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Old 12-04-2012, 08:03 AM   #194 (permalink)
Arragonis
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Quote:
Originally Posted by TheEnemy View Post
Taking the equations from

Radiative forcing - Wikipedia, the free encyclopedia

dF=5.35*Ln(C/Co)

dT = 0.8*dF

dF = change in forcing

C = current concentration CO2 (I'm using 2005) 315ppm

Co = orriginal concentration CO2 (I'm using 1958) 380ppm

dT = change in temperature (using 1958 to 2005) 0.64C



I am hoping they made an actual physical measurement and didn't just run that through a model and call it good. This shows that for a doubling of CO2 we get a change of forcing of 3.39w/m^2, which is different from the IPCC value of 3.7w/m^2.

Using the "measured" value changes the equation to

dF = 4.89 * Ln(C/Co)

Filling in for CO2

dF = 4.89*LN(380/315) = .91w/m^2 for the measured 1958-2005 change in CO2.

That should give us a change in temperature of

dT = .8*0.91 = 0.73C which is 0.09C higher than observed.

Correcting for observed gives us a climate sensitivity of 0.696

Now we can calculate for future warming.

Forcasting a rise to 600pmm.

dF = 4.89*Ln(600/315) = 3.15w/m^2

dT = .696*3.15 = 2.19C


That is assuming all warming is due to CO2 with no influence from the sun.
Wiki suggests the size of the sun's effect has not been determined - figures vary between 7% and 16-36% of warming depending on the period.

Solar variation - Wikipedia, the free encyclopedia
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