Climate change: It's the people, stupid!

The BBC reports today on a study that claims to prove that climate change in the Arctic and Antarctic is, in large part, caused by human activities.

The study appears to have invovled running a series of models using known data against assumptions about the effects of human activities. The assumptions ranged from no human effect to significant human effect.

The model than most true to the actual data recorded was the one that assumed humans were the major contributor to polar climate change.

Having been involved in climateprediction.net's modeling work for the past 4 years, I've picked up some of the rationale that makes the outcome of this study not only credible, but convincing. These climate models are now highly refined by years of tweaking and improvement. While they can't "predict" rain in Tokoroa at noon on Tuesday (that being a smaller than microscopic 'eddy' in a vast chaotic system), they certainly can forecast broad trends with considerable accuracy and global climate change is nothing if not a very broad trend.

People unable to understand abstraction will still struggle with this. As one of the scientists involved says:

Professor Phil Jones, director of the Climate Research Unit at the University of East Anglia, said: "Our study is certainly closing a couple of gaps in the last IPCC report.

"But I still think that a number of people, including some politicians, are reluctant to accept the evidence or to do anything about it until we specifically come down to saying that one particular event was caused by humans like a serious flood somewhere or even a heatwave.

"Until we get down to smaller scale events in both time and space I still think there will be people doubting the evidence."

These would be the same sort of people found as empty holes in the ashes of long-buried Pompeii.

"Vesuvius? Deadly? Prove it."

Meanwhile, the Arctic ocean ice just keeps melting.