Dominick Chilcott

The danger and science of flooding

Last week, Prof. John Beddington, the British Government's Chief Scientific Advisor, was the guest of honour at a reception in the British Embassy for participants in a seminar on tackling the threat from flooding. You could be forgiven for thinking this was run of the mill diplomatic activity - a reception, a visiting British VIP, a serious topic of public policy. Doubtless, all very worthy but why should anyone else give a gnat's whisker about it? Well, let me try to engage your attention.

If you'll forgive the pun, flooding, as an issue, is on the rise around the world. As people get more affluent and populations rise, we are demanding more land for houses, roads, new shops and other buildings. In a small-medium sized country like Britain, the amount of land available is limited. So we have been forced to build in places where there is a greater risk of flooding.

At the same time, climate change is contributing both to rising sea levels (as polar ice, mountain snow and glaciers melt) and to more storms. This year Gustav and Ike have wreaked great damage. And Katrina remains a painful memory for many. The number and severity of hurricanes and tropical storms seems, anecdotally, to be rising.

The science points to the same conclusion. According to the UN's Intergovernmental Panel on Climate Change (2007 Fourth Assessment Report), hurricanes have become more intense since the 1970s. The IPCC judge that it is "more likely than not" that there is a human contribution to this trend. In the future, they think "it is likely that future tropical cyclones (typhoons and hurricanes) will become more intense, with larger peak wind speeds and more heavy precipitation associated with ongoing increases of tropical sea surface temperatures."

These storms are likely to do even more damage in future because, with higher sea levels come bigger surges of water, more likely to breach sea defences. At the same time, coastal ecosystems, such as barrier islands and wetlands, are continuing to degrade. So just when our need for these natural sea defences is rising, we are increasing our vulnerability to the massive waves that severe hurricanes bring.

So we have been warned. In fact, the threat from flooding is now taken so seriously that facing up to it features in government national security strategies the world over.

It was against that background that the British Government set up the Foresight Flood and Coastal Defence Project, commissioned by Professor Beddington's predecessor, Sir David King. All parts of government concerned with flooding and the country's best geographers, scientists and other academics working in the field took part. The ambitious aim was to evaluate how the risks from flooding were likely to change in the next 30-100 years as a result of climate change and direct human activity such as building and land use. In Sir David King's words, it was "the most wide-ranging analysis of future flood risk ever made in the UK".

In April 2004, the project published its findings. It estimated that the cost of damage from flooding and coastal erosion in Britain could rise by 20 times over the next century. In the most extreme scenario and with existing defences, the damage could rise from about $2bn a year now to $40bn by 2080. The study called for a steady increase in spending on flood defences and better planning to avoid more homes being put at risk.

And here's the good bit. Because all relevant parts of government had taken part in the project and because it was the most thorough, serious and scientific assessment of the risks, particularly the risks of not taking more decisive action now, the British government responded by doubling the funding for flood protection. The Treasury bought the compelling argument that it was wise to invest now to prevent paying huge bills later.

The methodology of the Foresight Flood and Coastal Defence Project is perhaps as interesting and useful as the findings themselves. Getting disparate parts of government to come together and take a common view on any subject, even one as serious as flooding, can be complicated and frustrating. But it is probably necessary if governments are to put in place the funding and programmes that are needed to protect us in future.

Time will tell whether this experience is regarded as relevant and interesting in the United States. Certainly, government here can appear mind-bogglingly complex. But if the British experience catches on, then last week's reception with Professor Beddington may have made a small contribution to helping this country protect itself against future Katrinas, Ikes and Gustavs.

Posted at 15:14 25 September 2008 by Dominick Chilcott  |  Comments[0]