Glaciated Landscapes EQ 1

Question 1

Current estimation of earths age

Answer 1

4.6 billion years old

Question 2

The two states the earth fluctuates between

Answer 2

Icehouse earth and greenhouse earth

Question 3

What is greenhouse earth

Answer 3

A period when there are no continental glaciers and CO2 and other gases are high.

Question 4

What is icehouse earth

Answer 4

A period in which ice sheets wax and wane through glacial and interglacial periods. Greenhouse gases are less abundant and temperatures are cooler globally.

Question 5

Two climate fluctuations during icehouse earth

Answer 5

Interglacial and glacial

Question 6

What is glacial

Answer 6

A period of time where ice advances

Question 7

What is interglacial

Answer 7

A period of time where ice retreats

Question 8

What is stadial

Answer 8

Happens only in a glacial and it is when there is a massive advance in ice.

Question 9

What is interstadial

Answer 9

Happens only in a interglacial period an it is when there is a massive retreat in ice

Question 10

What is a Pleistocene and what was the most recent one

Answer 10

The most recent glacial which is called the Loch Lomond satdial.

Question 11

What is a Holocene and what is the most recent one

Answer 11

It is the last interstadial which is called the little ice age

Question 12

What are the 3 smaller cycles in the milankovitch cycles

Answer 12

Eccentricity
Obliquity
Procession of the equinoxes

Question 13

What happens in eccentricity

Answer 13

The earth orbit changes from circular to elliptical over a 100,000 year cycle

Question 14

What happens in the obliquity cycle

Answer 14

When the tilt of the earth varies from 21.5⁰ to 24.5⁰ obra 41,000 year cycle.

Question 15

What happens in the precession of equinoxes

Answer 15

When the earth wobbles as it spins on its axis and causes seasons to vary. The earth can be tilted away or towards the sun. This happens over a 21,000 year cycle.

Question 16

How panama isthmus caused long term climate change

Answer 16

When the North American plate and the South American plate collide forming panama isthmus. This caused the warm currents that once flowed in between to flow north, creating the Gulf Stream. The Gulf Stream transports warm water to the arctic providing extra moisture for snow fall. This triggered the build up of Greenland’s ice sheet which of may of kick started the ice age.

Question 17

2 short term causes of climate change

Answer 17

Volcanic emissions and variation in solar out put

Question 18

How do volcanic emissions cause short term climate change

Answer 18

Volcanoes inject large amounts of sulfur dioxide into the atmosphere which remains there for as long as 3 years. Sulfate aerosols are formed which increases the reflection of radiation from the sun cooling the earth. Also ash block solar radiation but returns to earth within months.

Question 19

How does variation in solar output cause climate change

Answer 19

Dark patches on the surface of the sun are called sun spots. They are caused by intense activity in the suns interior. An increases in spots means the sun is more active and giving more energy. This varies over a 11 year cycle.

Question 20

Define cryosphere

Answer 20

Cold environments of our planet where water is in it’s sold of form of ice

Question 21

What is the importance of the cryosphere

Answer 21

• Cryosphere impacts climate change with snow and ice having a high albedo affect, protecting earth from extreme global warming by reflecting solar radiation.
• Snow and ice are good insulators, holding in heat and moisture which will escape the sea or land into the atmosphere. This cools the global climate as warm water from the tropic that circulate at the poles does not escape.
• Cold seawater can hold more salt so it sinks, spreading out across the globe and acting as a pump.

Question 22

What are the 7 types of ice masses (classification by location and scale)

Answer 22

Cirque 
Ice sheet 
Ice-shelf
Ice cap
Ice field 
Valley glacier 
Piedmont

Question 23

Description of a cirque and is constrain or unconstraint

Answer 23

An armchair shaped hollow with a steep back wall, formed as a result of glacial erosion. Often containing a rock basin or tarn. It is constraint. 0.5-80km²

Question 24

Describe an ice sheet and is constrain or unconstraint

Answer 24

A mass of ice and snow of considerable thickness and has to cover 50,000km². It is unconstraint.

Question 25

Describe ice shelf and is constrain or unconstraint

Answer 25

A large slab of ice floating on the seas but remaining attached and largely fed by land derived ice. It is unconstraint. 10,000-100,000km²

Question 26

Describe ice caps and is constrain or unconstraint

Answer 26

A domed shaped mass of glacier ice, situated in a highland area. It is unconstraint. Up to 50,000km²

Question 27

Describe a valley glacier and is constrain or unconstraint

Answer 27

A glacier bounded by the walls of a valley and descending from mountains, ice cap or ice sheet. It is constraint. 3-300km²

Question 28

Describe a piedmont and is constrain or unconstraint

Answer 28

A glacier that spreads out as a wide lobe as it leaves the narrow mountain valley to enter a wider valley or plain. It is unconstraint. 3-1000km²

Question 29

Describe ice fields and is it constrains or unconstraint

Answer 29

Similar to ice caps but are typically smaller. They don't cover topography. They are unconstraint and are under 50,000km²

