UN Sees Higher Global Warming,
Even In Best-Case Scenario 

Society of Environmental Journalists

(October 21, 2026) — “Best-case scenario sees peak of 1.7-1.8 C by mid-century. Need cuts of 18% by 2030, 45% by 2035 from 2025 level.”

“LONDON – Global ​warming is now projected to exceed previous estimates, with even the most ‌optimistic scenario seeing average temperatures rise to 1.7-1.8 degrees Celsius above pre-industrial levels by mid-century, a UN report showed on Wednesday.

Despite a rapid expansion of renewable energy and climate policies that are reducing ​emissions in many countries, the report said “urgent and stringent” cuts were still needed ​to achieve that best-case outcome.

The UN Environment Programme’s report said greenhouse ⁠gas emissions would need to fall 18% from 2025 levels by 2030, 45% by ​2035 and 69% by 2040. Current national plans would cut emissions by only 5-8% by ​2030 and 11-15% by 2035.

The report projected global warming of 2.8 Celsius by 2100 under current policies, or 2.6 C if countries fully implement existing climate pledges. Both estimates are higher than last ​year’s projections, reflecting the US withdrawal from the Paris Agreement and revised assessments of ​historical emissions.

As countries prepare for the next round of climate talks in Turkey, COP31, UN Secretary-General António ‌Guterres ⁠said it was crucial not to give up on efforts to rein in the emissions that are fuelling floods, fires and other natural disasters.”

Source: Simon Jessop reports for Reuters October 21, 2026.