Formation, Movement, and Mass Balance
Snow accumulates, compacts, and recrystallizes to form ice.


When it is ~60 m thick, it can flow under its own weight.

Alpine glaciers flow downhill until they melt or meet the ocean.

Continental glaciers  flow outward from where they are thickest (usually areas of highest snow accumulations) and continue until they cross into warmer climates or meet the ocean.

A large amount of rock is frozen into the glacial ice and is carried great distances.







 
Glaciation: snow accumulates in the zone of accumulation and is converted to ice. It flows down to the zone of wastage (or ablation). The boundary between these zones is the equilibrium line. Continental glaciers also have these zones.
Mass balance = difference between the amount of accumulation and the amount of wastage.
A positive mass balance means the glacier will advance (accumulation > wastage).
A negative mass balance means the glacier will retreat (accumulation < wastage).
In both cases, the ice is always moving forward (downhill) due to gravity).
Alpine glaciation is sensitive to climate change – the study of glaciers is important to our understanding of the causes and effects of past and future climate change.