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Image of the Week – Cryo Connect presents: The top 50 media-covered cryosphere papers of 2018

Discover which cryospheric research articles were most successful in attracting media attention in 2018 according to the Altmetric score.


Cryo Connect and Altmetric

Scientists are generally aware of each others’ studies. But when a scientific study generates media interest, its impact can be boosted beyond the scientific community. The media can push the essence of scientific study to the broader public through newspapers and news websites, television and social media. It all counts, and Altmetric tracks mentions of scientific studies across many media outlets. 

Cryo Connect is all about boosting outreach communication in cryospheric sciences, and developing a joint AGU- and EGU-endorsed community outreach platform for cryospheric researchers. So we comb through Altmetric data each year to see which cryospheric studies are garnering top media coverage. Visit https://CryoConnect.net to learn how to help boost your cryospheric research, or simply tag @CryoConnect on Twitter.

The colors of the Altmetric badges represent the different types of media coverage.

Cryospheric Top 50

What does the top 3 look like?
A Nature study that developed a consensus estimate of the mass balance of the Antarctic Ice Sheet garnered the most attention of any cryosphere study in 2018. This study was authored by the 80-author “IMBIE”, or Ice Sheet Mass Balance Inter-comparison Exercise, team. The second most media-featured cryosphere study of 2018 was a Science Advances study, which described an impact crater beneath the Hiawatha Glacier in Northwest Greenland, by Kurt Kjaer and 22 colleagues. The third most media-featured study of 2018 was a Nature study that documented a non-linear increase in meltwater runoff from the Greenland Ice Sheet since the industrial revolution, by Luke Tusel and eight colleagues.

The five most popular scientific journals of the top-50 list are: Nature Communications (9 studies), Geophysical Research Letters (8 studies), Nature (6 studies), and Science Advances and Nature Geoscience (5 studies each). Together, these five journals published two-thirds of the 50-top cryospheric science studies. Perhaps interestingly, Nature Communications and Science Advances are both relatively new journals — both less than eight years old — that provide gold open-access venues. Both EGU (The Cryosphere) and AGU (Geophysical Research Letters) journals are featured on the top-50 list.

There is a notable year-on-year increase in Altmetric scores comprising the top-50 list. At the low end, the rank #50 cut-off Altmetric score increased from 201 in 2017 to 293 in the 2018 list presented here. At the high end, the rank #1 Altmetric score increased from 1330 in 2017 to 3379 in 2018. Overall, the average top-50 Altmetric score increased from 442 in 2017 to 744 in 2018. We used the same methodology, described below, to generate the 2017 and 2018 top-50 lists.

It is difficult to precisely explain this year-on-year increase in Altmetric scores within the cryospheric sciences. There could be an increasing trend in cryosphere science coverage in the media, or improved detection of media coverage by Altmetric, or perhaps 2018 just had an unusually strong batch of cryospheric studies published. In any case, we congratulate all the authors of 2018’s top media-covered cryospheric studies on the well-deserved media attention that they have received, and the exposure they have given to cryospheric science!

Rank Altmetric Score Publication title Journal
1 Mass balance of the Antarctic Ice Sheet from 1992 to 2017 Nature
2 A large impact crater beneath Hiawatha Glacier in northwest Greenland Science Advances
3 Nonlinear rise in Greenland runoff in response to post-industrial Arctic warming Nature
4 Viable nematodes from late Pleistocene permafrost of the Kolyma River Lowland, Doklady Biological Sciences
5 Arctic sea ice is an important temporal sink and means of transport for microplastic Nature Communications
6 Exposed subsurface ice sheets in the Martian mid-latitudes Science
7 Direct evidence of surface exposed water ice in the lunar polar regions Proceedings of the National Academy of Sciences
8 Warm Arctic episodes linked with increased frequency of extreme winter weather in the United States Nature Communications
9 Net retreat of Antarctic glacier grounding lines Nature Geoscience
10 The Greenland and Antarctic ice sheets under 1.5 °C global warming Nature Climate Change
11 Trends and connections across the Antarctic cryosphere Nature
12 Permafrost stores a globally significant amount of mercury Geophysical Research Letters
13 Near-surface environmentally forced changes in the Ross Ice Shelf observed with ambient seismic noise Geophysical Research Letters
14 Reduced probability of ice-free summers for 1.5 °C compared to 2 °C warming Nature Climate Change
15 21st-century modeled permafrost carbon emissions accelerated by abrupt thaw beneath lakes Nature Communications
16 Observed rapid bedrock uplift in Amundsen Sea Embayment promotes ice-sheet stability Science
17 Formation of metre-scale bladed roughness on Europa’s surface by ablation of ice Nature Geoscience
18 On the propagation of acoustic–gravity waves under elastic ice sheets Journal of Fluid Mechanics
19 The influence of Arctic amplification on mid-latitude summer circulation Nature Communications
20 Topographic steering of enhanced ice flow at the bottleneck between East and West Antarctica Geophysical Research Letters
21 Warming of the interior Arctic Ocean linked to sea ice losses at the basin margins Science Advances
22 Evidence of an active volcanic heat source beneath the Pine Island Glacier Nature Communications
23 Experimental evidence for superionic water ice using shock compression Nature Physics
24 Variation in rising limb of Colorado River snowmelt runoff hydrograph controlled by dust radiative forcing in snow Geophysical Research Letters
25 Vulnerability of Arctic marine mammals to vessel traffic in the increasingly ice-free Northwest Passage and Northern Sea Route Proceedings of the National Academy of Sciences
26 Stopping the flood: could we use targeted geoengineering to mitigate sea level rise? The Cryosphere
27 Limited influence of climate change mitigation on short-term glacier mass loss Nature Climate Change
28 Degrading permafrost puts Arctic infrastructure at risk by mid-century Nature Communications
29 Seismology gets under the skin of the Antarctic Ice Sheet Geophysical Research Letters
30 Dark zone of the Greenland Ice Sheet controlled by distributed biologically-active impurities Nature Communications
31 Freshening by glacial meltwater enhances melting of ice shelves and reduces formation of Antarctic Bottom Water Science Advances
32 Ice core records of west Greenland melt and climate forcing Geophysical Research Letters
33 Arctic warming hotspot in the northern Barents Sea linked to declining sea-ice import Nature Climate Change
34 Path-dependent reductions in CO2 emission budgets caused by permafrost carbon release Nature Geoscience
35 Discovery of a hypersaline subglacial lake complex beneath Devon Ice Cap, Canadian Arctic Science Advances
36 Cascading lake drainage on the Greenland Ice Sheet triggered by tensile shock and fracture Nature Communications
37 Global sea-level contribution from Arctic land ice: 1971–2017 Environmental Research Letters
38 Discovery of moganite in a lunar meteorite as a trace of H2O ice in the Moon’s regolith Science Advances
39 The world’s largest High Arctic lake responds rapidly to climate warming Nature Communications
40 Mass loss of Totten and Moscow University Glaciers, East Antarctica, using regionally optimized GRACE mascons Geophysical Research Letters
41 A 400-Year ice core melt layer record of summertime warming in the Alaska Range Journal of Geophysical Research: Atmospheres
42 What drives 20th century polar motion? Earth & Planetary Science Letters
43 Response of Pacific-sector Antarctic ice shelves to the El Niño/Southern Oscillation Nature Geoscience
44 Dynamic response of Antarctic Peninsula Ice Sheet to potential collapse of Larsen C and George VI ice shelves The Cryosphere
45 Increased West Antarctic and unchanged East Antarctic ice discharge over the last 7 years The Cryosphere
46 Change in future climate due to Antarctic meltwater Nature
47 Antarctic ice shelf disintegration triggered by sea ice loss and ocean swell Nature
48 Heterogeneous and rapid ice loss over the Patagonian Ice Fields revealed by CryoSat-2 swath radar altimetry Remote Sensing of Environment
49 Persistent polar ocean warming in a strategically geoengineered climate Nature Geoscience
50 Ice loss from the East Antarctic Ice Sheet during late Pleistocene interglacials Nature

Methodology

This top-50 cryospheric articles list was compiled using access to the Altmetric Explorer database provided by Altmetric. Similar to the 2017 top-50 list of cryospheric studies, we searched Altmetric Explorer for all peer-reviewed articles published between 1 January and 31 December 2018 that were within the field-of-research codes for Atmospheric Science (0401), Geochemistry (0402), Geology (0403), Geophysics (0404), Physical Geography and Environmental Science (0406), Environmental Science and Management (0502), Soil Sciences (0503) or Other Environmental Sciences (0599). We further limited qualifying articles to those with keywords of Antarctic, Arctic, Cryosphere, Firn, Frozen, Glacier, Glaciology, Ice, Iceberg, Permafrost, Polar and Snow.

