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Visiting student at the ice2ice all staff meeting in Myrkdalen, Norway

by Ben Kiesling

From March 13th thru 17th, #ice2ice researchers from Copenhagen and Bergen and a handful of guests from around the world convened in Myrkdalen, Norway, to discuss what the project has achieved to date and how to move forward. As an American PhD student visiting the University of Copenhagen, I was lucky enough to join the Annual Meeting and get a first-hand look at the groundbreaking science the Ice2Ice team is doing.

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The Annual Meeting took place at the bottom of this impressive ski slope.

My first experience with Ice2Ice was in January 2017, when I joined a group of 15 other students at a the week-long ice2ice PhD Bootcamp. I spent that week together with four other PhD students working on ice velocity data from the floating ice tongue of 79ºN Glacier in Northeast Greenland. During the week in January, we were able to accomplish quite a lot, most importantly developing a flexible method for determining the stresses and strains in the floating ice tongue using different datasets. The Annual Meeting in Myrkdalen gave us a chance to get feedback from our mentors and peers and discuss a realistic timeline for moving forward with the project, both of which are invaluable as we work towards publishing our results.

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My bootcamp group getting input on our project from Ice2Ice Scientists.

Although I came to the Ice2Ice meeting to help present my work from the ice2ice PhD bootcamp, I ended up getting much more out of it than I anticipated. Highlights were hearing about ongoing work to understand how the mass balance of the Greenland ice sheet has changed over the last 10,000 years, and to what extent these changes are linked to variations in sea ice. During plenary sessions at the Annual Meeting we discussed how the project has already begun to characterize how changes to the ice sheet and the sea ice affect atmospheric circulation and global climate. Continuing to study these processes is critical for improving our ability to forecast future climate change as Arctic ice cover, on land and in the ocean, continues to shrink. But for me, the most exciting discussions were “off-the-record.” Coffee breaks and afternoon pauses were a great time to catch up with Ice2Ice glaciologists and discuss wild ideas about the past history and future changes to the Greenland ice sheet. I don’t want to spoil anything, but I will say, I look forward to collaborating with scientists from Bergen and Copenhagen long after my visit to Europe ends.

A lot of time was spent talking science at the Annual Meeting, with discussions often spilling over into our shared mealtimes. But it would be a shame (and utterly non-Norwegian!) to travel to such a beautiful place and spend the entire week in a conference room. Our brains brimming with thoughts of Greenland and Dansgaard–Oeschger Events, many of us spent part of the afternoon hitting the slopes. Threatening low clouds and periodic rain would normally have kept me from skiing, but in my experience, it’s hard to spend any time in Norway without really wanting to be outside. And besides, as some of my colleagues liked to remind me, there’s no such thing as bad weather, you just need the right clothes!

Visiting PhD Benjamin Keisling (me!) getting some fresh air in between science sessions.
Visiting PhD Benjamin Keisling (me!) getting some fresh air in between science sessions.

new ice2ice paper-Action at the glacier-ocean interface

by Ruth Mottram and Peter Langen

Glaciers in Greenland lose mass by melt and runoff, by calving and by submarine melt that happens at the front of outlet glaciers that terminate in the ocean. Submarine melt occurs because the ocean water is (relatively) warmer than the ice, but it goes much faster where there is turbulent water mixing the layers by the glacier. Probably the most important source of turbulence are plumes of water that emerge at the base of the glacier where it terminates in the fjord.  The water is generated by melting mostly at the surface though also at the bed of the glacier. Meltwater flows like rivers through systems of englacial channels to finally arrive at the bed where it makes its way, eventually, to the end of the glacier.

Unfortunately these channels are pretty hard to map, and there are lakes and areas at the bed where water can be stored. The plumes themselves are rather hazardous to observe as they are often inaccessible and in front of actively calving sections of the glacier. There have been a few studies, but often these are snapshots in time and it is difficult to assess how important these processes are to the overall mass budget of the ice sheet.

Therefore we have to turn to models to work out how important plume processes are for submarine melt. In our recent paper with Slater et al (2017), we contributed data from the HIRHAM5 RCM to look at runoff within a catchment in Greenland. The case study was based at Kangiata Nunata Sermia glacier, in the Godthåbsfjord area of south western Greenland. It’s a relatively accessible glacier showing many of the common processes for Greenland outlet glaciers and has a fair bit of data available. The Langen et al (2014) paper showed that HIRHAM5 performs pretty well in terms of modelled runoff in this region.

The modelled runoff was used in two different models of subglacial plumes, including one implemented in MITgcm, in order to determine what configuration of subglacial hydrology and plume distribution along the ice front was most likely.  The models were compared with a time lapse photos of the ice front showing plume activity at the surface.

Fig. 1. Illustrations of plume state classification. (a) Plume state=−1, ice tongue present. (b) Plume state= 0, no ice tongue and no surface expression of a plume. (c) Plume state= 1, plume visible adjacent to glacier terminus but is contained within a few hundred metres of the terminus. (d) Plume state= 2, plume visible and flows down-fjord at surface for a number of kilometres.
Fig. 1. Illustrations of plume state classification. (a) Plume state=−1, ice tongue present. (b) Plume state= 0, no ice tongue and no surface expression of a plume. (c) Plume state= 1, plume visible adjacent to glacier terminus but is contained within a few hundred metres of the terminus. (d) Plume state= 2, plume visible and flows down-fjord at surface for a number of kilometres.

For a large proportion of the summer, the modelled catchment runoff greatly exceeds the discharge required to create a plume that would reach the fjord surface, yet there are extended periods when there is no plume visible from the time lapse pictures. This can only be explained by the runoff emerging into the fjord in a spatially distributed fashion. In the paper we therefore argue that subglacial drainage near the glacier terminus is often spatially distributed, formed either from numerous point sources of subglacial discharge, or a single but very wide subglacial channel or possibly a complex combination of the two.

There are two implications from this work. Firstly, a more spatially distributed submarine plume gives a higher total melt than a single concentrated plume but this melt rate is still unable to explain the mass loss at the terminus when considering the ice velocity at the terminus, suggesting that calving is still the most important mass flux term at this glacier. Secondly, the modelling study found that the distributed hydrology, suggested by the results leads to a more direct ice flow response to high surface melt rates and this response most likely scales with catchment size.

Probably the most important result to come out of this study is that longer time series of observations of plumes, in combination with the modelled runoff lead to a dramatically different understanding of key processes within the fjords when compared to those suggested by simple snapshot observations in earlier studies.

Fig. 2. (a) Air temperature from KNS1 and NUKL PROMICE stations. (b) Modelled runoff. HIRHAM5 (orange) delays runoff using a parameterisation based on surface slope. PDD model (green) assumes instantaneous runoff. PDD delay (pink) uses a transit velocity of 0.05 m s−1 from point of production to the terminus. PDD rapid (purple) uses a transit velocity of 1 m s−1. The green curve has been smoothed using a 3 d moving window, the pink and purple curves using a 6 h moving window. Large discrepancies between HIRHAM5 and the PDD model arise due to rainfall events (e.g. days 177 and 181). (c) KNS1 daily ice velocity. (d) Plume state as described in Figure1.
Fig. 2. (a) Air temperature from KNS1 and NUKL PROMICE stations. (b) Modelled runoff. HIRHAM5 (orange) delays runoff using a parameterisation based on surface slope. PDD model (green) assumes instantaneous runoff. PDD delay (pink) uses a transit velocity of 0.05 m s−1 from point of production to the terminus. PDD rapid (purple) uses a transit velocity of 1 m s−1. The green curve has been smoothed using a 3 d moving window, the pink and purple curves using a 6 h moving window. Large discrepancies between HIRHAM5 and the PDD model arise due to rainfall events (e.g. days 177 and 181). (c) KNS1 daily ice velocity. (d) Plume state as described in Figure1.

ice2ice in the media-UN international day of women and girls in science

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Article in ScienceNordic

The 11th of February was the UN international day of women and girls in science.

Both ice2ice postdoc Helle Astrid Kjær and DMI researcher Ruth Mottram has been very active tweeting about ice2ice activities (@H_A_Kjaer and @ruth_mottram) and have also used the #actuallivingscientist, which is used to describe what scientist actually work with. This was picked up by ScienceNordic, which is a news media for Nordic science. They used the two tweets from Helle and Ruth in their article on 11th of February celebrating UN international day of women and girls in science.

The full story can be found in english here.

And in danish here.

Other active ice2ice tweeters are:

 

 

Ice2Ice in the Norwegian news again

klassekampen-8-2-17The Norwegian newspaper Klassekampen has a very nice 2 page article on the ice2ice project. The interview with Principal Investigator Eystein Jansen focusing on abrupt changes in the Arctic climate.

Project partners can find the full text in the ice2ice dropboc

ice2ice in the media -Nordic project will solve a riddle of dramatic climate change

9th of February 2017 ScienceNordic.com featured a long article about the ice2ice project and how we seek to reveal the causes of rapid climate change. The article was written by Catherine Jex , heavily quotes DMI ice2ice researcher Ruth Mottram and also has a video interview with ice2ice Paul Vallelonga as well as with master student Lisa Hauge.

The full article can be found here , a danish version was published at videnskab.dk can be found here. The news story also featured in the large danish newspaper Jyllandsposten.

ice2ice was featured in ScienceNordic
ice2ice was featured in ScienceNordic

 

Holocene workshop in Dronningmolle

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Paul Valleonga and Ray Bradley discussing Greenland temperature trends from lake sediments and ice cores.

The 3-day Ice2Ice Holocene workshop took place from the 23rd to the 25th of January in Dronningmølle, DK. 26 participants mainly from the Ice2Ice network were involved in a dynamic exchange of knowledge and ideas on the climate of the Holocene epoch as seen from different records. The format of the workshop was open and informal something that allowed for more discussions than talks and allowed the participants to present data and ideas.

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Audrey Morley giving a potential explanation of the Holocene climate changes by changes in the position of the atmospheric jet, which could be driven by changes in the latitudinal temperature gradient.
The 2 invited talks from Audrey  Morley (National University of Ireland, Galway) and Camilla Andersen (Geological Survey of Denmark and Greenland) initiated a fruitful exchange of ideas while talks by Martin Miles, Kerstin Perner, Vasileios Gkinis and Trond Dokken gave an overview of the data based picture of the Holocene climate as it is seen in ice and marine cores. Some of the discussions particularly focused on seemingly common climate signals around the mid Holocene and resulted in the initiation of future collaborations and projects integrating climate records focusing in that particular period. There also seems to be anticipation in the promising Bromine records that Niccolo and Paul are working on, the upcoming NEEM water isotope diffusion reconstruction by Vasileios and the planned transient Holocene run by Kerim with focus on the Scandinavian pattern. Future strategies on tephra studies have also been the subject of a discussion on Tuesday evening.
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The tephra team in discussion of future strategies

The art of collaboration – a summary from the Ice2Ice PhD bootcamp

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Photo: Mads Poulsen

The second edition of the Ice2Ice PhD bootcamp recently came to an end, this time held in Geilo in the midst of the Norwegian winter, a couple of hundred kilometers to the east of Bergen. Based on the idea that each PhD student should benefit, in term of hers/his own project, from collaborating with other students working on related problems, the fourteen participating PhD students were divided into three groups several months prior to bootcamp. Within each group, a project was defined and sufficient preparations were made on beforehand such that the bootcamp week provided the ideal surroundings and time to work intensively on the project, and to answer the related scientific questions.

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Photo: Martin Olesen

One group worked on the momentum balance of the Northeast Greenland Ice Stream (NEGIS) outlet glaciers and had a specific emphasize on the potential back-resistance provided by the glacier tongue. Another group investigated the possibility to establish a self-sustained extensive sea ice cover in the North Atlantic in a coupled general circulation model by assimilating sea ice in an energetically consistent way. The last group focused on comparisons of proxy records obtained from sediment- and ice cores, specifically sea ice reconstructions based on Bromine enrichment as seen from the Greenland ice sheet and concentrations in sediments of organic matter from diatoms that live below the sea ice edge. Each group were guided by a mentor of their own choice, who were either available through a web connection throughout the week or were present at the bootcamp itself.

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Photo: Mads Poulsen

Besides the group work, the bootcamp also hosted scientific talks by mentors Rasmus Anker Pedersen (PostDoc, Centre for Ice and Climate) and Lars Henrik Smedsrud (Professor, University of Bergen) as well as student-organized seminars on plotting possibilities with python and GMT, and proxy interpretations and uncertainties. The week culminated with a presentation by each group on the results obtained during the bootcamp and on the possible prospects.

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Photo: Martin Olesen

Despite the military discipline which is associated with a bootcamp, the week did allow for a few cultural and social inputs. The owner of the bootcamp venue gave a brief introduction to the Hardanger fiddle, a delicate Norwegian instrument, and during Thursday a couple of hours of break were taken away from science as the groups went for a 5km dog sledge ride in the outskirt of Geilo.

 The results from the three groups, as well as the perspectives and the possibilities to integrate the projects further into the Ice2Ice synergy, will be presented on the all-staff meeting in Myrkdalen in March.

ERC featuring Ice2ice in their recent newsletter

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ERC writes in its newsletter “With an ERC Synergy Grant, Prof. Jansen and three Nordic world class researchers are currently investigating the dramatic loss of Arctic sea ice.”

In their last newsletter of 2016 the European Research Council (ERC) puts the spotlight on the ice2ice project and writes: “With an ERC Synergy Grant, Prof. Jansen and three Nordic world class researchers are currently investigating the dramatic loss of Arctic sea ice.” The article includes a picture of the flagpole on top of the Renland ice cap in East Greenland that mark the multinational effort.

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Science diplomacy

In October the ERC arranged a conference focusing on how frontier research can contribute to science diplomacy. The conference included a presentation of the ice2ice project presented by the Ice2Ice Coresponding Principal Investigator Eystein Jansen.

In the editorial to the newsletter, Federica Mogherini, the High Representative of the European Union for Foreign Affairs and Security Policy and Vice President of the European Commission, writes “Scientific cooperation in the Arctic can help stabilise an area where there is much potential for collaboration as there is for competition.”

ERC to reinstate Synergy Grants call

ERC has also announced that they will open another call for Synergy Grants and there is an article covering this in the newsletter. In 2014, the Scientific Council established an ad hoc group tasked with assessing the outcomes of the two synergy calls. In March last year ice2ice was the first project that the evaluation committee would meet with and we believe that this meeting has strongly contributed to the fact that the group recommended reinstating the synergy grant scheme.

Based on the groups findings the ERC President stated: “The Synergy Grants awarded so far have shown that this funding fosters interdisciplinary research and can trigger unconventional collaborations, allowing for the emergence of new fields of study. They will contribute significantly to fill a gap in EU funding for frontier research.” The decision to open another Synergy Grants call is welcomed by the Ice2ice team.

A warm arctic

The Warm Arctic workshop was held at DMI on the 5th and 6th December with several invited guest speakers from outside the ice2ice group. Svend Funder and Kurt Kjær from the Centre for Geogenetics at the Natural History Museum of Denmark in Copenhagen gave a good introductory overview of the current state of the art in terms of paleoproxies for Arctic sea ice extent and ice sheet extent in Greenland respectively. This was excellent framing for the remainder of the workshop.

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Sea ice processes are not straight forward. credit Vihma

Timo Vihma from the Finnish Meteorological Institute contributed an interesting talk on connections between the Arctic and the mid-latitudes including a very comprehensive diagram showing important processes and linkages, while on the second day, external speakers Wieslaw Maslowski and Dirk Notz (remotely) gave a nice overview of the state of the sea ice modelling from their respective groups, leading to an intense discussion on whether the ocean or the atmosphere was the dominant driver of change in the Arctic. Dirk Notz work shows nicely that sea ice decline follows emissions pretty directly. Internal speakers from DMI, included Rasmus Tonboe who gave a good overview of current sea ice data available from EUMETSAT and Torben Schmidt handled the modelling side with a look at multidecadal variability in the Arctic ocean.

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Notz talked about the effect of global CO2 on sea ice

Various ice2ice members also gave talks on different aspects of the project including a presentation by Shuting Yang on the Arctic sea ice loss and Northern hemisphere winters. There was a very comprehensive discussion by Peter Langen on Greenland ice sheet surface mass balance, some early work from Martin Stendel on the Arctic seesaw when there is little or no sea ice and PI Jens Hesselbjerg Christensen on the state of sea ice in a 1.5C world (spoiler: there won’t be very much). Rasmus Anker Pedersen also showed some of his work on the atmospheric response to a sea ice free Arctic.

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credit Svend Funder

As the aim of the workshop was to produce a review paper on the subject, there were two wide ranging discussion sessions where a very wide range of related topics were explored, including the aforementioned question of the relative importance of ocean and atmosphere and how the processes and feedbacks between the two might look. There was also much discussion on ways to improve sea ice representations in models and the importance of both including more comprehensive processes and improved model resolution in both ocean and atmosphere models. Finally, the workshop participants structured these issue into a format to create both a publication and potentially a conference session in the future, watch this space!

The workshop was organized by Christian Rodehacke, Peter Langen, Shuting Yang and Jens Hesselbjerg and was held at DMI.

Video: Ice cores – Revealing secrets of a past climate

Ice cores from the ice streams of north-eastern Greenland can tell us much about the climate of the past as well future sea level rise. Learn more in the video above.

For the first time an international group of scientists will drill a deep ice core into a fast flowing ice stream on Greenland. The international project EastGRIP, is lead by Ice2Ice parter Centre of Ice and Climate at the University of Copenhagen.

During the summer of 2016 a team of researchers and students built the base on the ice stream in northeast Greenland, started a comprehensive scientific surface field campaign, and initiated the ice core drilling.

The aim of the project is to better understand the dynamics and properties of the fast flowing ice stream. By the time they reach bedrock in the year 2020, the team will have extracted nearly 2700m of Greenland ice giving a 100,000 year old climate archive.