New map for radioactive soil contamination in Western Europe
An international consortium of scientists has refined the map of caesium and plutonium radionuclide concentrations in soils in Switzerland and several neighbouring countries. Using an archive of European soil samples, the team led by Katrin Meusburger from the University of Basel, now at the WSL research institute, was able to trace the sources of radioactive fallout between 1960 and 2009. This study was published in Scientific Reports.
The study concludes that the caesium resulting from the nuclear tests - carried out in the stratosphere, i.e. at high altitude - circulated in the atmosphere before being brought down to the ground by the rains in a fairly homogeneous manner but with a slightly higher amounts in the rainiest regions, such as the Massif Central, the Ardennes or Brittany. On the other hand, the caesium released during the Chernobyl accident did not reach such altitudes; it remained at tropospheric level. The scattered rains that occurred in late April/early May 1986 quickly brought it back to the ground in areas where the plume from Ukraine had circulated. The spatial distribution of radioactive fallout is thus much more heterogeneous, with locally higher concentrations in Alsace, Franche-Comté and the foothills of the Alps, northern Italy and southern Germany.
The consortium consisted of geomorphologists, soil scientists and geochemists from the University of Basel (Switzerland) and the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), as well as the Fonds de la Recherche Scientifique (FNRS, Belgium), the Laboratoire des Sciences du Climat et de l’Environnement (LSCE - CEA/CNRS/UVSQ, France), the Joint Research Centre of the European Commission (Ispra, Italy), the Metropolitan State University of Denver (Colorado, USA) and the joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture (Austria).
Original text by the Laboratoire des Sciences du Climat et de l’Environnement (LSCE - CEA/CNRS/UVSQ, Institut Pierre Simon Laplace, Université Paris-Saclay) (Link)
Katrin Meusburger, Olivier Evrard, Christine Alewell, Pasquale Borrelli, Giorgia Cinelli, Michael Ketterer, Lionel Mabit, Panos Panagos, Kristof van Oost, Cristiano Ballabio
Plutonium aided reconstruction of caesium atmospheric fallout in European topsoils
Scientific Reports (2020), doi: 10.1038/s41598-020-68736-2