Glacier Dynamics and Movement

Key Concepts

• Glacial Ice as a Fluid
  • Despite being solid, glacial ice flows like a river.
  • Driven by the sheer weight of the ice pack.
  • Glaciers are formed by layers of snow compacted into ice.

Glacier Structure and Movement

• Size and Scale
  • Glaciers can be over nine kilometers long and up to 500 meters deep.
  • Millions of tonnes of ice contained within a valley.
• Movement
  • Movement is slow but perceptible via time-lapse cameras.
  • Surface ice travels approximately 275 meters per year.
  • The glacier carves away rock as it moves.

Ice Surface Features

• Crevasses
  • Created by the brittle, tough surface ice breaking open.
  • Indicate movement of the glacier.

Meltwater and Internal Glacial Changes

• Meltwater Role
  • Gather in crevasses and hollow its way towards bedrock.
  • Carves out caverns within the glacier.
  • Lubricates glacier's base, aiding in its movement.
• Temperature and Climate Impact
  • The temperate mountain climate keeps lower glacier ice close to melting point.
  • Meltwater within the ice influences internal dynamics.

Observations and Explorations

• Exploring the Glacier's Heart
  • Abseiling into the glacier reveals the dynamic nature of the ice.
  • The interaction of ice and meltwater is crucial to glacial movement.
• Transient Nature
  • Ice caves and structures can change yearly, indicating a constantly changing glacier.
  • The glacier's dynamic and transient features underscore its constant movement.