Visible evidence of glacial melting
The Norwegian Glacier Museum & Ulltveit-Moe Center for Climate Science has naturally been interested in glaciers and what is happening to them since its inception in 1991. The trend is that they are melting, but this year one glacier has actually advanced.
Bøyabreen 2016. Photo: Pål Gran Kielland.
Among other things, we carry out front position measurements on some glaciers, but quantifying the changes does not always make sense to everyone. Now that the melting of the glaciers makes some of the measurements difficult to perform, fortunately photography is a good tool for following the development. We are particularly keeping an eye on Bøyabreen and Store Supphellebreen in Fjærland, which we carried out measurements on up until 2014. Already in 2014, a "black hole" was reported in the glacier tongue of Bøyabreen. This hole is also clearly visible this year and is a clear sign that the glacier is thinning.
Bøyabreen 1997 (photo: Stefan Winkler) and 2016 (photo: Pål Gran Kielland).
By comparing photos of Bøyabreen in 1997, when it was at its largest in modern times, and today's condition, we see that the regenerated glacier in the valley floor has now almost completely melted away. More and more solid rock is becoming visible. The changes have been significant since the late 1990s. When we measured the glacier from 2003 to 2014, we saw that the glacier retreated 160 meters in total.
Store Supphellebreen 1997 (photo: Stefan Winkler) and 2016 (photo: Pål Gran Kielland).
Looking at Store Supphellebreen, it is also clear that the regenerated part of the glacier is shrinking. We measured the glacier from 1992 to 2014 and recorded a total melt of about 70 meters.
Stone block in 1899 (photo: John Bernhard Rekstad) and 2016 (photo: Pål Gran Kielland).
Very recently, we actually discovered a large boulder that was used as a permanent marker when front position measurements began in 1899. It was the state geologist John Bernhard Rekstad (1852-1934) who created this marker to measure the distance to the glacier. At that time, he measured 77 meters to the glacier edge. Today, we find the boulder just over 400 meters from the glacier, which means a second melting of over 300 meters since 1899. In the picture from 1899, Rekstad himself is standing next to the boulder, while the director of operations at the Norwegian Glacier Museum, Svein Arne Bøyum, is depicted in the new picture.
Store Supphellebreen (Flatbreen) in 1906 (photo: Monchton) and 2012 (photo: Pål Gran Kielland).
Higher up in the mountains we also see changes. Just over 100 years ago, Store Supphellebreen, popularly known as Flatbreen, was located, blocking and plowing up the large end moraine near Flatbrehytta. Now, in retrospect, development has gone the wrong way with the glacier retreating. To put it simply, the air is simply going out of the balloon.
Front position measurements
This year we have measured changes in the front position of Haugabreen in Jølster and Vetle Supphellebreen in Fjærland. The measurements show that Haugabreen has melted 15 meters back in 2016. Since we started measuring the glacier in 2013, it has retreated a total of 35 meters.
Haugabreen glacier 2016 (photo: Pål Gran Kielland).
Vetle Supphellebreen, on the other hand, has advanced 16 meters in the past year. The current trend is that glaciers are melting back due to the climate becoming warmer. The accumulation of snow is usually very large every winter, but clearly not large enough to prevent glaciers from melting back over time. The advance of Vetle Supphellebreen of 16 meters this year is therefore interesting. We do not have any other measurements of the glacier than these front position measurements to refer to, but if we look at the Meteorological Institute's weather and climate data, the measuring station at the Norwegian Glacier Museum has overall registered precipitation amounts above normal in the period 2011-2015. Large amounts of snow may be part of the explanation for the glacier's advance in the past year. Together with factors such as temperature, latitude, altitude, terrain (steepness and solar radiation) and proximity to the sea (maritime), precipitation is part of a complex interaction that leads to the formation and change of glaciers. Since 2011, when we started measuring the glacier, it has advanced a total of 2 meters.
At the front of Vetle Supphellebreen 2016 (photo: Pål Gran Kielland).