12B. ClimateChange

Higher co2 anthropogenic influence

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Unformatted text preview: ely” that emissions of heat- trapping gasses from human activities have caused “most of the observed increase in globally averaged temperatures since the mid-20th century.” Higher CO2: Anthropogenic Influence http://www.npr.org/templates/story/story.php?storyId=9885767 CO2 is rising. We burn lots of fossil fuel (~$2000 each, each year, just to import oil), and we see CO2 from our tail pipes in the air and the ocean. This is the Keeling Curve showing the rise since 1958. The wiggles are the “breathing” of the seasons (spring leaf growth and autumn leaf death). It really is our CO2. What we burn is in the air and the ocean. Tracers in air confirm this. For example, burning fossil fuels uses oxygen, but volcanoes don’t. The drop in oxygen is clear. If CO2 from volcanoes, ocean, etc., nothing is burning so no oxygen is used to make CO2 If CO2 from burning (living or formerly living plants) oxygen is used R. Keeling and C.D. Keeling, Scripps Institute of Oceanography (We’ll still be able to breathe!) Global Warming Forecast Higher CO2 causes global warming ~0.8°C (1.5°F) 2006 2-4°C (3-5°F) by 2100 IPCC Third Assessment Report: Climate Change 2001 Synthesis Report ??? ??? Rise to come Rise so far Year IPCC, 2001 Warming so far Warming to come (world continues past 2100…) 25 Brief Summary of Likely Impacts Grain-belt drying for crops Sea-level rise Tropical diseases no longer frozen Loss of unique ecosystems Damages a few percent of world economy (well over $1 trillion per year) or more Uncertainties? Costs slightly less, slightly more, or much more--don’t find much less Northern Hemisphere Temperature Reconstructions “It can be said with a high level of confidence that global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries” “…the committee finds it plausible that the Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium.” National Research Council Potential Effects of Global Climate Change Climate Patterns Extreme heat, heat waves, and heavy precipitation are very likely to become more frequent Potential Effects of Global Climate Change Climate Patterns May change frequency and intensity of violent storms such as hurricanes due to excess heat transfer Potential Effects of Global Climate Change 2005 Hurricane Season - most active in Atlantic history with at least 2,280 deaths and record damages of over $128 billion expected observed World’s oceans have absorbed 20 times more heat as the atmosphere warme...
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This note was uploaded on 04/02/2013 for the course 460 202 taught by Professor Sugarplum during the Fall '13 term at Rutgers.

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