Since there has been no warming since 1998, the sole repository for alarmist warmism lies in computer models which predict various forms of horror for twenty-first century temperatures. Sorry, I should say super-computer models, since it requires more than just your average huge computer to crunch the numbers representing all the many variables associated with a (warming or not) earth -- it takes several enormous super-computers to even attempt the deed.
And in truth, "attempt" is all that's been done. Despite forecasts for a hundred years of alarmism spewing out of these super-computer models, a recent study determines that not one of the top twenty-two models on which policy-makers rely can be depended on to 'predict' the temperatures for the past one-hundred years.
[Climate scientists David H. Douglass, John Christy, and S. Fred Singer analyzed 22 climate models and found their predictions at odds with actual warming over the past 30 years...
Most of the models predicted significant middle- and upper-troposphere warming, yet actual warming was minimal.
Douglass and his colleagues write, "Model results and observed temperature trends are in disagreement in most of the tropical troposphere, being separated by more than twice the uncertainty of the model mean. In layers near 5 km, the modelled trend is 100 to 300% higher than observed, and, above 8 km, modelled and observed trends have opposite signs."
Not good. A summary of the study by Drew Thornley notes:
Many top climate scientists point out climate models are incapable of handling confounding factors such as cloud cover and water vapor (the dominant greenhouse gas), thus distorting climate predictions.
Additionally, they note, the models do not reflect the actual causes of warming... Singer writes, "Dire predictions of future warming are based almost entirely on computer climate models, yet these models do not accurately understand the role of water vapor. Plus, computer models cannot account for the observed cooling of much of the past century (1940-75), nor for the observed patterns of warming..." Computers, no matter how big, cannot take account of all of the earth's complexities and processes, critics of the alarmist models also note. As a result, no current climate model can explain the causes of climate changes, accurately predict future climate, or form a sound basis for environmental policy.
Policy-makers relying on these models for future policy-making should take note.