Cloud-hunting at high altitudes

Article written by Hanne Notø, December 23, 2022

The night train brought me to Vienna in the early morning of Monday November 21. There, I was meeting my colleagues from TU Wien who were coming with me to my field campaign at Mt. Sonnblick. We set off towards the Alps, the car packed with sampling equipment, clothes for -20 C, and of course the essentials: snacks. We reached the end of the Rauris valley, but from there we could only reach the observatory at 3106 m using the gondola. The ride up was spent in complete darkness, but we could see the light of the observatory up on the top of the mountain.

The gondola taking us and the equipment up 1500 m to the observatory. The photo on the right is the observatory seen from the gondola in daylight

After arriving at the observatory we were served dinner and got to meet some of the other scientists who were there at the time. Coinciding with my stay at Sonnblick was an intercomparison campaign on cloud droplet measurements. The goal of my stay at Sonnblick was to collect cloudwater, snow and aerosol particle samples. The composition and concentrations of semi-colatile organic matter in the samples will be compared. The samples will be analyzed using a Thermal Desorption Proton-Transfer-Reaction Mass Spectrometer (TD-PTR-MS), which allows us to measure semi-volatile organic compounds in different matrices. This allows us to compare aerosol particles on filters with liquid samples such as cloudwater and melted snow. This will help better understand the transport of organic matter in the atmosphere and how it is deposited on snow, which may help the interpretation of organic matter in ice cores.

Since the location of the Sonnblick observatory is quite remote, this will allow the collection of relatively ‘clean’ samples, representing European background levels. Past studies on aerosols at Sonnblick also serve as grounds for comparison, which may help the analysis and interpretation of the data.

PM1 aerosol filter sampler. Air is pumped from the outside of the observatory and passes through a filter where particles are trapped.

Collecting snow samples from the surface

On the first morning, we set up the cloudwater sampler and aerosol filter sampler. We then made a sampling plan and decided on the division of night-shifts. The cloudwater sampling was quite time-intensive and required us to check or collect the sample every 30-60 minutes. If it was cloudy around the observatory during the night, somebody had to stay up and collect the samples.

The cloudwater sampler: air is pumped through a narrow slit and smaller particles are directed around the sampler inside (depicted on right), while larger cloud water droplets with too high momentum collide with the plate and freeze upon impact. This forms a “cloud ice cube” in the shape of the slit, which can be collected.

In the time between sampling and when it wasn’t cloudy, we tried to get some sleep and do some work. There is a hiking hut connected to the observatory, which is where we slept and ate. All our meals were prepared by the hut manager, who was kind enough to keep the hut open while us scientists were there. Normally the hut is only open in the summer months, when the mountain is accessible for hiking. In the winter it is difficult to hike in the area, and because of the snow, glaciers and cliffs surrounding the hut. We could therefore only walk on one side of it, plus the terrace on the top of the roof where the instruments were mounted. In other words, we spent a lot of time indoors. When the weather was clear, the view was incredible! I added a few photos below, but I took a couple hundred photos during my stay !!

The first few days I could feel the altitude’s effect on my body. I felt persistently tired, couldn’t sleep well for the first few nights and felt like my heart was in my throat every time I walked up the stairs. Nonetheless, samples were collected and logged, and we collected cloudwater from every cloud event that occurred. Occationally, the cloudwater sampler would freeze shut. When that happened we had to carefully remove the sample, scrape away the frost and insert a clean sampler. The longest cloud event we observed lasted 23 hours. We were sampling day and night, and collected a total of 26 cloudwater samples. During the entire campaign, a total of nearly 100 samples were collected. These samples will be analyzed in Utrecht in January 2023.

After ten days of staying in the hut, I felt quite ready to go back home to my normal routine. However, I really enjoyed my time at Sonnblick and would love to go back if given the opportunity! I would like to thank the staff at Sonnblick and the people at TU Wien who came with me just to help me collect samples, my campaign would not have been possible without them.

Auf wiedersehen!

A trip to Switzerland: looking for glacier basal ice

Article written by Lisa Ardoin, on the 16/06/2022

The focus of my thesis is the gas measurement concentration in a specific section of the ice core: the basal section. One of the specificities of this ice, is the presence of debris (ranging in size from few centimetres to clay) between the ice crystals. These debris make the measurements a bit touchy because most of the analytical techniques used in ice core sciences are specifically designed for ice, clear ice, without particles in it.

