In what is becoming a continuing series, here is an article by economist Don Boudreaux on how economists are fooled into hubris by their computer models.  It could have been written as easily about climate (emphasis added)

Ironically, however, one genuine sin committed by too many economists is the sin of public hubris — of posing as seers who can divine the details of the future economy, of fooling themselves and the public that economists possess greater knowledge than they really do.

In their papers and books (and now blogs), Keynesian economists model the economy with simple symbols, such as “C” for consumption spending, “I” for investment spending and “k” for the economy’s stock of capital goods such as diesel engines, steel mills and industrial chemicals.

Governments and private researchers gather data on consumer spending, on investment spending and on the market value of all the stuff called “k.” Economists plug these data into computer-based mathematical models filled with “C’s” and “I’s” and “k’s” and other symbols from alphabets both Latin and Greek. These models then spit out precise predictions.

Voila! exclaims the economist slathered in hubris. “See my multivariable model and my precise-to-several-decimal places predictions! I’m a scientist!”

In fact, he’s an alchemist. He is misled — by the intricacy of the equations on his computer screen and by the apparent concreteness of the data that he shoves into those equations — into thinking that he’s doing science. He is misled into thinking that these leaden, aggregated data from the past can be transformed into golden truths about the future.