ice sheets/shelves

• the Greenland ice sheet is melting through evaporation due to rising air temperatures
• the Antarctic ice sheet is losing mass through iceberg calving and the melting of ice sheets due to rising ocean temperatures
• Ice shelves do not directly relate to sea level rise however they act as a wedge holding back the main glacier and so the loss of them accelerates the melting of glaciers
• Shelves can also act as pins
• MISI is warm water melting\
• Retrograde slopes occur at pins, where the ground slopes away from the sea due to the Isostasy of the glacier, if water begins to flow down the slope, propagating failure occurs and the glacier is eroded at speed
• MICI: failure due to fracturing or cracking of the ice sheet (cliffs and canvasses behind them)
• The keeling curve measures the exponential increase in carbon dioxide levels in the atmosphere since 1958, it shows seasonal oscillations due to the biosphere 'breathing'
• the grounding line of a glacier signifies the point where accumulation and ablation meet