Friday 7 September 2018

Exploring a retreating glacier

Not long after we arrived, we hiked up the valley to Twin Glacier. Along the way we were introduced to some of the past research projects that have been conducted at Alex Fiord including ‘the farm’ where vegetables were grown under different light and temperature regimes to determine the best growing conditions where there is 24-hour light. Apparently, the farm was so successful that vegetables were being flown down to Resolute to be used by the PCSP kitchen.
Hiking up the valley to Twin Glacier with Alexandra Fiord, Sphynx Is.,
Buchanan Bay and Bache Peninsula in the background.
Signs of Twin Glacier retreating were everywhere. In the 1980s the two halves of Twin Glacier met but now they are far apart. We stopped for lunch at a large boulder that marked the terminus of the glacier in the 1950s - it is now a half hour walk to the glacier from the boulder. Each year a stake has been placed to mark the terminus of the glacier for that year - they are about 10-20m apart. There is a wide band of lighter coloured rock on the mountain sides above the glacier – the transition from dark to light rock marks where the glacier used to be. 
The hike to Twin Glacier. In the 1980s, the two arms of the glacier
met at the prominent ridge in the centre. The rocky hill in the
middle is no longer a Nunataq.
The lunch rock marked the terminus of the glacier in the 1950s, now
it is a half hour walk to the glacier (seen in the distance) from
the lunch rock. The rock is used to take repeat photographs
each year to visually follow the glacial retreat.
Band of lighter coloured rock around the west arm of Twin Glacier
(centre) marking the extent of the glacier in the 1950s. The east arm
(left) and west arm were joined in the 1980s but now there is a large
expanse of rock between them which is slowly being recolonized
with poppies, willow and other early succession plants.
Photo taken from East Ridge.

The Twin Glacier is a special type of glacier in that it is frozen to the ground and, as it advanced, the plants it covered have remained intact. Now that the glacier is retreating, these plants, that are 1000s of years old, are being exposed. The leaves and sometimes even flowers and fruits are perfectly preserved. These ancient plants can be carbon dated and are helping to form a picture of past warm and cold periods in this region of the Arctic.
Ancient plant re-emerging from under the retreating glacier.
This is a mountain avens plant (Dryas integrifolia) that was
alive thousands of years ago.

We hiked up along the side of the west arm of the glacier and then up onto the glacier. It was awesome to stand underneath the sheer ~100ft side of the glacier. Once on the glacier, I really appreciate the immenseness of the glacier as it stretched far back towards the Prince of Wales Icecap. 
The views back down the valley from the glacier were spectacular.
West arm of Twin Glacier with Alexandra Fiord and Buchanan
Bay in the background. The glacier dwarfs the person walking
along the side of the glacier.
Walking on Twin Glacier the immenseness of the glacier is appreciated
Walking down off Twin Glacier.

The glacier is dotted with holes in the surface that are all about
6 inches in diameter and perfectly round.
Algae have created
their own little circular microcosm in the glacier.
 

1 comment:

  1. That is fascinating - I knew glaciers are large but didn't appreciate just how big! It is well known that snow preserves things but to me, a novice in these matters, it is amazing that the flowers & fruit weren't crushed by weight of snow.

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