Chapter 20 Global Climate Change

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

Introduction to Climate Change  "Scientific evidence for warming of the climate system is unequivocal." - Intergovernmental Panel on Climate Change  IPCC Climate Report   HDRSC3#view=detail&mid=F8657BC6542C701ABE80F8657BC6542C701ABE80 HDRSC3#view=detail&mid=F8657BC6542C701ABE80F8657BC6542C701ABE80 HDRSC3#view=detail&mid=F8657BC6542C701ABE80F8657BC6542C701ABE80

Evidence of Climate Change  Spring in N. hemisphere now begins 6 days earlier

Evidence of Climate Change   Sea level rise

Evidence of Climate Change   Global temperature rise

Evidence of Climate Change   Warming oceans

Evidence of Climate Change   Shrinking ice sheets Flowing meltwater from the Greenland ice sheet

Evidence of Climate Change   Declining Arctic sea ice

Evidence of Climate Change   Glacial retreat

Evidence of Climate Change   Extreme events

Evidence of Climate Change   Ocean acidification

Introduction to Climate Change: Mean Annual Global Temperature 1960–2007

Causes of Climate Change  Greenhouse gas concentrations increasing

Causes of Climate Change  Increased concentration of CO 2  Burning fossil fuels in cars, industry and homes  Deforestation  Burning of forests

Greenhouse Effect

Pollutants That Cool the Atmosphere  Atmospheric Aerosols  Both human and natural sources  Tiny particles that remain in troposphere for weeks or months  Often contain sulfur  Complicates models of climate change

Climate Models  Climate affected by:  winds, clouds, ocean currents, and albedo  Advanced models can project future warming events  Models have limitations

Effects of Global Climate Change  Wildfire in California

Effects of Global Climate Change: 1. Melting Ice and Rising Sea Levels Sea level rise caused in 2 ways 1. Thermal Expansion 2. Melting of land ice  Melting has positive feedback  Increased melting decreases ice, which decreases albedo leading to further warming

Glacier National Park Melting Ice and Rising Sea Levels

Impacts in Fragile Areas  Eskimo Inuit  Climate change isaltering their existence  Wildlife displaced  Reduced snow cover and shorter river ice seasons  Thawing of permafrost (right)  Tuvalu- threatened by permanent flooding on their island

Effects of Global Climate Change: 2. Changing Precipitation Patterns  Some areas will get more water, some areas will have greater droughts

Effects of Global Climate Change: 3. Effects on Organisms  Zooplankton in parts of CA have decreased by 80% since 1951  Effecting entire food chain  Decline in krill around Antarctica  Species have shifted their geographic range  Migrating birds are returning to summer homes earlier

Effects on Organisms: Coral Reefs  Coral reefs can be bleached (right) due to increase in water temperature

Effect on Organisms: Vegetation

4. Effects on Human Health  Increased number of heat-related illnesses and deaths

5. Effects on Agriculture  Difficult to anticipate  Rise in sea level will inundate farmland  Pests?  Warmer temperatures will decrease soil moisture- requiring more irrigation  Location where certain crops can be grown may change

International Implications of Climate Change  Developed vs. Developing countries

Dealing with Global Climate Change Two ways to manage climate change 1. Mitigation: Limiting greenhouse gas emissions to moderate global climate change 2. Adaptation: Learning to live with environmental changes and societal consequences brought about by global climate change

Relationship Between Mitigation and Adaptation

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

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

International Efforts to Reduce Greenhouse Gas Emission  Kyoto Protocol  Legally binding  Provides rules on reducing greenhouse gases  US and Australia have not sign it - it will be difficult to implement without US backing

  Chapter 21: Global Climate Change Climate Crisis Network   Goddard Institute for Space Studies: Surface Temperature Analysis   United Nations Intergovernmental Panel on Climate Change   US Global Change Research Program   Pew Center on Global Climate Change   World View of Global Warming - The Photographic Documentation of Climate Change