This photo is from our flight onto the ice sheet. The margins of the ice sheet are heavily crevassed. The size of the Greenland Ice Sheet is jaw-dropping; the ice sheet spreads out in all directions. I knew the ice sheet was big, but it's a completely different thing to see it in front of you.
Several of our GPS stations were installed near a "supraglacial lake" (shown above). The prefix "supra-" means above, so the term refers to a lake formed on the top of the ice sheet. These lakes are sourced by glacier melt and form because there is no easy way for the water to drain from the top of the ice sheet to the bottom of the ice sheet. Some of these lakes periodically drain through the formation of a moulin (as I talked about in a previous post) and other lakes never drain. When these lakes drain, they drain a significant quantity of water to the ice sheet base, which can lubricate the rock-ice interface and potentially cause the ice to move faster.
On our flight two days ago we took a detour to the terminus of Jakobshavn Glacier. This photo shows the calving face of the glacier. Ice is constantly breaking off the glacier in small and big chunks, forming icebergs like the one shown below.
That's one big iceberg! Many believe that Jakobshavn produced the iceberg that sunk the Titanic.
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