The upper area of a glacier where the rate of accumulation is higher than the rate of ablation. Occurs over a time period when ablation
averaged across the whole glacier exceeds accumulation averaged across the whole glacier
. The glacier becomes smaller and the end of the glacier goes back.
When ablation exceeds accumulation The glacier is quizlet?
The upper part of a glacier, where accumulation exceeds ablation, is called
the accumulation zone
. A type of glacial movement that occurs within the glacier, below a depth of approximately 50 meters, in which the ice is not fractured.
When accumulation is greater than ablation what happens to a glacier?
As long as snow accumulation equals or is greater than melt and ablation, a
glacier will remain in balance or even grow
. Once winter snowfall decreases, or summer melt increases, the glacier will begin to retreat.
What is the difference between the zone of accumulation and the zone of ablation?
Zone of Accumulation: The region where snowfall adds ice to the glacier. … Zone of Ablation: The region where ablation subtracts ice from the glacier through melting or sublimation.
Equilibrium Line
: A boundary between the zone of accumulation and ablation controlled by elevation and latitude.
What occurs in accumulation and ablation zones in a glacier?
On a glacier, the accumulation zone is the area above the firn line, where
snowfall accumulates and exceeds the losses from ablation
, (melting, evaporation, and sublimation). The annual equilibrium line separates the accumulation and ablation zone annually.
What is the relationship between accumulation and ablation?
The relation between accumulation and ablation for a glacier (also called ‘glacier budget’).
It is positive if over a year there is more accumulation than ablation
. It is negative if there is more ablation than accumulation. The lower area of a glacier where the rate of ablation is higher than the rate of accumulation.
Where is the largest existing glacier located?
The world’s largest glacier is the Lambert glacier
in Antarctica
, according to the United States Geological Survey. The glacier is more than 60 miles (96 km) wide at its widest point, about 270 miles (435) long, and has been measured to be 8,200 feet (2,500 meters) deep at its center.
When accumulation exceeds wastage the front of the glacier advances?
When accumulation exceeds wastage, the glacier advances. When wastage exceeds accumulation,
the glacier retreats
. When the two are equal, the terminus of a glacier remains stationary.
Where does a glacier move the fastest?
The ice in the middle of a glacier
flows faster than the ice along the sides of the glacier.
Which is an example of a terminal moraine?
Examples. Terminal moraines are one of the most prominent types of moraines in the Arctic. … Other prominent examples of terminal moraines are the
Tinley Moraine
and the Valparaiso Moraine, perhaps the best examples of terminal moraines in North America. These moraines are most clearly seen southwest of Chicago.
What happens in the ablation zone?
Ablation zone or ablation area refers to the
low-altitude area of a glacier or ice sheet below firn with a net loss in ice mass due
to melting, sublimation, evaporation, ice calving, aeolian processes like blowing snow, avalanche, and any other ablation.
What type of ice is found at the ablation zone?
Ablation zone—the part of the glacier where summer melting exceeds winter accumulation. This includes not only the total melting of the snow cover of the last winter but also a layer
of glacier ice
. A deficit of mass appears in that area. The zone lies at lower altitudes of the glacier surface.
What causes glacial ablation?
As ice flows downhill, it either reaches warmer climates, or it reaches the ocean
. This causes various processes of melt, or ablation, to occur. … The lower part of the glacier generally loses more mass from ablation than it receives from accumulation. This part of the glacier is the ablation zone.
What is accumulation and ablation?
The accumulation area is
situated at the upper part of a glacier where the precipitation is mainly accumulated
, while the ablation area is placed in the lower part where the precipitation is expended (Figure 1). Usually, the upper part of a mountain glacier is actually a firn basin.
Is ablation a form of erosion?
Ablation refers to the
melting of snow or ice
that runs off the glacier, evaporation, sublimation, calving, or erosive removal of snow by wind. Air temperature is typically the dominant control of ablation, with precipitation exercising secondary control.
What is the meaning of accumulation zone?
area of a glacier where more mass is gained than lost
. glaciers.
