The Wisdom of Crowds Many Models

by F.

From Reuters:

Scientists are trying to improve predictions about the impact of global warming this century by pooling estimates about the risk of floods or desertification.

“We feel certain about some of the aspects of future climate change, like that it is going to get warmer,” said Matthew Collins of the British Met Office. “But on many of the details it’s very difficult to say.”

“The way we can deal with this is a new technique of expressing the predictions in terms of probabilities,” Collins told Reuters of climate research published in the journal Philosophical Transactions of the Royal Society A.

Scientists in the U.N. climate panel, for instance, rely on several complex computer models to forecast the impacts of warming this century, ranging from changing rainfall patterns over Africa to rising global sea levels.

But these have flaws because of a lack of understanding about how clouds form, for instance, or how Antarctica’s ice will react to less cold. And reliable temperature records in most nations stretch back only about 150 years.

Under new techniques looking at probabilities, “predictions from different models are pooled to produces estimates of future climate change, together with their associated uncertainties”, the Royal Society said in a statement.