Satellite radar interferometry reveals that the speed oi the Ryder Glacier increased roughly threefold and then returned to normal (100 to 500 meters/year) over a 7-week period near the end of the 1995 melt season. The accelerated flow represents a substantial, through short-lived, change in ice discharge. During the period of rapid motion, meltwater-filled supraglacial lakes may have drained, which could have increased basal water pressure and caused the mini-surge. There are too few velocity measurements on other large outlet glaciers to determine whether this type of event is a widespread phenomenon in Greenland, but because most other outlet glaciers are at lower latitudes, they should experience more extensive melting, making them more susceptible to meltwater-induced surges.