The impacts of climate change on sea temperature around the UK and Ireland

What is already happening? • Sea surface temperature (SST) around the UK generally shows a significant warming trend of around 0.3C per decade over the last 40 years. • Regional variations exist in this trend with surface warming being greatest across the southern North Sea and least across the north-west of the domain. • Warm-season (Autumn) near-bottom temperatures have increased significantly across the southern North Sea over the last 30 years, but not across other regions of the domain. • Compared to 1982–1998, the annual number of marine heatwaves increased around the British Isles by an average of four events per year in the period 2000–2016. Larger increases of up to six additional events per year occurred to the north of the British Isles. Smaller changes occurred to the south of the region.