The world’s nations must commit to dramatically slashing greenhouse gas emissions in the near future or risk a “catastrophic” rise in global average temperatures, a key United Nations climate report published Thursday warned.

“It is still technically possible to meet the 1.5°C goal” set out in the Paris agreement, “but only with a G20-led massive global mobilization to cut all greenhouse gas emissions, starting today,” the United Nations Environmental Program (UNEP) said in a summary of its annual Emissions Gap Report.

“Nations must collectively commit to cutting 42% off annual greenhouse gas emissions by 2030 and 57% by 2035 in the next round of Nationally Determined Contributions (NDCs)—and back this up with rapid action—or the Paris agreement’s 1.5°C goal will be gone within a few years,” UNEP warned.

“Failure to increase ambition in these new NDCs and start delivering immediately would put the world on course for a temperature increase of 2.6-3.1°C over this century,” the agency said. “This would bring debilitating impacts to people, planet, and economies.”

UNEP said “solar, wind, and forests” have […]