Key Definitions

Question 1

Ablation

Answer 1

The loss of mass from a glacier eg. Meltwater, avalanches, sublimation, evaporation

Question 2

Abrasion

Answer 2

Small rocks within the base of the glacier rub against the bedrock

Question 3

Accumulation

Answer 3

The addition of mass to the glacier, usually as snow

Question 4

Active layer

Answer 4

The top layer of soil above permafrost, which thaws annually in summer

Question 5

Alpine regions

Answer 5

Areas of low temperature in high altitude, mountainous regions

Question 6

Basal ice melting

Answer 6

The weight of a temperate glacier causes meltwater, which will then erode the bedrock through fluvial erosion

Question 7

Basal sliding

Answer 7

Glaciers sliding over bedrock, due to meltwater between the 2 surfaces

Question 8

Cold based glacier

Answer 8

The glaciers temperature remains below 0C so the base of the glacier remains frozen and moves very little

Question 9

Compressional flow

Answer 9

Ice builds up and thickens due to friction as a glacier travels upwards along a shallow gradient

Question 10

Crushing

Answer 10

The weight of the glacier causes fracturing in the bedrock

Question 11

Environmental fragility

Answer 11

An environment is vulnerable or at risk, with low resilience or ability to adapt to changes

Question 12

Extensional flow

Answer 12

Ice thins out, creating crevasses, due to an increase in the glaciers velocity down a shallow gradient

Question 13

Fluvial erosion

Answer 13

Water within the glacier erodes the base of the glacier over time

Question 14

Frost heave

Answer 14

The freezing and expansion of water beneath the ground, resulting in floor uplift

Question 15

Glacial budget

Answer 15

The difference between accumulation and ablation for a glacier

Question 16

Glacial period

Answer 16

A period of time of colder average global temperatures causing the growth of ice cover, glacial advances and sea levels to fall

Question 17

Holocene epoch

Answer 17

Our current glacial period of limited ice cover, lasting over 10,000 years

Question 18

Interglacial period

Answer 18

A period of time of warmer average global temperatures, resulting in reduced ice cover, glacial retreat and sea levels to rise

Question 19

Internal deformation

Answer 19

Glacial movement caused by the weight of the glacier above deforming the ice

Question 20

Milankovitch cycles

Answer 20

Changes to the tilt and shape of the orbit will affect the average temperature of the Earth

Question 21

Nivation

Answer 21

Erosional process involving snow and ice

Question 22

Orbital eccentricity

Answer 22

How far a planets orbit is from being a perfect circle

Question 23

Periglacial

Answer 23

Landscapes found at the edge of a glacier, polar and alpine regions. Permafrost occurs, with low precipitation and only highly adapted plant species survive

Question 24

Permafrost

Answer 24

Permanently frozen soils for a period of 2 years or longer

Question 25

Plucking

Answer 25

Rocks on the bedrock are frozen within the glacier. As the glacier moves, the rocks are pulled from the bedrock and moved

Question 26

Polar regions

Answer 26

Areas of maximum ice sheets and limited vegetation, located at high altitudes on earth

Question 27

Solifluction

Answer 27

The movement of waterlogged soil, trapped between the active layer and permafrost

Question 28

Warm based glacier

Answer 28

Faster travelling glaciers due to basal meltwater trapped underneath the glacier, acting as lubrication to allow the glacier to move

Question 29

Striation

Answer 29

Scratches or grooves that are found on the surface of rocks, created by the movement of glacial ice