UN Report Warns Global Warming Will Breach 1.5°C Threshold, Maps Route Back Below Limit

UN Warns Earth Will Breach 1.5°C Warming Goal, Calls For Plan To Bring Temperatures Back Down

The United Nations has acknowledged that the world is on track to cross the 1.5°C global warming threshold agreed under the Paris climate accord, forcing governments to shift their focus from avoiding the limit to containing the damage and eventually reversing the rise in temperatures.

A new report by the UN Environment Programme (UNEP) says continued greenhouse gas emissions from fossil fuels will push global temperatures beyond the 1.5°C mark within the next few years.

The assessment does not suggest abandoning the target. Instead, it calls for an “overshoot” strategy in which global temperatures are first prevented from rising too far above 1.5°C and then gradually brought back below the threshold.

“Humanity is speeding past the limit to avoid climate catastrophe,” UN Secretary-General António Guterres said.

1.5°C Threshold Now Within Reach

The Paris agreement established 1.5°C of warming above pre-industrial levels as a key benchmark because scientists have identified significantly greater risks at higher levels of warming.

The planet is already about 1.4°C warmer than pre-industrial conditions when measured using a long-term average.

The latest UNEP report says the 1.5°C threshold will be crossed “in the next few years”. Under the most ambitious climate scenario, warming could peak at around 1.8°C around the middle of the century before declining.

However, policies currently in place could put the world on a trajectory toward roughly 2.6°C of warming by 2100.

Scientists Urge Action To Limit ‘Overshoot’

The report describes the expected temperature path as a rise above 1.5°C followed by a peak and, eventually, a gradual decline.

UNEP Executive Director Inger Andersen said the 1.5°C target remains the objective, but governments must now prepare to reach it from above. Scientists emphasise that crossing the threshold does not mean climate action becomes pointless. Every fraction of a degree of additional warming avoided can reduce the severity of climate impacts.

Report co-author Joeri Rogelj of Imperial College London warned that every five-year delay in cutting emissions could increase peak warming by at least 0.1°C.

More Extreme Weather, Food And Water Risks

The period in which temperatures remain above 1.5°C could last for decades, bringing greater climate risks even if global temperatures eventually decline. The report warns of increased deaths and illness from extreme weather, reduced food production, worsening water shortages and economic losses. Vulnerable ecosystems, including coral reefs, face growing risks of irreversible damage.

Scientists also warn about potential climate tipping points, including large-scale melting of the Greenland and West Antarctic ice sheets, damage to the Amazon rainforest and disruption of Atlantic Ocean circulation.

Some regions could become increasingly difficult to insure or even uninhabitable as climate risks intensify.

The UN has therefore urged governments to strengthen adaptation measures, particularly to protect poorer communities that are expected to face disproportionate impacts.

Carbon Removal Could Help Reverse Warming

Bringing temperatures back below 1.5°C would require more than cutting future emissions. The world would also need to remove significant amounts of carbon dioxide from the atmosphere. Forestation and restoring ecosystems can help, but the report says these measures alone would have a limited effect on global temperatures.

More advanced carbon-removal technologies could therefore become necessary, although scientists continue to debate their cost, reliability and ability to operate at the scale required. Climate scientist Rob Jackson of Stanford University, who was not involved in the report, said the challenge now involves stopping the rise in emissions and eventually reversing the buildup of greenhouse gases.

The UN’s latest assessment offers a stark message: the world may no longer be able to prevent a temporary breach of the 1.5°C target, but rapid action can still determine how high temperatures rise, how long they remain elevated and whether humanity can eventually return below the danger threshold.