Glaciated Landscapes: Periglacial Environments

Question 1

What defines a periglacial environment?

Answer 1

An area with permafrost, some seasonal temperature variation with summer temperatures above 0 degrees celsius (not year-round subzero temperatures), where freeze-thaw cycles dominate the landforms formation, and which have a distinctive adapted ecosystem

Question 2

What is permafrost?

Answer 2

Permanently frozen ground where soil temperatures are below 0 degrees celsius for at least 2 years

Question 3

What is continuous permafrost?

Answer 3

Summers so cold that surface melting is superficial and with permafrost that reaches 1500 metres, with mean air temperatures below -5 degrees celsius year-round and as low as -50 degrees celsius

Question 4

What is discontinuous permafrost?

Answer 4

Slightly warmer areas due to surface water, which have small pockets of unfrozen ground within the permafrost and annual temperatures of between -1 and -5 degrees celsius

Question 5

What is sporadic permafrost?

Answer 5

Found when mean annual temperatures are just below 0 degrees celsius, and summer temperatures reach several degrees above, but pockets of permafrost remain below the surface

Question 6

What is the active layer?

Answer 6

A mobile layer due to sufficient summer temperatures causing surface melting, which can vary in thickness depending on vegetation cover, latitude and climate

Question 7

What is talik?

Answer 7

Unfrozen material within the permafrost zone