Limiting Overshoot – Navigating Exceedance of 1.5°C and Pathways Towards Return

UNEP’s Limiting Overshoot report examines global warming’s exceedance of 1.5°C, which is now expected across central estimates, and argues that the magnitude and duration of this overshoot are not predetermined. The report finds that every additional fraction of a degree and year above 1.5°C increases exposure to climate hazards and the likelihood of irreversible loss. UNEP stresses that exceeding 1.5°C does not make the Paris goal irrelevant: rapid near-term emissions reductions can still limit peak warming and shorten the overshoot period, while sustained net-negative CO₂ emissions could eventually bring temperatures back down. The authors caution, however, that carbon dioxide removal is not a substitute for stringent emissions reductions, given its uncertain scalability, durability and feasibility at scale. The report calls for mitigation and transformational, systems-based adaptation to advance together throughout the overshoot pathway, alongside strengthened resilience and attention to equity to avoid deepening existing inequities as overshoot unfolds.