- Human activities “unequivocally” cause climate change
- World expected to reach 1.5 Â° C warming limit within 20 years
Aug. 9 (Reuters) – The UN panel on climate change issued a stark warning on Monday, saying the world is dangerously close to uncontrollable warming – and that humans are “unequivocally” to blame.
Already, levels of greenhouse gases in the atmosphere are high enough to guarantee climate change for decades, if not centuries, scientists warn in a report by the Intergovernmental Panel on Climate Change (IPCC ).
This is in addition to the deadly heat waves, gigantic hurricanes and other extreme weather events that are happening now and are likely to get worse.
Describing the report as a “code red for humanity,” UN Secretary-General AntÃ³nio Guterres called for an end to the use of coal and other highly polluting fossil fuels. Read more
“The alarm bells are deafening,” Guterres said in a statement. “This report must spell the end of coal and fossil fuels, before they destroy our planet.”
The IPCC report comes just three months before a major United Nations climate conference known as COP26 in Glasgow, Scotland, where nations will be under pressure to commit to much more ambitious climate action and to substantial funding to support it.
Drawing on more than 14,000 scientific studies, the report provides the most comprehensive and detailed picture yet of how climate change is altering the natural world – and what may still be to come.
Unless immediate, swift and large-scale action is taken to reduce emissions, the report says, the average global temperature is expected to exceed the warming threshold of 1.5 degrees Celsius (2.7 degrees Fahrenheit) over the years. Next 20 years.
So far, pledges from nations to cut emissions have been insufficient to bring down the level of greenhouse gases accumulated in the atmosphere. Read more
Governments and activists have reacted to the findings with concern.
British Prime Minister Boris Johnson, whose country will host the climate conference, said the next decade will be “pivotal” in securing the future of our planet:
“I hope today’s IPCC report will be a wake-up call for the world to act now, before we meet in Glasgow in November for the crucial COP26 summit.”
Emissions “unequivocally caused by human activities” have already raised the average global temperature by 1.1 Â° C above its pre-industrial average – and would have increased it further by 0.5 Â° C without the moderating effect of air pollution, according to the report.
This means that even if societies move away from fossil fuels, temperatures will again be raised by the loss of these air pollutants.
Scientists warn that a rise of more than 1.5 Â° C above the pre-industrial average could trigger uncontrollable climate change with catastrophic impacts, such as heat so intense that people die simply because they are outside.
Any further warming will also increase the intensity and frequency of extreme heat and heavy rainfall, as well as droughts in some areas. Because temperatures fluctuate from year to year, scientists measure global warming in terms of 20-year averages.
“We have all the evidence we need to show that we are in a climate crisis,” said Sonia Seneviratne, three-time IPCC co-author and climate scientist at ETH Zurich, who doubts she will sign for one. fourth report. âPolicymakers have enough information. You may ask: is this a significant use of scientists’ time if left unchecked? “
The 1.1 Â° C warming already recorded was enough to trigger disastrous weather. This year, heat waves killed hundreds of people in the Pacific Northwest and broke records around the world. Heat and drought-fueled wildfires are sweeping entire cities across the western United States, releasing record-breaking carbon dioxide emissions from Siberian forests and causing Greeks to flee their homes by ferry.
“Every element of warming matters,” said IPCC co-author Ed Hawkins, a climatologist at the University of Reading in Britain. “The consequences are getting worse as we warm up.”
The Greenland ice sheet is “virtually certain” that it will continue to melt and raise sea levels, which will continue to rise for centuries as the oceans warm and expand.
It is already too late to prevent these particular changes. The best the world can do is slow them down so that countries have more time to prepare and adapt.
“We are now engaged in some aspects of climate change, some of which are irreversible for hundreds to thousands of years,” said Tamsin Edwards, co-author of the IPCC, climatologist at King’s College London. “But the more we limit warming, the more we can avoid or slow down these changes.”
“WE STILL HAVE CHOICES TO MAKE”
Even to slow climate change, according to the report, the world is running out of time.
If the world significantly reduces its emissions over the next decade, average temperatures could rise another 1.5 Â° C by 2040 and possibly 1.6 Â° C by 2060 before stabilizing.
If the world does not significantly reduce emissions, but continues on the current path, the rise could be 2.0 Â° C by 2060 and 2.7 Â° C by the end of the century.
The land hasn’t been this hot since the Pliocene epoch around 3 million years ago – when mankind’s first ancestors appeared, and the oceans were 25 meters (82 feet) higher than they are not today.
It could be even worse if warming triggers feedback loops that release even more climate-warming carbon emissions, like melting arctic permafrost or dying out of global forests. In these high emission scenarios, the Earth could roast at temperatures 4.4 Â° C above the pre-industrial average by 2081 to 2100.
“We have already changed our planet, and some of those changes that we will have to live with for centuries and millennia to come,” said Joeri Rogelj, IPCC co-author, climatologist at Imperial College London.
The question now, he said, was how many irreversible changes could be avoided.
âWe still have choices to make.
Reporting by Nina Chestney in London and Andrea Januta in Guerneville, California; Additional reporting by Jake Spring in Brasilia, Valerie Volcovici in Washington and Emma Farge in Geneva; Editing by Katy Daigle, Lisa Shumaker and Kevin Liffey
Our Standards: Thomson Reuters Trust Principles.