Question 30

Classifying by polar climates

Answer 30

Is where the ice is frozen to the base so there is very little movement. As there is little moment there is not much erosion. As there is no lubrication from meltwater. An example of a glacier would be princess Elizabeth land which is an unconstraint ice shelf in the Antarctic with a size of 437,000km²

Question 31

Classifying by temperate climate

Answer 31

Is where the base is above melting point from geothermal energy and friction. As the base is above melting point ice melts creating meltwater. The meltwater acts as a lubricant making it earlier for ice to slide and erode. An example would be an Alpine valley glacier such a mer de glacé and constraint glacier in the alps which is 0.5km wide, 1.5km thick and 7km long

Question 32

What are tundra environments

Answer 32

Are environments characterised by permafrost and found at high latitudes in the north. They are found in the north because the suns rays hit at an angles. This means solar radiation is spread over a larger area making it cooler.

Question 33

Where are ice sheet found and how are they formed

Answer 33

They are found at Greenland an Antarctica. They are found here because snow that falls in the water doesn't completely melt in the summer and over time this builds up.

Question 34

What is a alpine glacial

Answer 34

They are found at high altitudes and can be found across the world. They tend to be high up in the mountains such as the Himalayas for alps. They are found at high altitudes because the higher you are the lower the pressure. This means gas is more spread out and has low kinetic energy, lowering temperature. There is also more moisture so more snow.

Question 35

Define periglacial

Answer 35

Places where the temperature is frequently below or constantly below 0 but not covered by ice. They contain a layer of permafrost on or below the surface.

Question 36

What is the distribution of periglacial landscapes

Answer 36

They are found at high altitudes, high altitudes and the interior of land masses. They are found in the interior of land masses because of continentality, this where the interior doesn't benefit from the warm ocean currents in the winter.

Question 37

What is continuous permafrost

Answer 37

Found at high latitudes so it has a low mean average temperature and low active layer with a deep depth of permafrost.

Question 38

What is discontinuos permafrost

Answer 38

Is found at a lower latitude so it has a high mean temperature and a high active layer with a deep depth of permafrost.

Question 39

Sporadic permafrost

Answer 39

Is found at the lowest latitudes of the 3 meaning there is a high mean temperature and the highest active layer with a small depth of permafrost.

Question 40

What are the glacial erosional processes

Answer 40

Abrasion Plucking Crushing Basal melting

Question 41

What is abrasion

Answer 41

Is when material rubs against The Valley sides and floor wearing the away by a process similar to sandpaper.

Question 42

What is plucking

Answer 42

When melt water freezes part if the underlying bedrock to the base. Any loose rock fragments are plucked away as the glacier slips forward.

Question 43

What is crushing

Answer 43

The direct fracturing of weak bedrock by the weight of ice above it.

Question 44

What is basal melting

Answer 44

Large volumes of meltwater can cause fluvial erosion processes such as abrasion, hydraulic action, attrition and corrosion.

Question 45

What are the different types Periglacial processes

Answer 45

``` Solifluction Nivation Frost heave Meltwater erosion Freeze thaw ```

Question 46

What is solifluction and how are solifluction lobes formed

Answer 46

Is the downward movement if rock and material in responde to gravity. Summer thaw on the active releases a great deal of meltwater. The water is unable to percolate downwards as the ground is frozen and impermeable. It saturates the soil reducing internal friction between particles making it highly mobile. The lack of vegetation to fix the soil means it begins to move on a few degree slope. Solifluction lobes are tongue like features forming terraces. These stepped features form beneath turf which is pushed and rolled under. Where there is sparse vegetation, stones are heaved onto the surface.

Question 47

What is nivation and how are nivation hollows formed

Answer 47

When snow gets into a hollow and temperatures fluctuate and freeze thaw occurs. Freeze thaw and even possibly chemical weathering causes underlying rock to disintegrate. As some of the snow melts in the spring the rock debris is moved downslope by meltwater and solifluction. Over time the hollows enlarge becoming wider and deeper.

Question 48

What is frost heave

Answer 48

The freezing and expansion if soil water causing upward dislocation of soil and rock. As the ground refreezes and expands it pushes up stones forming small domes.

Question 49

How are ice wedge polygons formed

Answer 49

They are formed when the refreezing of the active layer during the winter causes the soil to contact (ground contraction). Cracks open up on the surface and during the following summer melt water and fine sediment fill the cracks. This happens repeatedly through the cycle of winter and summers widening and deepening the crack to form an ice wedge. The cracking produces a polygon pattern. When a ice wedge melts it may fill with sediment forming an ice wedge cast.

Question 50

How are loesses formed

Answer 50

They are formed by aeolian action where there is limited vegetation cover. The wind is able to pick up and transport fine sediment from the ground surface. Extensive accumulation of wind blown deposits are known as loess

Question 51

How are pingos formed

Answer 51

Formed when water filters down into the upper layers of the ground and then freeze, the expansion of ice cause the overlying sediment to be heavier upwards into a dome which may rise as high as 50m.