Saturday, November 17, 2007

Climate Change is Here to Stay - Learn to Live with It!

The only way to adapt to global climate change is with risk management strategies based on solid geographical understanding. The evidence of manmade climate change is overwhelming. Although global climate has always fluctuated dramatically and it is difficult to say what part of our current warming trend is due to natural causes, the majority of scientists believe that human activities are contributing to this change. While we need to work towards mitigating climate change in the long run, it is already too late to halt the process. We need to learn to adapt to the changing conditions.

The problem is that there is considerable uncertainty about how climate change will manifest itself in specific geographical locations. The interlinkages and feedback loops are so complex that even sophisticated computer models cannot produce firm predictions. Climate change is easy to ignore by the politicians and public alike, because of the uncertainty of its outcomes and its gradual nature. The uncertainty should not be used as an excuse for inaction. When we finally decide to react, it may be too late. We must manage its risks, especially when undertaking new large projects, be they dams, airports, or new highway systems.

The popular name for climate change – global warming – is an unfortunate misnomer. It is not that global warming will make every place warmer. The impacts will neither be uniformly negative: there will be winners and losers. Some present-day deserts may receive more rainfall thus making them green. Or the warmer climes may or may not benefit some countries at high latitudes. But in many places the impact will be increasingly unpredictable and extreme weather.

Neither will climate change affect only the developing world or small islands sinking into the rising seas. Low-lying coastal areas everywhere – from the Mississippi delta to the Netherlands, from Tokyo to the small island of Manhattan – will be equally threatened by sea level rise and coastal storms.

Coastal cities are the fastest growing places in the US, China and elsewhere. Already now, half of the world’s population lives within 150 km from the coast. It is not hard to imagine the damage and the concomitant costs that ever stronger coastal storms can cause: just witness the aftermath of Hurricane Katrina in New Orleans. But the impacts can be much more varied. Storm surges and sea level rise not only may inundate low-lying coastal areas but can cause saltwater intrusions into groundwater that render water supplies unusable.

Changes in climate may dramatically modify growing seasons or shift agricultural zones so that they no longer can produce as previously. Regional droughts may deplete aquifers. These scenarios have serious implications to our food security. In a globalized economy, local disturbances in food self-sufficiency can have widespread implications as the country or mega-city experiencing food deficits starts buying food on the international market. Prices then can swing unpredictably.

We must have solid geographic knowledge combined with hard-headed risk assessment, and not just for some places. Any new large-scale irrigation project will require an assessment of whether its water resources will still be adequate thirty or fifty years down the line. Major new infrastructure requires massive investment, takes a long time to develop, and is built to last. It is imperative to consider vulnerability when, say, deciding on the location of a new airport. Will it still be there or will it be under water in forty years time? There are numbers of active airport building projects, for example, in South Asia, a hot zone for tropical cyclones. How will they be protected?

Who will bear the costs when properties are damaged by violent natural events? The insurance industry that ends up absorbing many of the losses stemming from hurricanes and other disasters to coastal property is developing geographical expertise to allow it to set insurance premiums based on exposure and vulnerability. But can the vulnerable people afford to pay - or move if necessary - whether they are in South Florida or Sri Lanka? The more gradual the changes, the less likely the need for draconian adjustments.

Risk management strategies based on a thorough geographical understanding of hazards and vulnerability are immediately needed. That means putting together the full range of conditions – things like current and changing topography, vegetation, prevailing winds, water tables, population, buildings, and transportation systems – with the uncertainties of climate change. Any investment that ignores climate change as too costly risks pay a far higher price in the long run.

Juha Uitto 2005

No comments: