1. Hosted by Decisioneering, Inc. July 19, 2007 Global Warming To listen to the session on your phone , follow the instructions in the “ Join Teleconference ” pop up dialog box which will appear in a few moments. To listen to the session on your computer speakers instead of your phone, follow the instructions in the “ Join Internet Phone ” pop up dialog box which will appear in a few moments. Please DO NOT join both, as this is redundant. Guest Speaker Gaetan ‘Guy’ Lion
6. The Regression Models: Log & Linear Until recently, climatologists debated whether the relationship between CO2 and temperature was logarithmic or linear.
7. The Natural Log Model Simulation Year CO2 conc . The model simulates temperature level by 2090 – 2099 two ways. One way just picks a year at random within the decade. The other way calculates the average over the decade.
10. IPCC Scenarios Definitions Source: IPCC Summary for Policymakers. Technological energy emphasis seems to be the most influential factor in determining CO2 concentration CAGR.
15. Temp. Increase. Models vs 3 IPCC scenarios Among the IPCC scenarios, B1 is the low scenario, A1B is the mid level one, and A1FI is the high one. Watch carefully for the scale of the Y axes here.
16. Testing our regression coefficients vs IPCC scenarios The coefficients of the natural log model replicate reasonably well the IPCC best estimates up to CO2 concentration of 850 ppm. Linear model LN model
18. Another view of volatility. LN model vs B1 The natural log model and scenario B1 (IPCC) generate about the same best estimate in temperature increase (~ 1.8 degree Celsius). But, the confidence interval for the B1 scenario (green) is much wider at 1.8 degree Celsius vs only 0.68 degree Celsius for the log model (orange). B1 scenario LN model
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20. Generating higher Volatility In this log model, I used the standard errors of the intercept and slope as random variables instead of the standard error of the regression. To moderate excessive volatility I used a high negative correlation (-0.95) between the two standard errors. But, resulting volatility was still way too high with a Confidence Interval that is too wide including large decrease in temperature.
21. Thank you for attending the Web Seminar Global Warming Gaetan “Guy” Lion E-mail: gaetanlion@gmail.com July 19, 2007 Decisioneering, Inc. 1515 Arapahoe St., Ste 1311 Denver, Colorado 80202 303-534-1515 www.crystalball.com