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Kangerlussuaq Field School 2012. By Group Four: Sydney Barnes, Aggu Broberg , Malene Olesen , Nivi Knudsen. Is the Greenlandic Ice Sheet Melting?. Group Results. The bamboo sticks on the ice sheet Moraines and lakes on the ice sheet Watson River Measurements Sprintt Data.
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Kangerlussuaq Field School 2012 By Group Four: Sydney Barnes, AgguBroberg, MaleneOlesen, Nivi Knudsen
Group Results • The bamboo sticks on the ice sheet • Moraines and lakes on the ice sheet • Watson River Measurements • Sprintt Data
Bamboo sticks on the Ice Sheet (Point 660) AsaRennermalm – Geographer from Rutgers University Asa drills holes in the ice and places bamboo sticks in them, and by periodically checking the sticks, she can measure how much the ice melts at point 660 over a given period of time.
Moraines A moraine is an accumulation of soil, rocks, and other glacial debris. They are formed where the glaciers meet the land. They are easily identified because they appear out of place on the landscape.
The Moraine that Asa showed us You used to be able to see the ice sheet from the road, but it has receded behind the moraine. This shows that the glaciers are slowly receding over the years. If you look at Google Earth, you can also see that the meltwater lakes on the other side of the moraine have increased in size.
Meltwater Lakes on the ice Images from Google maps show an increase in the number of meltwater lakes on the Greenlandic ice sheets. Table 1. Data from SPRINTT
Watson River Sediment Discharge Measurements Our experiment was designed to find the amount of Sediment (in kg) that flows out of the Watson River a day. Group 4’s experiment failed because our side of the river had much rougher water that covered our indicators. However we were able to take the data from group 5.
Watson River (Cont.) We found that the water travels 102 meters in 14.3 seconds over a 40 m2 cross section. And it had a velocity of 7.13 m3/s. So, if you multiply the velocity by the cross section you get the discharge of the river, which is 285 m3/s. We were told that there is 2 kg/m3 of sediment in Watson River, therefore there is 570.62 kg of sediment flowing out every second. If you multiply that number by the number of seconds in a year (excluding the seconds that the river should be frozen and therefore not discharging sediment, 86400 seconds) You find that there is roughly 49,301,568 kg of sediment discharged by Watson River every year.
Sprintt Data • This data showed a decrease of 4% in total area of the Greenland ice sheet. • Mass balance = accumulation – ablation • Jakobshavn Glacier shrunk 8 miles and moved 113 feet per day in the last 5 years. Average speed of moving glaciers in the world is 1 foot. Table 2. Data from SPRINTT
What will happen if the ice sheet melts? the ocean will rise up to 7 meters and some of the cities/countries will be Covered in ocean. If both Greenland and Antarctica melts down the water Will rise up to 80 meters. Greenland will rise and when the ice sheet melts Greenland will experience earthquakes when the ice sheet is one.
So, is it melting? Although from our data it would appear that you could say the Greenland ice sheet is melting. However this cannot be said for sure because all the data we have is only outflow. You would need inflow data as well to say for sure whether or not the ice sheet is melting.
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Any Questions? Photo Credit:DanaCucci
