Amazon Experts Cautious on Climate Threat

Amazon Experts Cautious on Climate Threat, by Andrew Revkin
Dot Earth/TNYT, April 7, 2009, 2:54 pm

The lure of the “front-page thought” — for both scientists and the press — was very much on display at the recent Copenhagen summit on climate change. Presentations and speeches were followed by a wave of coverage, primarily in Europe, focused on what many papers said was strong new evidence of pending climate calamity.

Some scientists who attended the meeting pushed back. Mike Hulme of the University of East Anglia criticized efforts to cast the six-point manifesto released at the meeting’s end as the product of a broad consensus (simultaneously published on the Prometheus blog). Other scientists, who study facets of how global warming could affect things that matter — in particular the Amazon rain forest — criticized what they saw as overstatements coming out of the meeting and have now followed up afresh.

Yadvinder Malhi, a professor of ecosystem science at the University of Oxford, and Oliver Phillips, a professor of tropical ecology at the University of Leeds, have written a response to a story in the Guardian on a modeling study that projected that the Amazon forest was poised to die off. The scientists contend in a response published today in the paper that the single study, not yet peer reviewed, was laced with uncertainties downplayed both by the scientists describing it and the resulting news story.

(Dr. Malhi also contributed to my recent article assessing what is, and isn’t known, about possible tipping points related to global warming.)

Here’s the take-home point from Dr. Malhi and Dr. Phillips:

Forest dieback is a possibility that should not be ignored, and the probability increases with increasing air temperatures; but it is not inevitable. What is clear is that climate change magnifies the threat from advancing agricultural development, as a drier Amazon will burn more easily….

Climate change is undeniably a serious threat, and our comments should not be seized upon as an excuse for delay or inaction. Rather, conserving Amazonian forests both reduces the carbon dioxide flux from deforestation, which contributes up to a fifth of global emissions, and also increases the resilience of the forest to climate change. The potential impacts of climate change on the Amazon forest must be a call to action to conserve the Amazon, not a reason to retreat in despair.