Two birds with one stone

After a hectic week of logistical challenges, all-day drives across Iceland and a whole lot of lake coring, finally some time to reflect and report on a succesful field trip. In fact, the first for many of us where we managed to accomplish more than originally planned…

Lost in transit

Our trip did not start off on a promising start – upon arrival in Reykavik, we were greeted by howling winds and horizontal rain: typical Iceland weather, but nothing a bunch of seasoned Arctic geologists couldn`t handle. The real challenge was getting our equipment released by customs: some paperwork got lost in transit. Thankfully, things got sorted at the 11th hour so that we could make the most of our time in the field.

Slice of paradise

Wasting no time, we quickly made our way to our fabulous field site, Skeiðvatn: a small lake that looks like a bright blue eye because of the distinct color of the rock flour that is washed in from the up-stream glacier (see our previous blog). We already expected a little slice of paradise, but reality exceed our expectations. Weather conditions had improved dramatically since our arrival: small glaciers with a fresh dusting of snow were reflected in the mirror flat waters, while the surrounding vegetation turned into an autumn blaze of orange-red to scarlet shades. There are worse places to do research.

20180902_105459Skeiðvatn – really really really ridiculously good looking

Kitchen ladder

Needless to say, everybody could not wait to get going the next (bright blue) day. Thankfully, one of the local farmers could be persuaded to transport our field equipment (boats, board engines and a metal coring platform) up to the lake, saving us time (and back problems). A quick boat trip revealed that most of Skeiðvatn is hardly deeper than a regular bath tub. This created additional challenges for extracting the lake`s sediments (our goal), as this involves drilling in a 5m long PVC tube. But nothing a team of scientists can`t solve: we decided to strap a kitchen ladder onto our coring raft to add a bit of height. There are more enjoyable things in life than slamming a 30 kg weight onto a plastic pipe from 2.5 m high, but it got the job done (on day 1). We managed to wrestle no less than 4 m of valuable sediments from depths of Skeiðvatn (without disturbing the monster living there, according to local lore). Which left us time to accomplish more field goals, originally scheduled for another trip (hence the two bird metaphor in the title).

20180903_112614Going up – Science meets home improvement

Spoiled

Next, we drove to our wonderfully comfortable INTERACT field station (Rif), to cut, label, sample and pack our previous sediment cores. We anticipated to use lab space for this dirty (muddy!) work, but the persistently fine weather allowed us to work (and tan) outside. We were spoiled even more as the lovely Kaupfélagið cafe prepared breakfast, lunch and dinner for us during our stay. A fanstastic ending to a succesful field trip.

20180907_141125Packing equipment – a sediment core sandwich 

 

Taking the pulse of natural Arctic climate change using Iceland lake sediments

All field equipment has been assembled, strapped onto pallets and shipped out. In other words, preparations for our upcoming INTERACT TA adventure in northern Iceland are in full swing. High time for a quick introduction of the GLACTIC team and our field plans.

Where and why

It is no secret that the Arctic is one of the most climatically sensitive parts of our planet, heating up twice as fast as the global average. As ice shrivels away and temperatures soar, this dramatic region response to global warming regularly grab headlines. Less well known is the fact that this amplified response is an intrinsinc feature of the region`s climate system, and thus also enhances the impact of natural variations – including cooling phases. There is ample evidence that the Atlantic Arctic was hit by a series of cold spells over the past 10 000 years. The last of these was called “Little Ice Age” for a reason, and severely impacted societies trying to make ends meet in this already harsh region. It was during this time that the Vikings dissapeared from Greenland.

Similar centennial-scale events are bound to happen again. As they modulate the impact of anthropogenic warming, they need to be taken into account in the projections of future climate that underpin policies and adaptation strategies. And that when things get a bit problematic as the fundamental causes of these Arctic North Atlantic climate excursions remain debated. One major challenge complicates things for researchers that try to answer this important question: records of past climate remain sparse and scarce in this remote region – hindering efforts to assess patterns of change in space and time.

GLACTIC will rise to this challenge by providing an important piece to the Arctic North Atlantic`s climate puzzle. For this purpose, we will rely on lake sediment sequences from norhtern Iceland. This area sits near the interface of key components of the regional climate system – the sea-ice margin, the polar front and the meeting of Arctic with Atlantic waters – and therefore sensitively responds to change. The physical, chemical and biological properties of lake sediments capture and record such changes through time, layer by layer over thousands of years. The GLACTIC team wants to unlock this past climate potential by retrieving sediments from the icy depths of lake Skeiðsvatn.

Figure 1. At the frontline of Arctic climate change – northern Iceland and Skeiðsvatn Iceland maps

To extract as much information from our precious lake sediments, as well as approach research questions from multiple angles, GLACTIC brings together climate researchers from different disciplines:

  • Rick Hennekam from the NIOZ Royal Netherlands Institute for Sea Research, an expert in high-resolution sediment core scanning techniques
  • Timothy Lane from John Moores University in Liverpool, who studies landscape development in glacial environments like Greenland and Iceland
  • Kathryn Adamson from Manchester Metropolitan University, who specializes in in the use of sedimentary records as indicators of environmental change
  • Iestyn Barr from Manchester Metropolitan University, who applies remote-sensing techniques to investigate environmental change in mountainous areas
  • Jostein Bakke from the University of Bergen in Norway, who uses glacier-fed lake sediment records to reconstruct past glacier change
  • Willem van der Bilt from the University of Bergen in Norway, who applies new biogeochemical, sedimentological and chronological tools on polar lake sediments
Why will GLACTIC target Skeiðsvatn – what sets this lake apart from others? And how exactly do you extract sediments from the bottom of an Arctic lake? Stay tuned for our next blog!