World may breach 1.5C warming threshold in 7 years

The world may cross the crucial 1.5 degrees Celsius global warming threshold in seven years as fossil fuel carbon dioxide emissions continue to rise, scientists warned Tuesday, urging countries at the COP28 talks to "act now" on coal, oil and gas pollution.

Battle lines are being drawn over the future of fossil fuels at the United Nations climate summit in Dubai, with big polluters trying to see off calls for an agreement to phase out the carbon-intensive energy responsible for most of human-caused greenhouse gas.

Fossil fuel CO2 pollution rose 1.1 percent last year, according to an international consortium of climate scientists in their annual Global Carbon Project assessment, with surging emissions in China and India — now the world's first and third biggest emitters.

They estimated that there is a 50 percent chance warming will exceed the Paris deal's goal of 1.5C over multiple years by around 2030, although they noted uncertainties around warming from non-CO2 greenhouse gases.

"The time between now and 1.5 degrees is shrinking massively, so to keep a chance to stay below 1.5C, or very close to 1.5C, we need to act now," the report's lead author, Pierre Friedlingstein of Exeter University's Global Systems Institute, told reporters.

'Wrong direction'

The landmark 2015 Paris Agreement saw countries commit to limiting temperature rise to well below 2C above the preindustrial era and preferably 1.5C. 

The more ambitious 1.5C goal has since taken on greater urgency as evidence emerges that warming beyond this could trigger dangerous and irreversible tipping points.

To keep to that limit, the UN's IPCC climate science panel has said CO2 emissions need to be halved this decade.

That is becoming a more challenging task as emissions continue to rise, the Global Carbon Project found.

Glen Peters, a senior researcher at the CICERO Center for International Climate Research, said CO2 emissions are now six percent higher than when countries signed the Paris deal. 

"Things are going in the wrong direction," he said.

That is despite a promising surge in renewable energy, a key issue at the Dubai climate talks where more than 100 countries have signed a call to triple renewable capacity this decade.

"Solar wind, electric vehicles, batteries, they're all growing rapidly, which is great. But that is only half the story," he said. 

"The other half is reducing fossil fuel emissions. And we're simply not doing enough."