Submitted by Anonymous on Sat, 07/27/2013 - 08:54
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Drumlin Formation in Iceland

I understand what drumlins are and what you're going there to research. My only question is what information can drumlins tell us. You specify glacial movements and earth's systems, but my more specific question would be what about those, and why do they matter?

Sat, 07/27/2013 - 08:56

Anonymous

My names, Logan McRoberts by the way, and I'm in your environmental systems class next year.

Sun, 07/28/2013 - 16:24

Jamie Esler

Logan,Thanks for posting such an authentic and important question. Investigating and learning about how drumlins form beneath glaciers is a huge step towards a greater understanding about how glaciers move and flow. You see, glaciers do not behave in a homogeneous manner from their surface to their bottom (called the bed). The surface of a glacier is quite brittle, and the ice tends to get less brittle and more pseudoplastic (a fluid like solid) towards its bed. This difference causes glaciers to move in different ways. Glaciers generally flow like slow moving viscous substances through a process called internal deformation. However, at the bottom of a glacier, the overlying weight of the ice can actually melt a little bit of ice to form a very thin layer of water between the glacier and the bedrock below. This water can act as a lubricant, causing the glacier to slip or slide much quicker and more abruptly than the typical flow in a process called basal slippage.
Drumlins form at the base of glaciers, and affect which type of movement a particular glacier tends towards. They cause a frictional force on the bed of the glacier, slowing its motion down. This in return can affect how quickly a glacier, say the Antarctic Ice Sheet, makes it way towards the sea. The more we know about how drumlins form, the more we may find out about how glaciers move.
So...why does it matter if we know how glaciers move? It matters quite a bit, actually.
The current warming of the Earth's atmosphere is causing glaciers to melt all across the world at unprecedented rates. Glaciers that are on land, once holding a certain percentage of the hydrosphere in terrestrial/land-based environments, are now losing this water as it flows into the oceans, causing measurable rises in sea level across the entire planet. With many millions of people around the world living in coastal regions, these rises may pose a serious threat to their well-being and/or cultural way of life.
The more we understand how glaciers move (drumlin formation being only one small facet of this large field of science), the better we can predict how quickly receding glaciers will lose their water to the world's oceans. The stronger and more accurate our predictions about this resulting rise in sea level, the better off human societies are at either mitigating or adapting to these changes to Earth's systems.
I look forward to finally having you in class Logan!
Mr. Esler