Please be careful and do not walk close by the water running at the glacier - it can be lethal. You will notice the danger zone as an area with no vegetation where calving chunks of ice from the glacier and Jökulhlaup (glacial outburst flood) occurs occasionally.
The Russell Glacier, located in central-western Greenland, flows from the Greenlandic Ice Sheet at a rate of about 25 m per year. It is a ‘land-terminating’ glacier, meaning that it mainly loses mass through melting in contrast to the calving of icebergs into the ocean. The Russell Glacier area provides an excellent opportunity to view typical glacial erosional and geomorphologic features. The picture and this video http://www.youtube.com/watch?v=tLgaG4qmL1g shows Russel Glacier.
Catchment area Streams from the Russell glacier form the Akuliarusiarsuup Kuua river, which flows west-south-west towards the settlement Kangerlussuaq. On the way it joins the Qinnguata Kuussua river before reaching Kangerlussuaq Fjord. Passing Kangerlussuaq the river is known as Watson River. The catchment area of the Watson River is estimated to be 30 km wide and extend 300 km inland to the ridge of the ice sheet at an altitude of approximately 2.500 m. This gives a catchment area of approximately 9,000 km2. Scientists have shown there to be an accelerating loss of mass around the exterior of the Greenlandic Ice Sheet resulting in an increased meltwater production. July 2012 this lead to record high melting and destruction of the Watson River Bridge at Kangerlussuaq: https://www.youtube.com/watch?v=v5h3AdiJT8A.
Albedo Melting is accelerated by a decrease in albedo (light reflectivity) which causes more sunlight to be absorbed by the surface. Decrease in albedo is caused by increased amounts of dust coating the ice as well as the formation of surface melt ponds with their dark blue colors. Erosion While the Greenlandic Ice Sheet moves across the surface of the bedrock with the pressure of up to 3,300 m of ice and rocks working as sandpaper, the bedrock is gradually is eroded. The Ice Sheet erodes an average of about 2.3 mm of subglacial bedrock every year. Scientists have estimated this by measuring sediment flux, derived from meltwaters emerging from glaciers in west Greenland.
Sediment transport Eroded material is transported by the ice and by meltwater to the glacier front. The smaller particles (silt and clay) are transported by the meltwater to reach a river and eventually the Fjord of Kangerlussuaq.
Moraines The bigger particles accumulate in the ice or they are pushed at the interface between ice and bedrock to reach the terminus of the glacier, where it is deposited in large amounts. The pile of sediment a glacier pushes in front of it is called a moraine. The longer the terminus of the glacier stays in one place, the more material accumulate in the moraine. Moraines can be found along the path of most retreating glaciers, including the Russell Glacier. The Picture shows the moraine in front of the Russell Glacier.
To claim this cache you have to physically visit the site and send me an e-mail with answers to the following questions. As usual, do not post your answers in the log! No need to wait for a reply from me, you can log the find right after you have sent the mail. If there are any problems with your answers I will contact you.
EarthCache questions
1. Analyze the rock surface at the coordinate. How was it formed?
2. Estimate which direction the ice approximately has been moving during the previous ice age.
3. Calculate the amount of sediment (in m3) released every year from the Watson River catchment area.
4. At other locations close by the coordinate you will not find a similar smooth surface. What is the explanation?
5. This is optional. Take a photo at the coordinate facing the glacier including the terminus and the moraine in front of it. In order to see the difference of the glacier over time.