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The MODERN model is free and public. We believe that a transparent and easily modifiable model would promote the application of FRN to assess soil erosion under different conditions.

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When using the file, users automatically agree to cite the following paper if MODERN is used for published research.
Arata, L., Meusburger, K., Frenkel, E., A’Campo-Neuen, A., Iuran, A.R., Ketterer, M.E., Mabit, L., Alewell, C., 2016. Modelling Deposition and Erosion rates with RadioNuclides (MODERN) - Part 1: a new conversion model to derive soil redistribution rates from inventories of fallout radionuclides. Journal of Environmental Radioactivity, 162, 45-55.

Acknowledgements
This work was funded by the Swiss National Science Foundation (SNF), project no. 200021-146018. The authors also acknowledge the International Atomic Energy Agency (IAEA) for support provided through the technical project 20435 and the Coordinated Research Project (CRP) D1.50.17 on “Nuclear techniques for a better understanding of the impact of climate change on soil erosion in upland agro-ecosystems”.

Project Information SNF Nr. 146018

To efficiently mitigate and control soil lossesby erosion suitable methods for comprehensive data generation on the magnitude and spatial extent of soil erosion are needed.

Artificial radionuclides such as ¹³⁷Cs and ^239-240Pu, which originated from thermonuclear weapon tests in the 1950s-1960s and nuclear power plant accidents (i.e. Chernobyl), can be used for this purpose, because they are rapidly and strongly adsorbed to fine soil particles with limited migration and bioavailability. Documenting the subsequent radionuclides redistribution, which move across the landscape in association with soil/sediment particles primarily through physical processes, represents an effective means of tracing rates and patterns of erosion and deposition. In addition, to these artificial radionuclides we also explore the applicability of the natural geogenic radioisotope excess 210-Lead in our alpine study sites.

The fallout radionuclide (FRN) approach possesses important advantages over more conventional means of documenting soil erosion and soil redistribution (such as plots or field mapping), because a single field visit is sufficient to assess the net soil redistribution since the main FRN fallout. Further, FRNs comprise all erosion process and is thus of particular interest in the context of quantification of snow induced erosion.

However, the time-averaging nature from the main period of bomb fallout to the time of sampling can also be considered as limitation of the approach. To meet the requirement of short-term assessment (e.g. several years instead of decades) and monitoring in light of increasing concern for the impact of changing land use and climate we explore the applicability of resampling and repeated sampling techniques (Figure) in the frame of the Coordinated Research Project (CRP) Nuclear Techniques for a Better Understanding of the Impact of Climate Change on Soil Erosion in Upland Agro-ecosystems funded by the International Atomic Energy Agency (IAEA).

On-site quantification of soil erosion with FRN, in combination with the off-site tracking of sediments using fingerprinting techniques complements our soil erosion modelling based assessments and as such enhances our understanding on the spatial and temporal variability of erosion.