Resupply at Casey went on smoothly despite one more time of stooging off the coast because winds were too strong to allow for any operations. We sailed out to the open water where we sailed back and forth at a very slow speed in a north-westerly direction. Luckily enough we got to cruise between icebergs presenting themselves in the most beautiful shades of blue.
The stooging also coincided with the summer solar solstice (the closest point of the sun to the Earth).
Luckily enough, the sun was out and we enjoyed the warm and breathtaking colors around 4 am during the night with pinky icebergs and a clear moon.
On the 23 December 2018 the winds calmed down and resupply could continue. Good progress was made and refueling started on Christmas Eve. During this 36 hour operation frequent crew change overs occur and in case of sudden changes in the weather, the bunker door needs to be attended at all times. We volunteered to be part of the bunker door team – not only during the refueling but the whole period during resupply. Being at the bunker door means lowering down bags to the zodiacs and getting luggage from the zodiacs into the ship, welcoming the arriving passengers and keeping track of who is on board.
As resupply went on until the 28 December 2018, official Christmas was moved to the day after we left Casey. Therefore, we celebrated the actual Christmas Day in a very unusual way; Salsa on the helideck and relaxing in the sauna. Besides attending the bunker door for about 4 hours a day, all of us got a chance to spend one day at Casey. With big thanks to Juan, we enjoyed a great walk around the station’s cross-country ski tracks. It was fascinating to see this icy and mystic scenery – and listening to the pure silence of Antarctica!
Resupply officially finished on the 28 December in the evening and shortly after we set sail accompanied by the ships horn and fireworks from Casey station. Winds picked up at the same time and we sailed northward – being unaware of what is waiting for us… We entered the sea-ice in the evening and it rapidly slowed down our progress. Easterly wind strongly compacted the ice forming so called pressure ice and even bashing the ice by going back and forth, the Aurora Australis couldn’t beat the power of nature. The engines were turned off and we were silently drifting with the ice in a south-westerly direction.
An attempt to sail on the next day was stopped after few hours. On the 31 December 2018, we finally sailed toward the south for another attempt to fight the pressure of the ice. The ice kept us trapped in Antarctica for New Years Eve, which we celebrated with a band concert, a fire and hot chocolate on the trawl deck.
The scenery was gorgeous and we enjoyed the sea-ice, the icebergs and their wildlife. Starting the new year in bright sunshine was very special and we celebrated the start of the new year with an Emperor penguin in front of the ship.
During a new attempt to get through the ice, we finally moved northward constantly and surprisingly easily and it was soon pretty clear that we would leave the ice soon. Taking a glance outside we could already see the open ocean and shortly after we left the sea-ice – a very emotional moment for many of us!
Then we steamed north-east, straight toward Hobart, where we arrived on the 7 January 2019. We experienced the furiousness of the fifties, as a deep low pressure system and its associated warm front passed over our track on 4 January 2019. With 30 knots of south-easterly wind and six meters swells, the Aurora Australis was rock'n'rollin’ towards the 50th parallel.
The sea got calmer when we approached Hobart. The smell of land and the green of plants overwhelmed us at our arrival and it was time to say goodbye to many new friends and for a week of holidays to explore Tasmania.
Being on our way home we say goodbye and let Alfonso take over the news of Antarctica!
Our time at Davis has come to an end. Alfonso arrived at Casey station onboard the Aurora Australis on 14 December, while I (Josué) flew from Davis to Casey on a rare trans-Antarctic flight, yet very important for the logistic of scientific projects on the southernmost continent. The flight was a great opportunity to admire the Vestfold Hills and the ice-sheet, aka the Plateau. Meanwhile, Fränzi was still at Davis station, waiting for the second flight to Casey. The map below features « Terra Australis », as the continent was called until the nineteenth century. Casey, one of three Australian stations on the Antarctic continent, is located approximately 1400 km east of Davis, on the same latitude as Perth, Western Australia.
Alfonso and I had the chance to meet and spend three days together on the Aurora Australis, while he waited for his flight to Davis. It was a good opportunity to transfer knowledge, analyse data together and take a picture to mark the occasion, as Alfonso sets-off to cover part 2 of this Antarctic research expedition.