The resulting articles were then ranked by Altmetric score. The Altmetric scores shown here are characteristic of 29 March 2019, and will tend to grow over time with subsequent media coverage. Please contact info@cryoconnect.net if you have questions about methodology or oversights.

This is a joint post, published together with Cryo Connect.

Edited by Sophie Berger and Violaine Coulon


Cryo Connect is an initiative run by Dirk van As, Faezeh Nick, William Colgan and Inka Koch.

Image of the Week – 5th Snow Science Winter School

The participants to the 5th Snow Science Winter School [Credit: Anna Kontu]

 

From February 17th to 23rd, 21 graduate students and postdoctorate researchers from around the world made their way to Hailuoto, a small island on the coast of Finland, to spend a week learning about snow on sea-ice for the 5th Snow Science Winter School. The course, jointly organized by the Finnish Meteorological Institute and the Swiss Federal Institute for Forest, Snow and Landscape Research WSL, brought together a wide range of scientists interested in snow: climate modellers, large-scale hydrologists, snow microstructure modellers, sea-ice scientists and remote sensing experts studying the Arctic, Antarctica and various mountain ranges. The week was spent between field sessions out on the sea-ice, daily lectures, and data analysis sessions, punctuated by amazing food and Finnish saunas to finish the day!


Field sessions

Our field sessions focused on learning to use both standard snow measurement techniques and advanced state-of-the-art methods. We first practiced sampling the thin, crusty snowpack with traditional methods: digging snow pits and recording grain size, temperature profile and density. We then moved to advanced techniques, learning about micro-tomography – which generates 3D images of the snow without destroying the way the individual ice crystals are arranged, near-infrared imagery and the measurement of specific surface area of the snow crystals by recording how a laser beam is reflected and modified as it passes through the snow sample.  These techniques all give information on how the snow crystals are arranged in the snow pack that are not obtainable with the traditional techniques. They also give important parameters for remote sensing validation and snowpack modelling.

The lecturers had brought with them some of the most advanced instruments, in some cases their own unique prototypes, giving us an amazing opportunity to practice working with these instruments. Amongst them was the SLF SnowMicroPen, which can measure the mechanical resistance of the snowpack, the optical sensors IRIS and SnowCube which use the reflection from a laser beam to calculate the surface area of the snow crystals, and a small radar which relates the conductivity of snow to the amount of liquid water mixed in with the snow and the density. On top of that, we honed our sea-ice drilling and measurement skills.  During our field sessions, we were exposed to all the conditions a field researcher might experience, from cloudy skies, over to high winds threatening to blow away all your equipment to crisp, cold blue skies.

The students braving the winds to collect data [Credit: Guillaume Couture]

Practicing snow crystal identification under blowing snow conditions [Credit: Anika Rohde].

Lectures

Our daily lectures covered a range of topics, leaning on the expertise of the instructors of the course. After a short introduction about sea-ice, a well-needed refresher considering the wide range of backgrounds of the participants, we jumped into snow-science. We learned about snow measurements from a field, remote sensing, and modelling perspective. The lectures sparked multiple discussions, from the continual need for more ground-validation for remote sensing data, over spatial representativeness and accuracy of the field samples to modelling approaches and a consideration of the limitations of the observational datasets.

Final projects

After learning how to use these fancy and expensive instruments and using our newly gained knowledge of snow on sea-ice, we were given a day to plan our own field session, collect data, analyze the results and present our result to the other groups on the final afternoon. Some very ambitious projects were quickly checked by reality in the field and the snow conditions were exceptionally challenging. This meant that our data might not perhaps yield any scientific breakthroughs in the field of snow science, but that we certainly learned how to adapt measurement and analysis designs on the fly and will hopefully all have an all-weather plan for the next expedition out into the snow for our various projects at home.

Calculating specific area with the SnowCube [Credit: Anika Rohde].

More than the science

On our second evening, we braved the elements for the ice breaker held in a tent on the sea ice. Luckily, only the ice between the students and lecturers broke so that everyone appeared again at breakfast the next day. The delicious food kept us warm for the duration of the trip and anyone still feeling cold could enjoy the sauna for a truly Finnish experience. Our knowledge gained over the week was tested on the final evening with a sea-ice themed trivia organized by the instructors.

Being this far north provides a great opportunity to witness some elusive northern lights.  During the entire week, we kept a close eye on the aurora borealis forecast, and we finally had a good chance of seeing them on our last night. Needless to say, we put our field gear back on to head outside and were rewarded by a beautiful display of dancing green and pink lights in the skies. A wonderful way to finish a successful week of learning, meeting fellow researchers and sparking new research questions!

The elusive northern lights appearing on our last night in Hailuoto [Credit: Anika Rohde]

The accommodation treated us to some beautiful sunsets! [Credit: Caroline Aubry-Wake]

To finish on a high not, here is a short video summarizing our incredible week in Hailuto! [Credit: Caroline Aubry-Wake]

Edited by Violaine Coulon


Caroline Aubry-Wake is a mountain hydrology PhD candidate at the University of Saskatchewan, Canada. By combining mountain fieldwork in the Canadian Rockies with advanced computer modelling, she aims to further understand how melting glaciers and a changing landscape will impact water resources in the future.

 

 

 

Maren Richter is a PhD student at the Department of Physics of the University of Otago. A physical oceanographer by training, she has turned her focus on the solid state of water to study ice-ocean interactions in Antarctica. Specifically, the effect of platelet ice formed near ice shelf cavities on landfast sea ice thickness evolution and variability on interannual to decadal timescales.

 

Image of the Week — Into Iceberg Alley

Tabular iceberg, Ross Sea, Antarctica [Credit: Marlo Garnsworthy]

Crew in hardhats and red safety gear bustle about, preparing our ship for departure. A whale spouts nearby in the Straits of Magellan, a fluke waving in brief salute, before it submerges again. Our international team of 29 scientists and 2 science communicators, led by co-Chief Scientists Mike Weber and Maureen Raymo, is boarding the JOIDES Resolution, a scientific drilling ship. We’re about to journey on this impressive research vessel into Antarctic waters known as Iceberg Alley for two months on Expedition 382 of the International Ocean Discovery Program.

Not only are these some of the roughest seas on the planet, it is also where most Antarctic icebergs meet their ultimate fate, melting in the warmer waters of the Antarctic Circumpolar Current (ACC), which races unimpeded around the vast continent. And there, in the Scotia Sea, we will drill deep into the sea floor to learn more about the history of the Antarctic Ice Sheet.


The Drilling Ship

The JOIDES Resolution, our scientific drilling ship [Credit: William Crawford and IODP]

The JOIDES Resolution is a 134-meter-long research vessel topped by a derrick towering 62 meters above the water line. It can drill hundreds of meters into the sea floor to retrieve long cylinders of mud called cores. Analyzing this sediment can tell scientists much about geology and Earth’s history, including the history of Climate Change.

“Sediment cores are like sedimentary tape recorders of Earth’s history,” says Maureen Raymo. “You can see how the climate has changed, how the plants have changed, how the temperatures have changed. Imagine you had a multilayer cake and a big straw, and you just stuck your straw into your cake and pulled it out. And that’s essentially what we do on the ocean floor.”

Our drilling sites in the Scotia Sea. [Figure modified from Weber, et al (2014)]

Our expedition is “going to a place that’s never really been studied before,” adds Maureen Raymo. “In fact, we don’t even know what the age of the sediment at the bottom will be.” Nevertheless, we hope to retrieve a few million years’ worth of sediment, perhaps even more. The sediment cores will provide a nearly continuous history of changes in melting of the Antarctic Ice Sheet.

What can these cores tell us?

As icebergs melt, the dust, dirt, and rocks they carry—known as “iceberg rafted debris”—fall down through the ocean and are deposited as sediment on the seafloor. Analyzing this sediment can tell us when the icebergs that deposited it calved from the ice sheet, and even where they came from. At times when more debris was deposited, we know more icebergs were breaking away from the Antarctic Ice Sheet, which tells us the ice sheet was less stable.

Much shorter cores previously collected at our drilling sites reveal high sedimentation rates, allowing us to observe changes in the ice sheet and the climate on short timescales (from just tens to hundreds of years).

We now know that rapid discharge of icebergs—caused by rapid melting of Antarctic ice shelves and glaciers—occurred in the past, and that episodes of massive iceberg discharge can happen abruptly, within decades. This has huge implications for how the Antarctic Ice Sheet may behave in the future as our world warms.

Where do icebergs come from?

Ok, let’s back up a little—back to where these icebergs were born. Icebergs break off or “calve” from the margins (edges) of ice shelves and glaciers. Ice shelves are floating sheets of ice around the edges of the land. They are important because they have a “buttressing” effect—that is, they act as a wall, holding back the ice behind them. Glaciers are great flowing rivers of ice that grind their way across the land, picking up the rocks and dirt that become iceberg-rafted debris.

