As the US finally concedes that global warming is happening, dramatic new data is emerging on the impact of "natural" disasters. Neither rich nor poor countries can escape. But the biggest question raised is for the developing world. After a decade of UN conferences designed to end poverty and save the world, disasters driven by global warming are causing catastrophe for the poor majority and political and economic insecurity for the rest.

Although the number of people killed by disasters has fallen by more than half over the past three decades, the number affected - a definition which includes being injured or made homeless - has grown enormously. According to the World Disasters Report, it is up from 740 million in the 1970s to more than two billion in the past decade (these figures include some double counting due to people being repeatedly affected). Reported economic losses, calculated at current values, have risen from $131bn in the 1970s to $629bn in the 1990s. Actual losses are greater. The number of reported disasters rose from 1,110 to 2,742 in the period.

In regions such as Oceania in the past 30 years, the number affected has increased 65-fold. Yet in all the international political efforts to agree targets for reducing poverty and protecting the environment - now focused on the so-called millennium development goals - no one has taken serious account of the increasing impact of disasters. Heads of state will go to Johannesburg this summer to make the millennium goals a reality. They include doubling the proportion of people with access to drinking water by 2015, halving absolute poverty and improving the lives of 100 million slum dwellers by 2020. But without modeling the impact of disasters, this is wishful thinking. The Bangladesh center for advanced studies calculates that every dollar invested in the country is absorbed by the cost of dealing with predictable disasters.

It would also be a mistake for industrialized countries to think they can weather the storms. The disasters boomerang will hit the rich world in a number of ways. Insurance firms are backing away from providing cover to the one in 10 British households prone to flooding. Long-term projections from big insurers, such as CGNU, suggest that the upward curve of economic damage from global warming will overtake gross world product by 2065, effectively bankrupting the global economy. Serious destabilization is likely well before that date. Environmental refugees now outstrip in number political refugees. An estimated 25 million people are displaced by environmental causes, more than double the 12 million political refugees. They are proving such a contentious issue that the UN high commissioner for refugees does not want them to have international legal status requiring protection. Where global warming-driven disasters are forcing people to flee their homes, responsibility falls heavily on rich countries whose greenhouse gas emissions have largely created the problem. Their challenge is to provide financial and technical support, and to create protective status for environmental refugees.

There has been no global assessment of the number likely to be displaced by a rise in sea level of half a meter to one meter, both possible in the foreseeable future. Following such a rise, millions would be displaced in countries across the developing world such as Bangladesh, Nigeria, Egypt and Guyana. At least five island nations would become uninhabitable. These include the Maldives, the Marshall Islands and Tuvalu, which, frustrated by international inaction, are seeking legal assistance to take the world's biggest polluters to court.

There has also been no global assessment of the likely costs to poor countries incurred by the need to adapt to global warming. Being better prepared can make a huge difference. Two million lives were saved in the 1990s in Bangladesh through coordinated evacuations. But it is no longer sufficient to leave disaster management to the specialists. Global warming means a whole new way of thinking is necessary.

Andrew Simms is policy director of the New Economics Foundation and co-author of the World Disasters Report 2002, published by the International Federation of the Red Cross and Red Crescent Societies

© Guardian Newspapers Limited 2002

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