In travelling past the great ice divide upon which Kohnen Station sits, we have moved into a new area of ice drainage, and a new local climate. We have entered the domain of the trolls.
Location: ”NUS08-7”, 74º 07’ S, 1º 36’ E, 2700 metres a.s.l.
Weather: Mostly clear, -33 C, wind 13 kts
We are now in the upper reaches of a massive, fast-flowing outlet glacier for the East Antarctic Ice Sheet, Jutulstraumen Glacier – the Jutul’s stream. It is named after Jutulen, a character from the Norwegian folk tales. Jutulen was a troll-like figure who could take on the appearance of a human being and ride his sledge through the skies. He used to live inside a mountain, entering through a huge gate in the mountain face.
Jutulstraumen parallels this, originating behind the mountain ranges, and flowing down to the lowlands through a narrow gateway between the Fimbulheimen mountains. Down there it picks up speed – up to 4 metres per day near the coast – and it is covered with huge crevasses. But up here, the ice flow is slow enough that the ice bends, without breaking, in response to variations in flow speed – thus sparing us any concerns of crevasses.
We are, however, well into the drainage basin of the ice stream, on the downhill side of an ice divide. The ice divides of Antarctica mark boundaries of both ice flow direction and storm tracks. Thus our Site 7 research stop has significantly different snow. Here, the climate is much snowier (although still bone-dry by most standards), and there are occasional weather systems that come in from the ocean out of the northwest (with northerly, up-slope flow, and therefore more precipitation). The snow is firmer, more layered, and easier to dig and core, according to our sampling teams.
We are also in a faster ice flow area, and as a consequence there is greater local topography. This came as a bit of a surprise, since topography is still almost imperceptible if you are just standing and looking at the horizon. But as our skiers glided off for their daily exercise, they noted that the camp disappeared behind them within just a few hundred yards, dipping behind a local rise.
Jutulstraumen flows out to a large ice shelf, the Fimbul Ice Shelf (Fimbulisen), and eventually forms the Trolltunga ice tongue. Every few decades this outflow breaks off as one of the large tabular icebergs Antarctica produces. We will be driving onto Fimbulisen in the next week – more on how it behaves, and looks, then. We’re looking forward to our first new sightings of wildlife (other than ourselves!).
Our work at science site 7 (“NUS08-7”) was completed today, and tomorrow we will tell you more about what we have been up to in Jutulstraumen’s catchment.x