You are here: Ozone, UV and Aerosol studies » Projects » BELATMOS
BELATMOS (RMI Contribution to the Belgian Antarctic station Princess Elisabeth)
Alexander Mangold, Hugo De Backer
Royal Meteorological Institute of Belgium
3, Avenue Circulaire
1180 Uccle
Contact: Alexander Mangold
The activities of the Belatmos project in Antarctica can also be followd via a blog.
Belgium has a long history of Antarctic exploration and scientific activities, dating back to 1897 and the first expeditions to Antarctica under the lead of Adrien de Gerlache.
At the occasion of the 1958 International Geophysical Year, Belgium organised a new expedition to Antarctica and set up the Roi Baudouin base at Princess Ragnhild Kyst. This base remained in activity for more than 10 years and allowed scientists to carry out essential research and observations in climate and geophysical sciences.
At the occasion of the International Polar Year 2007, the Belgian government decided to build a new scientific summer station in Antarctica and commited the International Polar Foundation to design and build this new base.
The new Antarctic base was built during the Antarctic summers 2007/2008 and 2008/2009 and the first scientific activities started in January 2009. In the summer season 2009/2010 the station received the finishing works and a powerful satellite dish. The Princess Elisabeth station is situated north of the Sor Rondane Mountains in Dronning Maud Land, East Antarctica, on the small, granite Utsteinen ridge (71º57’S, 23º20’E, 1390 m asl).
In 2006, the Federal government has assigned 3 millions euros to the Belgian Science Policy (BELSPO) for the management and research programme at the new scientific summer station in Antarctica.
The Royal Meteorological Institute, in collaboration with BISA and Ghent University, has proposed to carry out observations on the composition and chemistry of the atmosphere at the Antarctic base. The proposed project would bring important contributions to the monitoring of ozone and minor trace species in the atmosphere as well as the characterisation of aerosols in the atmosphere. The project has been formally approved by the Belgian science policy authorities in summer 2008.
Short description of BELATMOS:
The objective of the project is to contribute to the long-term monitoring of the chemical and particle composition of the Antarctic atmosphere and to the quantification of the UV radiation reaching the surface, using a suite of complementary ground-based instruments.
Atmospheric aerosol particles, ozone and other trace gases are linked to climate change through various complex feedback mechanisms. The Antarctic (also as the Arctic) is a very sensitive region for the world’s climate. Atmospheric composition measurements at a remote place like Antarctica are important to evaluate changes in background concentrations and to improve our understanding of long-range transport of aerosol and trace gases. Although being a remote region, Antarctica is influenced by pollution and natural aerosol from lower latitudes (e.g. biomass burning, volcanic eruptions) or by the research stations themselves. There are only very few measurements of this type in Antarctica, especially inland, where the composition may be different from the coastal sites which have more marine type of aerosols. However, such kind of data is highly needed for input or validation of data from satellites, or global models.
Ozone is a key atmospheric gas and has a large impact, amplified or compensated by the presence of aerosol particles, on the UV radiation received at the ground. The amount of biological damage to sensitive Antarctic marine organisms, other ecosystems and human health due to increasing UV radiation is therefore directly related to the level of ozone depletion and atmospheric aerosol content.
In addition, more and accurate measurements of the ozone column over the Antarctic continent are important. The so-called ozone-hole occurs since over 20 years now each year over the Antarctic during springtime. Although the production of halogen species responsible for the ozone destruction has been stopped after the Montreal Protocol, the first clear evidences for a recovery of the ozone layer are still awaited.
The proposed instruments include as primary instruments an aethalometer, a CIMEL spectrophotometer, and a Tapered Element Oscillating Microbalance (TEOM). In a second stage, an ultra-fine Condensation Particle Counter, a Particle Sizing Spectrometer, a UV Brewer spectrophotometer, a nephelometer and a set of three pyranometers (UV-A, UV-B and total solar radiation) and a multi-axis UV-visible DOAS spectrometer (MaxDOAS) will be very valuable complementary instruments.
The instruments are all designed for unattended operation in remote places, which means they require little maintenance. Hence, despite operations will be first limited to summer months according to the functioning of the station, whole-year continuous long-term monitoring can and will be envisaged in a later stage. The analyses will also use meteorological parameters, such as the wind direction, wind speed, temperature, pressure and humidity to be measured by a weather station installed close to the instruments.
Current installation, results
During the BELARE 2008-2009 expedition, the first two instruments were installed: the CIMEL sunphotometer measuring the total extinction of sunlight at several wavelengths (from UV-B to near-IR), and an aethalometer measuring the absorption of sunlight (extinction = absorption + scattering) at several wavelengths (also from UV-B to near-IR). Also information about the aerosol type is possible with this information. The aethalometer measures also the concentration of light-absorbing particles, which is a proxy for particles from incomplete burning processes (biomass burning, heating, power generation,...). The sunphotometer has been installed on the roof of the main station roof and the aethalometer in an shelter south of the main station, with the air inlet on the top of that shelter.
During the season 2010-2011, 2 instruments were installed in addition: (i) a Brewer ozone spectrophotometer (roof main station), measuring the total column amount of ozone and the UV radiation between 280 and 340 nm, and (ii) a Tapered Element Oscillating Microbalance with Filter Dynamics measurement system (TEOM-FDMS), measuring the total mass concentration of aerosol particles (shelter south).
The average aerosol optical depth (AOD) measured by the Sun photometer was 0.02 at 500 nm, indicating a very low atmospheric aerosol load. With the aethalometer, very low concentrations of light-absorbing particles were observed (average of 5.9 ± 5.5 ngm-3). From the aethalometer measurements also the aerosol absorption coefficient was derived (average of 8.7x10-6 ± 7.4x10-6 m-1). Simultaneous measurements of the aerosol total mass concentration by the TEOM-FDMS (average of 3.5 ± 3.4 mgm-3) gave an estimate of the fraction of absorbing aerosol (approx. 0.2%).
In austral summer 2011-2012, a set of additional 4 instruments will be installed. On the main station roof sensors for UV-A, UV-B and total solar irradiation will be installed. In the southern shelter three new aerosol instruments will be installed: (i) a Laser Aerosol Spectrometer, measuring the number concentration of particles in several size classes from 90nm to 7.5 micrometers, (ii) an ultrafine condensation particle counter, measuring the total number concentration of particles in the size range from 3nm to 3 micrometers, and (iii) a nephelometer, measuring the total scatter and the backscatter of particles at three wavelengths (450, 525, 635nm).