Emission Concentration ≠ Emission Rate. Measuring emissions in terms of mass rather than just concentration offers a comprehensive understanding of the total quantity of pollutants released into the environment. This approach captures the actual environmental load and potential impact of emissions, providing a clear picture of the pollution being contributed by a source. Concentration measurements alone, while useful for understanding the relative makeup of emissions, fall short of revealing the total volume of pollutants discharged. As environmental regulations and public health standards become increasingly stringent, quantifying the mass of emissions is crucial for compliance, environmental protection, and devising effective pollution control strategies. By focusing on mass measurements, organizations and regulators can make more informed decisions about emission reduction efforts and accurately assess progress towards environmental sustainability goals.

Emission measurement often involves analyzing flows that contain a mixture of gases, liquids, and sometimes solids, making it a multiphase flow problem. The presence of multiple phases complicates the dynamics of the flow, affecting how pollutants are transported, mixed, and eventually dispersed in the environment. Accurately measuring emissions in such conditions requires understanding the interactions between different phases to ensure precise quantification of pollutants.

In industrial or natural processes, emission is often mixed with other substances in a multiphase flow, therefore cannot be easily quantified with a single-phase flow meter alone.

The Advection Diffusion Model (ADM) provides a more comprehensive framework for emission measurement analysis because it captures the nuances of pollutant dispersion under varying atmospheric conditions and terrains. Unlike the Gaussian Plume Model, which assumes uniform dispersion patterns, the ADM accounts for changes in wind speed, direction, and atmospheric stability, offering a more accurate representation of real-world scenarios. This makes the ADM superior for detailed studies requiring precision in predicting pollutant concentrations over diverse geographical areas and complex environments.