Mission belge Antarctique 2018
By Hugues Goosse
We are on our main field camp for one week and thus fully devoted to the data collection.
The weather conditions are generally good up to now, with perfect visibility and relatively high temperatures. This is ideal conditions for the radar measurements of the snow and ice thicknesses and of the structure of the snow layers.
Measuring snow thickness along several kilometers long transects using a radar in a sledge tracted by a snow mobile
By Hugues Goosse
I must admit that the title of this post was easy. When you sit on 500 meters of ice, there is a very small risk that you have no snow for Christmas, even in mid-summer. We could say 500 meters of ice only, because we are close to the coast. In the central plateau, it could be 4000 meters of ice.
View from our camp around midnight when the sun is the lowest (Photo Nader Wever)
As for many people, Christmas will be a special day here too. We do not have many options for clothes in our bags but we all made an effort to be as elegant as possible or to wear some special Christmas clothes and hats.
By Jean-Louis Tison
Well, it all depends on where, when and who you are!…
The first time I went in Antarctica, in 1987, it was with the British Antarctic Survey. We landed at Rothera Base, in the Antarctic Peninsula (the “tip” facing South America). There, the Base had recently been rebuilt, and the lifestyle was indeed already very comfortable: nothing to do with the first Antarctic explorers!
The Base was equipped with a full kitchen, cooking fresh bread every day .
The kitchen at Rothera Station in 1987 (Antarctic Peninsula, British Antarctic Survey)
By Sainan Sun
The inland of Antarctica is covered by thick ice of up to 4000 meters, which is accumulated over thousands of year. During this long term, ice is compressed in layers and we can get historical climate information from these layers.
Therefore, the internal structure and ice properties, as well as the basal properties are of glaciological and climatological interest. Ice-radar is a very useful tool for the study of glaciers and ice sheets. Nowadays, ice-radar is widely used in the study of Antarctica.
Radio-echo sounding techniques are based on the propagation of electromagnetic wave through the ice. A radar system contains the wave generator, the transmitting antenna and the receiving antenna.
The transmitter sends a pulse downwards and it is partially reflected at discontinuities and travels back to the surface, where the signals are detected by the receiver.
. Scheme of a radio echo radar measurement set-up, where transmitter (TX) and receiver (RX) are moved at a fixed distance across the glacier’s surface.
By Hugues Goosse
Our first camp was a temporary one so things were made relatively rapidly. The installation of the second camp was more elaborated and took also more time.
A main element in the planning of the camp is the wind. The different parts (tents, kitchen, containers with the material, skidoo parking) should be placed in the right way to provide shelter to the ones that are downwind but not inducing snow accumulation close to them.
Drone view of our camp (Photo Nader Wever)
For instance, all the tents are aligned in the direction of the dominant wind, with the opening of the tent in the direction opposite to the wind. A container is placed few meters in front of the tents to reduce wind speed close to the tent.
The main element to protect us from the wind is a two to three meter snow wall that was constructed with the snow tractors. This gives a bit the feeling of being in the middle of castle lost in the ice, but no night watch need to scouting at the top of this wall as we are in the South.
The snow wall that protects our camp from the wind
We also had to build a tent to protect the drilling system. This allows us to work when the conditions are not great.
It may seem strange but the main fear is not bad weather but melting. If the sun is shining directly on the drill, it can warm up and induce melting of snow that could then refreeze and perturb the system. A too high temperature is also of course not recommended to preserve the ice core.
We were then able to start the drilling December 19 after lunch. The first meters go quickly and it was already possible to collect 32 meters of ice on this first day. It will be slower as we get deeper but it is a very good start!
The first meters of the ice core
by Hugues Goosse
Unfortunately, the options are scarce. No web site is available to find the best accommodation for your needs. At least for us, it seems that the first choice is to sleep in containers.
You have the Novo Air Base way, where we were eight in a container, using our own sleeping bags on very soft mattresses.
The Princess Elisabeth station have rooms inside but now they renovate some parts and make new rooms. Consequently, we were put in containers, but they were much nicer, with good beds and clean sheets.
The exterior of sleeping room number 2 at Princess Elisabeth Station
And the interior
By Hugues Goosse
Nearly twelve days after leaving Belgium, we were able to make our first measurements at the location where the ice core drilling was performed last year.
The main objective was to measure the changes compared to last year to obtain estimates of snow accumulation at surface and ice movement.
Unfortunately, the camp location with our tents was about 30 km away from the drilling site. We thus had to commute every morning and evening by skidoo. As the surface was very rough and the weather conditions not always great, this took each time between one hour and a half and two hours.
Opening the drilling hole of last year that has been protected from the snow by a wood box.
by Hugues Goosse
The group has left Princess Elisabeth station after breakfast December 12. For the travel, we were installed in the kitchen we will use on the field.
The team just before leaving the Princess Elisabeth station
As we were sometimes shaken heavily on the rough terrain, all out belongings, the material had to be safely stored and the furniture fixed on the ground.
by Hugues Goosse
Even if we have 24 hours of light in this season, the temperature is higher at noon when the Sun is higher above the horizon than at midnight. Close to our camp, at the location of our weather stations, the difference between day and night is generally about 5 to 10 degrees.
Consequently, the ‘night’ can still be cold with temperatures well below -10°C. Nevertheless, as the Sun rises again and hits our individual orange tents, we are quickly boiling within our sleeping bags!
Figure from Quentin Dalaiden based on the dataset of Nicolas and Bromwich (2014)
In cases of a cold events like this one, you probably have heard people questioning global warming or calling for a temperature rise that would prevent us from such cold conditions. We know that having particularly cold or warm days is normal. It depends on weather conditions and is generally not at all related to climate change.
Nevertheless, a succession of warm events or a warming tendency can be the signature of the local impact of global changes. This is clearly the case in the Arctic where the large surface temperature increase and the melting of sea ice have been attributed to human-induced climate change without ambiguity.
The situation is different in Antarctica and the Southern Ocean. Since 1979 (i.e. since the beginning of reliable estimates based on satellite measurements), there were no clear trend in sea ice extent in the Southern Ocean. The Antarctic Peninsula and West Antarctica have warmed a lot since the 1950’s but not East Antarctica.
Climate dynamics implies that the current warming due to human activities should be smaller in Antarctica than in the Arctic1. We also expect large natural climate variations in Antarctica. The signal related to global warming has thus not yet clearly emerged from the range of natural fluctuations.
In other words, we do not know yet precisely which part of the observed changes in Antarctica are caused by human activities and which ones are due to natural variations of the system, calling for more studies in this important region for our planet.
1 The Southern Ocean includes a huge amount of cold waters. A lot of energy is required to warm it up. This energy is taken from the atmosphere, preventing a large warming of the air in contact with the ocean and more generally of the climate at high southern latitudes. Additionally, because of the dynamics of the Southern Ocean, the surface water that is warmed up by exchanges with the atmosphere is continuously transported to subsurface and replaced by colder water, amplifying the role of thermostat of the Southern Ocean.
By Hugues Goosse
I have asked and, at least for me, the answer is no. It is not unexpected as of course there is no antenna for standard telephone services in Antarctica.
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