7They’ve formed over hundreds of years

Forming a glacier is a painfully slow process that takes place over a period of hundreds of years. 

It starts with build up of snow that doesn’t melt and, with further snowfall, the weight of the accumulation begins to compress the snow, packing it down forcefully onto itself. The pressure eventually turns the snow into very dense ice where practically all of the air bubbles have been squeezed out.

RELATED ARTICLESMORE FROM AUTHOR