Tuesday, March 15, 2005

An old quote, but a good one

What some call health, if purchased by perpetual anxiety about diet, isn't much better than tedious disease.

George Dennison Prentice

Eruption of fear

'A true story that hasn't happened yet', intones the trailer for the BBC drama Supervolcano. In the mini-series, a volcano in Yellowstone erupts, covering North America in ash and inducing global cooling. On the back of the series, scientists have warned that we need to be prepared for this kind of disaster. A report by a Geological Society working group notes: 'An area the size of North America can be devastated, and pronounced deterioration of global climate would be expected for a few years following the eruption. They could result in the devastation of world agriculture, severe disruption of food supplies, and mass starvation. These effects could be sufficiently severe to threaten the fabric of civilization.'

Professor Stephen Self of the Open University says: 'We don't want to be sensationalist about this, but it's going to happen. We just can't say exactly when. But we have just had a natural disaster affecting hundreds of thousands of people. Now is the time to be thinking about this.'

This is an example of a Really Bad Thing that could happen in our lifetimes but is highly unlikely to. While major volcanic eruptions occur somewhere in the world every few years, these are much smaller than the kind of event described in Supervolcano, which appears to occur on average about every 50,000 years.

But what programmes like this do produce are some really bad pieces of logic. For example, the accompanying documentary, part of the Horizon series, tells us: 'Scientists have revealed that [Yellowstone] has been on a regular eruption cycle of 600,000 years. The last eruption was 640,000 years ago...so the next is overdue.' Perhaps that eruption cycle isn't so regular after all....

One thing is clear: there's nothing we could do to stop such an explosion occurring, so there is simply no point in worrying about it. It might keep a working party or two gainfully employed fretting about how we might cope, but that's about it. Moreover, it is wrong to assume that society could not survive such an event. Unlike the dinosaurs, we can control our environment - produce our own sources of power, find alternatives methods of producing food, and so on. We are not helpless victims of nature.

In the meantime, there are lots of very real problems that are within our means to control, such as malaria, access to clean water and general poverty. The more society develops, the better able we are to cope with the occasional shock.

Classic Hollywood disaster movies were about putting yourself in the place of the hero and wondering how you'd cope with being in a sinking cruise liner, burning skyscraper, failing airplane, or even a town struck by a volcanic eruption. The crisis was purely a device to create a dramatic situation. But no disaster movie these days is complete without the 'real science' behind it. Supervolcano, like The Day After Tomorrow, hitches its plot to real ecological concerns in order to grab our attention. But 'a true story that hasn't happened yet' is not a true story. It's a wind-up.

The suggestion that there is a real and pressing problem behind the fiction feeds off and reinforces a more generalised fear of the future. It also encourages scientists to over-egg their research to grab the media limelight. It's time to untangle science and fiction: the only thing disaster movie fans should be fretting about in real life is the price of popcorn.

Experts weigh supervolcano risks, BBC News, 9 March 2005

Supervolcano, BBC

Super-eruptions: global effects and future threats, Geological Society of London