Major Climate Report Describes a Strong Risk of Crisis as Early as 2040

Major Climate Report Describes a Strong Risk of Crisis as Early as 2040


https://www.nytimes.com/2018/10/07/climate/ipcc-climate-report-2040.html

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The report, issued on Monday by the Intergovernmental Panel on Climate Change, a group of scientists convened by the United Nations to guide world leaders, describes a world of worsening food shortages and wildfires, and a mass die-off of coral reefs as soon as 2040 — a period well within the lifetime of much of the global population.

The report “is quite a shock, and quite concerning,” said Bill Hare, an author of previous I.P.C.C. reports and a physicist with Climate Analytics, a nonprofit organization. “We were not aware of this just a few years ago.” The report was the first to be commissioned by world leaders under the Paris agreement, the 2015 pact by nations to fight global warming.


The report was written and edited by 91 scientists from 40 countries who analyzed more than 6,000 scientific studies. The Paris agreement set out to prevent warming of more than 3.6 degrees above preindustrial levels — long considered a threshold for the most severe social and economic damage from climate change. But the heads of small island nations, fearful of rising sea levels, had also asked scientists to examine the effects of 2.7 degrees of warming. Absent aggressive action, many effects once expected only several decades in the future will arrive by 2040, and at the lower temperature, the report shows. “It’s telling us we need to reverse emissions trends and turn the world economy on a dime,” said Myles Allen, an Oxford University climate scientist and an author of the report.


The report attempts to put a price tag on the effects of climate change. The estimated $54 trillion in damage from 2.7 degrees of warming would grow to $69 trillion if the world continues to warm by 3.6 degrees and beyond, the report found, although it does not specify the length of time represented by those costs. The report concludes that the world is already more than halfway to the 2.7-degree mark. Human activities have caused warming of about 1.8 degrees since about the 1850s, the beginning of large-scale industrial coal burning, the report found. The report details the economic damage expected should governments fail to enact policies to reduce emissions. The United States, it said, could lose roughly 1.2 percent of gross domestic product for every 1.8 degrees of warming.


At 3.6 degrees of warming, the report predicts a “disproportionately rapid evacuation” of people from the tropics. “In some parts of the world, national borders will become irrelevant,” said Aromar Revi, director of the Indian Institute for Human Settlements and an author of the report. “You can set up a wall to try to contain 10,000 and 20,000 and one million people, but not 10 million.”


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