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)
Shape: controlled by the mountain topography, and follows the liquid-water paths in valleys
Volume: less volume than Continental
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)
Shape: large, and bull-dozer like
Volume: high volume compared to Alpine
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:
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:
Fresh snowflakes
Few day old snow (nobular)
Geometric Firn
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