To develop an analytical method specific to the basal ice, I needed samples close to the ones from Antarctic ice cores but less precious to test what the best way is to release the gases trapped within the ice crystals and between the debris. This is how we came up with this idea to sample continental glacier basal ice in the Alps.

At that point, I was thinking that it would be an easy and short mission of 2-3 days… I was wrong! When we started to discuss the mission with my supervisors, F. Fripiat and J.L. Tison, they told me that we would need a whole week to prospect different glaciers and then to sample the most interesting ones. We decided to go to Switzerland, in the canton of Valais, where there are rock glaciers.

Map of the glaciers of interest

Then, came the logistic part: the choice of the vehicle, gathering the equipment in duplicate, finding a good accommodation from where we would be able to reach the different glacier valleys, bringing a fridge (and two generators) with us to preserve the samples on the way back to Brussels!

Our racing truck for the week, full of equipment 

We left on May 21^st, with a 11m³ truck full of material. During the first four days, we went on and on at the different spots: Tsijore Nouve, Moiry, Tsanfleuron, Grubben glaciers. We faced many difficulties in the field. The main one was finding the basal ice layer that is not always present or accessible. And we realised once on site, after 1 to 2 hours of driving in the mountains and a hike of at least 2 hours, that the snow abundance above 2800m high was still hiding the front of two glaciers we were aiming (Tsanfleuron and Gruben glaciers). Also, the road to reach Moiry glacier was closed because of avalanche risk, and it was not possible to bring the truck with the equipment close to the glacier. So, the Tsijore Nouve glacier, the first one we visited, was the only one sampleable.

Front of the rock glacier Gruben 

On the two last days of our mission, our fridge and the icepacks were cooled down to -25°C: we were ready for sampling. We came back to Tsijore Nouve glacier and carry the equipment (chainsaw, cool bags full of icepacks to name only the heaviest material) until the spot we noticed few days earlier. We carried the material for 500m up, on 1km-distance, without a path, in the moraines. That was the easy part compared to the way back to the truck when we had a 30kg block of ice to carry in the cool bags off our backs!

The sample site (white arrow) at Tsijore Nouve glacier 

We were able to bring 5 blocks of ice for a total amount of about 140kg of ice containing 2 basal ice sequences. A successful mission, rich in emotions and in physical exercises 😊  

One of the basal ice blocks just after its extraction 

A part of the sampling team, after we cut the last block of ice from back to front: F. Fripiat, L. Ardoin, J.L. Tison

An insight of the 1st DEEPICE training school

Article written by Romilly Harris-Stuart and Piers Larkman, on the 25/05/2022

In early March, we – 25 PhD students – travelled to a sunny Copenhagen to join the ICAT training school (Ice Core Analysis Techniques) held at the Niels Bohr Institute. This trip was followed by the first DEEPICE training school in Finse. Here, I (Romilly) will write about our time in Copenhagen, then handover to Piers, another DEEPICE student, to describe our travel between Copenhagen and Finse. In the final part of this blog Piers and I will present a side-by-side day-by-day report on our time in Finse.  

Rom and Piers, the authors of this blog post!

Monday to Wednesday 14th – 16th March

To start with, our 5-day course in Copenhagen included a mixture of lectures from local professors, journal article discussions in small groups, and tours of the laboratories. During the first half of the week we were all brought up to speed on the history of ice core science and the development of techniques since the 1960s, when the first Greenland ice cores were drilled and studied at the Niels Bohr Institute.

Thursday – March 17th

With the intention of reducing our travel carbon footprint, the DEEPICE annual meeting was tactically scheduled to coincide with the ICAT training school. All 15 DEEPICE ESRs were present – minus Daniel who, while in Copenhagen, was trapped in his hotel room by covid – while those supervisors and board members who were unable to join in person were included seamlessly by Marie’s (DEEPICE Project manager) hybridisation skills.

Morning lectures were followed by individual meetings with the training board, giving those of us who required it some time to catch up on emails and to prepare for our presentations on the following day. To finish the day, we were all treated to a delicious meal, which presented a great opportunity to ask any questions that surfaced from the week’s lectures.

