Sunday, 10 December 2017

Work and life at Princess Elisabeth Station

the CHASE team plus Jacques from Canada (oups, from Quebec)

It is now the 18th day that I am at Princess Elisabeth station. We arrived on Thursday 23rd November in the evening and since then I have been busy with a lot of things. The first two days we – the group of scientists which who I am right now here- got various trainings – from medical to skidoo driving and mechanics, handling a GPS, finding a waypoint and following a route, to rope techniques and rescuing somebody out of a crevasse.

From Sunday 26 December on I had time to look after the many instruments I am here for. It was and it is quite a full agenda. In the aerosol instrument shelter three of the five instruments are running again after checks, maintenance and calibration (the Aethalometer, the Nephelometer and the Laser Aerosol Spectrometer). The TEOM-FDMS and the Condensation Particle Counter (total mass concentration and total particle number, respectively) are not working and after several unsuccessful checks I will most probably have to take them back with me for profound repair. The Brewer ozone spectrophotometer is up and running again. The total ozone column is around 300 to 330 DU, a normal value for this time and sign that this year’s ozone hole filled up rapidly. The UV index maximum per day is around 5, once we were touching 6. Also up and running are the sensors for total solar radiation and integrated UV-A and UV-B radiation. Total solar can reach up to 1000 W/m2 around noon these days. The Sun photometer has been re-installed and it is working nicely again, as well as the MAX-DOAS instruments of the Space Aeronomy institute. I have also checked and maintained the instruments for cloud and precipitation detection – the ceilometer, micro-rain radar and pyrometer (see also www.aerocloud.be). This season we are in addition installing a second micro-rain radar (from University of Bonn, Germany), in order to compare with ours. Friday late evening we had a short real snowfall event when for around 30 minutes low clouds passed our station. IPF has also put online a description of the Aerocloud project - see here.


In order to save energy, space, cabling and to assure a higher security to access the IT infrastructure of the station, I am also busy, together with Johnny and Thomas, to migrate one instrument after the other to a virtual machine on a central server. This way, our dozens of laptops and desktops get obsolete, access is safer and better controlled and energy demand during winter will be much less. However, if it sounds easy to install some software on a server, it is in practice more complicated to install the instruments with their individual communication needs and wishes.

And further, I am also busy with the new project, CHASE, to collect particles on filters. Nadine and Christophe have been very busy to install many passive samplers at and around PE station (see their posts on www.bncar.be). Together, we have also installed three pumps for the active sampling of particles on filters. Johnny helped us a lot to install tubings, pumps, inlets in and on the new ‘Atmos’ shelter. When Nadine and Christophe left to the coast in order to install there several passive samplers, I started the first filter samples with the pumps on 6 December. They will run 7 days continuously in order to collect enough mass for the analysis in the labs. It is another story to prepare clean filters and install them clean.

the shelter, inlets of the active sampling of atmospheric particles, with station in background

Although this is my seventh time at the station, it is still and again exceptional. The landscape is magnificent, the horizon wide, light, clouds and sky are in steady beautiful change and the feeling being far away from the next settlement with human beings (Russian station Novo at 450 km and the Japanese station Syowa at 650 km) gives rise to think about yourself. And also living together in a group in this special environment adds to the unique experience. In the beginning we were 27 altogether at the station, now we are with 10, the others left for glaciological research towards the ice shelf near the coast, others in order to unload the ship with containers destined for all kind of filling up stocks of the station. With ten – life at station is much quieter, everybody is doing his job during the day and the daily duties like kitchen aid, cleaning rooms, etc is taken over by one or the other, no plan is necessary. In the evenings we sit also often together and talk, discuss,… There are also moments when one can have time for himself, e.g. after lunch for half an hour or in the evening or on Sundays when work pressure is less. I sit often late evening in the ‘tower’ where several of my instrument-pc’s are located for supervision, but then I sit there because of the pretty view to both the mountains and the wide white ocean of ice and snow. And the light in the evening, when the sun is behind the Utsteinen nunatak is very different from the time during the day-hours. Often snow petrels are then sailing over the Utsteinen ridge and because of they are higher up, they shine brightly in the sunlight. It makes you think, enjoying and watching these birds sailing in the cold wind.

