5. CASE STUDIES FOR THE EVALUATION OF THE SRSM AND THE SRSM-ADIFOR

This chapter presents four case studies to evaluate the SRSM and the SRSM-ADIFOR. These models cover a range of applications, both from the perspective of model application (such as biological, air quality, and groundwater) and from the perspective of model complexity (ranging from a zero dimensional model to a three-dimensional urban/regional scale photochemical model). The execution times of the models also vary from a fraction of a second to a few hours per model run. The main objective of these case studies is to evaluate the applicability of the SRSM and the SRSM-ADIFOR to a wide range of transport-transformation models, and potentially to numerical models used in other areas.

The case studies are presented here in the following order:

I:

A zero-dimensional pharmacokinetic model.

II:

A two-dimensional atmospheric plume model.

III:

A three-dimensional urban/regional scale air quality model.

IV:

A one-dimensional ground water model with discontinuous probability density functions.

The order corresponds to both the chronological evaluation of the SRSM method, as well as to the associated complexity. The computational time for each model simulation in the first three cases is of the order of a fraction of a second (case I), through a few seconds (case II), to approximately 6 hours (case III). The groundwater model required about a few seconds per model simulation, but is presented at the end, since the complexity with respect to the specification of uncertainties in inputs is high.

Each case study description contains the information about the model and its application in exposure/risk assessment. Then, the uncertainties associated with the model are described, and the application of different uncertainty propagation methods is presented. The estimates from the uncertainty propagation methods are then presented graphically, in the form of probability density functions (pdfs), along with a brief discussion at the end.