Now or never: IPCC report warns on critical temperature limit, emissions must decline by 2025

In short, the IPCC says, the world is at a crossroads on whether we should seize the opportunity to avoid climate catastrophe.

It’s now or never.

The fight to keep global heating under 1.5 degrees Celsius has reached “now or never” territory, according to a new report released Monday by the world’s leading climate scientists.

Greenhouse gas emissions must peak by 2025, and can be nearly halved this decade, according to the Intergovernmental Panel on Climate Change (IPCC), to give the world a chance of limiting future heating to 1.5C above pre-industrial levels.

At the same time, methane, a potent greenhouse gas, would also need to be reduced by roughly one-third.

The report found that limiting Earth’s average temperature rise to the ambitious 1.5C (2.7F) agreed by nations under the Paris Agreement, will require “immediate and deep” emissions cuts across every sector of society.

In short, the IPCC says, the world is at a crossroads on whether we should seize the opportunity to avoid climate catastrophe.

“The decisions we make now can secure a liveable future. We have the tools and know-how required to limit warming,” said IPCC Chair Hoesung Lee.

“It’s now or never, if we want to limit global warming to 1.5°C,” IPCC Working Group III co-chair Jim Skea said in a statement accompanying the report. “Without immediate and deep emissions reductions across all sectors, it will be impossible.”

The report on Monday was the third and final section of the IPCC’s latest comprehensive review of climate science, drawing on the work of thousands of scientists. IPCC reports take about seven years to compile, making this potentially the last warning before the world is set irrevocably on a path to climate breakdown.

Though the report found it was now “almost inevitable” that temperatures would rise above 1.5C – the level above which many of the effects of climate breakdown will become irreversible – the IPCC said it could be possible to bring them back down below the critical level by the end of this century. But doing so could require technologies to remove carbon dioxide from the atmosphere, which campaigners warned were unproven and could not be a substitute for deep emissions cuts now.