A major Greenland glacier is interacting with the ocean tides, resulting in previously unaccounted for melting and potentially faster sea level rise. Its grounding line–where the ice sheet begins to extend out on top of the ocean–can shift significantly as tides come in and out daily, introducing another major source of melting that could be accelerating sea level rise. The phenomenon could worsen in the future as ocean temperatures climb. Sea surface temperatures were at their highest on record this spring, alarming scientists. Greenland’s melting ice is the single largest contributor to sea level rise. But current projections don’t account for this newfound contribution from under-ice interactions with warming tides. Were these dynamics included in models, it would increase projections of sea level rise by up to 200% for all glaciers ending in the ocean (most of northern Greenland and all of Antarctica).
www.cnn.com/2023/05/08/us/greenland-petermann-glacier-melting-climate/index.html