Glacial Flashcards
What is a cold environment?
Areas of land permantly covered in ice. They are covered by glaciers, ice sheets and have frozen soil/rock. The temperature is constantly below freezing
Name 4 cold environments:
Africa- Glacier of mount Kilamanjaro
The edge of the India/ Pakistan border -The Himalayas
Ecuador- Catopaxi Glacier, Catopaxi volcan
East Antarctica- Lambert glacier, Mount Sidley
If a location is at a higher altitude how does this affect the temperature?
The location has a colder temperature
How much does temperature decrease by for every 100 metres in altitude?
Temperature usually decreases by 1°C for every 100 metres in altitude.
What is altitude?
Height above sea level
Why does it get colder when a location is a higher altitude?
Air is heated up in our atmosphere when sunlight heats up the land. The land then heats the air above it. The further you are away from land, the less warming it receives. At higher altitudes the air is under less pressure which means heat is less well maintained.
What is a good example of altitude?
Catopaxi glacier with an altitude of 5897m in height
What is continentality?
Distance from the ocean or sea
What is the lowest temperature ever recorded outside Antarctica? What country was it? And how far is it from the nearest ocean?
The lowest temperature ever recorded outside of Antarctica is -71.20C ! This record was set in Siberia, Russia. It is over 4000km from the nearest ocean.
Why is it colder in the middle of continents than to the rest of the countries that are closer to the oceans?
The world’s oceans and sea (because they are so deep and constantly moving) takes a long time to warm up in comparison to land which warms quickly. BUT, once the sea has warmed up, it keeps it heat for much longer (far longer than land) and warms up coastal places. This means that places in the middle of continents in winter, will not receive the warming effect of the sea and will be colder, but warmer in summer.
What is latitude?
Distance from the equator
Why is it cooler near the poles?
Temperatures drop the further an area is from the equator due to the curvature of the earth. In areas closer to the North and South pole, sunlight has to pass through a greater distance of atmosphere to reach the earth. At the earth’s surface the rays are spread out over a larger area than at the equator. As a result, more energy is lost and temperatures are cooler near the poles.
In addition, the presence of ice and snow nearer the poles causes a higher albedo, meaning that more solar energy is reflected, also contributing to the cold.
Why do temperatures drop the further an area is from the equator?
Temperatures drop the further an area is from the equator due to the curvature of the earth.
Facts about latitude lines
Tropic of Cancer 23.5 degrees north
Tropic of Capricorn is 23.5 degrees south
Arctic circle is 66.5 degrees north
What is a glacier?
A glacier is a huge mass of ice that moves slowly over land. It forms when there is a build up of snow over a number of years. They can be found at altitude or sea level. They are known as rivers of ice.
What is the input of the glacier system?
The main input is snow. Over time, the weight of the snow compacts it from powdery into glacial ice. Avalanches from surrounding mountain sides can also provide inputs to the glacial system.
What is the process in the glacier system?
The weight of the compacted ice then combines with gravity to make the glacier move slowly downhill. As it does so, it moves sediment that has dropped onto it - and also erodes its valley (processes in the system).
What is the output in the glacier system?
The main outputs from the system include ice and meltwater - together with lots of sediment.
What two zones is a glacier divided into?
The accumulation zone
The ablation zone
What is the accumulation zone?
The accumulation zone is where there are inputs into the glacial budget.
What is the ablation zone?
The ablation zone is where there are outputs from the glacial budget.
What does ablation cause glaciers to do?
Ablation causes glaciers to retreat in the summer
What does accumulation cause glaciers to do?
Accumulation causes glaciers to advance in the winter
Why does the glacial budget vary?
The glacial budget varies during the course of a year. In the summer, ablation will be at its highest, because of rapid melting of ice. During the winter, higher amounts of snowfall and limited melting will result in accumulation being greater than ablation.
What is plucking?
Plucking is when melt water from a glacier freezes to the base rock and lumps of cracked and broken rock. When the ice advances downhill, rock is plucked from the back wall.
What is the name of the scratches that can occur in the valley floor?
Striations
What is abrasion?