 Friday – March 18th

 Friday saw the last DEEPICE meetings with a brief intermission for a statistics lecture being held for the ICAT students not within the DEEPICE network. To finish up a great week, we re-grouped with all the ICAT participants for a farewell meal, happy in the knowledge that we will all meet again at the IPICS conference later in the year.

DEEPICE group in Copenhagen

Rom’s perspective

Monday – March 21st

Our group started the week with indoor training on an instrument which produces data that is vital for reconstructing temperature records from ice cores. The different isotopes of oxygen and hydrogen in water molecules store information about the climate during the time the snow was deposited and exposed at the ice sheet surface.

As is often the case for field courses, the first part of the day was a lesson in patience and perseverance. An issue with a key component of the Picarro instrument – used to measure isotopic composition of water – resulted in an impromptu lesson in fixing instrumentation in the field, with scarce access to tools. Fortunately, with the expertise of Magdalena and Mathieu and the brute force of Jens – our station manager – the issue was solved by the unconventional removal of delicate screws with an ill-fitting screwdriver.

After this minor set-back, we were able to start measuring the water samples which each student had brought from their home institution. We had with us some snow samples from Little Dome C, the site for the Beyond EPICA Oldest Ice Core.

Tuesday – March 22st

Eager to get outside, our group of six had field logistics and safety planning which started with blizzard simulation aptly described by Piers. Unlike Piers’ group however, we managed to rescue Bo with our fan-like strategy. The success was slightly tainted by Niklas, who was at the far end of the rope, walking up the roof of the old research station. Our main learning outcome was to always consider your surroundings.

After lunch we discussed the ups and downs of running an ice coring project, simulating the luck of the draw with breaking/fixing of machinery, personal illness, the weather and plenty more variables, to see how our project may have gone.

Coin flip

With bad weather predicted for the coming days, we made the most of our newly discovered shovelling skills and built an ice bar where we spent the evening listening to field stories from the lecturers. (It turned out the weather forecast was wrong, as expected, and the sun came back the following day).

Wednesday – March 23rd

With the arrival of Hubertus Fischer came the first day of training in snowpack properties. We started inside with some theory and planning of what we want to measure and the equipment that would be needed. Finding an optimal place to dig our snow pit involved probing the snow to determine the depth of the snowpack. Uneven topography, and high winds near the research station causes strong heterogeneity in the snowpack, with some areas of exposed rock/surface and others with 2m snow depth. Having found a goldilocks site with 1.3m snow depth, the pit was dug and measurements were carried out. Two ice layers 10cm apart were identified at a depth of ~1m corresponding to rain events in December 2021.

By the end of the day we had drawn up our snow profile with information about snow properties such as density, hardness, grain size and grain type. The benefit of having three groups making snow profiles at different sites around the station was that we could compare the spatial variability in the deposited snow. Uneven accumulation is common even in remote regions of the ice sheet, highlighting the importance of replicate measurements.

Thursday – March 24th

With the retreat of the sun, we moved inside for day 4 to develop our understanding of the usefulness of climate models and bring our awareness of their limitations in regions, such as Antarctica, where sparse data limits the accuracy of reanalysis data.

Our round-table setup facilitated the sharing of expertise which was beneficial given the range in abilities in both climate modelling and coding in Python.

The living area in the old research station, where we were located for the day, had the perfect setup for the day, with some music on an old record player and unlimited tea and biscuits.

Everyone at Finse

Friday – March 25th

As promised, the wind picked up for our last day which meant we were able to put into practice our field and logistics training to install the weather station at an optimal site, or in other words, we needed to find a spot where there would be no hiding from the wind. Having cheated by doing a test-run inside, the station was set up at (arguably) record speed leaving us the afternoon to download and analyse the weather data from the week.

Pier’s perspective

Monday – March 21st

To start the day, a plan to remove our infected colleague from the center to somewhere comfortable was devised with help from the local health authority. In the meantime we decided to dig, an emerging theme for the week, away the snow drift covering our colleague’s room to give them some light during their confinement.

