| Term: | Moulin |
| Definition: |
A nearly vertical channel in ice that is formed by flowing water; usually found after a relatively flat section of glacier in a region of transverse crevasses; also called a pothole. NSIDCCryosphere
A deep shaft, nearly vertical and of roughly circular cross section, formed when surface meltwater enlarges a crack in the ice by transferring kinetic and thermal energy to its walls. Moulins connect to the englacial drainage network, facilitating transfer of surface meltwater to the bed. The meltwater resulting from enlargement of the moulin is an instance of internal ablation. Moulins may play a significant role in supplying lubricant to the bed. The word is French for mill, referring to the swirling motion of the water as it descends the shaft. IHPGlacierMassBalance (from the French) A water-worn pothole formed where a surface meltstream exploits a weakness in the ice. Many moulins are cylindrical, several metres across, and extend down to the glacier bed, often in a series of steps. Swisseduc A narrow, tubular chute or crevasse through which water enters a glacier from the surface. Occasionally, the lower end of a moulin may be exposed in the face of a glacier or at the edge of a stagnant block of ice. (glacier mill) GCW |