BELATMOS: Monitoring Antarctica’s Atmosphere

Very few measurements of this type have been made thus far in Antarctica, especially inland where the composition may differ from coastal sites. It is important to evaluate concentrations and changes so that we can improve our understanding of how aerosols and trace gases are transported over long distances to Antarctica. Collected data is then used as input or validation of satellites and modeling samples.

Here are a few instruments used in the framework of the BELATMOS project:

• The sunphotometer measures the total extinction (attenuation) of sunlight by atmospheric aerosol particles at several wavelengths (from ultraviolet to infrared). When the signal is measured at two or more spectral lines, scientists can derive information to calculate the concentration of selected atmospheric gases, such as water vapor or ozone. Also information on the composition of the aerosol particles is available by analyzing the simultaneous signals at different wavelengths.
• The aethalometer measures the absorption of sunlight at several wavelengths by dark particles and gives information about atmospheric Black Carbon (= particles emitted from burning processes, such as from biomass burning, heating, power generation, etc.). Black carbon is thus a sign of global pollution and influences Earth's greenhouse effect.
• The Tapered Element Oscillating Microbalance (TEOM) with Filter Dynamics Measurement System (FDMS) measures the mass concentration of the ambient aerosol particles and the fine dust concentration. In Europe, it is used to set air pollution limits and take appropriate measures like traffic limitations. This instrument will be used to monitor Utsteinen's atmosphere during a long period and identify possible trends in the atmosphere.
• The Brewer Ozone Spectrophotometer is used to measure incoming sun radiations in the UV-A and UV-B bands as well as the total thickness of the atmospheric ozone column. Accurate measurements of the ozone column over Antarctica will help monitoring ozone layer's expected recovery. Ozone and aerosol particles have a big impact on the UV radiation received at the ground, which does impact flora and fauna.