Tuesday, 21 November 2017

Departure to Antarctica


Finally, after one week waiting we got the news that we will leave Cape Town direction Novo Air Base on Wednesday night. We should depart around 23:00 local time and land 5h45 later at the Russian Air Base. In fact, from last Friday late afternoon to Tuesday morning, the weather at Novo was not favourable to fly, it was stormy with precipitation. And before the aircraft can fly to Novo and land there, the staff of Novo has to free the 3km runway from the precipitated snow, clean and prepare it. This is an immense work and takes its time. We are all happy here to know that and when we finally will depart and that we will soon be able to start our planned programmes around Princess Elisabeth station.

Saturday, 18 November 2017

Cape Town



I arrived in Cape Town on Tuesday 22:30 local time (GMT+2). With me there are Nadine from ULB and Christophe from UGent for our CHASE project; Frank and Jean-Louis of ULB, Stef of TU Delft, TJ of Taiwan and Emmanuel and Etienne from Canada, all six for the Mass2Ant project; Henri our bird expert (Natural Sciences Institute/museum); Jacques the station’s doctor and Daniel (field guide) from Switzerland; and finally Baptiste, Olivier (BE) and Jacques (CAN) completing the station’s staff. 

Unfortunately, our flight to Antarctica is delayed. Mainly due to bad weather in Antarctica, also the planned flights before us encountered delay and this delay has to be recovered to bring in all the waiting teams of the different research stations. The unfavourable weather will persist at least until Tuesday. So, we will fly only by Wednesday to Antarctica. Hopefully. Almost one week of delay will put pressure on our and the station’s staff time schedule at Princess Elisabeth station. 

view southwards from Cape of Good Hope
 
Meantime, we are preparing what could nevertheless be done from here – collecting the polar clothing from IPF and checking that we do not forget any small item for the equipment and project. But of course we are also enjoying Cape Town, its pleasant weather and the surroundings. Yesterday, on Friday, we hired a car and drove to the Cape of Good Hope (the most south-westerly point of Africa). On the way there, we stopped at Boulders Beach were a colony of around 2000 African Penguins (Sphenicus demersus) lives. It is the only species breeding in Africa and it is listed as an endangered species. 

 Scientists at Cape of Good Hope
 African Penguins

Sunday, 22 October 2017

New research season ahead

This winter – or better summer in the Southern Hemisphere – our research at Princess Elisabeth station will restart. Besides the AEROCLOUD project, for which I will leave to Antarctica, there are three more scientific projects, in which colleagues of the Royal Meteorological Institute (RMI) are involved: CHASE, GEOMAG and MASS2ANT. The expedition is organized by the Belgian Polar Secretariat and its operator, the International Polar Foundation.

As described before, within the AEROCLOUD project (financed by the Belgian Science Policy Office programme BrainBe), the RMI collaborates with the Catholic University of Leuven and the Belgian Space Aeronomy Institute in order to investigate relationships between aerosol, clouds, precipitation and climate in Antarctica. Aerosol particles are necessary for the formation of clouds, which transport the necessary humidity to Antarctica for precipitation, which in turn is the only way how the Antarctic ice sheet is gaining mass. Our range of up to 15 scientific instruments is quite unique in Antarctica and the gained data will serve to improve regional climate models in order to better understand how the Antarctic ice sheet will behave in a changing future climate. This season, I will leave Belgium mid-November and I will stay until 20 December at Princess Elisabeth station.

The almost five weeks will be filled with the maintenance and calibration of the aerosol, cloud and precipitation instruments. The instruments could in general operate whole-year round, but they have been without power since my last post. Therefore, I will be busy with a lot of checks if the instruments are working properly and I hope that not too many repairs will be necessary and that there will be no serious damages. In addition, I will re-install the Brewer ozone spectrophotometer and the Cimel Sun photometer on the roof of the station. The Brewer is important to monitor the evolution of the total atmospheric ozone column (this year’s ozone hole appears to be a relatively ‘smaller’ one; link) and the incident UV-A and UV-B radiation. The Cimel measures the extinction of the solar radiation by particles. Further, I will restart together with colleagues and the station staff the weather balloon launches in order to derive vertical profiles of temperature, humidity and wind by radio soundings.