Thwaites velocity map animation [Credit: Kevin Pluck, Pixel Movers & Maker]

Most Antarctic icebergs travel anti-clockwise around Antarctica and converge in the Weddell Sea, then drifting northward into the warmer waters of the Antarctic Circumpolar Current.

Iceberg flux 1976-2017  [Credit: Kevin Pluck & Marlo Garnsworthy, Pixel Movers & Makers]

As our planet warms due to our greenhouse gas emissions, warmer ocean currents are melting Antarctica’s massive glaciers from below, thinning, weakening, and destabilizing them. In fact, the rate of Antarctic ice mass loss has tripled over the last decade alone.

Polar researchers predict that global sea level will rise up to one meter (around 3.2 feet) by the end of this century, and most of this will be due to melting in Antarctica. And if vulnerable glaciers melt, the West Antarctic Ice Sheet is more likely to collapse, raising sea level even further.

Blue is old ice, Mc Murdo Sound, Antarctica [Credit: Marlo Garnsworthy]

 

A Hazardous Voyage

We face several hazards on this journey. We are hoping we won’t encounter sea ice, as our vessel is not ice-class, but it’s something we must watch for, especially later in the cruise as winter draws nearer. It is certain that, at times, we’ll experience a sea state not conducive to coring—or to doing much but swallowing sea-sickness medication and retiring to one’s bunk. In heave greater than 4–6 meters, operations must stop for the safety of the crew and equipment.

Of course, our highly experienced ice observer will be ever on the lookout for our greatest hazard—icebergs, of course! We are likely to encounter everything from very small “growlers” to larger “bergy bits” to massive tabular bergs. In fact, it is the smaller icebergs that present the most danger to the ship, as large icebergs are both visible to the eye and are tracked by radar, while smaller ones can be more difficult to detect, especially at night. Nevertheless, we are intentionally sailing into the area of highest iceberg concentration and melt.

“My hope,” says Mike Weber, “is that our expedition will unravel the mysteries of Antarctic ice-sheet dynamics for the past, and this may tell is something about its course in the near future.”

“Bergy bit”, Ross Sea, Antarctica [Credit: Marlo Garnsworthy]

Edited by Sophie Berger


The JOIDES Resolution is part of the International Ocean Discovery Program and is funded by the US National Science Foundation.

Marlo Garnsworthy is an author/illustrator, editor, science communicator, and Education and Outreach Officer for JOIDES Resolution Expedition 382 and previously NBP 17-02. She and Kevin Pluck are co-founders of science communication venture PixelMoversAndMakers.com, creator of the animations in this article.

Bridging the crevasse: working toward gender equity in the cryosphere

Figure 1: PhD student Gemma Brett conducts fieldwork examining variability in the distribution of the sub-ice platelet layer in McMurdo Sound, Antarctica [Credit: Florence Isaacs]

Today is International Women’s Day. As three early career glaciologists, we set out to investigate the state of gender diversity in the cryospheric sciences. Is there a better day for this than the day of recognition of the fight for women’s rights across the globe?


“The extreme nature of high alpine and polar environments made the rhetoric of mountaineering and glaciology heroic and masculine, which made both pursuits the embodiment of gentlemanly activity”
— Jaclyn R. Rushing
Women and Glaciers: Changing Dynamics in Sport, Science, and Climate Change

Descended from the earliest mountaineers and explorers, glaciology has been, like many sciences, long dominated by men. As today is International Women’s Day, we set out to understand gender diversity in the cryospheric sciences. With this blog post, we aim to provide two resources: 1) the most up-to-date statistics about gender in the cryospheric sciences and 2) a list of things that you can do to improve diversity in our beloved discipline.

As Lora Koenig and her co-writers succinctly stated:

If we value diversity and believe our discipline will be at its best when every student has equal opportunity, then we must do more than talk; we must act. Awareness and data collection are part of ensuring a diverse field now and in the future.”

Note: Our use of ‘women’ is intended to encompass all those who are female-identifying. The only statistics and research on this topic that were available at the time of writing lean heavily on the classification of individuals as ‘male’ or ‘female’. We wish to highlight that these sources exclude those of us with a gender identity that does not fit within this binary, and emphasise that we are speaking within these limitations in this article. Also, while this article focuses on research about women within academia, the experiences of women involved in knowledge-gathering outside this formal structure are varied and important.

The gender gap in science

According to the UNESCO Institute for Statistics, fewer than 30% of the world’s researchers are women, and women in STEM fields (Science, Technology, Engineering and Mathematics) “publish less, are paid less for their research and do not progress as far as men in their careers”.

Figure 2 shows data from our blog’s host, the European Geosciences Union (EGU) – all sections considered – for the past two years. Women currently account for one-third of all EGU members. On the other side of the Atlantic, the American Geophysical Union (AGU) has a slightly lower percentage of women — about 30% of all members in 2018.

Figure 2. Gender breakdown in EGU membership data – all sections considered – for 2018. The numbers presented are valid as of 08/03/2018. These numbers are estimates as they account only for active members who have filled out their membership profile. Members are not directly asked what gender they are, but they have been asked to select their salute (Mr vs Ms/Mrs), and self-designate as early-career. Emeritus members are members older than 60 or retired. Width is not to scale [Credit: Barbara Ferreira, EGU Media and Communications Manager].

How does the cryosphere compare?

We reviewed data from the American Geophysical Union (AGU) and the International Glaciological Society (IGS). Unfortunately, the EGU Cryosphere section has not yet published a breakdown of gender diversity (it’s on its way!).

Figure 3. Gender breakdown in AGU Cryosphere Sciences and International Glaciological Society membership data for all members in 2018 and by career stage in 2015. Circle size is not to scale [Credit: Lara Koenig for AGU data and Louise Buckingham, Doug MacAyeal, and Francisco Navarro for IGS data].

Similar to the overall gender breakdown, women make up 32% of all the AGU Cryosphere members in 2018 (Fig. 3). The IGS had a lower percentage: about 20% of its 670 members could be identified as women by name, although this was not self-reported and some members’ gender could not be discerned.

One significant trend that has been noted in previous posts on diversity in the cryosphere is that the gender imbalance is inversely proportional to career stage — more women are joining as students. A similar trend was recognized in 2015 AGU Cryosphere and IGS membership data (Figure 3) as well as in recent Australian data showing that in STEMM (STEM + Medicine), women make up half of postgraduate students!

However this trend cannot yet be seen in senior academic positions. There are two causes. One, a supply problem: women were historically excluded from the sciences (see below). Two, a filtering problem: the gender-filtered leaky pipeline” phenomenon describes how science progressively loses women as their scientific career evolves.

Many factors are responsible for women leaving the sciences. Awards, first authorships, and representation on boards and committees can play a big factor in whether scientists receive job offers or tenure. Do women receive nominations at a level at least proportional to representation? Data is limited on this front, but we have found that:

Like the UNESCO effort to follow and explore the careers of women in science, we urge AGU, EGU, IGS, and other Arctic and Antarctic institutions and communities to track the retention and acknowledgement of early-career women. We need to retain women, not just recruit them.

Barriers to access or the origins of the gender gap

A 2013 study published in Nature identified that “Despite improvements, female scientists continue to face discrimination, unequal pay, and funding disparities”. This study has been reproduced in all shades and flavors. Here is a non-exhaustive list of factors that could contribute to the underrepresentation of women in the cryospheric sciences (most of the following points apply to any scientific field of study):

  • Participating in conferences and presenting research is a mean of spreading scientific results, finding employment opportunities and funds, and obtaining awards and recognition. However, abstracts to conferences from male authors are more likely to be rated higher. It has also been shown that women were invited and assigned oral presentations less often than men for the AGU Fall Meetings, and also elect for poster presentations only more than men. White men are also more likely to receive a response from a potential PI despite identical resumes to a female applicant.
  • Fieldwork is associated with a lack of safety and inclusivity: women bear the brunt of harassment in science — half of all women in science have been sexually harassed, and in a recent study on 95 Australian women who conducted fieldwork in Antarctica, 63% — 60 women — reported being harassed or sexually harassed in the field. Of those, 47 felt unable to take any action. Women are more likely to be on the receiving end of microaggressions, which have long-lasting impact.  
  • Historical barriers to participation in polar field work: there are few well-known examples of female scientists in history, a result of women being unacknowledged for their scientific contributions (e.g. Julia Weertman, until recently) or barred from participating in research. For example, the British Antarctic Survey barred women until 1987, when they allowed Liz Morris to join an expedition. Glaciology has long been – and still remains, despite recent improvements – a male-dominated field.
  • Women are often the primary caregivers to children, family with mental illness, and aging parents or partners, on top of their work as researchers. Goulden et al. (2011) have shown that family formation like marriage and childbirth accounts for the largest leaks in the “pipeline” in the sciences. They also underline the limited benefits (such as paid maternity and parental leave) that are offered to scientists. As a consequence, in the US, nearly half of female scientists leave full-time science after their first child.
  • The outdoor industry continues to be male dominated, e.g. in guiding careers, meaning that women are more likely to experience barriers to access. Outdoor gear and tools, including gear provided by the U.S. Antarctic Program, are exclusively or heavily fit for men, making fieldwork more difficult and often more dangerous for women. New Zealand is one of the only countries that has women-specific polar clothing.

