UN climate report finds breach of 1.5C threshold is now unavoidable

A new United Nations assessment has concluded that the world can no longer prevent global average temperatures from surpassing the critical threshold of 1.5 degrees Celsius above pre-industrial levels.

According to the Emissions Gap Report 2026, published by the United Nations Environment Programme, decades of inadequate mitigation mean that a substantial temperature overshoot is now inevitable. However, the report highlights that aggressive, immediate reductions in greenhouse gas emissions could limit the peak temperature to between 1.7C and 1.8C around the middle of the century and potentially return warming to 1.5C by 2100.

To maintain the lowest possible overshoot path, worldwide emissions must drop by 18 percent by 2030, 45 percent by 2035, and 69 percent by 2040, using 2025 as a baseline. Existing national climate pledges fall far short of these benchmarks, projecting cuts of merely 5 to 8 percent by 2030 and 11 to 15 percent by 2035. Without substantial policy changes, the UN warned that global warming could hit 2.8C by the end of the century.

The report notes that every fraction of a degree beyond 1.5C heightens the risk of irreversible ecological collapse, including the melting of ice sheets, damage to coral reefs, and severe disruption to ocean currents. Sustained high emissions also carry heavy human tolls, with every five years of pollution at present rates adding roughly 0.1C to peak warming.

In 2025, worldwide greenhouse gas output reached roughly 58.4 billion tonnes of carbon dioxide equivalent, showing negligible change from the previous year. While fossil fuel combustion, fluorinated gases, and nitrous oxide emissions continued their upward trend, reductions in wildfire activity provided a partial offset.

Progress remains severely uneven across major economies. Only six G20 members—China, India, Indonesia, Russia, South Africa, and Turkiye—are on track to reach their unconditional 2030 goals under current policies, though India's absolute emissions are still expected to expand. The report also pointed out that the apparent narrowing between government pledges and projected emissions was largely driven by the removal of the United States' targets from global tallies following its exit from the Paris Agreement, rather than real collective policy acceleration.

Reversing warming back down to 1.5C by century's end would depend on extracting roughly 320 billion tonnes of carbon dioxide from the atmosphere and permanently sequestering it. UN researchers cautioned that deploying carbon removal technology at such an immense scale poses major technical and financial hurdles.

Alongside carbon removal, energy systems require a swift transformation. Coal-powered electricity must drop by at least 75 percent by 2035 and be largely eliminated by 2040, while clean electricity capacity needs to triple within a decade. While wind and solar deployment has consistently outpaced earlier forecasts, the continued consumption of fossil fuels and persistent deforestation continue to undermine international climate objectives.