Could be an iceberg, or an ice flow.
The verb form can be an adjective (e.g. drifting ice, drifting debris).
Icebergs (drifting ice) in Antarctica have broken off from the glaciers and ice shelves that stretch out over the sea at the continent's coastline.
Floe
Drifting sea-ice from ~860 A.D.
"leads"
A layer of drifting ice is commonly referred to as an "ice floe." Ice floes are large, flat areas of floating ice that can vary in size and thickness, often found in polar regions or during winter months in colder climates. They can break off from glaciers or ice sheets and drift in the ocean or sea currents.
because of all the ice drifting to town you would not feel it and because we don't have lot's of ice anyway
The icebergs had been drifting further South than usual.
Ice deflectors were added to the base of each pier to break up ice sheets drifting down the Northumberland Strait during the winter. These structures help prevent the ice from accumulating around the piers and causing damage.
drifting
The Norwegian explorer, Fridtjof Nansen proved the Arctic was a deep polar ocean with a drifting ice cap in the late 1890's. Previously there were ideas that within the belt of ice, open shallow water, perhaps land surrounded the North Pole.
Not a glacier, but an iceberg, which was drifting South from the Arctic regions after breaking off from the Polar ice-cap in the warmer Spring weather.