World must prepare for 1.5C temperature overshoot, UN warns

The UN has issued a stark assessment that the world must prepare for a scenario in which global temperatures temporarily or permanently exceed the 1.5°C threshold above pre-industrial levels, a benchmark considered critical to limiting severe climate impacts.

While UN Secretary-General Antonio Guterres acknowledged last year that breaching the 1.5°C limit was becoming increasingly probable, this represents the first occasion a major UN agency has released a comprehensive report directly confronting the issue. The report underscores that current national climate commitments and global emissions trajectories make overshooting the target difficult to avoid.

The shift in framing reflects growing recognition within the international community that mitigation efforts, while essential, may not prevent temporary exceedance of the 1.5°C threshold. This has prompted the UN to emphasize the urgent need for robust adaptation measures and climate resilience strategies, particularly in vulnerable regions.

The assessment carries significant implications for developing nations and small island states, which face disproportionate risks from accelerated warming. Experts warn that preparations must intensify regardless of mitigation successes, as some level of temperature overshoot now appears virtually unavoidable under most climate scenarios.

The UN report calls for a comprehensive approach that combines sustained emissions reductions with strengthened adaptation infrastructure, increased financing for climate resilience, and technologies capable of removing carbon from the atmosphere.