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Hurricanes, Tigers, and GW Kyle Avery Colin Curwen-McAdams Spencer Johnson Stephanie Ostrander 100 miles http://www.stormcenter.com/media/060103/image1.jpgwww.chagrin-falls.k12.oh.us
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Cyclones Warm ocean temperatures –>26.5 C. –Cyclone Fuel Anti-cyclone Low surface friction and shear http://coastal.er.usgs.gov/hurricanes/rita http://www.ucsusa.org/global_warming/science/hurricanes-and-climate-change.html
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The GW/Hurricane connection The mean temperature of the planet is increasing over time. + Cyclones are fed by warmer water. = Cyclone frequency and intensity increase. Cyclones: Hurricane and tropical storm data Wind speed as a proxy for intensity Each storm a distinct event Null hypothesis: There is a linear relation between time and hurricane intensity and frequency.
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Frequency of Hurricanes and Tropical Storms by Decade Decade Frequency
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Chi-Squared Table Inclusive Data Set Fo=Frequency observed Fe= Frequency expected
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Frequency of Hurricanes and Tropical Storms by Decade Data without 2000-2007 Decade Frequency
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Chi-Squared Table Data without 2000-2007
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Chi-Squared Statistics Degrees of Freedom: 16 inclusive data; 15 without 2000-2007 16 15 P=.05 Critical Value= 26.30 25.00 P=.01 Critical Value= 32.00 30.58 P=.001 Critical Value= 39.25 37.70
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Average Wind Speed As a Function of Time Speed in knots 16 independent data points Data points are 10 year averages Degrees of Freedom = 16 (26.30 at p=.05)
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Chi 2 Values XFoFe(Fo-Fe)^2(Fo-Fe)^2/Fe 185078.174.989.730.13 186075.774.870.690.01 187075.374.770.280.00 188077.474.667.490.10 189073.574.561.120.02 190066.274.4568.140.92 191071.774.357.020.09 192076.974.257.040.09 193067.374.1446.810.63 194071.274.048.050.11 195083.473.9389.621.21 19608073.8338.080.52 197072.173.722.640.04 198072.173.622.310.03 199072.973.520.380.01 200073.373.410.010.00 3.90 185078.176.363.020.04 186075.776.060.130.00 187075.375.750.210.00 188077.475.453.800.05 189073.575.152.710.04 191071.774.548.050.11 192076.974.237.110.10 194071.273.635.890.08 197072.172.710.380.01 198072.172.410.100.00 199072.972.110.630.01 200073.371.802.240.03 0.46
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Regression slopes -0.01 and -0.03 Standard deviation 4.42 Average 7.19
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What’s Wrong with Hurricanes Anyway?
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What Do We Really Know? Emanuel reports that power dissipated by tropical cyclones in the Atlantic has doubled since the 1950s. Frequency and intensity have both contributed to this increase. Chris Landsea disputes Emanuel’s PDI and says there is no correlation (December 2005, Nature) World Meteorological Society Says that no individual storm can be linked to climate change. Changes in the way hurricanes are measured make finding trends a dodgy proposition. Timescale of measurements is fairly short Distortion in the Media
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The Cost Cost of storms is increasing
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What Should We Do? Learn from past mistakes Education about storms Don’t build below sea level or other especially precarious places Invest in preventative measures
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The Real Problem
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