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  1. 1. Definition of Global Warming: Gradual increase in the earths surface temperature.Popular usage definition: Warming caused by human activity.Technical term for this: Anthropogenic global warming.Definition of Greenhouse Gas: A gas, like CO2, which traps the suns heat.Human causes: Carbon dioxide (CO2), e.g. exhaust from cars and power plants.Natural causes: Some claim the sun is getting hotter.What Causes Global Warming, human activity or the sun? The final answer is not in,but you can see the results so far. (1) Exhaust is clearly the source of CO2. (2) Everyonenow agrees the earth is warming. (3) Decide for yourself if warming is better explainedby CO2, or the suns heat.
  2. 2. The Effects of Global Warming. We can see the long-term effects coming in themelting of polar ice and glaciers. But a powerful trend in Atlantic hurricane data indicateswe can already see the impact. Katrina was partly the result of a normal weather cycle,but that cannot explain away stronger hurricanes world wide.Can we Stop Global Warming?Its too late for that, but we can slow it down and lessen its effects. CO2 does not last aslong in the air as was once thought, so the big problem is slowing human use of fossilenergy, especially coal. (Especially since CO2 goes into the ocean and destroys coralreefs.)We dont need absolute scientific proof before we take precautions.Quite a lot can be done rather cheaply. Here are the directions which look most promisingat present. • Hybrid cars • Nuclear power • CO2 sequestration (pumping it back in the ground) • Wind powerWhy are these cheap?First, energy is only about 5% of all costs.Second, everyway of using less fossil fuel saves about $60/gallon.Third, the market always leaves some low-hanging fruit.HYBRID CARS. These still cost more than they save, but not too much, and lots ofpeople like the idea of polluting less. We will eventually switch over almost completelyand the sooner the better--theres lots of room for savings here.NUCLEAR POWER. Nuclear power still has problems, but makes no C02. A highpriority needs to be placed on solving the nuclear-waste problem.PUMPING C02 UNDERGROUND. It seems incredible, but they do it all the time toforce oil out of oil wells. US DOE has a big project to study this. It may turn out to be tooexpensive, but it is considered to be one of the best options by those in the know.WIND POWER. ZFacts will be studying this option soon. It is nearly break-even buthow much could be installed? Is 5% of total power realistic? Right now that seems veryfar off.
  3. 3. Global warming is the increase in the average temperature of Earthsnear-surface air and oceans since the mid-20th century and its projectedcontinuation. Global surface temperature increased 0.74 ± 0.18 °C(1.33 ± 0.32 °F) between the start and the end of the 20th century.[2][A]The Intergovernmental Panel on Climate Change (IPCC) concludes thatmost of the observed temperature increase since the middle of the 20thcentury was very likely caused by increasing concentrations ofgreenhouse gases resulting from human activity such as fossil fuelburning and deforestation.[2] The IPCC also concludes that variations innatural phenomena such as solar radiation and volcanic eruptions had asmall cooling effect after 1950.[3][4] These basic conclusions have beenendorsed by more than 40 scientific societies and academies of science,[B]including all of the national academies of science of the majorindustrialized countries.[5]Climate model projections summarized in the latest IPCC report indicatethat the global surface temperature is likely to rise a further 1.1 to 6.4 °C(2.0 to 11.5 °F) during the 21st century.[2] The uncertainty in thisestimate arises from the use of models with differing sensitivity togreenhouse gas concentrations and the use of differing estimates offuture greenhouse gas emissions. Most studies focus on the periodleading up to the year 2100. However, warming is expected to continuebeyond 2100 even if emissions stop, because of the large heat capacity ofthe oceans and the long lifetime of carbon dioxide in the atmosphere.[6][7]An increase in global temperature will cause sea levels to rise and willchange the amount and pattern of precipitation, probably includingexpansion of subtropical deserts.[8] Warming is expected to be strongestin the Arctic and would be associated with continuing retreat of glaciers,permafrost and sea ice. Other likely effects include changes in the
  4. 4. frequency and intensity of extreme weather events, species extinctions,and changes in agricultural yields. Warming and related changes willvary from region to region around the globe, though the nature of theseregional variations is uncertain.[9]Political and public debate continues regarding global warming, itscauses and what actions to take in response. The available options aremitigation to reduce further emissions; adaptation to reduce the damagecaused by warming; and, more speculatively, geoengineering to reverseglobal warming. Most national governments have signed and ratified theKyoto Protocol aimed at reducing greenhouse gas emissions.