Warming Oceans Could Reshape Marine Life and Threaten Global Food Security

To understand how ocean warming threatens food security, one must look at the microscopic foundations of marine life. Phytoplankton—tiny drifting organisms that form the base of the marine food web—thrive in specific temperature and nutrient bands. As upper ocean layers warm, thermal stratification increases. Warm, light water sits stubbornly on top of cold, nutrient-dense water, cutting off the vertical mixing that brings vital nitrates and phosphates to the surface.