Greenland

Question 1

What is the potential for sea level rise?

Answer 1

7.3 meters.

Question 2

What are the 2 main causes of ice loss?

Answer 2

Negative surface mass balance

Accelerated discharge from marine terminating glaciers

Question 3

What happened in 2012?

Answer 3

Whole of Greenland reached pmp

Question 4

Case Study - Peterman glacier

Answer 4

Outlet glacier
2012, calving event removed 25km of ice from tongue.
Ice tongues subject to high rates of basal melt.
Tongue weakens.

Question 5

What is the runaway effect (Parizek & Alley, 2005)

Answer 5

Melt water = basal sliding = acceleration = stretching of glacier profile = ablation zone increase = crevasses and drainage.

Question 6

Name 3 factors that control melt

Answer 6

Salinity, ocean temperature and velocity.

Question 7

What causes meltwater plooms?

Answer 7

Warm, sub-tropical water circulates at depth near glacier front.
Polar water, flows close to surface.
Air temperature accelerates rates of submarine melting.
Surface melt, drains through glacier, exits at depth and mixes with cold water.

Question 8

How does sea ice reduce calving?

Answer 8

Holds glacier and terminus in place.

Question 9

Jakobhavn

Answer 9

Outlet glacier drains 6% of Greenland.

Retreated past pinning point and lost ice tongue in 2003. Ocean warming as cause.

Question 10

How much does North Greenland drain?

Answer 10

40% of whole ice sheet.

Question 11

Varying retreat rates. Example

Answer 11

Alison glacier retreated 10km in 4 years. Carr (2013). Shows that retreat rates very individually.

Question 12

Zwally (2002)

Answer 12

Drainage of supraglacial lakes in ablation zone provides water at base.
Force of draining causes hydro fractures, water can reach bed.

Question 13

Types of numerical modelling

Answer 13

Prognostic - look at most processes. Aim to predict future by looking at past.

Diagnostic - look to focus on specific feature or process to see its effect.