levo

Glaciated Landscapes

Firn, glacier ice, valley glaciers and ice sheets

  • 3 things to know
  • Component 01

Overview

Recall questions on how snow becomes firn and then glacier ice, the densities involved, why glacier ice looks blue, the role of meltwater, and valley glaciers, ice caps, piedmont glaciers and the Antarctic and Greenland ice sheets.

What you need to know

Answer each one before you reveal it.

Your recallNot started
Key term

What is firn?

Process

Outline the stages by which fresh snow becomes glacier ice.

Key term

Why does dense glacier ice appear blue?

Questions from this subtopic

Each one with the model answer underneath.

  1. 1

    What is firn?

    Model answer

    Firn is snow that has survived at least one summer melt season and has been compacted into a dense, granular mass.

  2. 2

    Outline the stages by which fresh snow becomes glacier ice.

    Model answer

    Fresh snow is compressed and its crystals round off, air is squeezed out to leave firn, and continued burial with melting and refreezing turns the firn into dense glacier ice.

  3. 3

    What is the approximate density of freshly fallen snow?

    Model answer

    About 50 to 100 kg m⁻³.

  4. 4

    State the approximate density of glacier ice.

    Model answer

    About 900 kg m⁻³.

  5. 5

    At what density is compacted snow regarded as having become glacier ice?

    Model answer

    At about 830 kg m⁻³, when the air passages between grains seal off into isolated bubbles.

  6. 6

    Why does dense glacier ice appear blue?

    Model answer

    Bubble-free ice absorbs the longer red wavelengths of light and scatters the shorter blue wavelengths back to the observer.

Other ways to work this

The same content, four other ways.

What is inside Levo

Six ways to work the same material.

1Closed book
2Open book
3Closed book

The 3-step method, run for you

Answer cold, learn it, then prove it stuck. Levo tracks the jump between your first attempt and your last.

Coastal Landscapes
Glaciated Landscapes
Dryland Landscapes
Earth’s Life Support Systems

Cram a whole paper in one sitting

Sort every topic into what you know and what you do not, then drill only the weak ones.

Hotter magma is .
runnierthickerslower

Blank Blitz makes facts automatic

Rapid timed gap-fills on the terms and numbers you need to recall without thinking.

AThe lower quartile is the 2nd value, 11 cm.
BThe upper quartile is the 6th value, 16 cm.
CThe interquartile range is 16 − 11 = 5 cm.

Build It gets the exam shape right

Assemble a full-mark answer from its marking points, in the order an examiner wants them.

The sunspot cycle lasts about 11 years.
TrueFalse

Test It catches misconceptions

Spot the fault in a statement. The traps are the mistakes students actually make.

721941163128510

Brain Breaks between sessions

Short focus games to reset attention, so the next set lands better than the last.

Every question in Glaciated Landscapes, on a schedule.

Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.

Or £46 a year, about £3.83 a month. Cancel anytime.