Tidally controlled stick-slip discharge of a West Antarctic ice.

Bindschadler, Robert A; King, Matt A; Alley, Richard B; Anandakrishnan, Sridhar; Padman, Laurence · Science · 2003

basic_science · Level V

Where this comes from

Abstract

A major West Antarctic ice stream discharges by sudden and brief periods of very rapid motion paced by oceanic tidal oscillations of about 1 meter. Acceleration to speeds greater than 1 meter per hour and deceleration back to a stationary state occur in minutes or less. Slip propagates at approximately 88 meters per second, suggestive of a shear wave traveling within the subglacial till. A model of an episodically slipping friction-locked fault reproduces the observed quasi-periodic event timing, demonstrating an ice stream's ability to change speed rapidly and its extreme sensitivity to subglacial conditions and variations in sea level.