Global warming could cross the critical 1.5°C threshold within the next few years, according to a recent report from the United Nations Environment Programme (UNEP). The agency warned that continued warming would increase the risk of extreme weather and place additional pressure on ecosystems, glaciers and low-lying coastal cities.

The 2015 Paris Agreement set a goal of keeping global warming below 1.5°C, but UNEP said the likelihood of exceeding that level is now high. Countries therefore need to limit not only the eventual temperature peak but also how far and how long warming remains above the threshold.

UNEP said returning temperatures to around 1.5°C would still require major cuts in greenhouse gas emissions as well as the removal of carbon dioxide already accumulated in the atmosphere. Every additional 0.1°C of warming and each year of delayed action could increase climate risks, while some environmental damage may remain irreversible even if temperatures later decline.

Under an optimistic scenario in which countries fully meet their existing emissions commitments, warming could peak at around 1.8°C above pre-industrial levels. If current policies continue, the median projection for 2100 is about 2.6°C. UNEP stressed that measures such as reforestation can help slow warming but cannot replace deep reductions in greenhouse gas emissions.