Promoting gender balance and improved recognition of female researchers at conferences: some thoughts and guidelines for best practise

equity-2355700_960_720The issue of unequal representation of women and men at academic conference is not a new topic, but it has often been on my mind in recent weeks following experiences and observations as both a conference organiser and attendee/presenter. I’ve had multiple constructive, encouraging discussions around this topic with people of varying gender and career stage, and through this article I hope to summarise some of the ideas arising from these discussions which organisers, conveners and attendees can put in place to promote gender parity in future meetings. I know that many individuals and organisations are working hard to effect change on this issue, and some of the material below may be obvious or already being applied, However, it’s clear that there is still significant room for improvement, and as long as there are still conference sessions where all speakers are men, in my view, we must do more to achieve a gender balance.


Encouraging attendance and abstract submission

  • Earmark in-house funding for ECR female attendance where funds are available and flag external opportunities for conference attendance funding such as the Gill Harwood Memorial Fund from the BSRG.
  • Offer childcare subsidies if possible, and strive to acquire sponsorship to contribute towards funding of crèche facilities and childcare.
  • Solicit abstracts from female researchers to encourage submission to meetings and individual sessions, with a particular focus on talks. By contacting researchers directly they may feel more welcome and their academic contribution more appreciated.
  • Try to achieve gender balance when inviting keynote speakers. In conferences with multiple sessions/specialisms this should be reviewed by the organising committee to ensure gender balance across the event and not only at session level.
  • Ensure gender balance in session conveners/co-conveners. Having a good gender balance in the organising committee, session conveners, and invited keynotes can be used to advertise a meeting/session and create a positive, inclusive vibe.


Achieving session diversity

  • Strive for an equal gender balance of speakers, even if (where appropriate) this results in “positive” discrimination in favour of women. The visibility of female speakers may act to encourage increased female attendance and abstract submissions in future meetings/sessions.
  • If an oral session looks likely to be dominated by male speakers while the poster session has a larger proportion of women, think about getting in touch with individuals to ask whether they would consider giving a talk. This may not be possible where the abstract submission process is very formal (highlighting the need to solicit female contributions early on).
  • It has been observed that men are more likely to ask questions during oral sessions even where conference gender balance is 50/50, but one study suggests that women are more likely to ask questions if a female is first to ask. Convenors could thus try to vary between men and women being given an opportunity to ask the first question after a talk. Individual institutions and organisations could also try to improve the confidence of ECRs of all genders in engaging with questions and discussion by implementing ideas such as “question club”.


Facilitating the needs of attendees

  • Be aware of diverse needs when choosing a conference venue. I witnessed multiple instances of people with children and buggies struggling with non-automatic doors at the very busy entrance to EGU last week, for example. Ensuring accessibility is important not only for attendees with children, but also for those with disabilities and mobility issues.
  • Try to set aside quiet/private spaces with adequate facilities for breastfeeding, pumping and other childcare needs.
  • Strive to offer childcare/crèche facilities, and spaces for play.
  • Consider inclusion of priority seating in oral and poster sessions, ensuring that pregnant women, and indeed those with reduced mobility, have access to seats should they need them.
  • Facilitate the attendance of family members and caregivers. Given that many countries and organisations still do not offer full equality in parental leave, promoting family conference attendance may better support female researchers.
  • More on this topic can be found in this recent article in PNAS.


Diversity in roles and accolades

  • Conferences often involve medal ceremonies for researchers being recognised for their contribution to a specific field. Medal ceremonies and lectures are a visual display of excellence, and thus achieving gender balance here is imperative to encourage female ECRs to continue in their research careers. When soliciting nominations for these awards organisers may wish to highlight that the full range and diversity of the research community should be considered when nominating and voting for candidates. Ultimately it is up to the community as a whole to do better on this point; when calls for nominations come around the mailing lists, act! (Only 21.1% of nominees for EGU awards in 2018 were female, for example).
  • Both conference organisation and convening can be viewed as prestigious roles, and may even contribute towards career progression. Committees should thus strive to encourage female participation in conference organisation, while sessions without female co-convenors could consider inviting additional female contributors.
  • More broadly, female representation in organisations and committees must be improved across a range of roles and levels. Furthermore, females must have an equal opportunity to take on the most prestigious roles (and not only roles in outreach and networking, which are often taken on more by minority groups).

