Describe the processes by which glaciers move. (6 marks).
Glacier movement depends on whether it is warm or cold. This depends on the pressure melting point (PMP), which is when ice is on the verge of melting. An increase in pressure can increase melting and therefore movement due to lubrication.
Accumulation is the inputs of the glacier system by precipitation as snow, avalanches, debris as rocks and melt water. Ablation is the outputs of the glacier system which include melt water, till-rock deposition, calving iceberg, evaporation and wind erosion.
If there is more accumulation than ablation then the glacier advances due to gravity. If there is less accumulation than ablation there is more melt water, which acts as a lubricant, the glacier then moves down the valley but retreats due to climate, altitude and latitude.
There are two types of glaciers, cold polar and temperate. Cold glaciers are in very cold areas where there is minimal melting, only 1-2 cm a day due to little friction because it is frozen to the bed and is on gentle slopes.
Glacier movement depends on whether it is warm or cold. This depends on the pressure melting point (PMP), which is when ice is on the verge of melting. An increase in pressure can increase melting and therefore movement due to lubrication.
Accumulation is the inputs of the glacier system by precipitation as snow, avalanches, debris as rocks and melt water. Ablation is the outputs of the glacier system which include melt water, till-rock deposition, calving iceberg, evaporation and wind erosion.
If there is more accumulation than ablation then the glacier advances due to gravity. If there is less accumulation than ablation there is more melt water, which acts as a lubricant, the glacier then moves down the valley but retreats due to climate, altitude and latitude.
There are two types of glaciers, cold polar and temperate. Cold glaciers are in very cold areas where there is minimal melting, only 1-2 cm a day due to little friction because it is frozen to the bed and is on gentle slopes.