Matt Nolan and McCall Glacier on the BBC
The upper cirque of McCall Glacier used to spill through this notch in the rock and connect with cirque below, not more than 30 years ago.
Click the image to open an interactive full screen panorama!
Panorama by Dr. Matt Nolan, University of Alaska – Fairbanks, Alaska 360
Matt Nolan’s long journey to the Arctic National Wildlife Refuge has been covered by the BBC. The glacier you see above, McCall Glacier, has been heavily studied for half a century now, and gives a lot of clues about our changing environment….
The main scientific objective has always been to determine the glacier’s mass balance – whether it is gaining or losing ice over time, whether the accumulating snowfall during the winter is more or less than the summertime melting.
The methodology is surprisingly straightforward – “rude and crude,” as Matt Nolan labels it.
“You take a steam drill, bore a hole between three and nine metres in depth, and put in a stake – in fact we sometimes use pieces of electrical conduit.
“You measure how much of the stake is exposed when you put it in, then you go back at a later time and see whether more or less is now exposed.”
And you do it all over the glacier, to take account of the different conditions at various altitudes, and combine the readings to derive a trend for the entire ice body.
In 1998, Professor Echelmeyer showed that the McCall had been shrinking ever since the first measurements were taken in 1957, and that the rate of loss had increased.
The glacier thinned each year between 1972 and 1993 by an average of 33cm. Subsequently, the rate nearly doubled.
