GLOBAL WARMING: THE SIGNS AND THE SCIENCE PBS Home Video Host: Alanis Morissette Corporate Funding (always check out sponsors to determine the possibility of advocacy and influence by sponsors) Toyota Motor Sales – manufacturer/seller of hybrid vehicles Swiss Re – Capital and risk management and insurance GLOBAL WARMING CAN BE FRAMED AS HUMANS VS. FORCES OF NATURE 1. the most talked about problems: Increasing drought Rising sea level Pole ward movement of tropical diseases Increasing frequency of extreme weather 2. The majority of scientists view the evidence as telling us that global warming is real and the effect is accelerating. EVIDENCE - ICE In the last 100 years global average temperature has risen 1oF – a huge amount for a global average. In the arctic and antarctic the temperature rise is greater (as climate models predict) and in the past 50 years amounts to 4o to 7oF. Arctic – Arctic Ocean sea ice is Forming later Melting earlier Covers less area and Is thinner Antarctic - Ice Shelves are disintegrating Jan to Mar 2002 – Larsen Ice Shelf, a floating slab of ice the size of Rhode Island disintegrated. See images below and check out the links: http://earthobservatory.nasa.gov/Study/LarsenIceShelf/ http://web.pdx.edu/~chulbe/science/Larsen/larsen2002.html In Africa Mt. Kilimanjaro will soon be ice free and glaciers in the Swiss Alps are retreating rapidly. EVIDENCE – ATMOSPHERIC CIRCULATION The major circulation systems of Earth are migrating and as a result climates are changing and may be destabilizing threatening to change agricultural productivity. Drought prone areas like the Great Plains of the U.S. will become drier (warmer weather means more evaporation) Flood prone areas will get more precipitation (the evaporated water has to go somewhere and it will be released by more intense lift in areas where it rains) Evidence indicates that this is happening now. A WAY TO LOOK AT GLOBAL WARMING IS: Ancient sunlight vs. current sunlight – ancient sunlight refers to energy stored in fossil fuels (thus ancient sunlight) in the form of hydrocarbons. When used these fuels release carbon to the environment and increase CO2 in the system. Increased CO2 will affect: Photosynthesis Blood chemistry Ocean acidity and of course the Greenhouse effect Soil chemistry – nitrogen from fossil fuels fertilizes soil micro organisms which then emit even more CO2 THE BIGGEST PLAYERS IN THE IMMEDIATE FUTURE: China and India with: Large populations and An increasing standard of living = INCREASED GREENHOUSE EMISSIONS Increasing World Population: As many as 9.3 billion people by 2050 EVIDENCE – HEALTH EFFECTS The CO2 fertilization to date has lead to an increase of 9% in plant growth and a 61% increase in pollen production->allergy increase. Henta virus and West Nile virus (spread by mosquitoes). Insect infestations will increase – bark beetles in Alaska – not in the film. THE INVESTIGATION Sea temperatures are warming and that means: 1. more energy for hurricanes 2. more heat to melt ice leading to a. more fresh water in the polar oceans – decrease of the circulation of the conveyor belt – may have been a factor in the Little Ice Age. b. less albedo from less ice – positive feedback c. increasing sea level 3. water will expand and sea level will rise from this too 4. Less dissolved CO2 in the warmer water so even more in the atmosphere. El Niño frequency may increase] Barrier islands may disappear (they already have in many areas south of New Orleans even pre-Katrina). The situation 1. Climate will be more variable = less reliable harvests 2. Food need will be greater = more hunger 3. Civilization may be destabilized = remember the Little Ice Age and the French Revolution. THE NEXT STEPS: HOW DO WE CLEAN UP OUR ACT? More reliance on current sunshine – solar energy alternatives - in one day the sun sends the equivalent of 27 years of energy for all Earth uses. In some areas you can sell power back to the energy company. Clean coal – less particulate by still a great deal of CO2 Wind power – wind farms Bio-diesel Hybrid technology (then hydrogen fuel cells) Use of landfill methane Energy efficient homes Agriculture = hybrid crops that create more biomass and thus remove carbon from the system. Pump CO2 into the ground. OLD WAY OF THINKING = CONSERVATION AND NEW TECHNOLOGY THREATENS JOBS. NEW WAY OF THINKING – NEW TECHNOLOGY CREATES JOBS