The EGU 2016 Awards Ceremony… promoting equality? (Credit: EGU/Foto Pflueg)


Considerations for conference attendees

  • When organising networking or social events (both formally and informally) be mindful to avoid bias against those of a different gender. Given that ideas for new projects and collaborations can often arise outside of formal conference sessions, post-conference socialising and networking must be inclusive to allow equal opportunity for future research engagement. As with many of the points raised here, this issue is important not only in terms of gender balance, but also for all minority groups.
  • Transparent guidelines for appropriate behaviour, including a policy on sexual harassment, should be considered, particularly for large events. These guidelines must be clearly-communicated and easily navigable, helping to ensure that all attendees feel comfortable and safe during the conference. AGU have made positive progress on this, including the implementation of the “SafeAGU” programme.
  • Finally, all conference participants should be aware of their own behaviour during sessions. I’ve seen multiple cases of ECRs (particularly females) being questioned/criticized in an aggressive and non-constructive manner following what might be their first oral presentation at a large conference. While I certainly do not want to see sessions where constructive criticism is not welcomed, attendees should be mindful of where public criticism is appropriate.


This is not intended to be an exhaustive list of guidelines, nor can all of this be achieved immediately or at every conference. Many of these guidelines can be implemented simply by a change in research culture and through community buy-in, while others will require investment in the form of infrastructure and funding. I’d like to thank all of the men and women who flagged many of the ideas above to me in recent weeks, and I very much welcome additional input and open discussion around this topic in the future.

Dr Caroline Clason, 15th April 2018

Creating gender balance at academic conferences: a reflection on recent experience and the elephant in the room

Earlier this month the School of Geography, Earth and Environmental Sciences at the handbook_coverUniversity of Plymouth hosted the QRA (Quaternary Research Association) Annual Discussion Meeting. This three day conference welcomed delegates from across the UK, Europe and further afield, and across all research career stages from masters students to professors. The overarching theme of the conference was data-model inter-comparison in Quaternary Science, with session themes spanning landscape evolution and palaeohydrology, long-term ecology, palaeoclimate reconstructions, glacial modelling and geomorphology, and sea level change. From the offset the 2018 QRA meeting was organised with gender balance in mind, including the make-up of organising committee, invited keynotes and session chairs, and the programme of talks. As the lead of the organising committee I was supported by both male and female colleagues, and while the task of organisation was a significant drain on time, at no point did I feel in any way that my efforts were not appreciated.

I am passionate about equality in STEM and academia more broadly. One of the responsibilities of my job is to sit on the Equality, Diversity and Inclusivity Committee in my school, where we look for ways to promote gender equality across a wide variety of academic activities, including the departmental seminar series, interview committees, and academic administrative roles. With a growing impetus for improved gender balance in academia, it’s imperative to consider not only how we might improve equality within our own institutions, but also how we can promote equality and diversity in the wider academic community. Conferences are an important platform upon which early career researchers can build networks, meet potential future collaborators and employers, and receive essential feedback on their work from other experts in the field. I’m all too aware from my own experiences that conferences are not always a positive experience for women, with the gender balance of presentations often far from equal. Furthermore, I know of senior women reduced to tears by aggressive questioning by other delegates, with the sometimes intimidating atmosphere of conference halls acting as a barrier to less “confident” delegates being willing to pose questions or voice their opinions. A recent article published in Times Higher Education  describes a study which found that women are two and half times less likely to ask a question during an academic seminar than men, and that female respondents to one survey were more likely to report feeling intimidated, nervous, or not clever enough as a reason for their reticence to ask a question.

With this article in mind, my colleague and I made note of the gender of every person who asked a question during the QRA meeting. The results of this survey, in addition to other variables including delegate numbers and gender balance of speakers, are summarised in the table below.

