General Circulation Climate Models are intended to project (predict) the future climate (global average temperature) based on an assumption of CO2 level growth in the atmosphere
For three reasons I believe accurate predictions are NOT a goal:
(1) Predictions have not been accurate for 40 years -- models consistently over-predict actual global warming,
(2) Predictions have not improved in 40 years, with the latest CMIP6 models (as a group) appearing predict even faster global warming than the CMIP5 models (as a group), and
(3) The one climate model that least over-predicts the global warming trend, the Russian INM model, gets no special attention.
In fact, it is usually buried in an average where ALL the other models over-predict global warming by MORE than the INM model does.
(I can't imagine meteorologists ignoring their best weather forecasting model, and using an average of all models instead).
My conclusion is that climate models are really climate computer games whose primary purpose is to scare people about climate change.
The reality of climate change since humans began adding lots of CO2 to the atmosphere, let's say starting at the trough of the Great Recession in 1932, was some mild warming, and some mild cooling -- NOTHING like the past 64 years of predictions of rapid, dangerous global warming.
The Climate Alarmists claim the gradual increase of the CO2 level will have VERY DIFFERENT effects on the climate in the FUTURE, than it had in the past.
Very different outputs from the same CO2 growth inputs?
That belief meets the definition of insanity, in my opinion -- wild climate speculation, not real climate science.