Lecture 1

Question 1

What is a glacier made up of?

Answer 1

Fallen snow that, over the years compresses into firn and then ice

Question 2

How does a crevasse form?

Answer 2

Glaciers deform and flows under gravity
The ice cracks because it experiences stress from the topography or ice flow obstacles.

Question 3

Where are present-day glaciers located?

Answer 3

In regions of high latitude (60-90º) and high altitude (> 3 km above sea level): Where the balance between air temperatures (ablation) and precipitation rates (accumulation) ensures the survival of the ice/snow throughout the year.
North American Cordillera, Atctic Ilands, Scandinavian Mountains, Third Pole Region, The European and New Zealand Alps, The Andes and the Antarctic

Question 4

What are the preconditions for the existence of glaciers?

Answer 4

Cold temperatures and sufficient precipitation (snow)

Question 5

Why is it cold in the high mountains?

Answer 5

Because of the lapse rate at which the temperature in Earth’s atmosphere decreases with altitude. When air particles rise to a higher elevation, they experience lower pressure and expand, losing heat and cooling adiabatically.

Question 6

Why is it cold at high latitudes?

Answer 6

Cold climate is maintained by
1) low incoming solar energy and
2) high albedo of snow and ice.
Polar regions receive only 34% of solar energy compared to the equator because the same amount of energy is distributed over a larger area, and the sun’s rays lose more energy to the atmosphere.

Question 7

How does the albedo affect polar regions during the year’s warmest months?

Answer 7

Snow reflects 80-95% of all incoming energy; when the snow starts melting in June, wet soils and water bodies are exposed (absorb 75-97% of incoming heat) and further warm the artic.

Question 8

What is albedo?

Answer 8

Albedo is the measurement of the reflection of a surface or a body