What can we do?

So what’s the state of gender in the cryosphere? We are making progress. Indeed, the gender balance in the cryosphere is improving:

  • Hulbe et al. [2010] documented the sex of first and second authors in International Glaciological Society journals from 1948 to 2010. Female authors comprised about 5% of authors from the 1950s through the 1980s, 13% in the 1990s, 16% in the 2000s, and roughly 20% by the end of the study.
  • An analysis of IGS memberships numbers indicates that the proportion of female members has increased over time.
  • The percentage of women in the American Geophysical Union Cryosphere section rose from around 26% in 2013 to about 32% in 2018.

As early career scientists, this is heartening — the efforts to improve gender diversity are working. We, as early-career women, stand not just on the shoulders of the pioneering women that opened the door, but of a whole community reckoning with its biases. The thing we’re most often asked is What can I (as a male PI, as an institutional leader, as a PhD student organizing seminars) do?”. The figures below gather a few ideas about where to start. Please comment with your own! Of course, these also apply to the broader spectrum of physical sciences and academia.

Fixing gender imbalance in the cryosphere [Credit: Florence Isaacs, Elizabeth Case and Violaine Coulon]

Conclusion

With this post, we hope to open discussions about gender diversity in the cryospheric sciences, how it’s changing (for the better), and what you can do to help increase diversity. Others have written recently and extensively about this, including Christina Hulbe, Lora Koenig, and others. We have put together a list of some of these resources below. We will continue to update this, so please let us know if there is something that needs to be added.

We also want to acknowledge the severe lack of racial and ethnic diversity, and a lack of research on the experiences of queer and disabled people in the geosciences. Where we have made strides for some women, we have left behind many others…

Further resources

Edited by Clara Burgard


Violaine Coulon is a PhD student of the glaciology unit, at the Université libre de Bruxelles (ULB), Brussels, Belgium. She is using a numerical ice sheet model to investigate the dynamics and stability of the Antarctic Ice Sheet for the past 1.5 million years. She also investigates the sensitivity of the Antarctic Ice Sheet to the incorporation of lateral variability in the viscoelastic Earth structure across Antarctica.

 

 

Florence Isaacs is a PhD student at Victoria University of Wellington’s Antarctic Research Centre, New Zealand. Her current research examines the relationship between Southern Hemisphere climate variability, sea ice, and the East Antarctic Ice Sheet. She is passionate about increasing diversity in science, and tweets at @flisaacs.

 

 

 

Elizabeth Case is a PhD student at Columbia University and the Lamont-Doherty Earth Observatory investigating ice deformation through radar and modelling. She rode her bike across the country in 2015 as a co-founder of Cycle for Science, and continues to advocate for adventure-based science education. You can find her @elizabeth_case.

 

The hidden part of the cryosphere – Ice in caves

The hidden part of the cryosphere – Ice in caves

The cryosphere can be found in various places in many forms and shapes… in the atmosphere, on land and sea. A lesser known part of the cryosphere is hidden deep in the dark, in the cold-karstic areas of the planet: Ice caves! The ongoing climate change affecting ice all over the world is now rapidly melting these hidden ice masses as well. We therefore need to hurry up and try to collect as much information as we can before all will melt away…


The big melting

The ice masses around the globe, in ice sheets, sea ice, and mountain glaciers, have been melting away in past decades (see this previous post). The reduction of the cryosphere, both in terms of area and mass, has particularly been visible in the European Alps over the last 30 years. On the one hand, large and small Alpine glaciers decline, fragment and even disappear, and this trend has accelerated since the mid 1980s. Mountain glaciers are therefore considered to be sensitive indicators for climate variability. On the other hand, the warming climate is also acting on permafrost degradation, mostly affecting the stability of rock-slopes and cliffs.

What makes the international scientific community worry at the moment is how fast this abrupt glacial reduction is occurring globally. However, not all the natural environments respond in the same way to sudden changes in the climate system! Fortunately for us scientists, there are physical environments and ecological niches more resilient to external perturbations. This aspect has sometimes allowed the preservation of environments and information in the Earth’s climatic history that would have been otherwise destroyed.

Caves are resilient

Among the most resilient natural environments there are caves, “protected” by the rocky mass within which they were formed. In the mountains, high-altitude karst cavities can contain huge deposits of ice representing a lesser known part of the cryosphere. Speleologists face such ice in caves both as a joy and a damnation: fascinating by their beautiful shapes and morphologies, they also see it as an unwieldy presence that prevents explorations of still unknown voids in the alpine karstic systems.

Fig. 2: An ice deposit in a cave of the southeastern Alps [Credit: Renato R. Colucci].

 

But ice in caves is not just something beautiful (but isn’t it? Look at Fig. 2!). It rather represents a precious natural archive, sometimes with high temporal resolution, able to tell the climate history of large part of the Holocene (the last 11700 years of the Earth’s history). The permanent ice deposits, i.e. the ice staying longer than just a winter season, often defined in a colorful way as “fossil ice” by speleologists, is what counts the most. As it typically gets older than 2 years, which is one threshold for the general definition of permafrost, this phenomenon is part of the mountain permafrost… right or wrong, ice in caves is ground ice!

Fig. 3: Huge entrance of a cave opening in the Dachstein limestones of the Canin-Kanin massif, southeastern Alps [Credit: Renato R. Colucci].

 

Generally in the Alps such ice deposits lie in caves having their opening at altitudes above 1,000 m (Fig. 3), but locally even lower. The formation of these unique environments depends on a combination of geomorphological and climatic characteristics, which allow for accumulation and preservation of ice also in places where this would be very unlikely.

Now, although the caves are resilient environments, ice melting due to climate change is rapidly increasing there as well. This is why it is important to save as much information as possible from the remaining ice, before it is definitely lost!

The C3 project – Cave’s Cryosphere and Climate

The C3-Cave’s Cryosphere and Climate project is under the scientific guidance of the National Research Council (CNR) of Italy, and precisely the climate and paleoclimate research group of ISMAR Trieste. It aims to monitor and study ice deposits in caves. Such ice deposits store several information related to the paleoclimate, the biology, the chemistry and ecology of these environments.

Fig. 4: Drilling ice cores with the aim to extract the CCC layer from this ice body in a cave of the southeastern Alps [Credit: Arianna Peron].

The project started in 2016, following the discovery of a coarse cryogenic calcite deposit (CCCcoarse) in an ice layer (in-situ) in a cave of the Canin-Kanin massif, in the Julian Alps, located between Italy and Slovenia. This finding, representing the first evidence of CCC in the southern Alps, provides an important opportunity to understand the processes associated to the formation of these particular calcite crystals (Fig. 4). Previously, the CCC (Fig. 5) was only found on the floor in caves where ice had already melted away. What makes it interesting is the fact that it is possible to date these crystals using the isotopic ratio of some trace elements in radioactive materials, typically Uran and Thorium.

Fig. 5: Millimetric crystals of coarse cryogenic calcite found in-situ in the southern Alps [Credit: Renato R. Colucci].

The strongest financial and logistic support to the project is given by the Alpine Society of the Julian Alps through its speleological group, the E. Boegan Cave Commission. In addition to the CNR and other Italian institutions such as the University of Trieste, University of Bologna, Insubria University in Varese, Milano Bicocca University and the Natural Park of the Julian Prealps, the project involves research institutes and universities from Germany (Institute of Physics of Heidelberg University), Switzerland (Paul Scherrer Institut; Swiss Institute for Speleology and Karst Studies), Austria (Innsbruck University; Palynology and Archaeobotany Research Group), and Slovenia (Geological survey of Slovenia).

Many activities and several results already unveiled few of the secrets hidden in such environments: the realization of the first thermo-fluido-dynamic model in an ice cave, the development of innovative techniques for studying the mass balance of the ice, the study of the thermal characteristics of the rock and therefore of the permafrost and the active layer, the development of innovative and multidisciplinary methods of ice dating.

But there is little time to do all, and we must exploit it to the fullest!

Further reading

Edited by Clara Burgard


Renato R. Colucci works in the climate and paleoclimate research group of ISMAR-CNR, Department of Earth System Sciences and Environmental Technology. He is also adjunct Professor of glaciology at the University of Trieste (Italy). During his PhD he honed his skills in glacial and periglacial geomorphology at UNIS (University Center in Svalbard). His research centers around the interactions between cryosphere (glaciers, permafrost, ice caves) and the climate, spanning from the end of the Last Glacial Maximum to the present days.

Image of the Week – When “Ice, Ice Baby” puts rocks “Under Pressure”

Image 1: Composite image of the Aiguille Verte, the heavily-fractured headwall of the Glacier d’Argentière near Chamonix, France [Credit: D. Dennis].

Bowie and Queen said it first, and Vanilla Ice brought it back. But now, I’ve set out to quantify it: Pressure. Rocks in glacial landscapes can experience many different kinds of pressure (forces), from sources like regional tectonics or even the weight of the glacier itself. Our hypothesis is that smaller-scale pressures, caused by the formation of ice in small bedrock cracks (frost-weathering), have a large effect on the sculpting of landscapes in cold regions. This post will share how we evaluate these processes and their dependence on temperature, as well as discussing the broader effects for glacier and glacial landscape evolution.


Walking through the valley in the shadow of glaciers

Growing up just outside Glacier National Park, USA, at nearly the exact edge of the former Laurentide Ice Sheet, I became familiar with the romantic lore of how we understand glacial landscapes (Images 2, 3). Observing these glacial landscapes later throughout my formal Earth science education, I came to understand mountains as passive resistors to the relentless efficiency of glacier advance, erosion, and retreat—offering evidence of past glaciations but nonetheless devoid of agency in the rise and fall of icy stadials.

My current PhD research, however, investigates a slightly-modified premise: that glaciers and their landscapes respond in concert with climate, and that dividing the dynamics governing the ice and the rock may not be as straightforward as once thought. My work is a sub-project of the Climate Sensitivity of Glacial Landscape Dynamics (COLD) project, funded by the European Research Council (ERC) and lead by Dirk Scherler at the Deutches GeoForschungsZentrum (GFZ) in Potsdam, Germany.

Image 2: The author on holiday in Glacier National Park, Montana, circa 2001, demonstrating an early aptitude for glacial geomorphology and cosmogenic nuclide geochemistry. His affinity for popular German footwear at a young age foreshadowed his eventual move to Germany to study glaciology and geomorphology [Credit: D. Dennis].

Image 3: This image of Chamonix Valley and the M. Blanc massif conceptually outlines how average annual temperature may change with elevation in steep hillslopes. The highest peaks in the massif tower up to nearly 4000 m over Chamonix Valley, which sits at appx.1000m. This corresponds to a nearly ~20 °C difference in annual average temperature. [Image adapted from Google Earth].

Temperature as a control in glacial landscapes

Glaciers exist in locations with temperatures that are, for some portion of the year, below freezing, as this is a condition required for snow to persist through the melt season and to form ice. Temperature is therefore an important primary control on the stability of glaciers. These cold temperatures, however, impact mountain environments beyond just the formation/decline of glaciers, and several decades of recent research have shown that temperature is an important controlling factor on the type and magnitude of erosion (the act of dislodging and transporting rock) in cold landscapes.

Mountain glacier valleys are commonly characterized by steep head- and sidewalls which frame the glacier within (like in our Image of the Week). At our field sites in the French, Swiss, and Italian Alps, these rockwalls can tower up to 1500 m above the surface of the glaciers, corresponding to a temperature gradient of ~10 degrees (Image 3). Therefore, the rocks at different elevations are exposed to different temperature conditions, which could lead to differences in the rate of erosion.

Image 4: Permafrost degradation and frost-weathering in the steep hillslopes of the M. Blanc massif commonly lead to the deposition of debris on the glaciers at the base of the mountains. Shown here is Glacier d’Argentière (France) with patches of surface debris [Credit: D. Dennis].

Erosion in steep rockwall faces

Frost-weathering processes occur only at temperatures at or below zero, therefore requiring the same cold temperature conditions that form glaciers. At these temperatures, liquid water present in small cracks in the bedrock freezes. The pressure exerted on the rock by the ice as it freezes causes the rock to fracture, leading to large cracks in the bedrock (Image 5). Erosion occurs when the ice in the crack becomes large enough and its corresponding fracture wide enough that the rock can no longer remain attached and it falls from the rockwall surface.

Erosion can also occur when the ice in the crack melts and no longer “cements” the surface together. Because temperatures in glacial landscapes are commonly quite cold, much of the bedrock is considered permafrost (permanently-frozen ground), and remains frozen throughout the year. In the Alps, however, warmer temperatures over the past decades have caused the permafrost to thaw, melting the lenses of ice and causing larger and more frequent rockfalls.

Temperature conditions are therefore important for both the rate at which cracks form in rocks (and erode from the surface) in addition to permafrost stability and the size/frequency of rockfalls. As temperatures change in mountain regions due to global warming, this could lead to considerable changes in debris production.

Image 5: A cropped version of our Image of the Week, showing the base of the Aiguille Verte, headwall of Glacier d’Argentière. Large fractures in the bedrock are clearly visible. These may have grown from much smaller cracks that formed due to frost-weathering.

The hillslope/glacier surface connection

After material erodes from the surface of the headwall, it is often deposited onto the surface of the glacier (Image 3). As mentioned above, the deposition of material can occur both at a constant rate or sporadically (as in the case of permafrost-thaw rockfalls), depending on the controlling process. As such, determining the actual representative rate at which these headwalls erode is challenging.

Though this work can be complicated, we believe it to be important, as debris deposited on the surface of glaciers can insulate the ice from the effects of temperature (Image 4, Video 1). Though the global distribution of debris-covered glaciers is much smaller than debris-free glaciers, debris-covered glaciers make up a non-trivial fraction of the glaciers in populated mountain regions where they may be important fresh water sources, contribute to glacial hazards, or allow for the generation of hydropower. Understanding the supply of debris to these glaciers (via erosion), and how it may change, is therefore an important component of forecasting their evolution under warming climates.

Video 1: This drone footage from the Arolla Glacier, Switzerland, shows the steep relief which can develop as a result of differential melting. Debris thicker than 2-4 cm insulate ice, leading to topographic relief on the glacier surface as exposed ice melts and covered ice is protected. [Credit: D. Gök, GFZ]

Re-evaluating the dynamic glacial landscape

Though studies of frost-cracking and debris-covered glaciers individually are not necessarily brand new inventions, our methods for combining the two are rather novel. In doing so, we are linking the evolution of glacier with the evolution of the landscape itself, and investigating an interesting feedback loop induced by changes in climate. Should erosion rates increase with warmer temperatures, and the mountains therefore supply more debris to glacier surfaces, this could extend the “lifetime” of the glacier by insulating it; likewise, if erosion rates decrease, less debris supplied to already-covered glaciers could lead to less insulation and (comparatively) higher melt rates. This interplay demonstrates the complexity of Earth system processes, and the need to take these complexities into account when considering the effects of climate changes.

To summarize

Pressure, pushing down on rock,
Pushing laterally against rock, can cause them to fall.
Under (thick) debris, glacier melt will slow,
Despite higher temperatures,
And global warming.

Will it ever stop? I don’t know.
Turn up the temperatures, then no more (ice and) snow.
At the end of the day, frost-weathering needs ice,
When water can’t freeze, ice-cracking’s no dice.

Edited by David Docquier


Donovan Dennis is a PhD student at the Deutches GeoForschungsZentrum in Potsdam, Germany. He is interested in many aspects of glaciology and glacial geomorphology, and currently investigates the geomorphic feedbacks on glacial landscape erosion. He previously worked on post-deposition alteration of stable water isotope signals in snow and ice. He tweets as @donovan__dennis.

Contact Email: dennis@gfz-potsdam.de

 

Image of the Week – Seven weeks in Antarctica [and how to study its surface mass balance]

Figure 1 – Drone picture of our field camp in the Princess Ragnhild coastal region, East Antarctica. [Credit: Nander Wever]

After only two months of PhD at the Laboratoire de Glaciologie of the Université libre de Bruxelles (ULB, Belgium), I had the chance to participate in an ice core drilling campaign in the Princess Ragnhild coastal region, East Antarctica, during seven weeks in December 2018 – January 2019 for the Mass2Ant project. Our goal was to collect ice cores to better evaluate the evolution of the surface mass balance in the Antarctic Ice sheet. Despite the sometimes-uncomfortable weather conditions, the ins and outs of the fieldwork and the absence of friends and family, these seven weeks in Antarctica were a wonderful experience…


Mass2Ant

Mass2Ant is the acronym of the project: “East Antarctic surface mass balance in the Anthropocene: observations and multiscale modelling”. This project aims to better understand the processes controlling the surface mass balance in East Antarctica, its variability in the recent past and, ultimately, improve the projections of mass balance changes of the East Antarctic ice sheet.

