Mass balance and glaciers as systems

• What is glacier mass balance?

  The annual difference between the amount of ice and snow accumulation and the amount of ice and snow ablation
• What is glacier accumulation?

  When there is a net gain of ice to a glacier during a year
• What is glacier ablation?

  When there is a net loss of ice to a glacier during a year
• What happens when there is a positive glacial mass balance?

  The glacier's mass increases and it advances
• What happens when there is a negative glacial mass balance?

  The glacier's mass decreases and it retreats
• What are the three main inputs in glacial mass balance?

  Precipitation in the form of snowfall, avalanches from mountainsides, and wind deposition
• What are the three main outputs in glacial mass balance?

  Water which results from melting, calving of chunks of ice, and the processes of evaporation and sublimation