Global Warming

1. Global Warming Erin Lee Wes Ehninger Lannie Davis Laura Burns

2. What is Global Warming? • The Earth's surface temperature has risen by about 1 degree Fahrenheit in the past century, with accelerated warming during the past two decades. • There is new evidence that most of the warming over the last 50 years has been attributed to human activities. • Human activities have altered the chemical composition of the atmosphere through the buildup of greenhouse gases – primarily carbon dioxide, methane, and nitrous oxide. • Since 1980, we have experienced 19 of the 20 warmest years on record; all three of the hottest years ever recorded have taken place since 1998. • Global warming has been particularly strong over the past 20 years. EL

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4. The Greenhouse Effect • Since the beginning of the industrial revolution, Carbon dioxide concentrations have increased by 30%, methane concentrations have more than doubled, and nitrous oxide concentrations have risen15%. • These increases have enhanced the heat-trapping capability of the earth’s atmosphere. • Energy from the sun drives the earth’s weather and climate and heats the earth’s surface. The earth then radiates energy back into space. Atmospheric greenhouse gases (water vapor, carbon dioxide, and other gases) trap some of the outgoing energy, retaining heat somewhat like the glass panels of a greenhouse • This is how we get the “Greenhouse Effect” EL

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6. Cont… • Without this natural “greenhouse effect,” temperatures would be much lower than they are today making life impossible. Because of greenhouse gases, the earth’s average temperature is about 60 degrees Fahrenheit. • However, problems may arise when the atmospheric concentration of greenhouse gases increases. • The key greenhouse gases emitted by human activities remain in the atmosphere for periods ranging from decades to centuries. • Greenhouse gases trap heat in the Earth's atmosphere and in turn warm the planet. EL

7. What has this produced? • The planet has warmed up by 1°F since the late 19th century and it will only get worse. • Warming has occurred in both the northern and southern hemispheres, and over the oceans. • This has been proven by looking at melting glaciers, decreased snow cover in the northern hemisphere, and also even by warmth underground EL

8. GLOBAL WARMING and the FUTURE Is the damage already done or is there still hope? * IF we don’t act now, our children will inherit dirtier water and air, a hotter world that has more droughts, wildfires and more severe floods * LD

9. CONSEQUENCES of global warming…climate pattern changes, droughts and wildfires, intense rainstorms, melting water, sea levels rising and species die-off • The global temperature increased by 1 degree Fahrenheit over the last century and potentially will increase more rapidly in future centuries. • The Earth has experienced 19 or its 20 hottest years on record, with 1998 the hottest and 2002 and 2003 ranking in second and third. • In 2002, the Western US had its second worst wildfire season in the last 50 years. More than 7 million acres burned and Colorado, Arizona and Oregon had their worst seasons ever. Dry Conditions produced the worst wildfires in Florida in 50 years. LD

10. Warmer temperatures increase the energy of the climatic system and lead to a greater number of rainfall. National yearly rainfall increased between 5 and 10 % since the 20th century because of the heavy downpour in some areas. • Rising Global Temperatures will speed up the process of melting glaciers and cause early ice thaw on lakes and rivers. At the current rate of melting, all of the glaciers located in the Glacier National Park will be completely gone by 2070. • Because of melting ice and glaciers, the current pace of sea-level rise is more than three times the historical rate and is accelerating. The satellite photo above shows the Larson B ice shelf on Jan. 31, 2002. Ice appears as solid white. Moving to the right, in photos taken Feb. 17 and Feb. 23, the ice begins to disintegrate. In the photos at far right, taken Mar. 5 and Mar 7, see water (blue) where solid ice had been in the past, and that a portion of the shelf is drifting away.Photos: National Aeronautics and Space Administration. LD

11. Over the past 25 years, there has been a 33% shrink of some penguin populations in parts of Antarctica due to the decline in winter sea-ice habitat. • In Washington’s Olympic Mountains, sub-alpine forest has invaded higher elevation alpine meadows. In Bermuda as well as other places, forests are being lost. Warmer temperatures are causing some ecosystems, including alpine meadows in the Rocky Mountains, (pictured) to disappear slowly but surely. LD

12. GreenlandGlaciers along the southeastern coast of Greenland are thinning by more than 3 feet a year – many believe because of global warming, according to a new study by NASA scientists. LD

