EGU21-7284, updated on 30 Nov 2021
https://doi.org/10.5194/egusphere-egu21-7284
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Mapping the outdoor effective dose: the case study of the Umbria region (Italy)

Andrea Serafini1,2, Matteo Albéri2,3, Stefano Bisogno4, Enrico Chiarelli1,2, Luca Cicala5, Mario De Cesare5,6,7, Andrea Maino1,2, Michele Montuschi1,2, Andrea Motti4, Norman Natali4, Marco Ogna4, Kassandra Giulia Cristina Raptis1,2, Gianluigi Simone4, Virginia Strati1,2, and Fabio Mantovani1,2
Andrea Serafini et al.
  • 1INFN, Ferrara Section, Via Saragat 1, 44121, Ferrara, Italy
  • 2Department of Physics and Earth Sciences, University of Ferrara, Via Saragat 1, 44121, Ferrara, Italy
  • 3INFN, Legnaro National Laboratories, Viale dell’Università 2, 35020, Legnaro, Padua, Italy
  • 4Servizio Rischio idrogeologico, idraulico e sismico, difesa del suolo, Regione Umbria, Via Palermo 86/A, 06126, Perugia, Italy
  • 5Italian Aerospace Research Centre, Via Maiorise s/n, 81043, Capua, Italy
  • 6Department of Mathematics and Physics, University of Campania “Luigi Vanvitelli”, Viale Lincoln 5, 81100, Caserta, Italy
  • 7INFN, Napoli Section, Complesso Universitario di Monte S. Angelo, Via Cintia, 80126, Napoli, Italy

The absorbed dose rate due to natural radioactivity arises from terrestrial and cosmic sources, both contributing to the individual effective dose rate per fraction of time spent outdoor. Rocks and soils are the main reservoirs of terrestrial gamma-emitting radionuclides (e.g. 40K and radioisotopes of the 232Th and 238U chains) while high-energy particles originated from astrophysical phenomena produce a cascade of nuclear interactions which contributes to cosmic radiation decreasing in intensity with the atmosphere depth. Following the UNSCEAR 2008 report, the average exposure of the world population to the different natural radioactivity sources corresponds to about 2420 μSv/yr and the external effective dose of terrestrial and cosmic origin is 870 μSv/yr.

The Umbria region (Italy), with its high variability of sedimentary and igneous rocks (e.g. limestone, sandstone, volcanic tuff) and a population of about 880000 inhabitants well distributed between 100 m and 1000 m a.s.l., represents the ideal case for mapping the effective dose from natural sources in a multifaceted environment. The outdoor effective dose rate from terrestrial radionuclides is studied by analysing 7439 gamma spectra measuring rock and soil samples in laboratory and carrying out about 20 hours of airborne radiometric surveys. Collocated CoKriging is used for the spatial interpolation of the sparse data, adopting a high-resolution geological map as ancillary information. The obtained numerical map is integrated with the cosmic radiation effective dose rate calculated considering the effects of altitude, latitude and the solar magnetic activity cycle. The resulting map of the outdoor effective dose rate shows a median value of 632 mSv/yr and only 3% of the territory is characterized by values higher than 814 mSv/yr.

How to cite: Serafini, A., Albéri, M., Bisogno, S., Chiarelli, E., Cicala, L., De Cesare, M., Maino, A., Montuschi, M., Motti, A., Natali, N., Ogna, M., Raptis, K. G. C., Simone, G., Strati, V., and Mantovani, F.: Mapping the outdoor effective dose: the case study of the Umbria region (Italy), EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-7284, https://doi.org/10.5194/egusphere-egu21-7284, 2021.