Panel’s Warning on Climate Risk: Worst Is Yet to Come

Greenland'­s immense ice sheet is melting as a result of climate change.CreditCreditKadir van Lohuizen for The New York Times








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Rajendra K. Pachauri, the chairman of the Intergovernmental Panel on Climate Change, and Christopher Field, the co-chairman of the group that wrote the report, discuss its warning.CreditCreditChristopher Jue/European Pressphoto Agency






Studies have found that parts of the Mediterranean region are drying out because of climate change, and some experts believe that droughts there have contributed to political destabilization in the Middle East and North Africa.

In much of the American West, mountain snowpack is declining, threatening water supplies for the region, the scientists said in the report. And the snow that does fall is melting earlier in the year, which means there is less melt water to ease the parched summers. In Alaska, the collapse of sea ice is allowing huge waves to strike the coast, causing erosion so rapid that it is already forcing entire communities to relocate.

“Now we are at the point where there is so much information, so much evidence, that we can no longer plead ignorance,” Michel Jarraud, secretary general of the World Meteorological Organization, said at the news conference.

The report was quickly welcomed in Washington, where President Obama is trying to use his executive power under the Clean Air Act and other laws to impose significant new limits on the country’s greenhouse emissions. He faces determined opposition in Congress.

“There are those who say we can’t afford to act,” Secretary of State John Kerry said in a statement. “But waiting is truly unaffordable. The costs of inaction are catastrophic.”

Amid all the risks the experts cited, they did find a bright spot. Since the intergovernmental panel issued its last big report in 2007, it has found growing evidence that governments and businesses around the world are making extensive plans to adapt to climate disruptions, even as some conservatives in the United States and a small number of scientists continue to deny that a problem exists.

“I think that dealing effectively with climate change is just going to be something that great nations do,” said Christopher B. Field, co-chairman of the working group that wrote the report and an earth scientist at the Carnegie Institution for Science in Stanford, Calif. Talk of adaptation to global warming was once avoided in some quarters, on the ground that it would distract from the need to cut emissions. But the past few years have seen a shift in thinking, including research from scientists and economists who argue that both strategies must be pursued at once.


The plan is a reaction to the blackouts caused by Hurricane Sandy. Con Ed will raise flood walls, bury some vital equipment and conduct a study of whether emerging climate risks require even more changes. Other utilities in the state face similar requirements, and utility regulators across the United States are discussing whether to follow New York’s lead.






The edit came after several rich countries, including the United States, raised questions about the language, according to several people who were in the room at the time but did not wish to be identified because the negotiations were private. The language is contentious because poor countries are expected to renew their demand for aid this September in New York at a summit meeting of world leaders, who will attempt to make headway on a new treaty to limit greenhouse gases.




The warning about the food supply in the new report is much sharper in tone than any previously issued by the panel. That reflects a growing body of research about how sensitive many crops are to heat waves and water stress. The report said that climate change was already dragging down the output of wheat and corn at a global scale, compared with what it would otherwise be.

David B. Lobell, a Stanford University scientist who has published much of the recent research and helped write the new report, said in an interview that as yet, too little work was being done to understand the risk, much less counter it with improved crop varieties and farming techniques. “It is a surprisingly small amount of effort for the stakes,” he said.

Timothy Gore, an analyst for Oxfam, the antipoverty group that sent observers to the proceedings in Yokohama, praised the new report as painting a clear picture of the consequences of a warming planet. But he warned that without greater efforts to limit global warming and to adapt to the changes that have become inevitable, “the goal we have in Oxfam of ensuring that every person has enough food to eat could be lost forever.”


A picture caption last Monday with the continuation of an article about the latest report by the International Panel on Climate Change misidentified the New York subway station that was shown with flooded tracks after Hurricane Sandy. It is the South Ferry subway terminal, not Grand Central Terminal.