AEROCLOUD is not the only project I will be working on. There is also the CHASE project (financed by the Belgian Science Policy Office programme BrainBe), in which my institute and I are collaborating with the University of Ghent (UGent), the Université Libre de Bruxelles (ULB) and with the Vrije Universiteit Brussel (VUB). Two colleagues, one of UGent and one of ULB will stay during the same period as I at Princess Elisabeth station. Within CHASE we face the challenge to study the chemical composition of atmospheric particles, collected on filters and within surface snow. We want to analyse both the organic and inorganic composition as well as conducting isotopic analyses on the samples. Because the overall aerosol amount in the Antarctic atmosphere is very low, we will apply pumps which generate a very high air flow rate (more than 300 L/min) which will be maintained over several days for one single filter sample. This is in order to gather enough mass on the filters to guarantee a sufficient signal-to-noise ratio in the analyses. With the results we will get more insight on the relative importance of, e.g., trace elements, (persistent) pollutants or micro-nutrients like iron. The chemical signature of the collected aerosol will help us also to identify the potential source regions (e.g., Southern Ocean, South Africa or South America) and the relative importance of natural against anthropogenic sources.


Further, there is another scientific project of RMI going on at Princess Elisabeth: GEOMAG. Within this project (financed by the Magnetic Valley initiative of the Belgian state), the RMI is installing a 100-% automatic ‘magnetic’ observatory in Antarctica, complementing an international network of respective observatories (INTERMAGNET). It will be the first complete observatory in an uninhabited environment. The infrastructure and two instruments have already been installed in February 2015. In February 2018, two colleagues of RMI (from our department in Dourbes) will install the ‘GyroDIF’, which measures automatically the absolute magnetic field, the reference value for the more routine measurements of the variations of the magnetic field.

Finally, there is the project MASS2ANT (financed by the Belgian Science Policy Office programme BrainBe), in which the Universit√© Catholique de Louvain, the Universit√© Libre de Bruxelles and RMI are working together. MASS2ANT aims to investigate the local processes responsible for the variation of the surface mass balance in the Princess Ragnhild coastal region and also to document the changes during the last 300 years by drilling ice cores. Furthermore, the project wants to establish links between local processes and processes at larger scale with the help of combining and linking models of different scales (both in temporal and spatial resolution). This will enable to get a better understanding of the surface mass balance variation at larger scale. 

Friday, 1 July 2016

In freezing mode



Finally, we have not been lucky this austral winter. On 21 May, there was a huge storm, with hourly averages of wind speed up to 27 m/s and 6-min-peaks up to 38 m/s. In the course of this storm, the communication link to the stationwas interrupted and could not be restored (if the storm has been the cause can’t be confirmed, however). Also other satellite communication means did not work anymore, indicating that the station had also lost power. The reasons are not clear (as there is no communication link to explore…). So, this means that everything is now in ‘freezing’ mode. Inside the station and in the scientific shelters, there should be no issue for the instruments – it should be dry and relatively ‘warm’. However, the power outage means also that there is quite a lot of maintenance work to be done when the next BELARE campaign starts in November this year. In particular, the instruments which are installed on the roof of PE station have to be checked in detail. Last year, when everything operated without interruption during winter, it was much less maintenance work. We also hope that the instruments have not encountered damage during that huge storm, and also that the long time they will be now outside without being powered will not lead to damage. Only by mid-November, when the first team arrives at PE, we will know more details. Until then, we hope the best.

