A summer of record-breaking heat is drying up rivers across Europe as around half of the continent faces an unprecedented drought. In the UK, the driest July in over 80 years has largely evaporated the source of the River Thames. Italy’s longest waterway, the River Po, has sunk to record lows, threatening food production. And in Germany, low water levels in the Rhine are threatening to make boat passage impossible, cutting off a major shipping route. Scientists have warned that climate change means extreme heat and drought will be more common in the future.