Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ESCI 111 > Glaciers > Flashcards

Glaciers Flashcards

1
Q

How much is sea level expected rise by 2024?

A

It is expected there will be a 0.4m increase in sea level rise.

Currently, there is a 3mm increase.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why is the sea level rise uneven?

A

When a glacial/ice sheet melts, the sea level rise is uneven.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the sea level equivalence (SLE) of:

Glacier + ice sheets
Greenland
West Antarctica
East Antarctica

A

Glacier + ice sheets = 0.6m of SLE
Greenland = approx 65m of SLE
West Antarctica = 7.3 of SLE
East Antarctica = 53.3 of SLE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is one of the largest contributors to sea-level rise?

A

Sea Level Equivalence (SLE) and thermal expansion of the ocean.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many people will be displaced in Bangladesh due to sea-level rise?

A

It will displace 17 million people.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define glacier…

A

A flowing mass of ice formed from compacted snow lasting multiple winters and summers.

(due to equilibrium and mass balance)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are New Zealand’s glacier?

A
  1. Franz Josef glacier

2. Tasman glacier (1/3 of NZ’s glaciers - largest). it has fine grains + boulders.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How ice formed (the process)?

A
  1. Snow falls
  2. Compacts (ice bubbles of present atmosphere gas become climate records)
  3. Turns into firn
  4. Turns into ice
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is firn?

A

It is snow that has been transformed and begun the process of becoming ice.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is never denser than water?

A

Ice. (always floats).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does equilibrium mean?

Hint: For glaciers

A

It is the steady state, the inputs balance the outputs, net mass balance = zero.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens if the inputs and outputs change?

A

Change the inputs and outputs and the glacier must reach a NEW EQUILIBRIUM.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does more accumulation mean?

A

More accumulation means the higher the elevation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

For the end of summer survey, what does it mean if the snow is above or below the cross-section of the glacier?

And what is it dependent on?

A 
Above = Snow will turn into ICE
Below = Snow will MELT

No snow in summer = NO ice

Dependent on TOPOGRAPHY and DIRECTION of avalanches.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does response time mean?

A

It is the time a glacier takes to adjust to a change in MASS BALANCE.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the equation to work out the response time?

A

t = H/ao

t = response time
H = maximum thickness
ao = frontal ablation rate

17
Q

What does the front of the cross-section/frontal lobe of the glacier tell us?

A

What you see at the front, doesn’t tell you what has happened in the past.

18
Q

What does it mean if a large iceberg leaves/falls off and the front is the same?

A

It means that the glacier is still in mass balance.

19
Q

What are the calving process?

A
  • Responsible for 1/2 mass loss in ANTARCTICA.
  • STRETCHING due to velocity gradients (like stretching playdough, can only stretch so far before breaking).
  • Force imbalance near ice cliffs.
  • Cliffs undercut by melt BELOW waterline.
  • Buoyant forces causing TORQUE.
20
Q

Where on/around the glacier experiences the fastest velocity?

A

On the surface.

21
Q

Where on/around the glacier experiences the slowest velocity?

A

At the bottom of the bedrock.

22
Q

What caused the Tasman Glacier to calve?

A

Tasman glacier full-face buoyant is driven by calving event.

  • Torque causing it to turn up and create fractures.
  • Doesn’t happen frequently.
23
Q

What is internal deformation?

A

Layered structures and folding = deformation

E.g. Glacier flow resulting from the deformation of glacier ice under the influence of accumulated snow and firn, and of gravity. There can be LAYERED structures and FOLDING resulting from internal deformation in the terminal cliff of Crusoe glacier.

24
Q

How is glacier sliding carried out?

A
  1. Regulation + enhance creep.

(heat flow from low to high pressure and water flow in the opposite direction).

Low pressure = refreeze
High pressure = melt

  1. Englacial + subglacial water flow
    Englacial channels will from PERPENDICULAR to lines of EQUIPONTETIAL.
    Channels within the ice will CONVERGE due to lower pressure in larger channels.
25
Q

What is the relationship between air temperature and velocity?

A

An increase in temperature will increase velocity.

26
Q

How to tell if glaciers are in a changing climate?

A
  1. Look at the front space (geodetic mass balance).

2. Measure the front (frontal position of the glacier).

27
Q

What is an ice sheet?

A

An ice sheet is an extensive (continental scale) region of PERMANENT ice cover.

E.g. Greenland, West + East Antarctica.

28
Q

What is a marine ice sheet?

A

It is an ice sheet that is GROUNDED well BELOW sea level.

E.g. West Antarctica (Earth’s only one).

29
Q

What is an ice stream?

A

An ice stream is a FAST moving ice bounded by SLOWER moving ice (as apposed to a glacier that is bounded by rock). It is long.

ESCI 111 (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions