ice stream

An ice stream is a current of ice within an ice sheet that moves significantly faster than the surrounding ice, often flowing towards the sea. These streams are crucial for transporting ice from the interior of large ice masses like the Antarctic and Greenland ice sheets.1

Ice formation in rivers is complex due to water velocity and turbulence. Rivers cool uniformly, and the water can become supercooled below its freezing point. When ice particles, known as frazil ice, form, they are typically small disks. These particles can aggregate, forming slush-like masses on the surface or adhering to the riverbed as anchor ice. Frazil ice is the initial stage of ice formation in rivers and can cause blockages at water intakes.2

Ice streams, such as the Whillans Ice Stream in Antarctica, can exhibit dynamic behaviors like stick-slip motion, driven by tides, and are influenced by subglacial lakes. The flow rate of ice streams is much higher than in the interior of ice sheets, with some reaching up to a kilometer per year.31