View of Casey station from the Aurora Australis
He flew out to Davis on the morning of December 20 and Fränzi arrived in Casey on the aircraft’s return flight after it shortly refueled in « Whoop Whoop » as the skiway at Davis is called. We (Fränzi and I) are now waiting on the floating hotel « Aurora Australis » during Casey’s resupply. While most of the cargo has been off-loaded, refuelling the station has yet to take place. As most operations in Antarctica, the weather will dictate when the refuelling takes place. It is indeed a complex task that requires watercraft operators to work around the clock in 8-hour shifts over two to three days, as the pipe needs constant oversight to avoid spilling any fuel into the ocean. When the resupply is over, we will set sail to Hobart, Tasmania, while Alfonso operates our instruments for the remainder of the campaign. Stay tuned for new posts from his side, the campaign is not over !
Josué
While Josué left Davis on the 14 December 2018 (one day later than planned) my flight was planned for the 16 December 2018. As the weather turned bad at Davis as well as Casey the flight has been moved several times and day by day we learnt that our flight wouldn’t leave the next day. It even got moved to friday or saturday (21./22. 12.) on tuesday already due to the weather and accommodation situation. This gave room to plan some work for the days between – however, all of the sudden on wednesday morning the flight was moved to thursday (20.12.), when it finally happened.
Nevertheless, I experienced 5 more days at Davis station, looking after our instruments and getting them ready for a long winter. The extra-time at Davis was crowned by a sunday hike outside station limits to the Old Wallow and the Lookout. Despite some snowfall and slightly windy conditions, this was a great opportunity. Especially the view from the Lookout, from where we could see the Plateau, the Sorsdal glacier and many more of the Vestfold hills, was breathtaking.
With one crying and one laughing eye, I finally hopped in to the helicopter last Thursday around lunch time. It was sad to say goodbye to all the new friends who stay for the rest of summer – or even the whole year but it was amazing to get to see the Vestfold hills from the air. A stunning helicopter flight brought us up to “Whoop Whoop”, where we were transferred to the airplane.
As we were flying above 10’000 ft we got extra oxygen for most of our flight. While most of the flight was above the clouds, the landing at Casey was – once again mind-blowing:
After one night at Casey station, 4 hours time difference and very little sleep, I finally arrived on the good old Aurora Australis on Friday morning.
The installation of our instruments was a logistic challenge, since it required a helicopter to transport them to the site. First the helicopter flew four concrete blocks to anchor the radar, then the instrument itself took to the air. The flying spider got its first flight in Antarctica.
The flight was smooth and the structure remained quiet stable in the air, despite its odd shape and weight distribution. The pilot was able to stabilise the instrument just above the ground, while the engineers orientated it for a correct positioning. It must have been a real challenge, since it was quite windy.
After this demonstration of aerial skills, it was our turn to start working. For the radar the first tasks were to level the structure with the four feet, mount the flexible wave guides and the antenna and attach the feet to the concrete blocks. That was all we could do prior to getting power.
For the snow drift station, the tradesmen drilled holes in the rock to anchor three poles on which the instruments were mounted. When everything was installed, it was a good time to perform an initial terrestrial laser scan to have a reference before the first snowfall.
Two days after installing the instruments we had our first light snowfall. The image below shows a plan position indicator (PPI) radar measurement. This is a type of scanning where the radar antenna performs a 360° turn in azimuth at a constant elevation angle, in this case at 4° from horizontal. This gives a conic measurement through the atmosphere: the further from the radar the higher the radar beam will be. Without considering any scattering effect, the measurement you see at a radius of 10km from the radar will be at about 700m above ground in the case of a 4° elevation PPI.
More interestingly, what you can see on the PPI is snowfall over the Vestfold Hills and the Sorsdal glacier. Reflectivity is related to the precipitation intensity and hence the green areas are where the snowfall is the most intense. The “hole” that you see in the middle of the precipitation system region is because of beam blockage by a small hill to the south-east of the radar. Indeed this hill creates a blind zone for the radar, because it cannot see directly behind it. This is why operational radars are installed at a relatively high altitude, to avoid direct blockage. However here, it was not possible to install it on a hill for logistical reasons, therefore we have to deal with this beam blockage.
