http://dotearth.blogs.nytimes.com/2009/05/29/warming-and-death/

May 29, 2009, 11:34 AM
Warming and Death
By ANDREW C. REVKIN

There are significant questions about the robustness of the numbers at the heart of the new report estimating more than 300,000 deaths are already being caused each year by global warming, with nearly twice that number possible by 2030. The report was commissioned by the Global Humanitarian Forum, created in 2007 by the former United Nations secretary general Kofi Annan, and reviews reams of data and earlier analysis by other researchers and groups. More on the questions is below.
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Just to offer a capping thought, below you can read how Jeffrey D. Sachs reacted when I asked him about the new report. He's mentioned in the news story but there was no space for more. Dr. Sachs, an adviser to the United Nations and head of the Earth Institute at Columbia University, was on a panel of a dozen outside experts who reviewed the Global Humanitarian Forum report prior to publication.

He said he and other reviewers pressed the authors to stress uncertainties when describing the death count from global warming. "There's no reason to overreach," he said. "I don't think headline numbers that give a sense of precision we don't have are either necessary or helpful. The facts with all the uncertainties are dramatic enough. We're just going to face a growing crisis. From Chad to Sudan, the Ogaden, Somalia, Yemen, Iraq, Pakistan, Afghanistan, this long stretch of drylands is being pummeled by this combination of environmental degradation, including climate instability, together with massive population growth."