What exactly is the surface mass balance?

The mass balance of an ice sheet (see Fig. 2) is the net balance between the mass gained by snow accumulation and the loss of mass by melting (either at the surface or under the floating ice shelves) and calving (breaking off of icebergs at the ice shelves fronts).

The surface mass balance on the other hand only considers the surface of the ice sheet. It is thus, for a given location, the difference between:

  • incoming mass: snowfall, and
  • outgoing mass, due to melting processes (fusion and sublimation), meltwater runoff and transport or erosion by wind at the ice sheet interface.

Figure 2 – Representation of the mass balance of an ice sheet [Credit: Figure adapted from NASA, Wikimedia Commons].

Overall, the ice sheet mass balance – the principal indicator of the “health state” of an ice sheet – is the balance between the surface mass balance, iceberg calving and basal melt under the ice shelves. A good evaluation of these three factors is thus essential to better quantify the evolution of the Antarctic mass balance under anthropogenic warming and therefore its contribution to future sea level rise.

However, the surface mass balance is characterized by strong temporal and spatial variations (see Figure 3) and is poorly constrained. In order to improve future projections for Antarctica, it is essential to better assess the variability of the Antarctic surface mass balance by directly collecting data in the field. Within this framework, the goal of the Mass2Ant project is to study the surface mass balance in the Princess Ragnhild coastal region (marked in the Figure 3).

Figure 3 – Surface mass balance (1989-2009) from RACMO2 (a regional climate model) of Antarctica (left) and Greenland (right) in kg/m².yr. Contour levels (dashed) are shown every 500 m. Black dot is the approximative position of the drilling site on the Tison Ice Rise. [Credit: adapted from Figure 1 of van den Broeke et al. (2011)].

Collecting the data [or how can we use ice cores to infer surface mass balance?]

Surface mass balance can be determined by analyzing ice core records. As a part of our expedition, ice cores were collected on the summit of the so-called “Tison Ice Rise” (a non-official name) – 70°S 21°E, near the Belgian Princess Elisabeth Station. We drilled to a depth of 260.1 m, which we expect to date back to the 15th century.
The drilling system, named the Eclipse drill, contains a motor on top of a drill barrel – which is composed of an inner barrel that cuts the ice core with 3 knives and collects it and an outer barrel (a tube) that collects the chips created. Due to the overlaying ice, pressure increases very quickly with depth. Deep ice cores are thus subject to much higher pressure than the atmospheric pressure. In order to reduce these strong pressure differences as the ice core is brought to the surface, drilling fluid was poured in the boreholes, a technique called “wet-drilling”. This was the first time the wet-drilling technique was used by our team, and it significantly improved the quality of our ice cores compared to the traditional method used during the previous campaigns!

Figure 4 – A part of our team in the drilling tent. An ice core can be observed in the inner barrel of the drilling system. A wooden box is placed on top of the trench, under the drill barrel to collect the chips contained in the outer barrel. [Credit: Hugues Goosse]

The 329 collected ice cores will be analyzed in our lab in Brussels. More specifically, we will focus on

  • the water stable isotopes: the seasonal cycle of stable isotopes of water in ice will be used for relative dating of the ice core;
  • the major ions (Na+, nssSO4, Na+/SO42-, NO3…) present in the ice: the reconstruction of the seasonal cycle of these ions allows us to refine the isotopic dating and therefore infer the annual snow/firn/ice thickness.
  • the conductivity of the ice, which also shows a clear seasonal signal used for dating. Moreover, the conductivity signal is also reacting to localized extra inputs – for example from past volcanic eruptions – therefore providing an absolute dating, which reduces our dating method uncertainties.

The seasonality of these signals will allow us to infer the yearly ice thicknesses (see this post). By taking into account the deformation of the ice, we will then be able to reconstruct the evolution of the surface mass balance in the Princess Ragnhild Coast region since the 15th century.

Life in the field

What was a typical day like for us? In fact, it strongly depended on the team to which you belonged as we were divided into two groups:

  • The “day group” was working on measurements such as snow density and radar analyses and worked roughly between 8 AM and 8 PM.
  • The second group – the drilling team, including me – worked during nights (between 9 PM and 9 AM) because of the too high temperatures during day, which would lead to ice core melt.

The drilling team adapted quite easily to this timing as the sun was shining 24 hours a day. In order to spend a common moment, a joint meal was organized every day at 8.30 AM, with some of us having their dinner while others were having breakfast.
The everyday life mainly occurred in two equipped containers. The first container was our living space, which we used as kitchen, dining room and working space. The second container consisted of a cloakroom, the toilets and the bathroom (with a real shower, a luxury in the field!). Each of us had a tent to sleep, with adapted sleeping bag, making it quite comfortable. As we stayed 5 weeks at the drilling site, we spent Christmas and New Year’s Eve on the field. It was a good occasion to eat fondue while sharing some fun stories and jokes (Fig. 5).

Figure 5 – Christmas time spent together, giving presents and eating fondue. [Credit: Nander Wever]

Why should you too go to Antarctica?

I’ll keep many memories of the time we all spent together, but also of the amazing landscapes and the calm and peacefulness of this white immensity… Despite the sometimes-uncomfortable weather conditions (a full week of whiteout days, lucky us!), this unique experience was wonderful! I’ve learned so much, from a scientific but also personal point of view. It was also a chance to participate in the collection of the samples that I will study during the next four years of my PhD. Before I left for Antarctica, someone told me that “When you went to Antarctica once, you usually want to go again”. Well, that’s definitely true for me!

Many thanks to belspo for funding this project, to the International Polar Foundation and Princess Elisabeth Antarctica staffs for the work both in Cape Town and in the station, and last but not least, thanks to the Mass2Ant team in the field that made this experience an amazing adventure.

Further reading

Edited by Violaine Coulon


Sarah Wauthy is a PhD student at Laboratoire de Glaciologie, Université Libre de Bruxelles, Belgium. Her PhD is part of the Mass2Ant project and aims at determining paleo-accumulation in the region of the Princess Ragnhild Coast (Dronning Maud Land, East Antarctica) as well as the paleo-extension of sea ice before and across the Anthropocene transition (ca. last 3 centuries), by performing high-resolution multiparametric analyses on ice cores collected during field campaigns.

Image of the Week – We walked the Talk to Everest

Fig. 1: Group photo with Mount Everest backdrop following presentations at the Sagarmatha National Park office in Namche Bazar (3,500 m a.s.l) with 60 participants (wrapped up against the cold temperatures). [Credit: Dhananjay Regmi].

The 12 day “Walk the Talk” Field Conference and Community Consultation through Sagarmatha National Park, Nepal, discussed a wide range of research outputs with local communities, tourists, and officials. Topics covered glaciers, mountains, environmental and landscape change, Sherpa livelihoods, tourism, and natural hazards. The conference, organised by Himalayan Research Expeditions, was the first of its kind, designed to receive community input into research topics and pursue applied benefits. Scott and Katie were two of the participants, presenting work from their PhDs in the Everest region and the NERC-funded EverDrill project.


Presentations and discussions

The team of international and Nepali scientists gave presentations every evening, trekking each day between six different villages along the Everest Base Camp trail. We were also joined by officials from the Nepal Department of Tourism and the Mountain Institute. The highest destination for the conference was Imja Glacial Lake, at over 5,000 m elevation, where we viewed first-hand the results of a recent $7 million project to lower the lake water level, aiming to reduce the risk of an outburst flood.

The Sagarmatha National Park has been a focus for scientists of many disciplines for decades. As well as thousands of tourists trekking to Everest Base Camp each year, it is also frequented by those hoping to summit Mount Everest (Sagarmatha). The park has therefore experienced significant change over a relatively short timescale as it copes with this huge influx of people. Presentations for the “Walk the Talk” conference ranged from impacts of tourism (for example, on local people, yak breeding and waste disposal) to natural hazards such as glacial lake outburst floods and landslides.

Katie presented ongoing work from her PhD and the “EverDrill” project (Fig. 2), for which she has conducted several field seasons on Khumbu Glacier in the Sagarmatha National Park. Fieldwork has included hot-water drilling of boreholes into the glacier and installing sensors to measure ice temperature at various depths to investigate the glacier’s thermal regime. She discussed how these measurements showed that Khumbu’s ice is warmer than expected, potentially putting the glacier at risk of more rapid melting as air temperatures rise. The warmer ice towards the terminus also allows subsurface meltwater drainage, about which very little is known. Katie has also carried out fluorescent dye tracing experiments to work out how meltwater travels through Khumbu Glacier, including storage within (englacial) and on the surface (supraglacial). As Khumbu and similar glaciers retreat in the future, meltwater storage and runoff will have implications for the downstream communities who depend on such water sources.