Once the ship left, the station got quieter. On Sunday (18 Nov 18) we got the opportunity to take part in a walk to Gardener Island. We were equipped with a field pack for the day. A backpack that contains all the gear needed in case we have to camp away from the station in the event of an emergency. The walk to the island over the sea ice took about an hour. We saw the first penguins on the sea ice.
They are heading out to the sea to feed, while their partner is breeding on the island.
From quite far away we could already hear them and later on, we could also smell them. The island is full of Adelié penguins.
It was amazing to see them in their natural environment, stealing stones, watching us with curiosity, laying on their eggs and running around.
Some are cleaner than others ;) …
… but they are all very cute!
While some walked to Gardner Island, I (Josué) had the opportunity to ski on the sea-ice to see the penguins with Mark and Terry. It was really awesome to ski in Antarctica in such a scenic environment!
Photo by Marc Raymond
We could see the ice-sheet of the Antarctic Plateau behind the Vestfold Hills. It looks like a stratus cloud, but it is a 2160m average thickness layer of ice that has been accumulated over millions of years. Its maximum thickness reaches 4776m in Terre Adélie, East Antarctica.
After another rocky night - not because of waves but as the ship had to bash through the ice – it was silent and calm in the morning when we woke up. We arrived at the «parking slot» about 1.5 km in front of Davis station at around 4 am in the morning. The sea ice has a thickness of about 1.7 m. Another few hours were required for logistics, lowering the gangway and preparing the road for the tracked over snow vehicle called a Hägglunds.
At around midday, we were driven to the station and we set foot on the Antarctic continent! We got lunch, an introduction to the station and time to settle into our rooms. It is impressive to be in such a remote place, but having this amazing infrastructure. However, it is even harder to imagine how the first pioneers, who set foot on the Antarctic continent, must have felt.
Being on land we couldn’t wait to see the surroundings. We headed out to inspect the proposed sites for our instruments and checked out the area within the station limits, where we are allowed to go without any further survival training. Some penguins came to visit the station, however, most of them live on Gardener Island an island about 3.5 km offshore.
During the first 8 days on shore the station was very busy with resupply – unloading cargo from the ship, storing food for the next year, refueling the station and stocking up the water resources and finally washing containers and reloading the ship. We joined the food storage team for a few hours to shuffle chicken, beef, french fries, ice cream, potatoes, apples, onions, cabbage, etc., etc., etc. from containers to their allocated storage. However, we mainly planned our work, went for site inspections to find good spots for our precipitation radar and the snow drift station and set up many of the instruments, which are part of our project. Unfortunately, we still have to wait for an approval to start with the installation of the main instruments.
Davis station is located in the Vestfold Hills, a rocky and hilly coastal region south of Prydz Bay. It is one of the few regions of Antarctica mostly free of ice and snow and thus represents an “Antarctic Oasis”. Davis station is also known as the “Riviera of the South” because it is rather warm in summer, with minimum and maximum average daily temperatures of between -1 and +3°C respectively. It is also rather dry with an average monthly precipitation of 2mm during the summer months. Since we arrived, we have had 2.5mm of precipitation in 4 hours, so we already reached the monthly quota.
The last few days on station passed quickly – we had to say goodbye to many of the winterers of last season and to Simon – the leader of our project when the ship left on Thursday heading back to Hobart. Thank you Simon for inviting us!
After 5 days of sailing through the sea-ice, passing icebergs and spotting Antarctic wildlife, we finally arrived in Antarctica. “Land ahoy!” yelled the first people standing on the front deck as we could see the Vestfold Hills standing out over the surrounding icebergs of the “Iceberg alley” formed by many grounded icebergs close to the shore.
At this stage, we were still sailing through some relatively thin ice and two hours later, we entered the fast-ice (i.e. the sea-ice attached to the continent). As this noun doesn’t suggest, it’s rather slow to get through, because the ice is thick and the icebreaker has to ram its way to progress by less than one ship’s length at a time.
During this process, we enjoyed the show of Adélie penguins walking and sliding on the ice, while Davis station could be seen in the background.
