1.5°C Warming 'Unavoidable': UN Emissions Gap Report 2026

The United Nations has confirmed that 1.5°C warming is now unavoidable, according to the UN Emissions Gap Report 2026 published on 21 October 2026. Scientists state that no emissions pathway remains to keep the planet below the 1.5°C threshold set out in the Paris Agreement, marking a historic failure in global climate efforts.

What Does the UN Emissions Gap Report Say?

The report, titled Limiting Overshoot, is the first from the UN Environment Programme to call crossing 1.5°C imminent and unavoidable. Even the most optimistic scenario peaks at 1.7–1.8°C around mid-century before temperatures return below 1.5°C by 2100. Without stronger action, current policies put the world on track for about 2.8°C of warming, while fully delivering existing national climate plans would still only limit warming to 2.6°C.

The Paris Agreement 1.5°C target has guided climate policy for more than a decade, but the report says political will and concrete plans have fallen short.

Why Did the World Miss the 1.5°C Target?

Emissions kept rising

Rather than falling, greenhouse gas emissions continued to climb. Michel den Elzen, a researcher at the Netherlands Environmental Assessment Agency and Vrije Universiteit who contributed to the report, said: Emissions have continued to rise and we have lost a number of years again. The world needed to burn less coal, oil and gas; instead it burned more.

US withdrawal and weak national plans

The US withdrawal from Paris Agreement under President Trump eliminated nearly all federal climate policy, while new plans from other countries delivered only marginal emissions reductions. UNEP chief Inger Andersen warned that overshoot is not surrender, but each additional fraction of a degree worsens floods, heatwaves and wildfires.

Can We Still Limit the Overshoot?

Yes, but only with dramatic, immediate action. The lowest-overshoot pathway requires cutting emissions by 18% by 2030, 45% by 2035 and 69% by 2040 compared with 2025 levels. It also requires tripling renewable energy capacity by 2035, phasing out coal by 2040 and scaling up carbon removal. Den Elzen said: It is now or never.

Even if all emissions stopped today, existing greenhouse gases would still need to be removed from the atmosphere through technologies such as CO2 storage and large-scale reforestation.

What Are the Impacts of Crossing 1.5°C?

Above 1.5°C, coral reefs would nearly disappear, sea-level rise would accelerate and extreme heat would become more dangerous. Scientists estimate each additional 0.1°C costs about 1.2% of global GDP. The report warns of irreversible climate tipping points such as Amazon dieback, ice-sheet collapse and disruption of Atlantic currents.

The 1.5°C limit was first championed by Pacific island nations at the 2009 Copenhagen summit because sea-level rise threatens their very existence.

FAQ

Is 1.5°C warming really unavoidable?

Yes, according to the UN Emissions Gap Report 2026, no scenario keeps global warming below 1.5°C. The goal now is to make the overshoot as brief and limited as possible.

What happens if we exceed 1.5°C?

Impacts intensify with every fraction of a degree: more extreme weather, ecosystem loss, food and water insecurity, and rising risk of irreversible tipping points.

Can we return below 1.5°C after overshooting?

Technically yes, but it requires massive carbon dioxide removal, reforestation and deep emission cuts. The lowest-overshoot scenario returns below 1.5°C by 2100.

What is COP31?

COP31 is the UN climate summit taking place in Antalya, Türkiye, in November 2026, where countries will discuss the report and the second Global Stocktake.

How much do emissions need to fall?

Emissions must drop 18% by 2030, 45% by 2035 and 69% by 2040 versus 2025 levels to follow the lowest-overshoot pathway.