The past decade has been a very significant period in relation to floods around the world, for several reasons. 1 Firstly, some of the most extensive, damaging and costly floods have occurred in developed, wealthy countries: for example, in 1993 in the Mississippi basin (including its major tributaries, the Missouri and Red River) and on the Rhine and its tributaries; in 1998 and 2000 in England; in 1990 in Australia, where an area twice the size of Texas was under water; and in parts of eastern and central Europe in 1997, 1998, 1999, 2000 and worst of all in 2002. While these countries have never been exempt from floods, the severity of these disasters seemed to shock not only the victims, but also governments, planners and insurers. It was as if wealth, infrastructure and order were being unfairly challenged by nature, in societies that considered themselves immune or robust, unlike the less developed countries (LDCs).
Secondly, flooding in LDCs has appeared to be increasingly frequent and serious, to the extent that supposedly 100-year floods were occurring almost yearly in Bangladesh and China, and severe floods afflicted south-east Asia over several years (especially 1996, 1998, 1999 and 2000) and Africa, including Mozambique and Malawi (2000), Ethiopia and Somalia (1997). Thirdly, such floods (rightly or wrongly) have become increasingly associated with climate change: the popular and media perception has been of an increased frequency of floods and storms supposedly resulting from global warming. This general outlook has been linked to a more specific belief that the El Niño Southern Oscillation (ENSO) is increasing in frequency and intensity as a part of climate change. Indeed, such is the popular adoption of El Niño as a climate change phenomenon that it has become a part of television weather forecast in the USA and Europe in the past ten years. 2 This perception has developed alongside increased scientific understanding of ENSO, which has shown it to be not only a regional phenomenon of the Pacific, but part of a system that circumscribes the world, with patterns of