Read here. Using actual ocean warming records and comparing those to IPCC climate models was recently accomplished. The purpose of doing so was to determine if model(s) sensitivity would produce predicted warming that matched the actual warming. The determination from the analysis was that the models robustly overestimated ocean warming versus actual - 3.0°C vs 1.3°C.
"The following comparison between the 20th Century runs from most (15) of the IPCC AR4 climate models, and Levitus observations of ocean warming during 1955-1999, further bolsters the case for a relatively low climate sensitivity: estimated here to be about 1.3 deg. C for a future doubling of atmospheric CO2. This is quite a bit lower than the IPCC’s best estimate of 3 deg. C warming...The observed rate of warming of the ocean has been too weak to be consistent with a sensitive climate system. This is demonstrated with the IPCC models themselves...it should be mentioned the above analysis assumes that there has been no significant natural source of warming during 1955-1999. If there has, then the diagnosed climate sensitivity would be even lower still."
Why hasn't the IPCC and the climate modeller community conducted this analysis themselves? Ahhhh....good question with an obvious answer - making failure public is painful.