Climate-Model Misgivings

OXFORD – The credibility of climate scientists has taken a number of hits lately, with climate models having failed to predict the “pause” in global warming over the last decade or last year’s increase in Antarctic sea ice. Even with the benefit of hindsight, the Intergovernmental Panel on Climate Change has struggled to explain recent developments.

This is more than embarrassing; it is cause for serious concern. After all, arguably the most important issue in climate science today is not whether man-made global warming is real, but whether the models being used to predict climate change are reliable enough to inform policymakers’ decisions.

Of course, no one is suggesting that climate scientists should be able to predict future developments precisely. Even tomorrow’s weather forecast – produced using techniques that form the basis of climate models – is not 100% accurate. But weather forecasts are becoming increasingly precise – and climate predictions should be following suit.

Weather forecasts are generated from results produced by supercomputers, which solve the fundamental physical equations. In a process called data assimilation, each forecast blends the previous one with new data about the state of the atmosphere from satellites, weather radar, and ground stations.