In the below TED talk, Gavin Schmidt of NASA explains, clear as a bell, why global climate change models mirror, with ever greater accuracy, what we actually observe on Earth. It has to do with a trial-and-error process of calibrating models to new observations. Whenever the models aren’t in the ballpark of an observation, they’re tweaked so that, statistically, they’re more likely to track that observation in the future. The result is that, each year, the models and the actual climate we observe have been converging. Given adjustments and new computer code being added to the models constantly, climate scientists are becoming ever more accurate in their predictions. Put another way, the sustained brain power being devoted to these models, and the reality testing at work all along the way, should give the lay person a high level of confidence that climate scientists have not called the global warming trend in the wrong direction. There’s simply no good reason to dismiss climate change modelling and prediction as delusional, especially going forward.
Prometheus Unbound 