Glacier
Glaciers are a system of flowing ice that form where more snow accumulates each year than melts. There are two major types of glaciers, continental and valley glaciers, which produce distinctive erosional and depositional landforms. As ice flows, it erodes the surface of the land by abrasion and plucking. Sediment is transported by the glacier and deposited where the ice melts. In the process, landscape is greatly modified.
Glacial ice
A glacier is a natural body of ice formed by the accumulation, compaction, and recrystallization of snow that thick enough to flow. It is a dynamic system involving the accumulation and transportation of ice. The movement of ice is a critical factor. A mass of ice must move or flow to be considered a glacier. Bodies of ground ice, formed by the freezing of groundwater within perennially frozen ground, are not glaciers, nor is the relatively thin sheet of frozen seawater known as sea ice, which is so abundant in the polar regions.