Meio Ambiente: o ambientalista cetico e a conferencia de Durban

Global Warming and Adaptability

Any carbon deal to replace Kyoto would have a negligible impact on climate in coming decades.

By BJØRN LOMBORG

The Wall Street Journal, December 12, 2011

The Durban pit-stop in the endless array of climate summits has just ended, and predictably it reaffirmed the United Nations' strong belief that the most important response to global warming is to secure a strong deal to cut carbon emissions.

What is almost universally ignored, however, is that if we want to help real people overcome real problems we need to focus first on adaptation.

The Durban agreement is being hailed as a diplomatic victory. Yet it essentially concedes defeat, leaving any hard decisions to the far end of the decade when other politicians will have to deal with it. For nearly 20 years, the international community has tried to negotiate commitments to carbon cuts, with almost nothing to show for it.

Even most rich countries don't want to cut fossil fuels, because the alternatives are considerably more expensive. China, India and other emerging economies certainly do not want to, because putting the brakes on growth means consigning millions to poverty.

But even if such intractable issues could be magically resolved, any deal would have a negligible impact on climate. Even if we were to cut emissions by 50% below 1990-levels by 2050—an extremely unrealistic scenario—the difference in temperature would be less than 0.2 degrees Fahrenheit in 2050.

This goes against everything that carbon campaigners tell us. When Hurricane Katrina or other weather disasters devastate communities, we're told by advocates such as Al Gore that the effects of climate change are already being felt and it's time to commit to drastic carbon cuts.

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It is worth noting that often these arguments are exaggerated for effect. Since Hurricane Katrina, the global accumulated cyclone energy index has declined to almost the lowest level since we started measuring such phenomena in the early 1970s. Global warming will probably make hurricanes slightly stronger but slightly less frequent, leaving the overall impact murky.

What we can say clearly is that if we want to help New Orleans or other at-risk areas, cutting emissions will have virtually no impact for many decades. Bolstering hurricane defenses through improved levees and wetlands could, however, make a world of difference.

This is even more true for hurricane impacts in Third World countries. When Hurricane Andrew hit Florida, it cost 10% of the state's GDP and killed 41 people. But when the similar-sized Hurricane Mitch hit Honduras, it cost the country two-thirds of its GDP and killed more than 10,000. Tackling hurricane impacts in developing countries is not about cutting carbon but about adaptation and economic growth to improve resilience.

This is true whether we look at hurricanes or at other problems exacerbated by global warming. It is often—correctly—pointed out that global warming will hit developing countries hardest. Malaria cases, for instance, will increase along with mosquito populations, while food production in many developing countries will decrease.

But getting an emissions deal in any of the future Durban meetings will do nothing to help either of these problems. Even if we halted global warming by the end of the century, we could expect to avoid only about 3% of world-wide malaria cases by 2100. What the billions afflicted by malaria in the world today need is access to treatment and better prevention through bed-nets and indoor spraying. This is adaptation.

When it comes to access to food, global warming is expected to be responsible for a 7% yield decrease in the developing world and a 3% yield increase in the developed world over this century. Yet this needs to be seen in the context of total developing world food production rising by about 270% over the same period.

Do we better help the developing world by making drastic carbon cuts today that might—in an ideal world—avoid a 7% yield drop, or by making higher-yielding varieties of crops available that could potentially generate drastic yield increases? These are questions we have to answer if we are to adapt to the reality of global warming in this century.

The first step in focusing on adaptation is measuring it. The Global Adaptation Institute, led by former World Bank Managing Director Juan Jose Daboub, publishes the Global Adaptation Index, which shows how vulnerable countries are to global warming and how prepared they are to tackle it. The challenge lies not merely in reducing vulnerability but also in getting the structures in place so governments and investors can tackle adaptation in the most effective manner possible. The good news is we can improve lives today while building the crucial infrastructure needed for tomorrow.

The climate will continue changing throughout this century. And we do need to fix carbon emissions smartly through technological innovation. But if our concern is with saving lives and helping the planet's most vulnerable populations, then we need to focus first on how we can build more resilient, adaptable communities.

Mr. Lomborg is the author of "The Skeptical Environmentalist" and "Cool It." He directs the Copenhagen Consensus Center and is an adjunct professor at Copenhagen Business School.