EoY's Revision Y8 Flashcards
What is a Cold Environment
An area of land in which is permanently covered with ice. They are full of glaciers and ice sheets with temperatures constanly uder freezing.
Latitude Definition
The further you are away from the equator. This affects how hot are cold a places is (near or far)
Altitude Definition
The higher a point of land is, the colder it will be every 100m up approximately 1°C of heat is lost.
Continentality definition
However far a place is from the sea. The warmer it will be in the summer, but the colder it will be in the winter. If your near the sea, the milder the summers will be and the warmer the winters will get.
Glacial Inputs
Precipitation, Rocks, Snow, Avalanches, Boulders and any other material that may add considerable amounts of weight onto it, even forces, such as gravity
Glacial Processes
The weight of the glacier. This is what helps it to travel through anything in it’s path. A slope and gravity are crucial at this pint, as well as weight.
Glacial Outputs
The main outputs of a glacier at the end are ice, meltwater, sediment and V or U shape valley when it has all melted.
The two zones of a glacier
There are two zones of a Glacier. There is the Accumulation Zone and the Ablation Zone. The Accumulation Zone is the first half of the Glacier where ice, precipitation e.c.t are accumulated. The ablation zone is where all of the outputs are outputted and where the Glacier advances and retreats.
Accumulation>Ablation=Glacier Advances (in winter)
Accumulation
Types of Glacial Erosion
Abrasion
Plucking
Freeze Thaw
Abrasion:
Erodes with a sandpaper affect
Grids sediment across the ground and scrapes larger rocks along
Leaves a smooth shiny rock face behind on the surface
Big Scratches are left on the Valley Floor
Plucking:
Occurs when meltwater freezes in cracks and attaches itself to the rock. Overtime, the rocks are pulled off as the cracks usually end up breaking the piece of rock off. This happens as the glacier is moving.
Freeze Thaw:
When water or rain gets in cracks of bedrock, it will freeze and expand and will make the rocks looser, making it easier to break off.
Occurs down the sides of Glaciers and forms a scree. A scree is when bits and fragments of rock break off the main mountain and onto the glacier.
How are Corries formed?
Snow builds up in a hollow high up on the North Face of a mountain. Sometime later a small glacier will form.
The ice moves under it’s own weight in a circular way called rotational movement.
A small corrie full of ice flows out onto the main valley glacier
The mountain top is weathered by Freeze-Thaw. Persistant freezing and melting breaks sediment off which falls into the ice.
Erosion on the back wall is caused by plucking. Water freezes and pulls off rock. It develops a vertical shaped, jagged appearance.
Rocks that have fallen into the glacier, scrape away the floor with abrasion. A deep bowl shape has been formed.
There is less erosion at the front of the corrie as there is at the back so a lip or rock bar forms. Also moraines are deposited here.
When the ice melts, a small, but very big lake often forms in the hollow called a tarn.
Arêtes and Pyramidal Peaks
Arêtes and Pyramidal Peaks are formed in the following ways:
An Arête is basically a back-to-back Corrie where a ‘knife edged ridge’ is formed. The process is exactly the same as shown in a corrie but they are both just made back-to-back.
Pyramidal Peaks are like Arêtes but there are 3 Corries instead of 2. 3 ‘knife edged ridges’ are formed and a Pyramidal Peak is made at the top.
How are V shaped valleys formed
They are formed by glaciers creating the original valley and then a river eroding it even more to create the V shape.