that is longer than that of visible light, but shorter than that of radio waves
Greenhouse Effect
Increase of heat in a system where energy enters (often as light), is absorbed as heat, and released sometime later
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4. Introduction to Climate Change
Evidence for Climate Change
16 warmest years since mid-1800s have occurred since 1990
Phenological spring in N. hemisphere now begins 6 days earlier (date the buds of specific plants open)
Warming is not due to natural causes
Human produced greenhouse gases are most plausible explanation
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5. Introduction to Climate Change: Mean Annual Global Temperature 1960–2010
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6. Greenhouse Gases Greenhouse gas concentrations are increasing
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7. Causes of Climate Change
Increased concentration of CO2 (right)
Burning fossil fuels in cars, industry and homes
Deforestation
Burning of forests
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8. Greenhouse Effect
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9. Pollutants That Cool the Atmosphere
Atmospheric Aerosols
Both human and natural sources
Tiny particles (or sulfur) that remain in troposphere for weeks or months
Sulfur-laden layer in the atmosphere reduces the amount of sunlight reaching earth
Complicates models of climate change
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10. Climate Models Climate affected by:
winds, clouds, ocean currents, and albedo
Used to explore past climate events
Advanced models can project future warming events
Models are only as good as the data and law used to program them
They have limitations
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11. Climate Models
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12. Effects of Global Climate Change
Wildfire in California
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13. Effects of Global Climate Change- Melting Ice and Rising Sea Levels
IPCC projects sea-level rise of18-59cm by 2100
Sea level rise caused in 2 ways
Thermal Expansion
Melting of land ice
Melting has positive feedback
Increased melting decreases ice, which decreases albedo leading to further warming
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14. Melting Ice and Rising Sea Levels
1938
Insert Figure 20.6a
Insert Figure 20.6b
1981
1998
Insert Figure 20.6c
Insert Figure 20.6d
2005
Grinnell Glacier, Glacier National Park
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15. Case-In-Point Impacts in Fragile Areas
Eskimo Inuit live traditional life dictated by freezing climate
Climate change is altering their existence
Wildlife displaced
Reduced snow cover and shorter river ice seasons
Thawing of permafrost (right)
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16. Effects of Global Climate Change- Changing Precipitation Patterns
Some areas will get more water, some areas will have greater droughts
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17. Effects of Global Climate Change- Effects on Organisms
Zooplankton in parts of California Current have decreased by 80% since 1951
Affecting entire food chain
Species have shifted their geographic range
Migrating birds are returning to summer homes earlier
Ecosystems at greatest risk of species loss (short term): coral reefs, mountain ecosystems, coastal wetlands, tundra, and polar spas
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18. Effects on Organisms - Coral Reefs
Coral reefs can be bleached (right) due to increase in water temperature
Affects coral symbiotes and makes them more susceptible to diseases
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19. Effect on Organisms - Vegetation
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20. Effect on Organisms - Vegetation
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21. Effects on Human Health
Increased number of heat-related illnesses and deaths
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22. Effects on Agriculture
Difficult to anticipate
Productivity will increase in some areas and decrease in others
Rise in sea level will inundate flood plains and river valleys (lush farmland)
Effect on pests is unknown
Warmer temperatures will decrease soil moisture - requiring more irrigation
Location (i.e., elevation and altitude) where certain crops can be grown may have to change
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23. International Implications of Climate Change
Developed vs. Developing countries
Differing self- interests
Differing ability to meet the challenges of climate change
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24. Dealing with Global Climate Change
Two ways to manage climate change
Mitigation: Limiting greenhouse gas emissions to moderate global climate change
Adaptation: Learning to live with environmental changes and societal consequences brought about by global climate change
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25. Relationship Between Mitigation and Adaptation
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26. Dealing with Global Climate Change - Mitigation
Locate/invent alternative fuels to fossil fuels
Increase efficiency of cars and trucks
Carbon Capture and Storage
Plant and Maintain trees to naturally sequester carbon
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27. Dealing with Global Climate Change - Adaptation
Rising sea levels and coastal populations
Move inland
Construct dikes and levees
Adapt to shifting agricultural zones
NYC sewer line
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28. International Efforts to Reduce Greenhouse Gas Emission
Kyoto Protocol
Legally binding
Provides operational rules on reducing greenhouse gases
By 2010, 183 countries had ratified it
US has not sign it - it will be difficult to implement without US backing
EPA is taking it upon itself to define laws associated with CO2 reduction in US
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