13. Long term consequences The entire US will warm, though sulfates could limit the warming in areas. Scientist are not able at this time to say which parts of the US will become drier or wetter. But the trend is expected to be one that goes towards increased precipitation and evaporation as well as more intense rainstorms and much drier soils. As of right now though, the potentially most crucial impacts depend upon whether rainfall increases or decreases, which is hard to project for certain areas. Also, a lot of damage has been done, but depending upon the role we take in the future, many of the worst long term consequences of global warming could still be on their way. LD

14. Impacts of Global Warming

15. Global Warming Impacts • A study done by U.S. Market Consequences of Global Climate Change, found that any species or ecosystem that is less able to adapt- for example coral reefs, coastal wetlands, already endangered species, and alpine forests- is at the greatest risk. • The southeast and the Southern Great Plains are at most risk due to their low-lying coasts and the impacts of warmer conditions on agriculture. • Laura Burns

16. Impacts of Global Warming on People • The effects of climate on people may vary… • Economically devolved societies, like those in North America, Europe and Japan, could use technology to reduce impacts. • For example, they might develop new crop varieties, construct new water systems, and limit coastal development. Some northern countries, such as Canada and Russia, might even benefit from longer growing season and lower heating bills if the climate becomes warmer. • Laura Burns

17. Impacts of Global Warming on People • In contrast, economically less developed societies, like those in parts of Africa, Asia, and South America depend much more directly on climate, and could be hit much harder by sudden or larger changes. • Places like coastal Bangladesh and low-lying islands, could be flooded by storms or rising sea level. • Droughts in Africa might become more serious. • Laura Burns

18. Impacts of Global Warming on People • Developing countries have far fewer resources for adapting to such changes. • They may not be able to afford large projects such as sea walls or aqueducts. Peasant farmers may have difficulty adopting new agricultural practices. • The resulting social tensions could lead to more political unrest and large-scale migrations. • Laura Burns

19. Impacts of Global Warming on the Natural Environment • Plant migration: Climate may change faster than plants can move from one region to another. This may cause species extinction, lower biodiversity, and changes in the way species interact. • Coral reefs: Slightly warmer tropical water may kill the algae which reef animals use for food. • Laura Burns

20. Impacts of Global Warming on the Natural Environment • Changes in insect pests: • Climate change can affect the number and kinds of pests directly. It can also affect them by changing the mix of plant varieties and their nutrient content. This can influence plant survival, food chains, and the spread of disease. • Mangrove swamps: Mangrove swamps are important breeding grounds for many animals that live in water. Increased ocean flooding may damage these areas by changing the supply of nutrients and the amount of salt. • Laura Burns

21. Actions Taken to Prevent Global Warming Governments can adopt a range of options for reducing greenhouse gas emissions, including: -increasing energy efficiency standards -encouraging the use of renewable energy sources (such as wind and solar power) -eliminating subsidies that encourage the use of coal and oil by making them artificially cheap -protecting and restoring forests, which serve as important storehouses of carbon W.E.

22. What can Individuals Do? • Individuals can reduce the need for fossil fuels and often save money by: • driving less and driving more fuel-efficient and less-polluting cars • using energy-efficient appliances • insulating homes • using less electricity in general W.E.

23. U.S. Response to Global Warming • 29 States have completed or are working on action plans to reduce Greenhouse Gas emissions. • States have access to a “state action list” to see what other states are implementing to reduce emissions. • Implementation of the Energy Star program, an initiative to reduce CO2 emissions by businesses and industry. W.E.

24. Kyoto Treaty • U.N. Sanctioned International Agreement to reduce climate changing gasses in 1997 • Called for vast reduction in U.S. emissions • Bush Administration refused to sign treaty, arguing it would devastate American industry and business. W.E.

25. What else can be done? • “Fortunately, a number of analyses indicate that current technologies do have the capability to reduce emissions in the next few decades by very large amounts, thus enhancing the ability of our generation and those that follow to stabilize concentrations at levels as low as 450ppm. The "toolbox" of current lower carbon technologies is well-known: substantial reductions in energy consumption by vehicles, appliances, buildings and the megalopolises they form are achievable without any loss in services15; renewable resources like wind, solar and biomass are already cost-competitive in certain applications…” (www.nrdc.org) W.E.

26. Sources • http://www.marshall.org/article.php?id=67#1 • http://www.epa.gov/globalwarming/ • http://www.earthinstitute.columbia.edu/crosscutting/climate.html • http://yosemite.epa.gov/oar/ • http://nrdc.org/globalwarming/fcons.asp • (www.prweb.com/releases/2004/4/prewebxml121971.php) • www.gcrio.org/gwcc/part2.html