Once we moved to the task at hand my group were discussing the logistics, and challenges, of ice coring operations in sub-zero and snowy conditions with Bo Vinther and Kerim Nisancioglu. One challenge Kerim faced us with was that Bo had managed to get ‘lost’ in a ‘snowstorm’. Clearly actually getting lost isn’t something someone as experienced in the field as Bo is likely to do, and there wasn’t a snow storm in sight. So, we got creative. We were handed a bucket to put over our heads to simulate a whiteout, and a piece of rope, and told that we had to find Bo somewhere within a 15m radius of the research station.

It’s a harder task than it sounds, and maybe a good exercise for anyone reading this blog to think how they would organise and execute this search and rescue mission, we didn’t manage, I hope Romilly’s team did…

Ailsa, Piers and Geunwoo shifting snow

Bo watching our helpless attempts at saving him

Tuesday – March 22st

Day two at the research station for group 2 involved learning how to set up a weather station. Led by Hans Christian we discussed the components of a simple weather station. In our case we had a station consisting of a thermometer, anemometer and a hygrometer, alongside a supporting structure.

We selected an appropriate spot and, despite the cold and a few mistakes, put the station together and started it off logging data using a script coded for our specific instruments. For those of us who enjoy coding, this was a good sign of things to come!

An almost fully set up weather station!

Wednesday – March 23rd

Day three involved a lot of code, it was modelling day. Climate models simulate drivers of climate, in our case focusing on the atmosphere. Courtesy of one of our fellow PhD students, Quinggang, we had been set up with a great starting point to model various climate systems that have influence over the Antarctic continent.

Evenings in Finse involved various adventures nearby the station. As Rom mentioned an ice bar was dug, also snow-people were made and the surrounding area was explored, with some on foot and others skiing.

Ines skiing

The snowy landscape around Finse

Thursday – March 24th

Thursday was water isotopes day. Thanks to Rom’s teams heroics on day 1 we had a working Piccaro. Stable isotopes have been at the center of ice coring since its inception. The core idea is that the specific isotopic composition of atmospheric water varies based on the temperatures it has experienced during its evaporation and precipitation (and at other stages). This means if you can measure the isotopic composition of water, which you can with e.g. a Piccaro, you can understand the (average) temperature of the location of the water’s source, which we did.

Revisiting the theme of digging, there was an immense amount of snow-shifting and snow-based-creation that went on. Fuelled by the excellent food on offer at the station, here are some pictures illustrating the range of snow pits, snow tunnels, snow drifts, igloos, and snow-people that were dug/made.

Ines and Claudio preparing an ice pit.

Piers not contributing to the construction of an igloo.

Friday – March 25th

Our final day of training activities was concerned with snow pack observations.

Following from Rom’s group on Wednesday, Friday saw my group look at the snowpack. The basic principle of ice coring is that snow builds up in layers, with sequential layers burying those that fell at earlier times. This gives a record looking back in time, providing the ice isn’t badly disrupted below the surface. Using this principle, and skipping the hard work by using the pit that had been dug in the days prior, we recorded information about the properties of the snow and took snow samples from a cross section of the snowpack.

Florian admiring the layers through the snow pit wall.

Stories from the field

Article written by Inès Ollivier, on the 23/02/2022

A few weeks ago, I came back from a field campaign in Antarctica, at the research stations Dumont d’Urville and Concordia. I left Europe on November 18^th and two months and a half later I landed back in Paris. A lot of this time was spent in quarantine and travelling, and the rest working in the field and living the life on these two different stations.

I first arrived in Dumont d’Urville (nicknamed DDU), a French coastal research station located on a small island 5 km away from the continent, where I stayed for a month. I was working for a research program called ADELISE, aiming at studying the evolution of the water cycle and the modification of the water stable isotopes from evaporation to precipitation in the coastal region of Adélie land in Antarctica. One of the goals of this program is to better understand the origin of the snow surface accumulation in this region of the world and also to understand the recent climatic evolution through the study of water isotopes. In order to do so, several experiments and instruments have been set up and are operating all-year round, including snow surface sampling and a water vapor analyzer (PICARRO) measuring continuously the isotopic composition of the atmosphere. The analyzer was installed some years ago and needed relocation and maintenance this year. When I left, one of the winterover crew members took over and is now in charge of the instrument during the wintertime, when nobody can access the station for 8 months. I also got the chance to contribute to other research programs in the field, such as the preparation of a trench on the closest glacier l’Astrolabe, which was going to host a seismological station to measure and record the movements of the glacier; or measurements of snow accumulation across a field of stakes located on the continent close to shore.

