By Fatma Younis
A four-year study warns that warming seas around the UK and the wider north-east Atlantic could destabilise marine food webs, weaken ocean health and jeopardise food security by 2050.
Study Details and Projections
The research, led by the Centre for Environment, Fisheries and Aquaculture Science (Cefas) and published in Science Advances, involved an international team from institutions including the University of East Anglia and the Marine Biological Association. Using long-term datasets and advanced machine-learning techniques, scientists projected climate-driven biodiversity changes under a scenario of 3°C warming by 2100. The seas around the British Isles, particularly the southern North Sea, have been identified as one of 20 global marine climate hotspots that have warmed fastest over 50 years.
Predator-Prey Imbalance
While fish and seabed invertebrate diversity may increase by about 12% by mid-century, key plankton groups lower in the food chain are projected to decline — phytoplankton by roughly 3% and zooplankton by about 7% by 2050. This imbalance could disrupt marine food webs and reduce ecosystem resilience. "What surprised us is that warming doesn't increase or decrease biodiversity across the board," said Elena Couce, a marine ecologist at Cefas and co-lead author. Lily Greig, also a co-lead author at Cefas, added that gains in predator diversity do not necessarily mean the ecosystem as a whole is becoming more resilient.
Implications for Policy
The findings have been submitted to the UK government's review of marine protected areas, which is examining fishery management measures. Researchers say the study provides an early warning system for potential ecosystem change and urge policymakers to account for climate-driven biodiversity shifts before making further management plans.
