25362 – Changes in solar radiance due to 11-year cycles, and other factors are considered in the models. See page 11 of 71 here
On page 29 you’ll see results of temperature trends using model with natural forcings (doesn’t match historical). On page 29 you’ll see results when man-made forcings are added (matches the historical hockey stick graph).
Melone –
Actually with respect to ocean temperatures, the models do better at predicting the long-term behavior than the short term behavior. I have pulled out page 32 of 71 of link above into a 1-page pdf document which is easier to read:
Lcruiser – I have no idea what are the answers to your questions. One would
assume that thousands of the world’s most respected climatologists in the IPCC had a better idea than me, and factored this into their projections and uncertainty statements.
I went back and looked at the Hadley Center’s publication on uncertainy:
It seems like they use a very logical approach to attempt to quantify their uncertainty. They examine how much does changing a certain parameter assumed value affect their results.
But then on page 9 of 16 there is this interesting tid-bit:
The uncertainty results presented in this report are a new refinement in the technique of making climate predictions with complex climate models. Work still remains to investigate the uncertainty caused by changing more of the model’s parameters, including those in the ocean and carbon cycle, or by making large changes in the structure of the model. Before the results are robust enough to be used for planning, it will also be necessary to establish if the more extreme simulated changes are associated with model versions that simulate observed climate well or poorly. The predictions can then be weighted accordingly.
One has to admire them for their candidness, but critics can easily interpret their phrase “before the results are robust enough to be used for planning, it will also be necessary to…” as implying that their results are not yet a suitable basis for planning or taking action. Hmmm.
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