Glaciated Landscapes Unit 1

Question 1

What is a glacier?

Answer 1

A glacier is a moving dense body of ice that is constantly moving downhill under its own weight

Question 2

What are the key components of the glacial system?

Answer 2

Inputs, outputs, stores, and transfers of energy and materials.

Question 3

What does the glacial budget include?

Answer 3

The glacial budget describes how ice accumulates and melts on a glacier which ultimately determines whether a glacier advances or retreats

Question 4

What are the two zones of a glacier?

Answer 4

• Zone of accumulation
• Zone of ablation

Question 5

What happens if inputs to a glacier exceed outputs?

Answer 5

The glacier will grow (advance).

Question 6

What happens if outputs exceed inputs in a glacier?

Answer 6

The glacier will shrink (retreat).

Question 7

Fill in the blank: When snowflakes fall, they contain _______ and have a low density.

Answer 7

air

Question 8

What is firn?

Answer 8

Compacted snow that has experienced one winter’s freezing and a summer’s melting.

Question 9

What is the mass balance of a glacier?

Answer 9

The difference between inputs (accumulation) and outputs (ablation).

Question 10

What are the three mechanisms identified by Milutin Milankovitch that affect Earth’s climate?

Answer 10

• Stretch (eccentricity) of orbit
• Axis Tilt (obliquity)
• Wobble (precession)

Question 11

What is the significance of the Younger Dryas?

Answer 11

A rapid period of cooling towards the end of the last glacial period (Devensian) in the Northern Hemisphere.

Question 12

True or False: The Earth’s current axial tilt is 23.5 degrees.

Answer 12

True

Question 13

What factors determine the mass balance of a glacier?

Answer 13

• Inputs (accumulation)
• Outputs (ablation)

Question 14

What are the conditions required for glacier formation?

Answer 14

Cold temperatures and sufficient snowfall.

Question 15

What is the zone of equilibrium in a glacier?

Answer 15

The area where inputs equal outputs.

Question 16

Fill in the blank: The long-term cyclical change between glacial and interglacial periods is mainly due to changes in the Earth’s _______.

Answer 16

orbit

Question 17

What is meant by a positive feedback loop in the context of glaciers?

Answer 17

The decrease in temperature allows more glacial growth, which reflects more radiation and further reduces the temperature. This positive feedback loop allows glaciers to grow and grow, reducing the global temperatures. Glacier growth —> increased albedo —> decreased temperature —> more glacier growth

Question 18

What is the impact of increased snow and ice cover on climate?

Answer 18

It raises surface albedo, reflecting more solar energy back to space instead of warming the planet

Question 19

What is the primary cause of long-term climate change over hundreds to thousands of years?

Answer 19

Milankovitch cycles’ variations in insolation.

Question 20

What are the consequences of a negative mass balance in glaciers?

Answer 20

Glaciers shrink and retreat.

Question 21

What is calving in the context of glaciers?

Answer 21

The break-away of ice blocks from the end of the glacier

Question 22

Fill in the blank: The Earth’s orbit varies between _______ and elliptical.

Answer 22

circular

Question 23

What are the two types of feedback mechanisms in long-term climate change?

Answer 23

• Positive feedback - temp rise - amplifies global warming
• Negative feedback - temp decreases - diminished global warming

Question 24

What happens to the glacier mass balance during the winter?

Answer 24

Inputs exceed outputs, leading to accumulation.

Question 25

What happens to the glacier mass balance during the summer?

Answer 25

Outputs exceed inputs, leading to ablation.

Question 26

What is the Younger Dryas?

Answer 26

A rapid period of cooling at the end of the last glacial period due to disruption of ocean currents in the North Atlantic Occurred during a time of rising temperatures - disrupted trend

Question 27

What significant temperature drop occurred during the Younger Dryas?

Answer 27

A drop in temperature in Central Greenland to -16C

Question 28

What is solar forcing?

Answer 28

Solar forcing refers to energyreleased by the sun linked to sun spot activity Sun spots fluctuate on an approximate 11-year cycle.

Question 29

What historical period is referred to as the Maunder Minimum?

Answer 29

A period between 1645 and 1715 characterized by low solar output This period contributed to the Little Ice Age.

Question 30

What were some impacts of the Maunder Minimum?

Answer 30

* Sea ice expanded into the Atlantic * Frost Fair occurred on the River Thames * Baltic Sea and many European rivers froze over * Permanent snow cover in Scotland's Cairngorm Mountains at an altitude of 1200m * Glaciers advanced in the Alps These impacts reflect significant climate alterations during this period.

Question 31

How do volcanic eruptions influence climate conditions?

Answer 31

Explosive eruptions propel sulfur dioxide and ash into the stratosphere, reflecting solar radiation Eruptions of VEI >4 have significant cooling effects.

Question 32

Name two significant volcanic eruptions and their effects.

Answer 32

* Laki (Iceland, 1783) - caused winter of 1783–1784 to be 3°C below average * Tambora (Sumbawa Island, 1815) - reduced global temperatures by up to 0.7°C for 2-3 years These eruptions illustrate the impact of volcanic activity on climate.

Question 33

What is the current trend in global average temperatures since 1880?

Answer 33

An increase of over 1.2°C This rise is attributed to anthropogenic factors increasing greenhouse gas concentrations.

Question 34

How much of the Earth's land surface is covered by glaciers?

Answer 34

More than 10% Glaciers store 75% of the world's fresh water.

Question 35

What is meant by positive mass balance in the context of glaciers?

Answer 35

When the accumulation of ice exceeds ablation This results in glacier growth.

Question 36

What is a negative mass balance?

Answer 36

When ablation exceeds the accumulation of ice This leads to glacier retreat.

Question 37

Where are glaciers typically found?

Answer 37

* High altitude regions * High latitude regions Glaciers require specific conditions for formation and maintenance.

Question 38

Define equilibrium line in the context of glaciers.

Answer 38

The altitude at which the accumulation of snow equals the ablation This line indicates the balance point of a glacier.

Question 39

What is albedo?

Answer 39

The measure of reflectivity of a surface High albedo surfaces reflect more solar energy, influencing local climate.

Question 40

Fill in the blank: The current distribution of ice is contrasted with the _______ maximum from 18,000 years ago.

Answer 40

Devensian The Devensian maximum represents a significant glacial period.

Question 41

What changes in ice cover have occurred over long time periods?

Answer 41

The amount of ice cover over the Earth has varied greatly due to cumulative mass balances These changes impact global sea levels and ecosystems.

Question 42

True or False: Glaciers today are primarily found in low altitude regions.

Answer 42

False Glaciers tend to be found in high altitude and/or high latitude regions.

Question 43

How is Europe 18000 years ago different to today?

Answer 43

Extent of ice masses: ice almost completely covered northern regions of Europe such as Norway, Sweden and Scotland Impacts of sea level on coastlines: since then due to ice melting from moving into an interglacial period the sea levels have risen, meaning there is no longer land between France Sea ice extent: the sea ice quantity is much more vast 18000years ago compared to today