Table of Contents
- 1 Why do glaciers flow faster in the center?
- 2 Why does the top center of a glacier flow faster than the sides or base of a glacier?
- 3 Why do you think this section of the glacier is the thickest deepest?
- 4 Why do Glaciers flow faster at the top than the bottom?
- 5 What is the flow of a valley glacier?
- 6 How does the equilibrium line move down a glacier?
Why do glaciers flow faster in the center?
The glacier begins to move under its own weight. The glacier is so heavy and exerts so much pressure that the firn and snow melt without any increase in temperature. The flowing ice in the middle of the glacier moves faster than the base, which grinds slowly along its rocky bed.
Why does the top center of a glacier flow faster than the sides or base of a glacier?
The central and upper portions of a glacier, as do those portions of a stream, flow more quickly than those near the bottom and sides, where friction between the ice and valley walls slows down the flow. In general, the rate of plastic flow is greater than the rate of basal sliding.
Why do you think this section of the glacier is the thickest deepest?
Continental glaciers do not flow “downhill” because the large areas that they cover are generally flat. In continental glaciers like Antarctica and Greenland, the thickest parts (4,000 m and 3,000 m respectively) are the areas where the rate of snowfall and therefore of ice accumulation are highest.
Do glaciers flow faster with or without meltwater at the base?
temperature: in general, temperate and polythermal glaciers flow at greater velocities than polar glaciers. This is because temperate and polythermal glacial ice is warmer and is therefore able to deform more easily and, further, the presence of meltwater at their base promotes basal sliding.
Why do glaciers flow?
Glaciers move by a combination of (1) deformation of the ice itself and (2) motion at the glacier base. This means a glacier can flow up hills beneath the ice as long as the ice surface is still sloping downward. Because of this, glaciers are able to flow out of bowl-like cirques and overdeepenings in the landscape.
Why do Glaciers flow faster at the top than the bottom?
The central and upper portions of a glacier, as do those portions of a stream, flow more quickly than those near the bottom and sides, where friction between the ice and valley walls slows down the flow. In general, the rate of plastic flow is greater than the rate of basal sliding.
What is the flow of a valley glacier?
A valley glacier has various components of flow. First, the entire glacier moves as a single mass over the underlying rock surface. The pressure from the weight of the glacier generates a layer of water that helps the ice glacier move downslope. This process is called basal sliding.
How does the equilibrium line move down a glacier?
The equilibrium line moves down (1) or up (2) a glacier as the mass balance changes. Ice Flow: Glaciers move by internal deformation (changing due to pressure or stress) and sliding at the base.
How do different parts of a glacier move differently?
Different parts of a glacier move at different speeds. The flowing ice in the middle of the glacier moves faster than the base, which grinds slowly along its rocky bed. The different speeds at which the glacier moves causes tension to build within the brittle, upper part of the ice.