A new paper on using optimal transport for the verification of simulated and observed plumes of pollutant has been published in Tellus B: Using the Wasserstein distance to compare fields of pollutants: application to the radionuclide atmospheric dispersion of the Fukushima-Daiichi accident. It can be accessed online. The Wasserstein distance is a non-local metric based on minimal field displacement. We apply this measure of verification to simulations and data of the atmospheric radionuclides dispersion of radionuclides that followed the Fukushima-Daiichi disaster in March 2011. We have developed and optimized a python code using the algorithm by Papadakis, Peyré, and Oudet. It is freely available here. This paper is the result of a collaboration between Ecole des Ponts ParisTech and The Institute for Radiological Protection and Nuclear Safety (IRSN).