Male Female
Conference attendees 44 (54%) 38 (46%)
Talks presented (including invited keynotes and drop-outs/stand-ins) 23 (56%) 18 (44%)
Posters presented 11 (39%) 17 (61%)
Talks requested (on submission of an abstract) 23 (56%) 18 (44%)
Talks allocated by the organising committee 21 (57%) 16 (43%)
Keynote speakers 2 (40%) 3 (60%)
Session chairs 3 (60%) 2 (40%)
Organising committee members 4 (44%) 5 (56%)
Questions asked during the programme of talks 80 (77%) 24 (23%)

Let’s start with addressing the elephant in the room: 77% of questions during the meeting were asked by men, more than three times the number asked by women. There’s no way to dress this up as anything other than depressing reading, however having attended every session during the conference, and having presented a talk myself, I witnessed no aggressive questioning to either male or female speakers and certainly do not feel that the atmosphere of the meeting was either intimidating or unsupportive. Looking at the gender balance of conference attendees, talks requested and talks presented, I believe that we achieved a very good gender balance both in terms of conference delegates and the programme of talks. Quaternary science is a research field that has been historically dominated (in number at least) by men, however my recent experience of organising this conference fills me with genuine optimism that we are headed in the right direction. Achieving this gender balance was a core priority of the organising committee. We actively chose to invite three (excellent) female keynote speakers, maintained the proportion of talks requested and talks presented by women, and perhaps by selecting a female lead for the organising committee we played a small part in influencing the attendance of female delegates.

All things considered, these numbers give me cause to be happy, and contribute to what was an overwhelmingly encouraging conference experience. A number of delegates, including high-profile keynote speakers, commented positively on the gender balance of the conference programme, and I very much hope that the other attendees and presenters had a similarly positive experience, particularly those in the early stages of their research career. But what to do about the elephant in the room? How can we affect change not only in who attends and presents at conferences, but also in who feels comfortable and confident enough to make their voice heard? Unsurprisingly, I don’t have the answer, and our data are insufficient to offer additional insight. What I would suggest, however, is that this exercise should be repeated on a larger scale (EGU, AGU or INQUA for example). This might allow for a more detailed analysis of whether sessions with a greater proportion of female presenters also promote greater numbers of questions from female delegates, whether the gender of session chairs influences the proportion of males vs females who ask a question or make a comment, and whether females are more likely to ask a question if the first person to ask is also female.


Ralph Fyfe, Stephanie Mills and Caroline Clason – three happy conference organisers!

To finish, I want to briefly touch upon the importance of not only retaining females who have chosen to enter the world of academia (a huge issue in itself) but also on attracting female school-leavers into the geosciences and STEM in the first place. “Girls into Geoscience” is an initiative to introduce female A-level students to the Earth Sciences, including a field trip, workshops led by female academics, and seminars from women who work in the geosciences. The next event will be held at the University of Plymouth this July, and you can follow us on Twitter if you’re interested!

Dr Caroline Clason, 24th January 2018

Pells, R., (2017), Men ‘much more likely to ask questions in seminars’ than women, Times Higher Education, available at (accessed 24/01/2018)

Coring and cricket

We’ve been at Tarfala Research Station for a week now, and making great progress with our sampling schedule! Unfortunately, the weather has well and truly called a halt to fieldwork due to rain/snow/hail/gale force winds, but we’re making the most of it by staying warm and dry and catching up with processing our ice surface sediment samples in the lab (and discovering just how smelly cryoconite is while drying in the oven!).


Cryoconite sampling on Isfallsglaciären

In addition to completing our sampling of the moraines and proglacial stream outlets, we also had a go at taking a sediment core from the bottom of one of Isfallsglaciären’s proglacial lakes. To do this we carried a dinghy from Tarfalasjön to Isfallssjön across multiple moraines, which turned out to be a seriously physical task! Coring proved to be much trickier than expected as the proglacial sediments are very fine and dense and the corer struggled to penetrate the sediments at the lake bottom. Although this was a disappointment, and we ended up having lunch in a bothy bag to shelter from the bad weather, taking the boat out on Isfallssjön was a a really fun experience… We’ll try again when the weather improves!


Boating in Isfalls proglacial lake

We’re really glad that we decided to front-load our fieldwork schedule and have collected most of what we need, as the weather is really putting a spanner in the works at the moment. Good company and nightly saunas are going a long way to keeping spirits high! To end on a VERY positive note, following some cricket coaching from Nick and I (the only Brits at the station), Team Tarfala went on to win back the “Ashes” from Kebnekaise Mountain Station at the annual cricket match! HOWZAT?!!!


Evening cricket practise… Tarfala style!

This blog post was first published at on 14th August 2017 as part of our INTERACT project, “GRASP” (glacier recession as a source of environmental pollutants).

Let the sampling begin!…

After journeying from Plymouth by car, plane, bus, and helicopter, we arrived at Tarfala Research Station in Arctic Sweden on Monday 7th August (a very happy moment for me after a long three years since my last visit!). We were greeted by Tobbe and the station staff and immediately made to feel at home, and began our fieldwork on Monday afternoon by scoping out our field site on and around Isfallsglaciaren.


We have begun our field campaign by collecting samples of cryoconite from the surface of Isfallsglaciaren, and taking sediment samples from the proglacial stream outlets, moraines, and fluted glacier forefield, for eventual analysis back in Plymouth. Isfallsglaciaren has retreated significantly over the past century, leaving behind a dynamic and very beautiful proglacial area, which makes fieldwork here a joy (even the rain couldn’t dampen spirits completely…)!

20626731_10100532978455939_1162783574090808102_o  P1010562

Processing the samples (drying and separating fine sediments) at the end of the day is a bit of a slow process with so many samples to get through, but we’re looking forward to more exciting field days ahead both on the glacier and when we take the boat onto Isfallssjon to take a sediment core from the proglacial lake. It’s been a great start to our visit so far, and we’re looking forward to the rest of our time here at Tarfala!


This blog post was first published at on 9th August 2017 as part of our INTERACT project, “GRASP” (glacier recession as a source of environmental pollutants).

Using the past to inform the future: the role of palaeoglaciology

The study of glaciers and ice sheets has traditionally been split into three communities: those conducting observational research of the present day cryosphere; those developing theory and models to simulate cryospheric processes; and those who use the palaeo record to interpret glaciations of the past. Isolation of these three branches of glaciology can hinder both improved understanding of physical glacial processes and improved interpretations of the palaeo record. In a recently published paper (Greenwood et al., in press) my colleagues and I reviewed the current state of knowledge of one aspect of glaciology (ice sheet hydrology) from the perspectives of these three research communities. The paper further discussed key questions and uncertainties in understanding of the glacial hydrological system, leading to conclusions including: that the traditional bi-modal view of subglacial hydrology is challenged by both modern observations and palaeo interpretations; that we do not fully understand the extent to which different landforms represent different drainage modes or are different expressions of one drainage mode; and that the geomorphic imprint of the multitude of frequencies and magnitudes (figure 1) of drainage events remains poorly understood. These conclusions highlight only some of the many research challenges for the glaciological community which cross-disciplinary cooperation could help to tackle.


Figure 1. Peak discharge circles, scaled by area. The peak discharge of the Glacial Lake Missoula floods is 340000 times greater than the Adventure Trench drainage; like comparing the Amazon River with a small brook. From Greenwood et al. (in press).



Figure 2. Glacial lineations visible on the sea floor: A) rat tails c. 200 m long; B) drumlins c. 1-2 km long; C) mega scale glacial lineations c. 10-20 km long; D) lineations of cross-cutting directionality (pink and blue).

Our understanding of physical glaciological processes, and controls on the stability, dynamics and retreat of ice sheets must continue to improved if we are to better predict ice sheet sea level contribution in response to future climatic change. Accessing the proglacial and subglacial environments of ice sheets to observe processes first-hand is, however, very much restricted due to both logistical and safety constraints. Furthermore, despite the advent of remote sensing, observational records from present-day ice sheets are short (up to tens of years) in comparison to glacial cycles (thousands of years). The glacial landform record, a footprint of previous glaciations left behind on both present day land and the sea floor, provides a window into these environments, and a great deal of insight into the processes operating beneath past ice sheets. Mapping and analysis of glacial landforms can reveal a significant amount of information, including the direction and speed of ice flow, the topology of the subglacial hydrological system, the retreat pattern of the ice sheet margin, and the extent of iceberg calving activity. As an example figure 2 illustrates some of the multitude of forms of glacial lineations, from which both direction and relative speed of ice flow can be interpreted.


Figure 3. Flow path of the Bothnian Sea ice stream inferred from glacial lineations. Longer lineations depicted in green, shorter lineations in red. From Greenwood et al. (2015).

Marine-terminating catchments are the source of much of the mass loss from the Greenland and Antarctic ice sheets, sensitive to changes in both climate and in the ocean. It is thus particularly important to better understand controls on marine ice sheet instability if we are to predict the effect of future atmospheric and environmental change. Recent work in the Gulf of Bothnia region of the past Fennoscandian Ice Sheet gives a unique insight to the dynamics, retreat pattern, and processes operating under a marine-terminating ice stream during the last deglaciation. In addition to ongoing modelling work and data analyses, mapping of glacial lineations allowed us to identify the onset of fast ice flow from the north-east Swedish coast (Greenwood et al., 2015; figure 3). Relating bedform length to relative ice flow speed (Stokes & Clark, 2002), the ice stream width was constrained by a sharp transition between relatively short and relatively long lineations visible on both present day land and the sea floor. Aside from an improved understanding of ice dynamics and retreat in this region of the Fennoscandian Ice Sheet, this research offers a unique perspective on marine-terminating ice stream catchments. The broad, shallow, low salinity setting of the Gulf of Bothnia contrasts with the topographically-constrained continental shelf settings typical of studies of present-day marine outlet glaciers. Palaeoglaciological study can thus improve our understanding of the multitude of responses exhibited by ice sheets, in a range of geographical settings, to external forcings.

In concert with palaeo proxies for reconstructing past climates and environments, glacial landforms can provide a record of long-term response to changing conditions. The study of ice sheets of the past can thus offer important insights to ice sheet response in the future. There is a real danger of isolation between glaciological research groupings, leading to disconnects in understanding of processes important for predicting the future response of present day ice sheets to a warming climate. Fostering cross-disciplinary research is imperative if the true diversity of processes and controls exhibited by contemporary ice sheets are to be understood; using the past to inform the present, and vice versa.


Greenwood, S.L., Clason, C.C., Mikko, H., Nyberg, J., Peterson, G. & Smith, C.A., (2015), Integrated use of LiDAR and multibeam bathymetry reveals onset of ice streaming in the northern Bothnian Sea, GFF, DOI:10.1080/11035897.2015.1055513

Greenwood, S.L., Clason, C.C., Helanow, C. & Margold, M., (in press), Theoretical, contemporary observational and palaeo perspectives on ice sheet hydrology: processes and products, Earth-Science Reviews, doi:10.1016/j.earscirev.2016.01.010

Stokes, C.R. & Clark, C.D., (2002), Are long subglacial bedforms indicative of fast ice flow?, Boreas, 31 (3), 239–249, doi:10.1080/030094802760260355

Paper overview: Modelling the transfer of supraglacial meltwater to the bed of Leverett Glacier, Southwest Greenland

Figure 1. Moulin on Leverett Glacier, southwest Greenland

Figure 1. Moulin on Leverett Glacier, southwest Greenland

The delivery of surface-generated meltwater to the subglacial (basal) environment beneath glaciers and ice sheets is a driver of increased ice flow through raising water pressure in subglacial hydrological systems and lubricating the interface between the base of the ice and the rock or sediment beneath. The extent to which this surface-to-bed meltwater transfer influences the average annual ice velocities of outlet glaciers on the Greenland ice sheet is debated, but we know that at least in the short term, the delivery of meltwater into the subglacial system promotes localised acceleration of ice flow (e.g. Bartholomew et al., 2011a: Hoffman et al., 2011). Our new paper in The Cryosphere describes the application of a model for predicting the formation of moulins (figure 1) and the drainage of supraglacial lakes (surface meltwater ponds) to the bed of the Leverett Glacier catchment in southwest Greenland.

Figure 2. a) Daily average air temperatures at 457 m a.s.l. for 2009 and 2010, and moulin formation and lake drainage through the b) 2009 and c) 2010 melt seasons with elevation. Blue diamonds in panel b) represent observed drainage of lakes in events between two MODIS images, and red diamonds represent lakes which drained over a period of several MODIS images; after figure 2a of Bartholomew et al. (2011a).

Figure 2. a) Daily average air temperatures at 457 m a.s.l. for 2009 and 2010, and moulin formation and lake drainage through the b) 2009 and c) 2010 melt seasons with elevation. Blue diamonds in panel b) represent observed drainage of lakes in events between two MODIS images, and red diamonds represent lakes which drained over a period of several MODIS images; after figure 2a of Bartholomew et al. (2011a).

The model can be split into three main components: the generation of meltwater at the surface through melting of snow and ice; the routing of meltwater across the ice surface and storage in supraglacial lakes; and the propagation of fractures through the ice driven by water pressure from meltwater inflow. The outputs of modelling provide information on the timing and location of moulins penetrating from the surface to the bed of the ice, the timing and location of the drainage of lakes through hydrofracture, the storage of meltwater in the supraglacial and englacial (internal) hydrological systems, and the quantity of meltwater reaching the glacier bed.

The results of our modelling were compared with ice surface velocities measured with a series of 6 GPS stations (Bartholomew et al., 2011a) and observations of supraglacial lake drainage events (Bartholomew et al., 2011b) in the Leverett glacier catchment. The pattern of modelled lake drainages compared favourably with that observed from satellite imagery during 2009 (figure 2) . Modelling for the 2010 melt season produced a 44% increase in the number of lakes which drained, with lake drainages starting earlier in the season and occurring more frequently at higher elevations in comparison to the cooler 2009 melt season. Formation of moulins in both years occurred at increasing elevation with time into the melt season, reflecting retreat of the snowline and water availability for driving fractures through thicker ice inland of the margin.

Figure 3. Supraglacial meltwater delivered to the bed each day through modelled lake drainages, moulins, and for the control simulation within ice surface elevation bands of 250 m during 2009. Ice surface velocities from GPS sites 1 – 6 are plotted within their respective elevation bands (after Bartholomew et al., 2011b).

Figure 3. Supraglacial meltwater delivered to the bed each day through modelled lake drainages, moulins, and for the control simulation within ice surface elevation bands of 250 m during 2009. Ice surface velocities from GPS sites 1 – 6 are plotted within their respective elevation bands (after Bartholomew et al., 2011b).

To demonstrate the need to account for supraglacial storage and routing of meltwater, and the ability of that water to reach the ice sheet bed through hydrofracture, we conducted a control simulation where all surface-generated meltwater was transferred locally and instantaneously to the bed. The importance of accounting for this was particularly apparent above 750 m a.s.l. (figure 3), where discharge modelled including supraglacial storage, routing and hydrofracture greatly outperformed the control simulation when compared against measured ice surface velocities. Modelled surface-to-bed meltwater transfer characterises well the up-glacier progression of increased ice surface velocities, with the relative contribution of meltwater drained through lakes increasing with elevation.

Figure 4. Density of moulins and lake drainages predicted for the IPCC (2007) A1B mean June, July and August Arctic scenario for temperature change within 250 m ice surface elevation bands.

Figure 4. Density of moulins and lake drainages predicted for the IPCC (2007) A1B mean June, July and August Arctic scenario for temperature change within 250 m ice surface elevation bands.

With meltwater production rates responding to increases in air temperature, we tested our model with a future climate scenario (IPCC 2007, A1B June, July, August Arctic scenario) to investigate possible future changes in the occurrence of ice surface-to-bed meltwater transfer. The density of moulins and drained lakes at higher elevation in the Leverett catchment increased in response to this temperature forcing (figure 4), giving a 68 % increase in moulin numbers, 182 % increase in the drainage of supraglacial lakes, and, most importantly, a 14 % increase in the proportion of surface-generated meltwater reaching the glacier bed. At elevations above 750 m a.s.l. these increases result in more widespread delivery of meltwater to the bed through ice of large thickness, beginning earlier in the melt season.

While below the ELA (equilibrium line altitude – the average elevation on a glacier where snow accumulation equals ice melt) ice dynamic response to meltwater inputs may be negligible over annual time scales (e.g. Sole et al., 2013), above the ELA we may expect a positive relationship between summer temperatures (and melt rates) and ice surface velocities where efficient subglacial drainage of meltwater is hindered by large ice thicknesses and shallow ic surface slopes (e.g. Meierbachtol et al., 2013). Crucially, the implications of a warming climate and increased ice surface melt for subglacial drainage configuration and ice dynamics are difficult to assess fully without incorporating a model such as this into models of subglacial drainage and ice flow. This work thus contributes to efforts to couple physically based models of surface meltwater generation, subglacial hydrology and ice sheet dynamics, as are required to better understand past, current and future sensitivity of ice sheet mass balance and dynamics to climate change.

The full paper is available to read here.


Bartholomew, I. D., Nienow, P., Sole, A., Mair, D., Cowton, T., King, M. A., and Palmer, S., (2011a), Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations, Earth and Planetary Science Letters, 307, 271–278

Bartholomew, I., Nienow, P., Sole, A., Mair, D., Cowton, T., Palmer, S., and Wadham, J., (2011b) Supraglacial forcing of subglacial drainage in the ablation zone of the Greenland ice sheet, Geophys. Res. Lett, 85, L08502

Hoffman, M. J., Catania, G. A., Neumann, T. A., Andrews, L. C., and Rumrill, J. A., (2011), Links between acceleration, melting, and supraglacial lake drainage of the western Greenland Ice Sheet, Journal of Geophysical Research: Earth Surface, 116, F04035

Meierbachtol, T., Harper, J., and Humphrey, N., (2013), Basal drainage system response to increasing surface melt on the Greenland ice sheet, Science, 341, 777–779

Sole, A., Nienow, P., Bartholomew, I., Mair, D., Cowton, T., Tedstone, A., and King, M. A., (2013), Winter motion mediates dynamic response of the Greenland Ice Sheet to warmer summers, Geophys. Res. Lett., 40, 3940–3944

New paper: Dye tracing for investigating flow and transport properties of hydrocarbon-polluted Rabots glaciär, Kebnekaise, Sweden

Our new paper about the application of dye tracing to investigate the flow of pollutants on Rabots glaciär has just been published online in Hydrology and Earth System Sciences Discussions, and you can find a link to it here.




Over 11 000 L of hydrocarbon pollution was deposited on the surface of Rabots glaciär on the Kebnekaise Massif, northern Sweden, following the crash of a Royal Norwegian Air Force aircraft in March 2012. An environmental monitoring programme was subsequently commissioned, including water, snow and ice sampling. The scientific programme further included a series of dye tracing experiments during the 2013 melt season, conducted to investigate flow pathways for pollutants through the glacier hydrological system, and to gain new insight to the internal hydrological system of Rabots glaciär. Results of dye tracing reveal a degree of homogeneity in the topology of the drainage system throughout July and August, with an increase in efficiency as the season progresses, as reflected by decreasing temporary storage and dispersivity. Early onset of melting likely led to formation of an efficient, discrete drainage system early in the melt season, subject to decreasing sinuosity and braiding as the season progressed. Analysis of turbidity-discharge hysteresis further supports the formation of discrete, efficient drainage, with clockwise diurnal hysteresis suggesting easy mobilisation of readily-available sediments in channels. Dye injection immediately downstream of the pollution source zone revealed prolonged storage of dye followed by fast, efficient release. Twinned with a low dye recovery, and supported by sporadic detection of hydrocarbons in the proglacial river, we suggest that meltwater, and thus pollutants in solution, may be released periodically from this zone of the glacier hydrological system. The here identified dynamics of dye storage, dispersion and breakthrough indicate that the ultimate fate and permanence of pollutants in the glacier system is likely to be governed by storage of pollutants in the firn layer and ice mass, or within the internal hydrological system, where it may refreeze. This shows that future studies on the fate of hydrocarbons in pristine, glaciated mountain environments should address the extent to which pollutants in solution act like water molecules or whether they are more susceptible to, for example, refreezing into the surrounding ice, becoming stuck in micro-fractures and pore spaces, or sorption onto subglacial sediments.



Evaluating the environmental impact of a plane crash on a melting glacier in Arctic Sweden

Figure 1. Clean-up operation in the accumulation zone of Rabots glaciär

On the 15th March 2012 a Royal Norwegian Air Force Lockheed Martin C-130J Super Hercules aircraft crashed into the western face of Kebnekaise (Sweden’s highest mountain) in Lapland, during a military exercise. In addition to five fatalities, the crash deposited some 11000 litres of kerosene jet fuel across the mountain wall, snow and ice, which was then further distributed following a large avalanche triggered by the crash. Debris from the crash has been found on Storglaciären, Björlings glaciär, and near the summit of Kebnekaise, but the majority of debris and fuel was deposited on Rabots glaciär, and the pollution was not subject to any immediate decontamination efforts. While much of the aircraft debris has now been removed during clean-up exercises by the Swedish Military (Figure 1), little was known about the fate of the hydrocarbon pollutants.

Figure 2. Rabots glaciär location and pollution source zone (from Clason et al., submitted)

Figure 2. Rabots glaciär location and pollution source zone (from Clason et al., submitted)

Rabots glaciär is subject to ongoing terminus retreat and thinning, and responds more quickly to climatic changes than neighbouring Storglaciären (Brugger, 2007). Although the Rabots glaciär catchment is in a very remote location, the glacier meltwater outlet (proglacial river) feeds rivers used for drinking water by numerous backpackers and the local Sami, who work with reindeer husbandry along the banks of the Kaitum river system. With a possibility for environmental, social and economic impacts arising from water pollution in this region, it is imperative to evaluate the evolution of the polluted area and mechanisms for hydrocarbon pollutant dispersal from the source zone (Figure 2) in the accumulation area of Rabots glaciär. To tackle this, a monitoring programme has been run by researchers at Tarfala Research Station and Stockholm University (led by Gunhild Rosqvist, myself, and Jerker Jarsjö), including repeat sampling in the snowpack, ice/firn, and the proglacial river for chemical analysis to detect jet fuel components. To investigate the pathways and transit times of pollutants from the source zone (Figure 2), a series of dye tracing tests were conducted as a proxy for flow of pollutants in solution through the glacier system (Clason et al., submitted). In these tests an instrument called a fluorometer detects the emergence of the dye in the proglacial river, following initial injection into flowing water above a moulin (Figure 3), a vertical shaft in the ice which provides entry for meltwater to the internal and subglacial drainage systems. Dye tracing experiments provide an indirect method for understanding what the hydrological system inside and underneath a glacier may look like, how fast and efficiently meltwater flows through a glacier, and the extent to which meltwater is stored during its journey through glacier.


Figure 3. Injection of the water tracing dye rhodamine into a supraglacial stream directly above a moulin on Rabots glaciär.

The results of dye tracing revealed likely storage of meltwater and pollutants near the source zone within or beneath the glacier, released in pulses when sufficient water flux from precipitation or melting flushes out the hydrological system. This was supported by infrequent, sporadic detection of pollutants in the proglacier river. The levels of pollutants detected are not thought to currently be a threat to the drinking water supply, but under conditions of higher melting in a warming climate, the frequency and levels of pollution released into the river system could increase. Based on the solubility of the hydrocarbon compounds of the fuel, the lifetime of these compounds in the source zone on Rabots glaciär was modelling with a coupled melt-mass flux modelling approach (Clason et al., in preparation). Assuming no change in summer melting conditions (based on 2013 meteorological data), and perfect contact between the meltwater and the fuel compounds, some of the lighter hydrocarbon compounds have likely already left the glacier. However, heavier components have the potential to persist for tens of thousands of years, far outliving the glacier itself.

Under warming climate scenarios we may see increased interaction of these jet fuel compounds with the surrounding pristine Arctic environment, with potential not only to affect drinking water supplies, but also the local ecosystem and even microbial life on the ice. With increasing use of snowmobiles and helicopters in this region, evaluation of both the long and short term impacts of hydrocarbon pollutants must continue.

Brugger, K. A., (2007), The non-synchronous response of Rabots Glaciär and Storglaciären, northern Sweden, to recent climate change: a comparative study, Annals of Glaciology, 46, 275-282.

Clason, C.C., Coch, C., Jarsjö, J., Brugger, K., Jansson, P. & Rosqvist, G., (submitted), Dye tracing for investigating flow and transport properties of hydrocarbon-polluted Rabots glacier, Kebnekaise, Sweden, Hydrology and Earth System Sciences

Clason, C.C., Jarsjö, J., Rosqvist, G. & LaBianca, A., (in preparation), Glacier melt modelling and mass flux of hydrocarbon pollutants on Rabots Glacier, Kebnekaise