EO

Glaciers

Glacier: ice mass that forms on land from the accumulation, compaction and recrystallization of snow

  • must have movement or flow (from the accumulation area towards the ablation area) (gravity driven)

  • 68.9% of fresh water is in glaciers

Are responsible for erosion, land formations, and some soil origins

  • flat, fertile lands in the midwest

Regulate climate change

  • Albedo: proportion of light or ration reflected by a surface

  • warm temperatures melt ice, less ice increases in warm temperatures = reinforcing loop

Glacier Types: Alpine and Continental

Alpine: formed in mountains, smaller, don’t move much, and located in more temperature areas (the alps)

  1. Shape: controlled by the mountain topography, and follows the liquid-water paths in valleys

  2. Volume: less volume than Continental

  3. Impact: erodes the sides of the mountain, they pick up material, and turns mountain valleys from V-shaped to U-shaped

Continental: formed over broad area, sheet like, and cover large distances (Greenland and Antarctica)

  1. Shape: large, and bull-dozer like

  2. Volume: high volume compared to Alpine

  3. Impact: responsible for midwest landscape formation, pick up and drop large volume of material. They stop moving when they get to a warm enough region, and they start to retreat

Gracier Loss:

  1. Greenland has a smaller ice mass and faster ice mass loss

    • due to warmer latitude and less mass, making it easier to loose volume

    • most water ends up in oceans, becoming salt water, which can lead to increased sea levels and sea water dilution

Formation of Glacier

Glacier Growth: added snow exceeds melting and sublimation

  • currently in high latitudes and in high mountains

  • precipitation at the beginning and high end of the glacier, along with input accumulation and the midsection of the glacier

  • output and melt/retreat and the end of the glacier

Glacial Ice Formation:

  1. Fresh snowflakes

  2. Few day old snow (nobular)

  3. Geometric Firn

  4. Compaction of firn (which has trapped atmosphere and water) = glacial ice

    • the trapped atmosphere acts as a record of global CO2

Flow and Velocity

Flow: glaciers slide along the base, which can be accelerated by meltwater

Velocity: highest at the top and center, slowest and the bottom and edges

Glacial Rebound

Glaciers can impact the overall mass of continental crust its resting on, causing mantle ot sink down

  • when glacier melt, the mantle and subsequent continental crust uplifts

  • can impact sea-level rise