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We have made considerable progress in defining the ÒfingerprintsÓ of different forcings
1. Solar
3. Well-mixed greenhouse gases
5. Sulfate aerosol particles
2. Volcanoes
4. Ozone
6. 1st five factors combined
Text Box: Height (km)Text Box: Height (km)Text Box: Height (km)Text Box: Pressure (hPa)Text Box: Pressure (hPa)Text Box: Pressure (hPa)
¡C/century
Santer et al., Climate Change Science and Policy, 2007
 Detecting ÒsignificantÓ climate change means showing that a given change in climate is unusual relative to some yardstick that you have of ÒnormalÓ behavior.
 If you feel hot, and measure a body temperature of 102oF, then youÕve ÒdetectedÓ a fever - you know that that this elevated temperature is outside the limits of ÒnormalÓ body temperature.
 But this measurement doesnÕt give you the cause of the fever.
 To deduce the cause, youÕll probably need to undergo some more sophisticated tests - perhaps urine and blood analyses, maybe even x-rays or CAT scans.
 Once you have the results from these tests, itÕs much easier to narrow down the potential causes of the fever.
 This is attribution - the process of establishing cause and effect.