Fig. 2: Katie presenting measurements of Khumbu Glacier’s thermal regime and hydrology at the Sagarmatha National Park headquarters in Namche Bazar (3,500 m a.s.l.). [Credit: Dhananjay Regmi].

Scott presented results from his PhD investigating melt processes and water storage on Khumbu Glacier (Fig. 3). Areas of Khumbu Glacier have thinned by up to 80 m over the last three decades and glacier flow is slowing down, which allows meltwater to pond on the glacier surface. The rugged glacier surface is pitted with ice cliffs and ponds, which act as hot-spots of melt in areas of the glacier otherwise insulated by a thick layer of rocks and sediment (debris-cover). The rapid formation, persistence, and drainage of meltwater stored on glaciers across the Himalaya is a growing concern due to the potential for outburst floods and increased rates of glacier melt. An outburst flood event that occurred in the Everest region in 2017 destroyed trekking trails and a bridge.

Fig. 3: Scott presenting a study of glacier thinning at the Sagarmatha National Park office in Namche Bazar (3,500 m a.s.l). [Credit: Dhananjay Regmi].

After the final day of trekking, an extra night was spent in the village of Lukla, before flying back to Kathmandu. Each presentation was summarised in a few slides, and collated into a full talk that was given in Nepali by Dr. Dhananjay Regmi, organiser of the conference and head of Himalayan Research Expeditions. By presenting all our research in Nepali, more local people attended and were able to hear about and suggest new directions for research in the valley. This presentation was given again two days later, also in Nepali, at the Department of Tourism in Kathmandu, for locals who had already travelled back to the city to avoid the high-elevation winter chill.

Outreach activities

Fig. 4: The projection augmented relief model shown after presentations in the village of Phortse. The inset shows glacier velocity data projected onto the glaciers in the Everest region. [Credit: Gu Changjun and Scott Watson].

We designed outreach activities and leaflets to enhance the PowerPoint presentations given at each village by providing interactive demonstrations of key research concepts and results. Scott used an AGU Celebrate 100 grant to design a projection augmented relief model (PARM) of the Everest region (Fig. 4). The PARM system projected research results including glacier velocity, mass loss, ice thickness, temperature, and animations of glacier flow, onto a 3D model, which stimulated discussion of the research. The 3D model allowed the local communities to easily visualise the data in the context of well-known mountain peaks and glaciers, and to observe the changing environment (such as the expansion of Imja Lake) from a projected time-lapse animation.

Fig. 5: Katie demonstrating glacier thermal regime and hydrology using a 3D model to conduct example dye tracing experiments. The lower panel is a GIF showing the dye tracing. [Credit: Scott Watson and Katie Miles].

Katie’s interactive outreach was to demonstrate dye tracing experiments on a 3D model of Khumbu Glacier (Fig. 5). Food colouring was used to “dye” the water, which was “injected” into a supraglacial stream, then “disappeared” into the glacier. The side view into the glacier showed this water flowing through and beneath the ice, before emerging back at the surface, flowing through surface ponds and exiting the glacier at its terminus. The side view also showed the approximate ice temperatures measured by the EverDrill project, which actively showed where (and why) the glacier is experiencing more melt.

The model was very well received by scientists and locals – while the water was being injected, we would explain what was happening in both English and Nepali, and there were always plenty of questions. While the dye tracing experiments didn’t work perfectly every time, surface floods offered an opportunity to talk about other hazards that have been recently observed on Khumbu Glacier.

Summary

The “Walk the Talk” Field Conference and Community Consultation was a new style of conference, aiming to communicate a wide range of research topics in the Everest region of Nepal and the Sagarmatha National Park. The combination of high-elevation trekking and presentations was sometimes tiring, but the trek facilitated discussions about the landscape we were immersed in and was a fantastic learning experience. It is hoped that the conference will travel to different locations in the future to share research and understand the priorities of other communities in Nepal.

Further reading

Edited by Violaine Coulon


Scott Watson is a Postdoc at the University of Arizona, USA, studying glaciers in the Everest region and the surface interactions of supraglacial ponds and ice cliffs. He also investigates natural hazards and glacial lake outburst floods. Tweets @CScottWatson. Website: www.rockyglaciers.co.uk

 

 

 

Katie Miles is a PhD student at the Centre for Glaciology, Aberystwyth University, UK, studying the internal structure and subsurface hydrology of high-elevation debris-covered glaciers in the Himalaya through borehole-based investigations and dye tracing experiments. Tweets @Katie_Miles_851. EverDrill website: www.EverDrill.org

Image of the Week – Delaying the flood with glacial geoengineering

Figure 1: Three examples of glacial geoengineering techniques to mitigate sea-level rise from ice-sheet melting [Credit: Adapted from Figure 1 of Moore et al. (2018); Design: Claire Welsh/Nature].

As the climate is currently warming, many countries and cities are preparing to cope with one of its major impacts, namely sea-level rise. Up to now, the mitigation of climate change has mainly focused on the reduction of greenhouse gas emissions. Large-scale geoengineering has also been proposed to remove carbon from the atmosphere or inject aerosols into the stratosphere to limit the rise in temperature. But locally-targeted geoengineering techniques could also provide a way to avoid some of the worst impacts, like the sea-level rise. In this Image of the Week, we present examples of such a technique that could be applied to the Antarctic and Greenland ice sheets (Moore et al., 2018; Wolovick and Moore, 2018).


Sea level is rising…

The sea level of the world oceans has been rising at a mean rate of 3 mm per year since the 1990s, mainly due to ocean thermal expansion, land-ice melting and changes in freshwater storage (see this post). More than 90% of coastal areas could experience a sea-level rise exceeding 20 cm with a 2°C warming (relative to the pre-industrial period), which is likely to happen by the middle of this century (Jevrejeva et al., 2016).

The Antarctic and Greenland ice sheets constitute two huge reservoirs of ice and contain the equivalent of 60 and 7 m of sea-level rise, respectively, if completely melted. Although a complete disintegration of these two ice sheets is not on the agenda in the coming years, surface melting of the Greenland ice sheet and the flow of some major polar glaciers could be enhanced by different positive feedbacks (see this post on climate feedbacks and this post on marine ice sheet instability). These feedbacks would elevate the sea level even more than projected by the models.

… but could potentially be delayed by glacial geoengineering

In order to cope with this threat, reducing our greenhouse gas emissions might not be sufficient to delay the rise of sea level. One alternative has been suggested by Moore et al. (2018) and consists of using glacial geoengineering techniques in the vicinity of fast-flowing glaciers of the Antarctic and Greenland ice sheets. They propose three different ways to delay sea-level rise from these glaciers and these are presented in our Image of the Week (Fig. 1):

A.   A pumping station could be installed at the top of the glacier with the aim of extracting or freezing the water at the glacier base. This would slow down the glacier sliding on the bedrock and reduce its contribution to sea-level rise.

B.   An artificial island (about 300 m high) could be built in the cavity under the floating section of the glacier (or ice shelf). This would enhance the so-called buttressing effect (see this post) and decrease the glacier flow to the ocean.

C.   A wall of up to 100 m high could be built in the ocean bay right in the front of the ice shelf. This would block (partially or completely) any warm water circulating underneath the ice shelf and delay the sub-shelf melting (see this post).

In theory

Wolovick and Moore (2018) studied in detail the possibility of building artificial islands (proposal B above) underneath the ice shelf of Thwaites Glacier (West Antarctica), one of the largest glacier contributors to the ongoing sea-level rise. They used a simple ice-flow model coupled to a simple ocean model and considered different warming scenarios in which they introduced an artificial island underneath the ice shelf.

Figure 2 below illustrates an example coming from their analysis. In the beginning (Fig. 2b), the grounding line (separation between the grounded ice sheet in blue and the floating ice shelf in purple) is located on top of a small mountain range. When running the model under a global warming scenario, the grounding line retreats inland and the glacier enters into a ‘collapsing phase’ (Fig. 2c; marine ice sheet instability). The introduction of an artificial island under the ice shelf with a potential to block half the warm ocean water allows the ice shelf to reground (Fig. 2d; the ice-shelf base touches the top of the small island below). The unprotected seaward part of the ice shelf shrinks over time, while the protected inland part thickens and regrounds (Fig. 2e-f), which overall decreases the glacier mass loss to the ocean.

Figure 2: Example of a model experiment realized on Thwaites Glacier by Wolovick and Moore (2018). Different times are presented and show the (b) initial state, (c) the collapse underway, (d) the initial effect of the construction of the artificial island below the ice shelf, (e) the removal of the seaward ice shelf and thickening of the landward ice shelf, (f) the stabilization of the glacier [Credit: Figure 5 of Wolovick and Moore (2018)].

