EQ1- How Has Climate Change Influenced The Formation Of Glaciated Landscapes Over Time

Question 1

Approximately how old is the earth

Answer 1

4.6 billion years old

Question 2

What are the two dominant states of the earth which fluctuate

Answer 2

Icehouse state - there is ice and snow on earth

Greenhouse state - there is no ice/snow on earth

Question 3

What state and period is the earth in currently

Answer 3

The earth is in an icehouse state as there is ice on earth

We are currently in an interglacial period

Question 4

What is the Quaternary

Answer 4

The most recent ice age that we are currently in.

It is one of 5 glacial periods in the cenzoic era

Question 5

What are the two epochs in the Quaternary age

Answer 5

The Pleistocene- lasted until 10,000 years ago

The Holocene - Began 10,000 years ago till present day

Question 6

What is the Pleistocene

Answer 6

An epoch in The Quaternary ice age

Is known as an ice age as it has had over 50 glacial- interglacial periods

Question 7

What are the 3 characteristics of the Pleistocene epoch

Answer 7

It was not just a single ice age, there was a number of ice advances and retreats
The extent to each ice advance during each glacial was different
There are many fluctuations

Question 8

What are stadials

Answer 8

Short lived pulses of ice advance

Question 9

What are interstadials

Answer 9

The warmer periods of retreat

Question 10

What is Devensian

Answer 10

Was the last known glacial maximum , which occurred 18000 years ago

Question 11

What is Loch Lomand Stadial

Answer 11

Marked the end of the Pleistocene epoch, 12,000 years ago

Question 12

Explain the long term factors that lead to climate change (milankovitch cycle)

Answer 12

Individually, the orbital variations of precession, eccentricity and obliquity have little impact on the earths weather, but over a 100,000 year cycle these oscillations combine to cause major temperature changes leading to dramatic variations in global ice volumes

Question 13

What is the Milankovitch cycle

Answer 13

A cyclical movement related to the earths orbit around the sun.

There are three of them : precession, eccentricity and obliquity

Question 14

Define positive feedback

How did it lead to climate change

Answer 14

Positive feedback is amplification

To explain the large temperature changes for expanses of ice to form or melt positive feedback is involved.
This happens when a small increase of snow/ice increases the surface albedo, more energy is reflected back into space, leading to further snowfall.
This continues to amplify bringing drastic temperature change

Question 15

Define negative feedback

Answer 15

Trying to restore dynamic equilibrium

Question 16

Explain the short term causes of climate change (volcanic eruption)

Answer 16

Volcanic eruptions emit ash and more importantly sulfur dioxide gas in large quantities
Sulphate aerosols are formed and they stay in the atmosphere for years
They cause an increase in the reflection of radiation from the sun back into space , cooling the earths atmosphere

Question 17

Explain the short term causes of climate change (solar output variations)

Answer 17

Sunspots are dark patches on the face of the sun caused by intense magnetic activity in the interior
An increase in sunspots means that the sun is more active and gives off more energy, heating the earths atmosphere

Question 18

Explain the short term causes of climate change (feedback mechanisms)

Answer 18

Neither solar output variations or volcanic activity can cause climate change
Feedback mechanisms are needed to amplify change associated with short term stadial and interstadial fluctuations

Question 19

Describe the cause of the Loch Lomand Stadial (pleistocene)

Answer 19

One possibility was that it was triggered by the drainage basin of the lake agassiz which disrupted the thermal haline current, cutting off the transfer of heat from the gulf stream ocean current

Question 20

Describe the characteristics of the Loch Lomand Stadial

Answer 20

Ice began to readvance as temperatures lowered by 6-7 degrees

Question 21

Describe the cause of the little ice age (holocene)

Answer 21

A possibility is that four big volcanic eruptions led to global cooling due to the huge amount of sulphate aerosols in the atmosphere
Another possibility was solar output variations

Question 22

Describe the characteristics of the little ice age

Answer 22

Brought cold winters, frozen rivers and lakes
Sea ice extended in Iceland
Artic sea ice spread down south

Question 23

Define the Cryosphere

Answer 23

Places on earth where water is permanently frozen there and stored as snow or ice

Question 24

What are the three main roles of the cryosphere

Answer 24

Constantly exchange mass and energy with other components

Help regulate temperatures on earth

Sensitive barometers of climate change

Question 25

Explain one approach to classifying ice masses (warm based glaciers)

Answer 25

Seen in high altitude locations like the Alps and Subarctic areas
Warmer due to the friction from the glacier moving and geothermal energy from the ground
At the base of the glacier it has reached pressure melting point
Cause glacial meltwater to form which acts as a lubricant
Glacial meltwater causes erosion as the glacier moves
It picks up debris and causes further erosion of the land

Question 26

Explain one approach to classifying ice masses (cold based)

Answer 26

Seen in high altitude locations like the Antarctic and Greenland
Average temperature is below 0 degrees and the ground does not generate geothermal energy
Means no melting of the base or glacial meltwater
Glacier is frozen in place meaning there is an absence of erosion

Question 27

Explain one approach to classifying ice masses (hybrid polythermal glaciers)

