How do glaciers shape the landscape? Glaciers
are frozen rivers of ice, which have immense
power. Glaciers are so powerful, they can
carve huge chunks out of mountains as they
flow downhill. This makes them one of the
most powerful natural tools on our planet.
Glaciers are sometimes called nature's bulldozer.
Just like a bulldozer, glaciers shape the
land in three ways. Firstly, glaciers pick
up material. We call this erosion. Water flowing
along the bottom of the glacier seeps down
into the rock below.When it freezes, it opens
up the cracks in the rock. This is known as
freeze-thaw weathering. Then, as the glacier
flows downhill, pieces of rock come loose,
and the glacier pulls them along with it.
We call this plucking. Ouch! These rocks and
stones scrape along the glacier bed like sandpaper,
taking more rocks and stones along for the
ride. This is called abrasion. Secondly, the
glacier transports this erode material as
it flows downhill. Some of it is hidden inside
or at the base of the glacier, where it can't
be seen, but sometimes it is transported on
the top of the glacier. This is why glaciers
often look dirty. As the glacier flows down
a mountain, it gets warmer and starts to melt.
Just like a snowman, anything which cannot
melt is left behind. As the glacier melts,
the rocks and stones fall to the ground. We
call this deposition. By now, this material
is a tasty mixture of rocks, stones, sand,
and clay, known as glacial till. The melted
ice turns into melt water and flows downhill
to join a river or lake. Today glaciers only
exist in the coldest parts of our planet.
But during the last ice age, glaciers existed
in the UK too. Although the ice has melted,
they have left behind some awesome scenery.
As our planet warms up, many of our amazing
glaciers are melting fast. So grab your walking
boots, and head to your nearest glacier, while
there's still time to see nature's bulldozer
in action.
