Climate overshoot: the world heading for an irreversible breach of the 1.5 °C threshold

The world is heading towards an “irreversible overshoot” of global temperature thresholds, that is, a breach of the 1.5 °C limit from which it will be hard to return. This is the view of the Climate Action Tracker (CAT), a climate policy analysis group, in its global update released during the COP31 climate summit.¹²³ Under today’s policies, the CAT says average warming would reach 2.7 °C above pre-industrial levels by 2100. A year ago, the estimate was 2.6 °C.¹³

What ‘overshoot’ means

Overshoot means exceeding a temperature threshold, in this case 1.5 °C, and then trying to bring warming back below that level. For the CAT, this is now the “new reality”: the task is to limit the scale and duration of the overshoot.³ The guiding principle set out in the report is to bring warming back below 1.5 °C, and ideally well below it, by 2100, with temperatures continuing to fall after that date. According to the analysis, the 1.5 °C limit will be exceeded in the long term around 2030.³

The CAT’s end-of-century estimates

If governments met their targets for 2030 and 2035, warming would still reach 2.6 °C by 2100, unchanged from last year. Adding long-term targets as well would bring it down to 2.1 °C, compared with the previous estimate of 2.2 °C.³ The CAT’s optimistic scenario, which includes all commitments, long-term targets and net-zero emissions pledges, would lead to 1.9 °C.³

Why the report speaks of stalling

The CAT notes that collective government action has stalled for five consecutive years. The report points to positive signs: in 2025 clean electricity covered all new global demand, India and China are installing renewables at record pace, electric car sales hit new highs, and deforestation in the Brazilian Amazon has fallen significantly.³ According to the report, however, these advances are not enough to bend the emissions curve fast enough. Growing energy demand and the construction of new fossil fuel infrastructure mean that emissions continue to rise.³ The lead author, Sarah Heck of Climate Analytics, says several governments are slowing down and that the United States, Canada and New Zealand are backtracking to an “impressive” degree.³ The European Union has also come under fire: scientists have criticised it for a retreat on climate action.² Niklas Höhne of the NewClimate Institute, by contrast, believes global emissions could be close to peaking and falling faster than expected. He also cites the closure of the Strait of Hormuz, which showed how exposed the world is to geopolitical shocks.³

How much emissions must fall

To keep the overshoot at the lowest level still achievable, the CAT calculates that emissions must fall by about 4% a year until 2030 (range 3-5%). Then by about 7% a year in the first half of the 2030s (6-9%), and by 9% a year between 2035 and 2050 (6-15%).³ The report adds that every year of delay makes the curve steeper.³

This article was written by artificial intelligence from the sources cited, without human review. Automatic newsroom by Redazia.

Sources

Footnotes

1. World heading for ‘irrevocable overshoot’ of global temperature thresholds, analysis warns, Latest news, sport and opinion from the Guardian, 2026-11-12 ↩ ↩²

2. Scientists slam EU for climate action backsliding, euractiv.com, 2026-11-12 ↩ ↩²

3. Press release: Without rapid climate action, the world is heading to “irrecoverable overshoot” | Climate Action Tracker, climateactiontracker.org ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹²