The Icebound/Driftwood expedition to Kongsøya
Top image: S/Y Aleiga in front of Hansbreen with WIenertinden in the background and Fannytoppen to the right. Photo: Anne Hormes.
Six scientists set sail for Kongsøya in August. Read the blog from their expedition to eastern and southwestern Svalbard in their quest to unravel the secrets of deglaciation, uplift and sea ice drift.
25 September 2014
Text: Anne Hormes, Hans Linderholm, Toby Koffman and William Philipps
An international team of six scientists set out in August with the expedition sailing boat Aleiga to Kongsøya. No geologist has visited Kongsøya for the last 22 years and the last ones saw more polar bears on that island than reindeers.
Our skipper Niklas Gerhardson was very disappointed that he didn’t see a lot of wildlife on this easternmost island, but we quite enjoyed that the only ´polar bear´ that we thought we had seen, was in fact a white quartzite boulder.
Our journey started with the sail trip from Longyearbyen to Kongsøya. Out of Isfjorden and along the western Spitsbergen coast we needed aid from the engine. But as soon as we rounded Sørkapp we got perfect wind conditions and started sailing. It was a fantastic feeling to sail over the Barents Sea. It took us only a bit more than 2 days and during this time we prepared our fieldwork and looked out for icebergs and driftwood during night watches.
When we anchored in Vrakbukta in western Kongsøya we were greeted by some curious seals and could finally go on land. Kongsøya has a relatively flat relief with wide marine terraces up to 100 m and a few plateau mountains that reach a bit more than 300 m. Hans and his dendro team worked on the beaches, while team Icebound explored up on the mountains.
The aim of the Icebound project is to unravel the configuration and ice stream directions of the Svalbard Barents Sea ice sheet that covered the complete Svalbard archipelago and the Barents Sea between 32000 and 11000 years ago.
We found evidence of glaciation in form of polished and striated basalt bedrock and very few erratic boulders. The rock types of these glacially transported boulders will be compared to a comprehensive bedrock collection from different regions in Svalbard in order to reconstruct the ice flow directions during the glaciation that brought the boulders to Kongsøya.
We want to find out if the ice came from Nordaustlandet or if the island was covered under a local ice divide. We plan to determine the timing of deglaciation by measuring what can be thought of as an invisible chemical suntan. When rock surfaces become ice free, exposure to high-energy particles produced by cosmic rays leads to the creation of several rare isotopes that build up as long the rock is exposed to the sky. We will spend months in the laboratory to measure the concentrations of accumulated isotopes and use these as a clock to determine when the ice sheet receded from Kongsøya.
The aim of the driftwood project is to compare driftwood (amount, species and origin) across Svalbard to infer past ocean circulation and sea-ice patterns back in time (e.g. last couple of millennia), as well as attempt to date raised beaches at selected locations.
On Kongsøya, samples were taken from raised beaches on Kapp Andreassen and Tømmerneset. Thin disks are taken from the driftwood remains, and subsequently we will determine the species (e.g. Larix, Picea or Pinus), and measure the annual tree rings. Using dendrochronological techniques, we hope to both date the samples as well as determine from where they came.
The second aim of the trip was Sørkapp, but the ocean’s swell made it impossible to land here. Therefore, we decided to sail to Hornsund as Toby and Anne already have been working here the last two spring seasons and to complement our data series.
In Hornsund and Dunderbukta on the west coast of Spitsbergen, we were able to sample elevation transects of mountains that will give us an insight of the thinning of ice streams at the end of the last glaciation and its timing.
The rapid collapse of present ice streams in Greenland and Antarctica has led to increased concern of climate change impact on our big ice sheets. We hope to contribute to more knowledge with our elevation transects that will be dated with a broad band of different isotopes.
In addition to driftwood lying exposed on the present day beaches, we sampled wood buried in sediments or recently exposed due to the melting of perennial snow pack on Kongsøya, Hornsund and Dunderbukta. This will hopefully yield samples of old dates. Due to the human activities around Svalbard (hunting and mining) a large quantity of old driftwood has been removed for building purposes or fuel.
Thus, we expect that most of the material will be from the last century or so. Still, since we have sampled several sites affected by different ocean currents, we hope to be able to infer changes in these currents and sea-ice concentrations over time using the driftwood data.
In Bellsund we sampled a moraine transect in front of Scottbreen that is thought to represent only the Little Ice Age, but our field observations suggest also some older moraines that might be have been deposited a couple of thousand years earlier due to their weathered appearance.
Despite many fine marine terraces in Bellsund, we could not find any driftwood material above the current beach level. Likely the activities in and around Calypsobyen removed most of the material. However, we found plenty of driftwood on close to the sea level when sampling below Scottbreen and Recherchebreen.
We returned to Longyearbyen after a couple of intense working days in Bellsund. This time we could sail only for a couple of hours with the wind into our faces.
The day after we returned to the civilization and we undertook the task to pack our samples and send these to Gothenburg and New York State University at Buffalo. We collected nearly 400 driftwood samples and about 150 kg of geological samples, but that is another story.
What about polar bears then? We thought that we would meet lots of them and were concerned that a meeting with the king of Kongsøya could have seriously disturbed our working objectives.
However, in mid-August the sea ice edge was located north of Kongsøya and that was our good luck. We didn’t see a single living polar bear on Kongsøya, neither on the rest of the trip. However, when we arrived in Longyearbyen a polar bear at Hiorthhamn was having a happy time.
The Icebound team consisted of expedition leader Anne Hormes (University Centre in Svalbard and University in Gothenburg), Toby Koffman (Lamont-Doherty Earth Observatory) and William Philipps (New York State University at Buffalo).
The driftwood team consisted of Hans Linderholm, Mauricio Fuentes (both University of Gothenburg), and Björn Gunnarson (Stockholm University). We had two gifted skippers with us: the owner of the boat Niklas Gerhardson (Spitsbergen Sailing) and Anders Aulie (Spitsbergen Sailing).