Profiling time varying aerosol sources from distant measurements
Abstract
Characterizing aerosol sources emission profiles is a central problem in risk prevention, although it is very tricky to achieve in practice. When concentration measurements are available in the far-field, this can be done indirectly through the use of so-called inverse methods. Thus M. Girault et al (Girault, Maillet, Fontaine, Braconnier, & Bonthoux, 2006) have adapted some techniques originally developed for thermal problems in the case of a gaseous pollutant emitted by an unsteady source. The approach has proven itself successful, and we propose in this paper to extend its scope to aerosol pollutants emitted. The evaluation procedure of aerosol emission is based on the use of a mathematical algorithm which allows reconstructing the emission rate by inverting a relationship (called impedance) linking the aerosol source and concentration measurements. This procedure includes two distinct steps. The first step consists in determining the impedance using a known source of aerosols and the corresponding dust measurements. In a second step, an unknown source of aerosols is reconstructed from the model inversion and dust measurements.