A new report summarizing the work of 270 climate-change report authors from 67 countries paints a bleak picture of the impact of global heating on nature and people.
Climate Change 2022: Impacts, Adaptation and Vulnerability is the second installment of the Intergovernmental Panel on Climate Change's Sixth Assessment Report.
Today (February 28), the secretary-general of the United Nations, António Guterres, told the media that he's "seen many scientific reports in my time, but nothing like this".
"Today's IPCC report is an atlas of human suffering and a damning indictment of failed climate leadership," Guterres said. "With fact upon fact, this report reveals our people and the planet are getting clobbered by climate change.
"Nearly half of humanity is living in the danger zone now," he continued. "Many ecosystems are at the point of no return now. Unchecked carbon pollution is forcing the world's most vulnerable on a frog march to destruction now."
The facts, according to Guterres, are "undeniable".
"This abdication of leadership is criminal," he added. "The world's biggest polluters are guilty of arson on our only home."
He pointed out that science tells us that to meet a goal of 1.5 ° C average global temperature increase since the start of the Industrial Revolution, it's necessary to cut emissions by 45 percent by 2030 and achieve net-zero emission of greenhouse gases by 2050.
Yet Guterres said that the world is on track for a 14 percent increase in emissions this decade.
"That spells catastrophe," the UN secretary-general said. "It destroys any chance of keeping 1.5 alive."
IPCC reports present scientists' work from around the world and provide summaries for policymakers.
“This report recognizes the interdependence of climate, biodiversity and people and integrates natural, social and economic sciences more strongly than earlier IPCC assessments,” IPCC chair Hoesung Lee said in a news release. “It emphasizes the urgency of immediate and more ambitious action to address climate risks. Half measures are no longer an option.”
The IPCC Working Group II cochair, Hans-Otto Pörtner, said that society can take steps to "accelerate progress towards sustainable development" by "restoring degraded ecosystems and effectively and equitably conserving 30 to 50 percent of Earth's land, freshwater, and ocean habitats".
However, Pörtner added, "adequate finance and political support are essential."
The first installment, released last year, focused on the physical-science basis for climate change. It noted that the scale of recent changes to the climate system is "unprecedented over many centuries to many thousands of years".