In the meantime, there is some time to go ahead with some data analysis. Below, a graph for the monthly means of the total particle number concentration is given, for all years/months available up to now. There are several striking points : a) there is a clear yearly cycle, with relatively high numbers  during summer and lower particle numbers during winter, b) winter numbers (May, June, July) are extremely low (down to some tens of particles per cm3), c) as soon as sunlight returns in spring (Sep, Oct), numbers go up distinctly, d) monthly numbers are well repeated each year, however with some annual variation, e) especially from November throughout March, the statistical means come with very high standard deviations. Some  explanations : during the summer months, transport of air masses from lower latitudes or the coast to PE station is more often than during winter when the strong atmospheric circular circulation around Antarctica (polar vortex) is forming a quasi- barrier for this kind of transport. In addition, there is also (almost) no sunlight which could trigger particle formation processes by atmospheric photochemistry. In September, October, sunlight returns, and also the polar vortex is becoming less stable, setting the scene for atmospheric particle formation and transport. The high standard deviations were caused by short-termed events (some hours to one day), during which the particle number increased from 200/300 per cm3 up to 6000 per cm3. Such events can be linked to either entrainment from the free troposphere and/or the passage of clouds with or without precipitation.

Wednesday, 6 April 2016

Successful season behind and promising winter season ahead



In the meantime we are already in April. High time to post something on the blog. The BELARE 2015-2016 expedition at Utsteinen has been finished end of February when the last team left Princess Elisabeth station. The expedition season has been successful for our project. All instruments for year-round operation have been maintained and are still operational.This means that now an un-interrupted time series exists from November 2014 to present for four aerosol instruments (aethalometer, nephelometer, TEOM-FDMS, U-CPC). The laser aerosol spectrometer has been re-installed after its repair and has been operational since December 2015 – and is still running. The Brewer ozone spectrophotometer could measure the whole austral summer season until mid-February when it had to be dismounted as usual. Below there is a graph showing the time series of total atmospheric column ozone from end of November to end of December 2015. It illustrates nicely the period until mid-December when ozone hole conditons (i.e. total ozone below 220 DU) persisted over the region of Utsteinen. Normally, such conditions persist only until end of November, beginning of December. The ozone hole of 2015 was indeed one of the most stable one on record. 
 
time series of total ozone end of Nov-2015 to end of Dec-2015

the MAX-DOAS (left) and the sunphotometer (right) instruments on the roof of PE station

The next image shows the sunphotometer (to the right) and the new-comer instrument ‘MAX-DOAS’ (to the left). The MAX-DOAS (Multi-AXis Differential Optical Absorption Spectroscopy) system is part of the BIRA contribution to the AEROCLOUD project. This instrument will monitor the vertical distribution of aerosols as well as several trace gases present in the atmosphere above the station. Like the Brewer, the MAX-DOAS measures the spectrum of solar light attenuated and scattered by atmospheric particles and molecules, in the wavelenght region of 300 to 550 nm, where a number of atmospheric molecules such as ozone and other compounds (NO2, BrO, OClO, H2O, O4) can be detected. By scanning the sky from the horizon to the zenith, the instrument provides information on the vertical profile of these molecules, as well as on aerosols which affect the measured trace gas absorption. First measurements are very promising and comparisons with the Brewer instrument (total ozone) and the sunphotometer (aerosol optical depth) show good agreement. In particular interesting is , that the instrument will continue its monitoring throughout the year. Therefore (if it keeps on running), it will be possible to observe the onset of the ozone hole as soon as the light starts to illuminate the polar stratosphere in early austral spring.. In addition, the concentration of several ozone related species (NO2, BrO and OClO) will be simultaneously measured providing an ensemble of data to characterize the chemical evolution of the polar stratosphere during the spring period. 

 the new instrument 'Snowflake Video Imager' on the roof of PE station

Our partners from the KU Leuven installed in January 2016 also a new instrument on the roof of the station, the ‘SnowflakeVideo Imager’ (see third image), designed by NASA. It contains a high-speed camera with sufficient frame rate, pixels, and shutter speed to record thousands of snowflake images in an undisturbed flow. These images are used to derive information on precipitating and blowing snow particle size distribution, as well as information about particle shape. This information on snow particles is important for correct estimation of snowfall amounts based on the radar measurements. A nice test for the instruments has been an impressive storm on 29 and 30 March 2016, with wind speeds around 20 m/s, peaking up to 26 m/s and after which the automatic weather station detected a snow accumulation around 20 cm. When writing this post, just another storm is active in the area of Utsteinen. So far, the instruments cope well with these conditions and the aerosol instruments are well in their cosy shelter (fourth image) – outside storm and very low temperatures, inside around 20 °C. 

inside the aerosol instrument shelter during winter season