A new United Nations report released on October 21 projects that global warming is likely to surpass earlier estimates, with even the most optimistic scenario indicating average temperatures rising between 1.7°C and 1.8°C above pre-industrial levels by the middle of this century. The findings underscore the urgency for more substantial and immediate cuts in greenhouse gas emissions despite accelerated adoption of renewable energy and implementation of climate policies globally.
The report from the UN Environment Programme (UNEP) outlines ambitious reduction targets that will be necessary to achieve the best-case temperature outcomes. Emissions need to drop by 18% from 2025 levels by 2030, 45% by 2035, and 69% by 2040. However, current national commitments fall significantly short, with planned reductions estimated at only 5% to 8% by 2030 and 11% to 15% by 2035.
Under existing policies, the report forecasts global temperature increases reaching approximately 2.8°C by 2100. Even if all countries fully implement their current climate pledges, warming is expected to reach around 2.6°C by century’s end. These projections have been revised upward compared to assessments made in 2025, influenced in part by the United States' withdrawal from the Paris Agreement and updated evaluations of past emissions data.
As nations prepare for the upcoming COP31 climate conference in Turkey, UN Secretary-General Antonio Guterres emphasized the critical need to maintain efforts to curb emissions that contribute to increasingly severe weather events, including floods and wildfires. He noted that while surpassing the 1.5°C threshold does not signal defeat, it remains imperative to minimize the extent and duration of any temperature overshoot. Guterres highlighted the goal of reducing global temperatures back below 1.5°C by the end of this century.
The 2015 Paris Agreement commits countries to limiting global temperature rises to well below 2°C above pre-industrial levels, with an aspirational aim of 1.5°C. The latest UNEP report acknowledges that keeping warming within 1.5°C without exceeding it is no longer feasible. It identifies a "lowest possible" overshoot scenario that offers about a 50% chance that temperatures could be reduced to 1.5°C or below by 2100. This scenario, however, relies heavily on large-scale carbon dioxide removal technologies, whose practical effectiveness and deployment remain uncertain.
The report further indicates that climate action plans submitted since 2025 have not altered warming projections, underscoring the gap between commitments and the scale of emissions reductions needed to meet global climate targets.