A new paradigm for climate adaptation

A core finding of the Working Group II report, receiving plenty of attention in the international press, is that the impacts of climate change - things like melting glaciers and reduced snow cover, an increasing frequency of extreme events, coastal flooding, and ecosystem changes - are already being felt, and will only grow stronger. Few people should be surprised by this message. When it comes to adaptation, by contrast, the messages are more muted. One that does stand out, however, is that «(a) first step towards adaptation to future climate change is reducing vulnerability and exposure to present climate variability» (Summary for Policymakers , p. 23).

Raising the dikes

Based on my own 15 years' experience in adaptation research, I would make the argument even stronger: responding to current climate and climate variability is not just one first step, but so far just about the only step. There are very few cases of people adapting their behavior or their infrastructure for the climate they expect in coming decades, rather than the climate they have now. Indeed the only example that comes to mind is also the one that many experts use as the paradigm for adaptation in general, namely the Dutch raising their dikes and widening their flood plains to prepare for sea level rise.

The Dutch have been living below sea level for centuries, and have long ago agreed on a set of infrastructure strategies to protect themselves from the sea, to be undertaken whatever the cost, either in monetary terms or in terms of disruption to the landscape. Where it makes practical or financial sense to plan decades ahead, they do so.

The «best» strategy when uncertainty is high

But the Dutch case is fairly unique. Elsewhere, there is little agreement whether the best coastal strategy is one of hard infrastructure, ecosystem-based barriers and buffers, or managed retreat. The right decision typically depends on how many people will be living near the coast many decades from now, what they will be doing there, and what aspects of the landscape they will most value. Uncertainties in such demographic, social, and psychological factors are huge, typically dwarfing the uncertainties with respect to the future climate. What applies to coastlines also applies to mountains, to forests, to river valleys, to everywhere. In all cases, there are good arguments for restraining some kinds of development in places that appear highly vulnerable to particular climate impacts, but also for taking a wait-and-see approach with respect to costly measures to protect people, their livelihoods, and their settlements.

Adaptation by innovation

A rare exception to a general rule doesn't make a good paradigm. That is the case for the Dutch and their dikes, which suggests taking an existing technology, deploying it more extensively because of the climate we understand to be coming, so that life doesn't get worse. Almost all of the adaptation actually taking place is the complete reverse: it involves applying new innovations to better cope with the climate we already have, so that life gets better.

The innovations come in all shapes and sizes: improved medium-term weather prediction and early warning systems; new models for insurance contracts and finance; seed cultivars that push the envelope on drought tolerance and yield; better pro-active land-use management practices in hazard-prone areas. Together and separately, these can improve human welfare given the climate we have at any given time, now or in the future. And none of them avoid the need to limit climate change in the first place. How we do that is a story for two weeks from now, when the next IPCC Working Group report hits the press.

Prof. Anthony Patt (Quelle: ETH-Zukunftsblog)

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