The Mediterranean Sea experienced a record-breaking heatwave in summer 2025. We compared this event to similar patterns from past decades to see how a warmer climate changed its strength. We found that today's warmer background added about 1.5 °C to the sea surface, making the heatwave far more intense and widespread. This shows how climate change is turning ordinary weather patterns into extreme events, with major impacts on marine life, coastal communities, and economies.

This study combines official records, news reports, social media posts, and search data to track urban flood events in twenty major Chinese cities from 2000 to 2024. It builds a comparable database and uses an interpretable machine learning framework to measure flood severity across cities and years. Results show a clear north south contrast: southern river and coastal cities face frequent severe floods, while northern cities usually face lower risk but suffer sudden extremes during rare storms.