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 2000-2009 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 CO2 (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 CO2 sink - excess CO2 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

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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

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 zonesNYC sewer line