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.