 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

 Greenhouse Gas  Gas that absorbs infrared radiation  Ex: Carbon dioxide, methane, nitrous oxide (N2O), chlorofluorocarbons and tropospheric ozone  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…think heat  Greenhouse Effect  Increase of heat in a system

 Some evidence for Climate Change  Temperature increase of 1.4 degrees F since 1880 ▪ Extreme northern latitudes – 7.4 increase (40% of N. polar ice cap melt)  9 of the 10 warmest years between  Ice core sampling measures greenhouse gases up to 500,000 years ago. (CO2 and temp. correlate)  Human produced greenhouse gases are most plausible explanation

 Greenhouse gas concentrations increasing

 Increased concentration of CO 2 (right)  Burning fossil fuels in cars, industry and homes  Deforestation  Burning of forests

 Atmospheric Aerosols tend to cool the atmosphere  Both human and natural sources  Tiny particles that remain in troposphere for weeks or months  Contain many chemicals, but often contain sulfur  Complicates models of climate change (but accounted for)

 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

 Ocean as CO 2 sink - excess CO 2 is starting to harm ocean life (acidification  decline of coral reefs)

 Sea level rise caused in 2 ways  Thermal Expansion ▪ Water expands as it warms  Melting of land ice ▪ Retreat of glacier and thinning of ice at the poles  Melting has positive feedback  Increased melting decreases ice, which decreases albedo leading to further warming  Threatens small islands and coasts: flooding + erosion and intense storms

 Melting permafrost  Support structure for Tundra plants, houses, roads  Release CO2 and methane from decomposing material (remember bacteria decompose more/faster at warmer temperatures.) ▪ See article See article Near Fairbanks, Alaska

 Some areas will get more water, some areas will have greater droughts  Ex: Hurricanes will likely get stronger due to warmer water  Exaggerate El Nino effects

 Zooplankton in parts of California Current have decreased by 80% since 1951  Effecting entire food chain  Polar ice cap melting – too far for Polar bear to swim to hunt seals  Polar bear  seal (seal carcass to Arctic fox)  Decline in krill around Antarctica  Caused decrease in penguin populations  Species have shifted their geographic range  Migrating birds are returning to summer homes earlier  Food is not available at this time

 Coral reefs can be bleached (right) due to increase in water temperature  Affects coral symbiotes and makes them more susceptible to diseases to which they would otherwise be immune

 Increased number of heat-related illnesses and deaths: malaria, schistosomiasis, leishmaniasis

 Rise in sea level will inundate/destroy flood plains and river valleys (lush farmland)  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  Difficult to anticipate  Productivity will increase in some areas and decrease in others

 Rising sea levels  Change in precipitation patterns  Sensitive organisms decline; decrease # of organisms at bottom of food chain  Increase range of disease causing organisms  Decrease ability to grow crops in certain areas

 Kyoto Protocol  Provides rules on reducing greenhouse gases  US and Australia have not signed it- difficult to implement without US backing ▪ US concern: LDC not have same expectations to lower

 Two ways to attempt to manage climate change  Mitigation/Reduction: ▪ Focuses on limiting greenhouse gas emissions to moderate global climate change  Adaptation ▪ Focuses on learning to live with to the environmental changes and societal consequences brought about by global climate change

 Locate/invent alternative fuels to fossil fuels  Increase efficiency of cars and trucks  Drive less: bike lanes, carpool, wide sidewalks  Sequestering carbon before it is emitted  Plant and maintain trees to naturally sequester carbon

 Rising sea levels and coastal populations  Move inland  Construct dikes and levees  Adapt to shifting agricultural zones  NYC sewer line