The first people from the ship to reach Davis, flew in by helicopter, they will start immediately with the station resupply. We will stay onboard during the night and will be driven the last two-three kilometers through the fast-ice when the Captain decides that the ice is thick enough for the vehicles to drive up to the ship for the over-ice resupply.
After 15 days, our voyage will come to an end and we are looking forward to leaving the ship and setting foot on the Antarctic continent!
It’s been 10 days since
we left Hobart. Time flies by and just recently we reached the sea ice. An
amazing scenery is accompanying us on our way to Antarctica.
In the first few
days, many of us were a bit seasick. The tablets made all of us sleepy and we
spent quite some time in our cabins. We headed straight south to avoid the 15 m
swells of a storm coming from the west. The scenery was the same all day long –
water as far as we could see… The highest waves we experienced were about 6-7
m, by far not as rocky as it could be when crossing the roaring forties and the
screaming fifties.
Before entering
the polar circle and its everlasting summer daylight, we had the chance to see
aurora australis two nights in a row! It’s the most spectacular natural
phenomena we’ve ever seen, a unique manifestation of the interaction between
solar particles and the earth magnetic field.
When reaching the
60° southern latitude we changed our route heading west around Antarctica. Two
days ago, a tiny peak at the horizon was spotted from the bridge – our first
iceberg, confirming that we are approaching the destination we are aiming for –
Antarctica! During the day we saw more icebergs even closer to our route.
Air as well as
water temperatures dropped over the last few days. One day after we spotted the
first iceberg, we reached the sea ice. A huge change in scenery, as stunning as
it can be!
Except from a
massive change in scenery, together with the ice the sights of wildlife have
drastically increased. We are now accompanied by birds and every now and then a
seal on an ice floe or a blow of a whale is spotted.
We even saw one
lonely emperor penguin and hope for many more to follow.
Stay tuned for our
imminent arrival at Davis research station, Antarctica!
The journey
to Hobart was long but smooth and the last few days were loaded with the last
preparations and information before departure. We got the equipment, which felt
to be way more than the expected : 7 kg!
People at
the Australian Antarctic Division (AAD) were so kind to allow us packing some
gear, which we do not need on the boat but once we will be on the station, in a
cardboard box and send it as cargo.
This is
only a small collection of the gear we were equipped with by the AAD:
Finally, we
had a one-day pre-departure training learning about hazards, having a physio
session getting to know how to lift and transport heavy gear, getting to know
how to dress ourselves in the cold, discussing expectations of the
expeditioners and meeting most of the expeditioners, which will be our working
colleagues and friends for the next few years.
We already
spotted the vessel - Aurora Australis – an icebreaker belonging to the AAD and
we are very excited to board it tomorrow to head south toward Antarctica!
Boarding the Aurora Australis
By Josué
Today is
the Big Departure: we’re boarding the Aurora Australis, the Australian
icebreaker. It will be a seventeen days journey in the Southern Ocean, covering
about 2600 nautic miles (4800 km) “as the crow files”. We’re obviously all very
excited about it. Before the ship’s departure, we had a whole briefing on safety
instructions, rules on the ship, sea sickness (yes it’s gonna be rock’n’roll!)
and a visit inside the lifeboats. We got to try the immersion suits, which are
meant for emergency situations in case we actually have to board the lifeboats.
It looks kinda funny, doesn’t it?
There are
also two helicopters on the ship, which can be used, for example, to unload
part of the cargo in case it’s not possible to do it on the ice at Davis.
The Aurora
Australis is a 95m long icebreaker and can transport up to 3900 tons of
material (deadweight tonnage). Its typical cruising speed is 13 knots (24
km/h), but when it actually has to sail through the sea ice, it decreases to
about 2.5 knots (4.6 km/h) depending on the depth of the ice. The Southern
Ocean sea-ice is now at about its maximum extension and we expect to enter it
at around 60°S. Davis being at about 68.5°S it gives you an idea of the long
journey we’ll have to cruise in the sea-ice. [Aurora_Australis.jpg]
Boarding
time is planned in one hour, so this post ends up here. Stay tuned for pictures
of stormy weather on the ocean and our arrival in Antarctica!