In practice

The model experiments presented above show that delaying sea-level rise from glacier outflow is possible in theory. In practice, this would mean substantial geoengineering efforts. For building a small artificial island under the ice shelf of Pine Island Glacier (West Antarctica), 0.1 km3 of gravel and sand would be necessary. That same quantity would be sufficient to build a 100 m high wall in front of Jakobshavn Glacier (Greenland) to prevent warm water from melting the ice base. For building such a wall in front of Pine Island Glacier, a quantity of 6 km3 (60 times more than Jakobshavn) of material would be needed.

In comparison, the Three Gorges Dam used 0.03 km3 of cast concrete, the Hong Kong’s airport required around 0.3 km3 of landfill, and the excavation of the Suez Canal necessitated 1 km3 of material. Thus, the quantities needed for building glacial geoengineering structures are comparable in size to the current large engineering projects.

However, many other aspects need to be considered when implementing such a project. In particular, the construction of such structures in cold waters surrounded by icebergs and sea ice is much more difficult than in a typical temperate climate. A detailed study of physical processes in the region of the glacier, such as ocean circulation, iceberg calving, glacier sliding and erosion, and melting rates, is needed before performing such projects. Also, the number of people needed to work on a project of this scale is an important factor to include.

Potential adverse effects

Beside all the factors that need to be considered to implement such a project, there is a list of potential adverse effects. One of the main risks is to the marine ecosystems, which could be affected by the constructions of the islands and walls. Also, if not properly designed, the geoengineering solutions could accelerate the sea-level rise instead of delaying it. For instance, in the case of water extraction (proposal A above), the glacier might speed up rather than slow down if water at the glacier’s base is trapped in pockets.

Wolovick and Moore (2018) do not advocate that glacial geoengineering is done any time soon, due to the different factors mentioned above. Instead, they suggest that we start thinking about technological solutions that could delay sea-level rise. Other studies also look at different glacial geoengineering ideas (see this post).

In summary

Glacial geoengineering techniques constitute a potential way to cope with one of the greatest challenges related to global warming, namely sea-level rise. In theory, these projects are possible, while in practice a series of technical difficulties and potential ecological risks do not allow us to implement them soon.

While important to keep thinking about these solutions, the most important action that humanity can take in order to delay sea-level rise is to mitigate greenhouse gas emissions. And scientists like us need to keep carefully studying the cryosphere and the Earth’s climate in general.

Further reading

Edited by Jenny Turton


David Docquier is a post-doctoral researcher at the Earth and Life Institute of Université catholique de Louvain (UCL) in Belgium. He works on the development of processed-based sea-ice metrics in order to improve the evaluation of global climate models (GCMs). His study is embedded within the EU Horizon 2020 PRIMAVERA project, which aims at developing a new generation of high-resolution GCMs to better represent the climate.

 

Image of the Week – What’s Hot in the Cryosphere? A 2018 review

Image of the Week – What’s Hot in the Cryosphere? A 2018 review

Every year, humanity understands more and more about a remote and unforgiving component of the Earth system – the cryosphere. 2018 has been no exception, and in this blog post we’ll take a look at some of the biggest scientific findings of cryospheric science in 2018. We will then look forward to 2019 and beyond, to see what the future holds for these rapidly changing climate components.


The Cryosphere at 1.5°C warming

In 2018, the IPCC (Intergovernmental Panel on Climate Change) released their report that looked at the impact of 1.5 and 2.0°C of global warming by 2100 on the Earth system. In the Arctic, warming is already in excess of 2.0˚C, driving a very strong decreasing trend in the summer sea-ice extent. The IPCC suggest that sea-ice-free summers will occur once per century at 1.5°C, but this increases to once per decade at 2.0°C. Limiting warming to 1.5˚C will also save 1.5-2.5 million km2 of permafrost thaw (preventing the release of ancient carbon into the atmosphere), 10 cm of sea-level rise contribution from ice sheets and glaciers, and reduce the risk of the irreversible collapse of the ice sheets. Read more about the cryosphere under 1.5°C warming in this previous post.

 

Mass Balance of the Antarctic Ice Sheet

Compiling 24 independent estimates of mass balance, from a number of different remote sensing and modelling techniques, the IMBIE team produced the best estimate of how Antarctica is responding to continued climate warming. The mass balance refers to the net change in ice mass, accounting for all of the inputs and outputs to the ice. They quantify that ice mass loss from West Antarctica has increased three-fold between 1992 and 2017, largely due to melting from a warmer ocean. On the Antarctic Peninsula, the collapse of ice sheets has led to an increase ice mass loss by a factor of 4. East Antarctica is gaining mass slightly, although this is highly uncertain, by 5 ± 46 billion tonnes per year. Overall, Antarctica has lost 2,720 ± 1,390 billion tonnes of ice in this 25-year time period, and this mass loss is accelerating. Read more about these results in this previous post.

Mass loss from the Antarctic ice sheet is accelerating, largely due to ocean warming impacting West Antarctica. East Antarctica is very slightly gaining mass, but this doesn’t go anywhere near balancing out mass loss across the continent [Credit: NASA Goddard].

A polluted cryosphere

It’s easy to think of the cryosphere as a pristine, beautiful, untouched landscape. However, research from 2018 has shown us that the remoteness of Polar Regions has not protected them from man-made pollution. In one litre of melted Arctic sea-ice, 234 particles of plastic and over 12,000 particles of microplastics were found, which will only go onto adversely impact Arctic wildlife by spreading through the ecosystem. Radioactive material from the Chernobyl accident has also been found to be concentrated in dark sediments found on Swedish glaciers. As these glaciers melt, this concentration of radioactive material may be released in meltwater. In Greenland, lead pollution found in ice cores has provided exciting new insight into wars, plagues and invasions during the Roman Empire.

In 2018, we saw a glimpse of the geological secrets that Greenland hides beneath its ice sheet. However, there is still a hidden world that future field-based campaigns or airborne radar missions will help to unravel [Credit: NASA Goddard].

What secrets is Greenland hiding?

In 2018, we got our best ever look beneath the Greenland ice sheet. Scientists from the British Antarctic Survey and NASA found that the hotspot (a thermal plume in the Earth’s mantle) currently under Iceland was once beneath Greenland, between 80 to 50 million years ago. This hotspot was discovered by studying the magnetism of minerals beneath the ice. Using airplanes, radio waves and sediment that’s washed out from underneath the ice sheet has also revealed a massive 31 kilometre wide meteorite crater underneath Hiawatha glacier. Given it’s beneath three kilometres of ice, the age of this crater is unknown, but given the interest and speculation in connecting this event to an abrupt cooling period 12,000 years ago (the Younger Dryas), we may know very soon.

 

Blast Off!

Satellites remain one of the most popular methods of monitoring the vast, hostile cryosphere. In 2018, a new generation of earth observation missions launched. ESA’s Sentinel-3B continues the Copernicus programme, monitoring the reflectivity of the ice, elevation and sea-ice thickness. NASA’s GRACE FO mission continues the successful first GRACE mission, which used gravimetry to ‘weigh’ different regions of ice. NASA also launched ICESat-2, which will provide global elevation data at unprecedented spatial resolution on a 91-day repeat orbit. Each satellite is being finely tuned to make sure it’s working exactly as intended, and we’ll get the first science from them in 2019. Stay tuned!

Remote sensing data has provided us with answers to some of the biggest questions in the cryosphere. We use it to help quantify mass loss, sea-level rise and glacial retreat. In 2019, new missions will take our knowledge of cryospheric sciences to new heights! [Credit: Liam Taylor]

A look ahead to 2019

On the ground, getting inside the ice will continue to provide fascinating insights into the history of the cryosphere – from reconstructing winds in sub-Antarctic islands using ice cores, to further insights deep inside the world’s highest glacier. As permafrost continues to thaw, we are likely to hear of more discoveries of woolly mammoths, ancient diseases and carbon release. The IPCC will also publish their special report devoted to The Ocean and Cryosphere in a Changing Climate, which will provide the best overall state of the cryosphere to date. And, of course, the infamously named ‘Boaty McBoatface’ will provide us with incredible data from beneath sea-ice and ice shelves when the RRS Sir David Attenborough is launched. 2018 has been a truly exciting year to be a cryospheric scientist, and 2019 looks set to be another hot one!

 

Edited by Adam Bateson


Liam Taylor is a PhD student at the University of Leeds and Centre for Polar Observation and Monitoring. His research looks at identifying novel remote sensing methods to monitor mountain glaciers for water resource and hazard management. He is passionate about climate change and science communication to a global audience, as an educator on free online climate courses and through his personal blog. You can find Liam on Twitter.