No two-snouted pigs for you today! Today’s topic is everybody’s favorite subject - the weather - and even better - climate change.

The picture above is from the 2005 UN Climate Change Conference. Have you noticed how it seems like every year recently is the hottest or coldest on record, wettest or driest? They’re predicting that this trend will continue, and they’re using these charts to represent their forecasts of what areas of the Earth will see the most extreme weather.

This is all well and good, but then they go and say: “We hope it will help policy-makers gain a quick overview of the scientific facts without getting lost in the detail.”

Before I say this, let me get this out of the way: I believe that the Earth’s climate is changing, but I believe that the climate changes naturally. I believe it is possible that the climate is changing in response to human technology, but I don’t believe that this is necessarily a given. And discussions about climate change are generally about politics rather than science. I’m not going to talk politics here. I am not anti-climate change. In fact, part of me thrills to the possibility. But I am also not simply accepting human-driven climate change as fact.

And “fact” is where the problem lies in the UN statement.

Facts are observations. They’re provable. They’re testable.

We don’t know an awful lot of facts about the year 2100. There are some predictions we can make with greater or lesser confidence. We can predict, with such high confidence that we might decide to call it a fact, that the Earth will still be zinging around the sun in 2100. That the sun will be acting roughly the way it is now in 2100. That the composition of the Earth will be roughly the same - oceans, continents, atmosphere, crust, etc.

When we start forecasting dynamic systems such as climate and weather, we’re talking about theories. The facts in these cases are observations: we may say that the temperature in the Arctic has risen by a certain amount, that an ancient ice shelf has broken off, that a certain glacier’s size has diminished, or that there were more Category 4 storms one year than another.

The forecasts - theories - are testable, but they haven’t been tested and can’t have been tested until the time they forecast for has passed, and it is irresponsible to present them as “fact”. This is the kind of scientific misconduct which fuels distrust of science. Sure, saying it’s a “fact” sounds better, more serious, and frankly is more dramatic, and you may believe it with all your heart, but that doesn’t make it a fact.

And - in fact - I may be conducting blogger misconduct here by unintentionally taking this quote out of context. In the context it’s in in the article I read, it appears to be applied to the forecasts of extreme weather. If it’s simply being applied to climate observations already made then my complaints about it are likely out of line, but my general statements about fact and theory are not.

Via: 2100: A world of wild weather - earth - 18 January 2007 - New Scientist Environment
[tags]weather, climate change, 2100, science, facts[/tags]

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