Rock fragments in the ice grind against the rock over which the ice is moving and wears away the land. (Like rough sandpaper) after it scratches the valley floor it leaves smooth, shiny rocks.
What is the Glacial process- freeze thaw weathering?
This is a type of weathering. When the temperature is above 0 degrees the water starts melting and settles into cracks in the rock and then at night the water freezes and expands by 9%. This puts pressure on the surrounding rock. As it thaws, the pressure is released. As this repeats, rocks break away and comes out of the ground where it is plucked by the glacier.
Formation of a corrie:
See book and you will test me on it
What do valley glaciers carve?
U-shaped valleys
What valley is carved by rivers?
V-shaped valley
What is a river valley?
A valley created by rivers
Features of a glaciated valley:
Features of a glaciated valley: very wide and relatively straight, gently curved sides, ‘U’ shaped,
small stream, grassed surfaces, glacial ‘trough’
River valley:
A valley that has been shaped by a river is narrow, steep, V-shaped, has interlocking spurs of hard land and rock scree.
U shaped valley formation:
Look at book
What is the first two digit number called on a grid reference
The first two digit number is called the easting, (they show you how far E/W
you are) this is the number along the top or bottom of the map.
What is the second two digit number called?
The second two digit number is called the northing (how far N/S you are). This is the number at
the side of the map.
What is a ribbon lake on an OS map?
See book
What is a hanging valley on an OS map?
See book
What is a glacial trough on an OS map?
See book
What is a corrie on an OS map?
See book
What happens when glacial valleys continue to erode down?
Sometimes, when glacial valleys continue to erode down, they erode and create a ribbon lake.
What is a hanging valley?
A smaller valley which is located high above the main U-shaped valley.
What is mis-fit stream?
A small river occupying the floor of a u-shaped valley.
What is scree?
A build-up of broken rock fragments at the bottom of a mountain.
What is a truncated spur?
a truncated spur, the ridge has been cut off sharply by the ice (glacier) that flowed down the main valley.
How to find characteristics of a U-shaped valley on a OS map:
https://www.youtube.com/watch?v=SPyTz9CjvbU
Which is going to cause sea levels to rise the most? Melting glacier ice or melting sea ice
Melting glacier ice because as glaciers melt they are added to the sea levels.
Sea ice also melts in warm temperatures but do not cause sea level to rise.
Sea ice is already in the water!
As a result, sea level does not rise when sea ice melts.
Melting glacier ice adds to sea levels because as it melts it adds volume to the glacier.
How would ice melt affect different people globally? About himalayas
SEE BOOK. MEMORISE the paragraph because it will come up in the test as a high mark.
What are the consequences of sea level rise for people?
- global displacement of people
-flooding of major financial hubs such as London- will have a massive impact on the economy
-shotage of food because millions of acres of land will be gone which will lead to hunger and starvation - loss of entire ecosystems which could lead to some animals and plants being extict
- outbreaks of diseases such as cholera
What causes sea levels to rise?
Seawater warms, its volume increases because of thermal expansion which is when water increases in volume because of ice melting. Melting mountain glaciers and in land ice contribute another third of current sea level increases
What is firn?
Half ice
The percentage of the fresh water on Earth is ice?
Ice = 69%
The percentage of the fresh water on Earth is groundwater?
30%
The percentage of the fresh water on Earth is river?
Less than 1%
What is the formation of a pyramidal peak?
See in book
What is the formation of an arete?
See in book
What is a tarn?
A lake in a corrie
How is a u shaped valley formed?
Before glaciation the river carves out a v shaped valley because it erodes out the base. During glaciation the ice fills the whole valley. Rates of erosion increase and it wears away all the sides of the valley. Valley walls and floors are eroded wider and deeper. When the glacier melts a river flows again it did not cause the erosion and is called a misfit stream.
Easier way of remebering: A valley glacier eroding through interlocking spurs created by a river. The glacier erodes the interlocking spurs truncating them forming a U shaped valley.
How does a misfit stream occur?
When the glacier melts a river flows again it did not cause the erosion and is called a misfit stream
