1.6
High tech exploration of water flow inside glaciers
Did you know?
There are rivers and waterfalls in glaciers and on ice sheets
There are large caves inside glaciers
As some glaciers are like Swiss cheese with caves and tunnels, the collapse of glaciers might be faster than we expect
There is also life inside glaciers See story 3.1
Decomposition in bottles
Meltwater is caused by the surface of the glacier melting due to sunlight and high temperatures, particularly during long polar days in the summer. However, these days are becoming hotter and are happening more frequently due to climate change. Meltwater causes streams on the surface of glaciers, which can quickly turn into rivers and channels. The surface meltwater can even penetrate below and through the glacier. These subglacial meltwater channels and waterfalls can be complicated and extensive with the longest subglacial channels recorded to be up to 100 km long.
How does this happen?
1
Surface ice on the glacier melts by the heat from the sun
2
The surface meltwater moves towards crevasses (cracks due to glacier movement) in the glacier. This causes a sink for the streams.
3
The crevasses get deeper and the streams get bigger.
4
With more meltwater passing through the streams, the water erodes (wears away) the channels more, causing them to become larger and longer and the volume of the glacier ice to decrease.
5
Meandering channel systems are formed and sometimes even waterfalls within the glacier.
6
Where there are caves at the end point of glaciers, this part of the glacier can collapse suddenly.
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