Cooling of the Multidecadal Cyclic GMST until about 2030’s suggests La Nina conditions will dominate in the next twenty years.
Guest post by Girma Orssengo, PhD
IPCC’s climate model prediction for a global warming of about 0.2 deg C per decade for the next two decades is contrary to the observed climate pattern.
In the following graphs that show climate data analysis results, the Observed Global Mean Surface Temperature (GMST) shown in Graph “a” has an oscillating Residual GMST of +/- 0.2 deg C as shown in Graph “b”, and a Multidecadal Cyclic GMST of +/- 0.1 deg C as shown in Graph “e”.
As a result, because of these two oscillating components of the Observed GMST, it is incorrect for the IPCC to claim a constant warming rate of 0.2 deg C per decade that lasts for two decades.
Note that for the parameters of the model given in Equation 1, the Residual GMST from 1885 to 2011 shown in Graph “b” has zero mean and zero trend. The result shown in Graph “e” indicates the cooling of the Multidecadal Cyclic GMST until about 2030s. This result suggests La Nina conditions will dominate in the next twenty years. Finally, Graph “f” demonstrates there was no change in the climate pattern before and after mid-20th century, contrary to IPCC claim.
Observed GMST (Graph a) = Residual GMST (Graph b) + Model Smoothed GMST (Graph c)
Model Smoothed GMST = a*Cos[2*Pi*(Year-1910)/60] + b*(Year-1910)^2 + c*(Year-1910) + d
Where a = -0.1050, b = 3.598*10^(-5), c = 3.27*10^(-3), d = -0.345 (Equation 1)
Secular GMST = b*(Year-1910)^2 + c*(Year-1910) + d (Equation 2)
MultiDecadal Cyclic GMST = a*Cos[2*Pi*(Year-1910)/60] (Equation 3)