Glacial Impact on Lithosphere
Just as they react to the climate around them, glaciers change the landscape they cover– the weight and pressure of many feet of ice not only compact the ice itself but have an impact on the ground below. The sheer weight of the ice pushes the ground down. The vast Antarctice ice sheet, more than 3000 meters deep, has depressed the Antarctic continent more than 2000 meters below sea level.

Glaciers also transform the land as they move. They scour and reshape valleys, such as the sheer-walled valleys of Yosemite National Park. Glaciers scrape glacial potholes where lakes may form after the glacier disappears. They push the dirt and rocks ahead of them, creating ridges—moraines—at their leading edge.

As they retreat, those moraines are left behind and are called terminal moraines. Lateral moraines are left where two glaciers once came together, or a single glacier has pushed debris off to the side. Glaciers may also carve fjords (deep, water filled U-shaped valleys) as evidence of their passage.

Next: Types of Glaciers