Asked by Erik
The time taken for glacier ice to thicken sufficiently to start to move downslope will depend on:
- The rate at which snow builds up
- The slope of the ground.
Small, simple glaciers are driven by the gravitational driving force ( τb), as given by the equation:
τb = ρigh sin αS
Where ρigh is the density of the ice (ρi), g is the acceleration due to gravity, and h is the thickness of the ice. This part of the equation is derived from Newton’s Second Law (F = ma), where the mass of the ice is the density times the height and the acceleration is the acceleration due to gravity.
αS is the ice surface slope. Steeper slopes tend to result in faster-flowing glaciers. The gravitational driving stress is resisted by basal and lateral drag against the valley floor and walls.
See more information on how glaciers flow here.