What cause a decrease in glaciers?
1 Answer
Glaciers retreat if they are losing mass.
Explanation:
Glaciers gain material through snow fall. This is called accumulation.
They also lose material through melting and sublimation. This is called ablation.
The difference between accumulation and ablation is called the mass balance.
If accumulation and ablation are the same then the glacier is in equilibrium.
If accumulation is greater than ablation then the glacier will advance until it reaches equilibrium.
If accumulation is less than ablation then the glacier will retreat. It will retreat until it is either in balance or disappears completely.
Nearly all glaciers are currently in retreat. The reason for this being climate change. Higher temperatures increases melting. One problem which often affects the Alps is if a high pressure block stays over the mountains for weeks in the Winter months it prevents cloud formation and there is no snowfall.
