Dynamic Planet Notes

Science Olympiad: dynamic planet glacier competition

Glaciers

Large masses of ice that form from the accumulation and compaction of snow over time and flow under their weight.

Ice Sheets

Massive, continent-sized glaciers covering areas larger than 50,000 km²; only two exist today: Greenland Ice Sheet and Antarctic Ice Sheet.

Accumulation zone

Area where snowfall adds to the glacier.

Ablation zone

Area where ice is lost through melting, sublimation, or calving.

Equilibrium line

Boundary where accumulation equals ablation.

Basal sliding

Movement at the glacier's base, often lubricated by meltwater.

Internal deformation

Flow within the ice due to pressure differences.

Crevasses

Cracks on the surface caused by differential flow rates.

Cirques

Bowl-shaped depressions at the heads of glaciers.

Arêtes

Sharp ridges formed between two cirques.

Horns

Sharp mountain peaks sculpted by glaciers.

Moraines

Ridges of debris deposited by glaciers, including types such as lateral and terminal.

Esker

Sinuous ridges formed by sediment deposition in subglacial streams.

Drumlins

Elongated hills formed beneath glaciers, indicating ice flow direction.

Albedo Effect

Ice reflects solar radiation, cooling the Earth.

Positive mass balance

Condition when a glacier gains ice and grows.

Negative mass balance

Condition when a glacier loses ice and shrinks.

Plucking

Process where glaciers pull chunks of rock from the ground.

Abrasion

Process where rocks embedded in the glacier scrape against bedrock.

Remote Sensing

Using satellites to monitor ice sheet extent, thickness, and velocity.

Greenland Ice Sheet

Rapidly losing ice, significantly contributing to sea level rise.

Antarctic Ice Sheet

Divided into East (larger, more stable) and West (smaller, more vulnerable) sections.