Answer 27

Glacier can become so big that its a hybrid polythermal glacier
Cold based in the upper regions and warm based when it extends into warmer climate zones

Question 28

Scale and location - Ice sheet

Give a description, size, degree of constraint and example

Answer 28

A mass of snow/ice with considerable thickeness
50,000 sq/km
Unconstraint
The edge of the east Antarctic

Question 29

What does constraint mean

What does unconstraint mean

Answer 29

Where the ice mass shapes the landscape

Where the ice mass runs over the landscape

Question 30

Scale and location - Ice cap

Give a description, size, degree of constraint and example

Answer 30

Dome shaped mass of glacier ice , found in highland areas
50,000 sq/km
Unconstraint
Northern antarctic peninsula

Question 31

Scale and location - ice field

Give a description, size, degree of constraint and example

Answer 31

Small and determined by the shape of the surrounding land
Less than 50,000 sq/km
Constraint

Question 32

Scale and location - Valley glacier

Give a description, size, degree of constraint and example

Answer 32

A glacier bounded by the walls of a valley and descending mountains
Constraint
In the Alps

Question 33

Scale and Location - Piedmont Glacier

Give a description, size, degree of constraint and example

Answer 33

A glacier which spreads out as a wide lobe as it leaves the narrow mountain valley
Constraint
Southern Axel Heiberg Island

Question 34

Scale and location - Cirque Glacier

Give a description, size, degree of constraint and example

Answer 34

A glacier occupying a cirque ( a hollow formed from glacial erosion)
Small in size
Constraint
Teton Glacier in USA

Question 35

Scale and location - Ice Shelf

Give a description, size, degree of constraint and example

Answer 35

A large slab of ice floating on the sea but remaining attached to land derived ice
Big in size
Unconstraint
Tubular ice bergs in East Antartica

Question 36

What are the 4 parts of the distribution of cold environments

Answer 36

Polar(high latitude) regions : areas of permanent ice

Periglacial (tundra) regions : layer of permanently frozen ground (permafrost)

Alpine/mountain (high altitude) regions : where glaciers are found

Glacial environments : found at edges of ice sheets in mountainous regions

Question 37

What are the different types of evidence for the Pleistocene ice sheet which covered the majority of the UK

Answer 37

Depositional evidence : drumlins and moraines formed

Erosional evidence : includes corries , arêtes and glacial troughs found in Snowdonia and the Lake district

Meltwater evidence: Meltwater channels, glacial tills and eskers were formed

Question 38

Describe the distribution of :

i. High latitude polar ice sheets
ii. High altitude alpine glaciers

Answer 38

Mainly found in Antartica and Greenland

Found in mountainous areas around the world like: North America, Chile, Europe and Asia (Himalayas)

Question 39

Define permafrost

Answer 39

Is soil and rock which remains frozen as long as temperatures do not exceed 0 degrees Celsius

Question 40

Define :

i. Continuous Permafrost
ii. Discontinuous Permafrost
iii. Sporadic Permafrost

Answer 40

Forms in the coldest areas in the world where it can exceed downwards hundreds of metres

More fragmented and thinner

Occurs in periglacial environments and is very fragmented

Question 41

What is the active layer

Answer 41

The top layer of soil in permafrost environments that thaws during the summer and freezes during the winter

Question 42

Explain the periglacial process of Nivation and the effect it has on the landscape

Answer 42

When a combination of freeze thaw weathering, chemical weathering and solifluction causes nivation hollows to form and increase in size.
Eventually the nivation hollow gets so big that glacial ice forms and it forms a corrie

Question 43

Explain the periglacial process of frost heave and the effect it has on the landscape

Answer 43

Is a process which forms patterned ground
Happens due to the freezing and expansion of soil water causing the upward movement of soil and rock.
Stones are heaved upwards and cause stone polygons or strips to form on the surface.

Question 44

Explain the periglacial process of solifluction and the effect it has on the landscape

Answer 44

Solifluction forms solifluction lobes
This happens when the active layer becomes over saturated and water cannot percolate as its on top of permafrost.
The active layer moves downwards,due to gravity, and forms a solifluction lobe

Question 45

Explain the periglacial process of ground contraction and the effect it has on landscapes

Answer 45

Is a process which forms ice wedge polygons.
This happens when extremely low temperatures cause the ground beneath the active layer to crack.
Glacial meltwater enters the crack and expands due to freeze thaw weathering
Ice wedges form in the cracks and cause rock and sediment to be lifted upwards forming patterned ground

Question 46

Explain aeolian action (loess)

Answer 46

Wind is able to pick up and transport dry sediment from the grounds surface, due to limited vegetation cover

Extensive accumulations of wind deposits are called loess

Question 47

Explain meltwater erosion (braiding)

Answer 47

Where meltwater is created by thawing in the summer. It erodes the river channel causing high discharge.

The drainage pattern near the margins of glaciers is braided as high amounts of debris is carried.

Question 48

What is groundwater freezing

Answer 48

Where water is able to filter into the upper layer of the ground and freeze causing an ice cored dome to form, called a pingo