Preparation of the instruments is a critical step for
a successful measurement campaign. We recently acquired a new structure for the
radar: it consists of a four arm system with the radar in the middle and can be
mounted and dismounted from the trailer for transport. Before shipping this new
design we had to ensure that it is working properly. For that we ran a short
measurement campaign in the Jura mountains and took this opportunity to
calibrate the radar. Isn’t it looking awesome with the four arms deployed? It
looks like it’s ready to walk … walking maybe not, but at least it’s running
fine!
Just two days after this short calibration campaign,
we had to pack all the instruments to be shipped in a container. It’s the last
moment to think about anything we have to send to Davis for the campaign and to
make sure we don’t forget anything. It was a long day of work, but with the
help of our colleagues Etienne and Nikola, we were able tie up everything
properly inside the container. Have a good trip, dear radar, and see you in
Antarctica!
Testing – packing – sending
By Fränzi
… and hoping that
the instruments will arrive in Hobart in time.
While the
radar had to be shipped on the land- and seaway, the terrestrial laser scanner
and the instruments for the drift station could head toward Hobart on an
airplane.
To prepare
all the boxes, coming back from Siberia #SiberianSnowpack, I headed directly to
Davos to make sure all the equipment needed in Antarctica for the snow drift
station works and is packed for its journey. The good thing - in the middle of
boxes and cables there was no time for a jetlag!
The drift
station we send to Antarctica consist of a bunch of instruments to measure snow
drift and snow sublimation in a harsh and remote environment. A similar station
has previously been set up at another Antarctic station called Princess
Elizabeth, where it is running for two years already
The two
main instruments are the snow particle counter and the sonic anemometer. The
snow particle counter (SPC) measures the snow drift. It always turns into the
main wind direction due to the two wind wheels. On the other side of the
instrument a light signal is sent from a sending to a receiving unit counting
snow particles passing by and measuring their size.
The sonic
anemometer is an instrument to measure turbulence (small scale air motions in
the atmosphere). Therefore, wind speeds are measured in three directions at a
very high frequency. Once the mean wind is subtracted from these measurements
the remaining wind components characterize the turbulence. Atmospheric gases (e.g. water vapor and CO2)
are distributed in the atmosphere by turbulent fluxes. Therefore, high
frequency measurements of these gas molecules give information about their
atmospheric fluxes, which is important for example to calculate sublimation of
snow in the atmosphere.
In addition
to these main instruments, the station will be equipped with two conventional
wind sensors, a temperature and humidity sensor, a snow depth sensor and a
sensor measuring the surface temperature. The whole station will be monitored
with a camera showing whether the instruments are running fine.
After many
hours of testing and some changes of the electronics, finally the whole setup,
which is driven by autonomous software on a data-logger, ran smoothly. Once all
was packed in boxes we sent it on its way to Hobart – hoping for it to make it
to the boat in time!
While the
instruments are on their way – it’s time for me to think about my packing.
There are quite some constraints: Maximum baggage allowance including camera
and laptop of 30 kg, packed in (soft-sided) bags of max. 15 kg each. By the
Australian Antarctic Division (AAD) we will be equipped with cloths and shoes
needed for work, which will have a weight of about 7 kg. Additionally, cloths
with the logo of this years campaign will be added (having a unknown weight).
Thus, the gear I will bring should not weigh more than ~20 kg (including hand
luggage). On top of this, it is recommended to bring hiking boots for weekend
recreational hikes… Challenge accepted, I start to write a packing list
including weight of each item. And this is what’s going to join me to
Antarctica:
Meanwhile
the luggage made it to Hobart in time and for me its time to say good-bye to
Switzerland.
Alfonso Ferrone, Josué Gehring et Franziska Gerber will take turns at Australia’s Davis research station on the Antarctic
coast.
Hi everyone! We are a group of three who will travel south to study snow in Antarctica this austral summer. We are happy to introduce ourselves and our mission that draws us to travel to Antarctica.
