GEG 3107 Lecture Notes - Lecture 3: Cirque Glacier, West Antarctica, Ice Shelf
Document Summary
By area: 85-86% of the world"s glaciers are found in antarctica. Ice sheets (antarctica and greenland) and ice caps are unconstrained by topography. Ice dome: roughly symmetrical, deforms slowly, can be over 3000m thick. Colder ice deforms more slowly than warmer ice. Domes are very good for ice cores, due to low deformation. Ice streams move adjacent to other ice, while outlet glaciers move adjacent to rock/ice free land or into water. Piedmont lobe: flow through a narrow area, then spread out. Sea ice ice shelf (mostly in arctic): Formed by snow accumulation on sea ice, and by basal (under the ice) growth. Glaciers grow by gaining more mass than is lost through ablation. Snow (density = 50-200 kg/m3) firn (400-830 kg/m3) glacial ice (830-910 kg/m3) Restructuring by wind, movement and deformation of crystals etc. are also important factors in ice formation. All require energy input (from the atmosphere or the sun)