Today is our last full sampling day on Disko Island. We get up early to make the most of it, fill our bags with food, water, and sampling equipment, and head off on the steep, scrambly trek to Lyngmark Glacier. As we advance up the contour lines, the sky becomes less and less welcoming – our big blue sunny skies of the past week have well and truly gone. We are determined to get to Lyngmark – a few hours is all we need to significantly add to our sample haul, and after passing a few other hikers and scientists along the way we eventually make it to the small hut near the summit. However, the sky has descended giving us a visibility of less than 10 m, and we are forced to consider the possibility of turning back – 10 m visibility over ground will turn into a whiteout at the glacier itself, and no matter how much we want to get there, it would be foolish to compromise our safety. We have a long lunch and hunker down in the hope the skies might clear – the last thing we want to do is head back down to Arctic Station, only to see the sun shining on our return.
The final decision comes when we bump into a scientist from the University of Copenhagen who has been working on Lyngmark Glacier over summer. She and her team are on their way back down the mountain, and she advises us not to go all the way to the glacier itself as it’s too unsafe. Whilst not a great surprise, it is disheartening that our last sample day, finally with all our proper equipment, has to be abandoned due to poor weather. Having had such clear skies all week, the timing could not be worse. As if to further convince us, it starts to snow, and it’s time to leave Lyngmarkfjeld mountain.
As we descend through the snow, cloud, and fog, we cross through the snowline and the snow turns into rain. The bad weather persists until we reach the bottom of Lyngmarksfjeld, and it finally stops raining. From here we split into two – Mark and Casey head back to Arctic Station to start weighing and cataloging all our samples collected so far, whilst Sami and I branch off to explore the geological contact between the Precambrian basement gneiss (approx. 1700 million years old) and the overlying, younger basalts (70 million years old). Along this contact is a thin unit of a deposit known as a saprolite, which represents deep weathering of the bedrock surface. We sample several exposures of these saprolites, before calling it a day and heading back to Arctic Station.