A marine heatwave has been building in the ocean surrounding the UK during an exceptionally warm and dry spring. In other words, the sea surface temperature has been within the top 10% of records for each day of the year since at least the beginning of 2025.
How can we know the temperature of the sea surface over such a large area? Throughout April and May 2025, scientists have been able to map and monitor the seas surrounding the UK via satellites, buoys and other floating devices, plus computer models that simulate the ocean’s physical and chemical properties.
