Wednesday, November 28, 2012

Adapting to a warmer world: No going back

When Superstorm Sandy hit the US coast last month, it blew millions of New Yorkers back into the nineteenth century.

The southern part of Manhattan went black after floodwaters shorted out electrical systems. With the subway system disabled, many residents resorted to traversing the island by foot, and water supplies in some areas became contaminated with bacteria and pollutants.

The largest Atlantic hurricane on record, Sandy wreaked US$50 billion in economic losses along the US northeast coast, providing a costly reminder of how ill-prepared even the richest nations are for weather extremes. Some recent weather disasters have now been attributed, at least in part, to human activity, including the 2003 European heatwave1 and the floods in England in 2000 (ref. 2). According to the Intergovernmental Panel on Climate Change (IPCC), storms, floods and droughts will strike more frequently and with greater strength as the climate warms3. And if nations are struggling to cope now, how will they manage in a warmer, harsher future?

Just a decade ago, 'adaptation' was something of a dirty word in the climate arena — an insinuation that nations could continue with business as usual and deal with the mess later. But greenhouse-gas emissions are increasing at an unprecedented rate and countries have failed to negotiate a successor to the Kyoto Protocol climate treaty. That stark reality has forced climate researchers and policy-makers to explore ways to weather some of the inevitable changes.Nature special:nature.com/kyoto

“As progress to reduce emissions has slowed in most countries, there has been a turn towards adaptation,” says Jon Barnett, a political geographer at the University of Melbourne in Australia.

Adaptation has tended to focus on hard defences, such as shoring up sea walls and building dams. But as awareness of adaptation has grown, so too has the concept. “Adaptation means different things to different people, and is extremely location specific,” says Neil Adger, an environmental and economic geographer at the University of Exeter, UK. Although residents in Bangladesh can raise their houses on stilts to survive floods, some settlements in Alaska and the Maldives must move in the face of rising sea levels. More