Overview

• May 2025 global mean air temperature averaged 15.79°C, making it the world’s second-warmest May on record
• Ocean surface temperatures reached 20.79°C in May, sustaining record-breaking marine heatwaves across the North Atlantic and Mediterranean
• Greenland’s ice sheet melted at 17 times its average rate between May 15 and May 21, intensifying contributions to sea-level rise
• Spring rainfall in parts of Europe fell to its lowest levels since at least 1979, exacerbating drought conditions and stressing water reserves
• The Arctic continues to warm roughly four times faster than the global average, further destabilizing polar ecosystems