Scientists have recently observed major changes in these
glaciers: several have broken up at the ocean end (the
terminus), and many have doubled the speed at which they are retreating.2, 5 This has meant a major increase in the amount of ice and water they discharge into the ocean, contributing to sea - level rise, which threatens low - lying populations.2, 3,5 Accelerated melting also adds freshwater to the oceans, altering ecosystems and changing ocean circulation and regional weather patterns.7 (See Greenland ice sheet hotspot
for more information.)