Anyone who has visited Zermatt and travelled up to Rotenboden or Gornergrat on the Gornergratbahn will have seen the Gorner Glacier, even if they didn’t know it’s name. It’s the second largest glacial mass in the European Alps after the mighty Aletsch Glacier.
It stretches for nearly nine miles, firstly as the combination of the Gorner and Grenz glaciers that flow either side of Monte Rosa; and progressively it is joined by a number of tributary glaciers. I’ve written about this Glacier before, click here to visit an earlier post.
We have an idealistic view of glaciers as ribbons of white – and indeed in winter this is what they may look like, but in summer the reality is very different. As the surface snow melts, the bare ice of the glacier is revealed, riven by giant slits or crevasses. These occur principally where the ice is subjected to uneven stress: where there is a change of direction, and most commonly when there is a sudden change in the slope of the underlying terrain.
The warmth of a summer’s day melts the surface of the ice: some of this melt water flows across the surface of the ice creating channels, which become deeper with time. Some of the melt water funnels deep into the interior of the glacier. Research into the Gorner Glacier has found vertical shafts as much as 65 ft deep into vast caves deep within the ice. Click here to see the article. A few weeks ago I posted a close-up image of the glacier showing a small glacial lake and giant holes punched in the surface of the ice. click here to view.
When you look closely at the surface of the Gorner Glacier it is possible to identify a recurring pattern of surface markings.
This final image shows a number of features. Firstly the deep channels burrowed into the ice by melt water. In places there are likely to be deep sink holes, obvious ones in the image can be seen at the right edge. You can see the stratification in the ice walls of these scooped out hollows – each layer like a tree’s annular rings – each stratum represents a significant snowfall. The surface of the glacier is pock-marked by ice that has been through countless freeze/melt cycles. You will find often that each pock mark contains a rock fragment that has concentrated the warmth of the sun and accelerated local melting. Finally the snow is yellowed in places – a combination of wind-blown local dust and also snowfall that was coloured yellow when it fell because it was carrying Saharan dust.
Finally, I must mention Glacial retreat. I first saw this glacier over fifty years ago and somewhere, but I can’t find them currently, I have the postcards from that visit. There has been clearly visible fundamental retreat of this glacier. Perhaps the most obvious is the drop in width and height. The route to the Monte Rosa hut even twenty-five years ago across the glacier was straightforward: a path from Rotenboden led down to the edge of the glacier. Now the surface level of the glacier has dropped considerably and the final descent to the glacier is only possible with the use of ladders.