Snow surface sampling in DDU and the caravan where the experiments are installed

New set up for the water vapor analyzer inside the caravan and snow accumulation measurement on the continent

Other than work, I got to spend my time taking part in the life of the station and enjoying the surroundings. We were about 60 people on the station, sharing social moments and places. For Christmas, we shared handmade gifts, a delicious meal, and had a nice evening. Especially while being away from home, it was nice to share a special moment and feel a bit of the Christmas spirit. I went on a great walk on sea ice during one of my days off to discover the surroundings of the station. We walked by a penguin colony, saw some juvenile emperor penguins, Adélie penguins (which are smaller than emperors), some seals and lots of birds. It was a beautiful day and it really felt like I was in a documentary! After New Year’s Eve, the chief of the station organized a bathing in the Southern Ocean. The water was close to its freezing point, recorded at -1.3°C, but it was one of the things I was so excited to do going there! So, we went to the ‘beach’, a nice area on the island where you can easily go in the water, and most importantly, go out quickly. We had very warm conditions for a few days, around +7°C during the day, and that really felt like summer. I was working outside in t-shirt, not being even cold. Few days later, a storm came, and that was a lot different … It became hard to even walk from one building to another! Overall, I really enjoyed the time I spent there, surrounded by a beautiful landscape just outside the window.

Christmas greetings from Dumont d’Urville 

The station at sunset and the Astrolabe glacier behind

Juvenile emperor penguins on sea ice in front of icebergs

Weddell seal and an Adélie penguin brooding its egg

After the work was done in DDU, I took a small plane for four hours, to get to the inland and French-Italian station Concordia, where I stayed for 10 days. The station is located 1200 km from the coast, at 3200 meters elevation. There, I was in charge of the reinstallation of another water vapor analyzer, the same model as the one in DDU. These measurements are used to understand the isotopic transfer function between the coastal region and the East Antarctic plateau, as well as interpret the isotopic profiles measured in the deep ice cores drilled in this region of Antarctica. The goal of my stay there was again to make sure everything was working well for the upcoming year, and characterizing the instrument by doing several calibrations. Besides that, I performed some intensive snow surface sampling, for three days and three nights, to capture the evolution of the snow surface isotopic composition on the diurnal scale. Part of my PhD project will be to use all these field data to understand how stable water isotopes are evolving in the atmosphere, the precipitation and the snow surface and how the atmosphere-snow exchanges are impacting the isotopic climate signal stored in the snow surface later transformed in an ice core.

Basler plane to go to Concordia

Instrument set up inside a buried shelter 1 km away from the station and the inlet of the sampling line outside

Snow sampling at Concordia

Because it is so high in altitude, and also because I got the covid vaccine in DDU right before leaving for Concordia, I spent the two first days after arrival resting and acclimatizing inside the station. Then I was very busy with my experiments, so I didn’t do much besides work. Nevertheless, I enjoyed spending time with people during meals and gatherings at night; and walking around the station to admire the purely flat and white horizon that is so special about this area of Antarctica. The weather was mostly good, cold of course, with temperatures reaching about -35°C and -45°C windchill (how the temperature actually feels because of the wind). Fortunately, we were very well dressed to cope with these conditions, with about 8 kg of clothing and heavy boots!

Concordia station

View of the station and its surroundings from the top of a 43 m high tower

Once the experiments were finished, I took a plane to return to DDU, where I spent one last evening on the station before boarding the ship. The next morning, we waved goodbye to the people staying from onboard, and we started our journey back to Tasmania. The way back took approximately five days and then we spotted the mountains of Tasmania. Some dolphins in Hobart’s Bay to complete the trip, and we were back to civilization. It took some extra days before we could go out of the ship and enjoy an afternoon in town before taking the plane back to Paris. After the last goodbyes in the airport, it was time to go home … this field mission was very enriching and a wonderful experience!

