The system theory

• What is a glacier?

  An ice mass or sheet at the plain of the Earth
• What defines an open system?

  A system in which energy and materials move across its boundaries
• What percentage of the Earth is currently covered in glaciers?

  10%
• How much of the Earth was covered in ice during the Pleistocene period?

  1/3
• Where do glaciers typically form?

  High latitudes like Antarctica and high altitudes like the Himalayas
• How do glaciers form?

  When annual solar radiation cannot melt the annual snowfall and precipitation is mainly snow
• What geographical systems do glaciers interact with?

  Atmosphere, oceans, and rivers
• What are the inputs in the glacier system?

  Precipitation, rock debris, kinetic energy, thermal energy, and gravity
• What are the throughputs in the glacier system?

  Snow, meltwater, rock debris, kinetic energy, and thermal energy
• What are the outputs in the glacier system?

  Water, water vapor, ice, rock debris, and energy
• What are the stores in the glacier system?

  Ice, meltwater, rock debris, and gravitational potential in rocks
• What is calving in relation to glaciers?


  The breaking away of blocks of ice from a glacier into water
• What does the term "aeolian" refer to?

  The action of wind
• How is a system defined in the context of glaciers?

  A set of interrelated objects comprising links and stores
• How do glaciers change over time?

  • Seconds/minutes: Weathering and erosion, ablation and accumulation
  • Millennia: Glacial and interglacial periods; Milankovitch cycles (eccentricity, axial precession, sunspots); global warming