When they begin to accelerate into the sea like they are, well yes. Glaciers are disappearing up valley world wide, the others in artic/antartic circles, are accelerating into the sea and big bigger chunks breaking off with regularity. Glacier Park in the US offers classics examples of Glacier retreat and ultimate extinction. Sea rise is inevitable and add to that thermal expansion of the ocean waters. The two glaciers I walked on in NZ 10 years ago are going there retreat up the valley.
