The major NASA and IPCC climate models, that policymakers have poured billions into, continue to consistently overestimate global warming - this complete lack of predictive skill in regards to global temperatures has literally been mind-boggling bad
(click on images to enlarge)
Both charts reveal dismal predictive skills by these expensive, powerful and complex computer models. Clearly, the models' outputs, based on the existing 'business-as-usual' CO2 emissions, have predicted significant global warming that has not happened. In general, the models have been essentially wrong for an extended period. (Black dashed/dotted intersecting lines on the two charts indicate what these models predicted for the 2011-2012 period.)
These CO2-centric models suffer from a few mission-critical programming errors, based on incorrect assumptions from a green-activist agenda. Specifically, these computer simulations have been programmed to have a very high sensitivity to CO2 levels. These models assume that as atmospheric CO2 levels increase from human CO2 emissions, that global temperatures will rapidly increase to an "accelerating" mode. This key green "science" assumption, and the resulting climate sensitivity programming error, thus produces almost guaranteed failed predictions for future climate scenarios.
In contrast, the rightmost chart represents a newer climate model approach based on harmonics. It appears to produce predictions that are more in touch with known climate reality. The most recent global temperature trends and variations are well within this model's projections.
The 'harmonic' model basically ignores CO2 levels and emissions, instead focusing on astronomical forces, primarily solar system planetary motions.
As a result, the harmonic model better matches the known climate decadal and multi-decadal oscillations that create the global climate variations that are well documented throughout history. The CO2-centric models are totally incapable of doing the same. Obviously, only time will tell if this different approach to climate modeling will continue to have acceptable predictive skills.