Global Mercury Footprint Evaluation using a Geographical Pollutant Propagation Model

Abstract

This work presents a method for the accurate evaluation of the footprint of chemical pollutants on a global scale. An extension of the standard pollution propagation models is proposed to calculate the chemical footprint efficiently. The proposed improvements overcome the current modelling and enable the evaluation of the directed transport of chemicals with water or air flows. The current research introduces several model modifications to account for the directed pollutant transport with global water flows and selects the Jacobi solution method for the resulting large-scale system of mass transfer equations. The model was combined with geographic information system data to account for the geographical propagation of the pollutants. The proposed method is implemented in Microsoft Excel using the built-in Visual Basic for Applications programming language. The method is tested on the example of evaluating the Global Mercury Footprint. As a result of the work, a tool was obtained that allows estimating the chemical load for the entire World, taking into account the transfer of chemicals with water flows. In the future, this tool can also be used to support regulatory decisions, for example, to assess the effect of mercury immobilization in solid waste on the mercury footprint.