My name is Josué Gehring and I am a second-year PhD student at EPFL in the Environmental Remote Sensing Laboratory. I completed my bachelors in environmental engineering at EPFL and my masters in atmospheric science at ETH Zurich. My PhD is about snowfall enhancement processes in mountainous regions and in Antarctica. I am particularly interested in two processes: aggregation and riming. Aggregation is when ice crystals collide and stick together to form larger snowflakes. Riming is the process by which ice crystals in clouds grow into large snowflakes by collecting super-cooled liquid water (liquid water below 0°C). These processes interact and lead to intense snowfall in the mountains. But how important are they in Antarctica? Are heavy snowfall events there also related to aggregation and riming? Studying snowfall in Antarctica is of major interest, because it is the main mass input to the ice sheet. With climate change, the ice sheet melts leading to sea level rise. Determining how much mass the ice sheet losses and gains is hence crucial to estimate future sea level rise.
To study snowfall in Antarctica, we will deploy a weather radar which measures precipitation and gives information on the size, shape and velocity of falling snowflakes. In addition, we will install a multi-angle snowflake camera, capable of taking pictures of falling snowflakes from different angles. All these instruments will be deployed at Australia’s Davis research station on the coast of East Antarctica. Davis is managed by the Australian Antarctic Division.
My name is Franziska Gerber, I am a Postdoc at EPFL in the Laboratory of Cryospheric Sciences (CRYOS). After finishing my bachelor studies in Earth Sciences and my master studies in Atmospheric and Climate Sciences at ETH Zürich, I knew my studies needed to be about snow or ice. Hence, it was a great chance to do my PhD with CRYOS and the Snow and Avalanche Research Institute (SLF) in Davos, where I currently live and work. During my PhD, I focused on the influence of mountain ridges on the local wind field and how the wind field affects the distribution of snowfall and its initial deposition in alpine terrain. - However, snowfall is not the only factor affecting the snow distribution. Wind and atmospheric conditions continuously alter the snow cover. Strong enough winds can lift up snow particles from the ground and blow them around. The humidity of the atmosphere determines if the atmosphere can hold the snow or if it sublimates (i.e. H2O molecules leave the solid snow phase to become part of the gas phase water vapor). - As mentioned by Josué, snowfall is important because it is the main mass input to the ice sheet. But does all the snow that has fallen remain on the ice sheet? Where is it transported and how much is lost back to the atmosphere? To estimate the potential ice sheet loss by snow melt contributing to sea level rise it is equally important to know how the snow evolves after deposition.
Thus, we augment the measurements with the weather radar and studies of snowflakes by a automatic snowdrift station. This station will be equipped with a snow particle counter (SPC), that measures the number and size of particles blown around, a sonic anemometer and gas analyzer which gives information about the sensible and latent heat fluxes (i.e. the energy released or consumed by temperature and phase changes) and standard measurements of wind, temperature, humidity, surface temperature and snow depth. As snow depth strongly varies depending on the location we additionally bring a terrestrial laser scanner with which we will determine the spatial distribution of the snow and changes of the snow surface due to snowfall and snow drift.
My name is Alfonso Ferrone, I am a first year PhD student at EPFL, in the Environmental Remote Sensing Laboratory, like Josué. I studied at the University of Trento for my bachelor, in physics, and at the University of Bologna for my master in Physics of the Earth System. Although this will be my first field campaign for the laboratory, it will be my second trip to Antarctica, since I spent one year in the research base Concordia as part of the Winter Over crew of the year 2017.
The focus of my PhD is on precipitation in Antarctica and in particular on the process of riming, which Josué already described, together with the reason why such a phenomenon is important in this particular environment.
In Davis, I will operate the radar for the second part of the campaign, as well as taking care of the multi-angle snowflake camera and pluviometer.
Franziska and Josué will travel south from Hobart, Tasmania, on the 25 October 2018 on Australia’s icebreaker Aurora Australis. It will take about two weeks to journey across the Southern Ocean to Davis research station. Once there, the Australian Antarctic Division will drop-off summer expeditioners and undertake a station resupply. Alfonso will head to Antarctica at the end of December when the time Franziska and Josué spend in Antarctica comes to an end.
The data we will collect will allow us to unravel the mystery of Antarctic snowfall, its accumulation, redistribution and its loss back to the atmosphere! So stay tuned for pictures of snowflakes, snow dunes, Antarctic landscapes and even penguins!