CET vs Bruce's model
Ta = A + B + C + D (+ E)
where:
A = f(pCO2) = 0.8656*LN(pCO2 in ppmV)-4.8776 [derived from a 2XCO2 of 0.6 C]
B = f(oceancycles) = 0.135*SIN(((Year-1922)/(65/2))*PI()) [see link 1]
C = f(pSCL in years) = -0.4778*pSCL+5.2679 [see link 2]
D = CET average anomaly – baseline 1961-1990 anomaly = -0.1492
Optionally you can add a factor for the intra solar cycle temperature variation:
E = (annual av sun spot number – solar cycle av sun spot number)/150
The factor “E” is normalised so that it adds up to zero over each solar cycle, therefore it doesn’t affect the overall trend.
Link 1 = digitaldiatribes.wordpress.com/2010/07/15/the-best-of-dig...
Link 2 = Butler & Johnson 1996 (slope of Armagh graph...which is similar climatically to the CET triangle)
If you leave out the ocean cycles (B) and determine A by goalseek in Excel the 2XCO2 comes out very close to 0.7 C/doubling. This is consistent with S&B 2010 and L&C 2011 but not with the IPCC range of 2 - 4.5 C/doubling.
This analysis was my attempt to independently check the competing claims of the low sensitivity hypothesis vs the IPCC's high sensitivity hypothesis. As you can see the former fits the data best.