UN chief says world on 'highway to climate hell'

The planet is set to warm by more than 1.5 C above its pre-industrial temperature during the coming five years, exceeding targets in the 2015 Paris Agreement and moving us closer to disaster, according to the World Meteorological Organization, or WMO.

A new report from the United Nations agency released to mark Wednesday's World Environment Day says there is an 80 percent probability the global annual average temperature will pass the 1.5 C mark in at least one of the coming five years.

The Paris Agreement had highlighted a 1.5 C rise as something to avoid, and assumed it was decades away. But the WMO said it now looks as if a 1.5 C rise will be here imminently, if only temporarily, and urged nations to take urgent action to reduce greenhouse gases and global warming before it is too late.

UN Secretary-General Antonio Guterres said countries should respond by setting tougher targets, something that will be discussed at a G-7 summit in Italy between June 13 and 15.

"We are playing Russian roulette with our planet," Guterres said. "We need an exit ramp off the highway to climate hell. And the good news is that we have control of the wheel. The battle to limit temperature rise to 1.5 degrees will be won or lost in the 2020s – under the watch of leaders today."

He added that stronger and more specific national climate plans must be unveiled at next year's COP30 climate summit in Brazil.

The WMO report predicts the global temperature between 2024 and 2028 will be between 1.1 C and 1.9 C above the 1850-1900 baseline each year. And it adds that there is an 86 percent probability one of the coming five years will be the warmest the planet has ever experienced, breaking 2023's record.

The report, titled WMO Global Annual to Decadal Update, said the 80 percent probability that at least one of the next five years will pass the 1.5 C mark had been zero as recently as 2015, highlighting how quickly things have changed.

The European Union's Copernicus Climate Change Service has also uncovered evidence the planet is warming faster than expected and said each of the previous 12 months have set global temperature records.

Carlo Buontempo, director of the Copernicus Climate Change Service, said: "It is shocking but not surprising that we have reached this 12-month streak … We are living in unprecedented times, but we also have unprecedented skill in monitoring the climate and this can help inform our actions."

Under the Paris Agreement, nations vowed to keep the long-term global average temperature well below 2 C above the pre-industrial temperature, and to try to limit it to 1.5 C.