Climate Scientists Encounter Limits of Computer Models, Bedeviling Policy

magzteel writes: From the Wall Street Journal:
As world leaders consider how to limit greenhouse gases, they depend heavily on what computer climate models predict. But as algorithms and the computer they run on become more powerful—able to crunch far more data and do better simulations—that very complexity has left climate scientists grappling with mismatches among competing computer models.

While vital to calculating ways to survive a warming world, climate models are hitting a wall. They are running up against the complexity of the physics involved; the limits of scientific computing; uncertainties around the nuances of climate behavior; and the challenge of keeping pace with rising levels of carbon dioxide, methane and other greenhouse gases. Despite significant improvements, the new models are still too imprecise to be taken at face value, which means climate-change projections still require judgment calls.

“We have a situation where the models are behaving strangely,” said Gavin Schmidt, director of the National Aeronautics and Space Administration’s Goddard Institute for Space Sciences, a leading center for climate modeling. “We have a conundrum.”