Some of the ice in the Juvfonne glacier in Jotunheimen National Park in central Norway has been dated to be 7600 years old, currently the oldest dated ice on mainland Norway.
“We were a little surprised to find that the ice from Juvfonne was that old,” says Rune Strand Ødegård, an associate professor at NTNU’s Department of Manufacturing and Civil Engineering in Gjøvik.
About 10000 years ago, the ice in this area melted as the climate warmed, which was at its warmest between 7000-95000 years ago. The new results from Juvfonne suggest it might be possible to find ice from the last ice age in the high-mountain areas of southern Norway.
Juvfonne and the oldest ice
- Juvfonne is found at the base of Galdhøpiggen
- A number of studies are being done on and around Juvfonn as part of "Klimapark 2469"
- Klimapark 2469 is an outdoor experience that partly focuses on climate history, hunting and gathering.
“There is likely even older ice, as this 7600 year old ice was found at an elevation of 1850 meters. The old ice found in Juvfonne is dated to the warm period after the last ice age, so it’s really exciting to have found ice that survived the last warm period,” Ødegård said.
Ice samples to be analysed in Switzerland
Juvfonne is a small ice patch at the base of Galdhøpiggen in Jotunheimen. A tunnel has been chiseled into the ice at the base of the field. Samples were taken from this tunnel and sent to the Paul Scherrer Institute in Switzerland for carbon dating. The results came back that the ice was 7600 years old.
So far, the ice has only been dated. No other analysis has been done, as the age of the ice was unknown.
“The results mean that organic material could have been frozen into the ice field for 7000 years, which will lead to new knowledge. However, we haven’t done a detailed analysis for organic material yet,” Ødegård said.
The results will hopefully lead to the possibility of finding even older ice and organic material preserved under the glaciers in Jotunheimen.
The most well-known archaeological find from Jotunheimen’s glaciers is Norway’s oldest shoe, which is 3500 years old.
Researchers have been measuring the age, internal structure, mass balance and climate sensitivity of the ice in Juvfonne since 2010. Bad winters seem to have been eating away at the snow and ice depths, although the studies show that large winter storms still help the ice patches grow.
“Six years of measurements gives us too little data to say anything about long-term effects, but the development is worrying,” Ødegård said.
Ødegård worked with researchers at the University of Bergen, the University of Oslo, the Norwegian Meteorological Institute, NVE and the Paul Scherrer Institute on the research conducted on Juvfonne.
Reference: Ødegård, Rune Strand; Nesje, Atle; Isaksen, Ketil; Andreassen, Liss Marie; Eiken, Trond; Margit, Schwikowski; Uglietti, Chiara. (2017) Climate change threatens archaeologically significant ice patches: insights into their age, internal structure, mass balance and climate sensitivity. The Cryosphere. vol. 11.