UN report warns of imminent 1.5 C threshold breach

Global temperature rise is set to cross 1.5 C above preindustrial levels, likely within the next few years, pushing climate risks and impacts to increasingly dangerous heights, according to a report released Wednesday by the United Nations Environment Programme.

The sobering projection stands in direct tension with the very target that parties to the 1992 UN Framework Convention on Climate Change enshrined in the convention's landmark 2015 Paris Agreement.

The overarching goal of the treaty is to hold the increase in the global average temperature to well below 2 C above preindustrial levels and pursue efforts to limit the increase to 1.5 C.

Even under the most optimistic scenario, the UNEP report said temperature rise would peak at 1.8 C above preindustrial levels, warning a series of risks.

"Risks and impacts above 1.5 C intensify with every fraction of a degree. They can either grow with time or emerge suddenly," the report warned.

The world, for example, will suffer intensified extreme weather and ecosystem loss, and Small Island Developing States and low-lying coastal cities will face the threat of submersion, it said.

For warming up to or less than 3 C, glaciers could lose more than a quarter of their mass by 2100, raising sea levels by 12.5 centimeters, the report continued.

Considering the scale of the risks and the co-benefits of climate interventions such as a rapid transition away from fossil fuels to renewable energy, the report urged accelerated, collective and global action to get on an overshoot, peak and decline pathway.

How quickly and strongly this action happens will define the shape and trajectory of the pathway, it said.

"Every fraction of a degree matters, and every year spent in overshoot increases climate risks and the potential for irreversible losses," stressed Murat Kurum, president-designate of the 31st session of the Conference of the Parties to the UNFCCC (COP31), which is scheduled to be held in Turkiye, in November.

Kurum, also Turkiye's minister of environment, urbanization and climate change, also said, however, the Overshoot Report makes clear that exceeding 1.5 C should not be seen as a new destination, but as a pathway the world must urgently work to minimize and reverse.

This requires rapid and sustained emissions reductions, alongside ambitious adaptation to protect people, communities and ecosystems, he continued.

"COP31 must turn this urgency into concrete action," he emphasized.

The world needs to accelerate global electrification, reduce methane emissions from waste, strengthen the climate resilience of cities, and enhance the resilience of marine and coastal ecosystems, he said.

"At the same time, mitigation and adaptation should advance together. The choices we make today will determine how high temperatures peak, how long they remain there, and how safely we can return to 1.5 C," the minister added.