The project EURAMET BIOSPHERE, instrumentation development and atmospheric measurements

The European Partnership on Metrology (EPM) joint research project BIOSPHERE aims to develop the necessary instrumentation, methods, and measurement infrastructure to assess how the increasing ionization of the atmosphere, caused by extraterrestrial radiation fields (cosmic rays and solar UV radiation) and amplified by anthropogenic emissions, affects the human and ecological health of our planet.

Both electron precipitations of extraterrestrial origin and energetic bursts of protons released from the sun during solar flares or coronal mass ejections have the potential to affect lower stratosphere ionization and interfere with catalytic ozone depletion reactions. This can lead to an increase of the biologically active UV radiation flux, with significant implication for ecosystems, plants and human health, like cancers and cellular dysfunctions. 

To estimate the impact of these extraterrestrial radiation fields on the biosphere, the EPM project BIOSPHERE will provide traceable metrological data on cosmic ray fluxes, UV solar radiation at the earth surface, and the total ozone column which are key to assessing the role of cosmic rays in the atmospheric dynamics. For this purpose, dedicated instrumentation for determining the dependence of secondary cosmic rays (SCRs) on primary cosmic rays (galactic cosmic rays, solar particle events) and atmospheric parameters (e.g., temperature, density and aerosol concentration) has been developed and characterized. This instrumentation measures the SCR flux rate during measurement campaigns, side-by-side with spectra of UV solar radiation at ground level and total atmospheric ozone, with the aim of identifying and correlating changes of extraterrestrial cosmic radiation (revealed with SCR fluxes increased) with changes in atmospheric parameters (ground-based UV radiation, total ozone column). As the cosmic ray flux measured at ground level is influenced by the overlying atmosphere, a metrological methodology is currently being developed to correlate SCR flux rates with temperature and pressure. This method will also help to quantify the rates of ionizing particles in the lower stratosphere that can interfere with catalytic ozone depletion reactions. Traceable measurements of cosmic ray fluxes, UV radiation spectrum and ozone column are being carried out in measurement campaigns at four European sites. We will present here the instrumentation developed, the instrumental methodologies and the results of the first two campaigns.