Climate debate at crossroads

The United Nations has set up a needed independent review of the International Panel on Climate Change (IPCC), focusing on how known errors got into a 2007 report. But the review will have to go beyond its initial mandate if it wants to remove the cloud that has gathered over the climate change debate in recent months.

According to the New York Times, the review will address how mistakes, including a large exaggeration of the melting rate of Himalayan glaciers, got into the purportedly authoritative summary of scientific studies of the earth's climate. But UN officials said it will not address the basic finding that human activity is accelerating global warming at an increasing rate.

An unauthorized leak last fall of e-mails from the embattled Climate Research Unit at the University of East Anglia in England raised questions about the scientific probity of the research. The issue is being investigated by the British Parliament.

In a statement to the House of Commons Science and Technology Committee, the prestigious Institute of Physics joined other scientific societies in deploring the CRU's refusal to share data with other researchers and said the e-mails raised "doubts as to the reliability" of "the conclusion that 20th century warming is unprecedented."

These doubts don't disprove the argument that increasing levels of carbon dioxide and other "greenhouse gases" are raising world temperatures. But they still raise important questions.

For example, scientists at the University of Alabama at Huntsville who study earth temperatures measured by satellites argued last year that the unquestioned accumulation of carbon dioxide in the atmosphere caused by human activity may have a smaller impact on future world temperatures than predicted by the 2007 IPCC report.

A prudent approach to climate change must continue to focus on reducing the use of fossil fuels where possible. But the limited scope of the new UN study will not dispel doubts that undermine this approach unless it addresses more than the few obvious mistakes in the 2007 IPCC report. It must take on larger questions if it hopes to restore the prestige of climate science.