"Humanity is waging war on nature. This is suicidal," U.N. Secretary-General Antonio Guterres said in a speech.U.N. issues dire climate warning: 'The state of the planet is broken'Dec. 2, 202001:40Dec. 2, 2020, 3:48 PM UTCBy The Associated Press

As an extreme year for hurricanes, wildfires and heatwaves comes to an end, the head of the United Nations challenged world leaders to make 2021 the year that humanity ends its “war on nature” and commits to a future free of carbon pollution.

With new reports highlighting 2020’s record-breaking weather and growing fossil fuel extractions that trigger global warming, the U.N. Secretary-General Antonio Guterres delivered another urgent appeal to curb climate change.

It was tinged with optimism but delivered dire warnings, as the U.N. gears up for a Dec. 12 virtual climate summit in France, on the 5th anniversary of the landmark 2015 Paris climate agreement.

“The state of the planet is broken,” Guterres said in a speech at Columbia University. “Humanity is waging war on nature. This is suicidal.”

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“Apocalyptic fires and floods, cyclones and hurricanes are increasingly the new normal,” he said.

In a report, the World Meteorological Organization said this year is set to end about 1.2 degrees Celsius (2.2 degrees Fahrenheit) warmer than the last half of the 1800s. Scientists use this as a baseline for warming caused by heat-trapping gases from the burning of coal, oil and natural gas.

Most trapped heat goes into the world’s seas, and ocean temperatures now are at record levels. It also means 2020 will go down as one of the three hottest years on record.

The Paris climate accord set a goal of not exceeding 1.5-degree (2.7 degrees Fahrenheit) warming since pre-industrial times.

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Guterres saw hope in promises by more than 100 countries that by mid-century they will not be adding more heat-trapping gases to the atmosphere than trees and technology can remove, along with shorter term pollution cuts. While China and U.S. President-elect Joe Biden have pledged net zero carbon emissions.

“I firmly believe that 2021 can be a new kind of leap year — the year of a quantum leap towards carbon neutrality,” Guterres said.

But he added the U.N. reports on Wednesday “spell out how close we are to climate catastrophe.”

When countries spend trillions of dollars to recover from the coronavirus pandemic-triggered economic slowdown, Guterres said they must to do so in a way that emphasizes clean energy.

Nations should also stop funding and subsidizing fossil fuels, he added. And wealthy countries must fulfill their Paris promise to spend $100 billion annually to help poorer countries develop cleaner energy.

Guterres said there was no way the world could curb climate change “without U.S. leadership” and urged students and other Americans to do “everything” possible to get their governments to curb emissions more swiftly.