In atmospheric dispersion modeling, which model is primarily used to address transient releases?

The puff model is primarily used to address transient releases because it is specifically designed to simulate the dispersion of releases over a short time period. This model represents the emitted material as a series of discrete "puffs" that are released into the atmosphere. Each puff is treated as a distinct mass of pollutant that spreads out over time due to atmospheric turbulence and diffusion processes.

This approach is ideal for transient or time-varying releases, such as those from industrial accidents or emergency situations, where the emission rate can change rapidly and the behavior of the plume can vary significantly within a short timeframe. Since the puff model can accommodate fluctuations in the release rate and the varying atmospheric conditions, it provides a more accurate representation of how pollutants disperse during these transient events.

In contrast, the Gaussian model is typically used for continuous or steady-state releases, where the emission rate remains constant over time. The plume model is also geared towards more stable conditions and longer-term releases. The box model, while useful for analyzing average concentrations over a defined volume, does not effectively capture the dynamics of short-duration or variable emissions.