View of the station and its surroundings from the top of a 43 m high tower

A journey to the other side of the world

Article written by Inès Ollivier, on the 29/12/2021

My journey to Antarctica began on November 11th, 2021, when I boarded a plane to Paris to spend a week with family and friends before the departure. A week later, I was back in Paris to catch the plane that would bring me to Hobart, Tasmania, Australia. It took 3 planes, two stopovers in Singapore and Melbourne, 17 000 km and approximately 30 hours of travelling to finally reach destination. Well, not quite yet… but a first step towards the white continent.

The purpose of this travel was to go on field mission for my PhD project. I stayed at the two research stations Dumont d’Urville and Concordia to install and maintain instruments measuring the water isotopes in the polar atmosphere and collect snow samples to study the exchanges of water isotopes between the atmosphere and the snowpack at the diurnal cycle. These data will be used to better understand the water cycle dynamics in Antarctica and the climate signal imprinted in the snow.

I travelled with a group of about 40 people, scientists, technicians, some will be staying a year and others, like me, just a couple of months. In the empty airport, the authorities welcomed us already knowing that we would be only passing by before leaving for Antarctica. Hobart is one of the entry gates towards Antarctica, and France have historically been going through this town during polar expeditions, as of Jules Dumont d’Urville with his crew when they discovered the Terre Adélie.

After landing, a bus led us to a hotel in the city center, not so far from the harbor, where we spent the following two weeks in strict quarantine. Because of the covid pandemic, the French authorities put in place a period of isolation for each Antarctic expeditioner, to prevent the virus entering the continent and risking the lives of the people already on the station. There, the possibilities to evacuate a sick person are very limited, as well as the hospital capacities to treat severe illness or injury.

It was nighttime when we arrived in Hobart, so we couldn’t see much of the area, but at least the refreshing smell of wet eucalyptus in the air. Once at the hotel, the staff escorted me to my room, home for the next weeks. Starting from this moment, I was not allowed to go outside, to see other people, to get too close to the guards. Nevertheless, the room was very nice and comfortable, kind of a small apartment. A lounge area, with a couch and a coffee table, a corridor and a big double bed and bathroom. It was on the ground floor, and there was a window and a door close by the bed with a view on the outside. I could see some trees, and from time to time a guard passing by. Of course, I couldn’t open the door to enjoy outside, but I was allowed to open the window a bit to get some fresh air inside. The food was brought three times a day and deposited outside my room on a chair by the door. I had to wait a couple of minutes before opening the front door and grab the food that I could eat inside my room.

My hotel room, the view on the outside

During the following days after our arrival, we took a covid test and when the result came negative, we were allowed to go outside once a day, for 30 minutes, in a small, dedicated area. I enjoyed this moment, where I could walk a bit, and sometimes even do a bit of running! Otherwise, I kept myself occupied with work, reading, exercise or knitting. The first week went relatively slow, the challenging part was to not be able to go outside when I wanted, but during time slots fixed the day before. The second week flew by, and in no time, I was out!

A bus came to pick us up at the hotel and took us to the harbor, where we discovered the icebreaker that would take us to Antarctica: l’Astrolabe. It was not the first time I was seeing it, but still the same strong feeling of excitement to board it and ship towards the white continent. The marines warned us on the dock that it was going to be a rough crossing, the ship will be moving a lot, especially since it has a flat bottom to move through sea ice. We spent the first night in Hobart’s Bay, safe from the waves, and the next day we started moving towards south. A couple hours later, the waves were already 4–5m high, and I was not
able to stay longer at the bridge of the ship, so I went back to my cabin. I almost got sick, but layed down and didn’t go out for the following 26h. The doctor came and gave me some fruits to eat, the only food I had during that time. After this, I was feeling better, and hungry, so I went to dinner and could enjoy the rest of the crossing.

L’Astrolabe through the Southern Ocean and the Antarctic pack ice

A day before the arrival, we started to see some pack ice, sea ice broken into pieces. The ship went through it and continued its route. We passed by some big icebergs, saw some whales along the way, it was just incredibly beautiful. We arrived close to the continent at sunset, and spotted Dumont d’Urville just before going to bed. A last night on the ship, before setting foot on the ground!

The ship at Dumont d’Urville, Dumont d’Urville research station and an iceberg