Atmospheric Dispersion Modelling

Question 1

What are atmospheric dispersion models used for?

Answer 1

Compliance with air quality guidelines, planning of new facilities, managing existing emissions, identifying the source of existing problems, risk management, saving money

Question 2

4 stages of modelling process

Answer 2

Data input, data processing, data output, data analysis

Question 3

Source geometries

Answer 3

Point, area, line, volume source

Question 4

The pollutant source

Answer 4

Emission rate, height of emission, temperature of emission, exit velocity of emission

Question 5

Importance of wind speed and direction

Answer 5

Wind speed is most important tor line and point sources. Wind direction is most important for point sources.

Question 6

Steady state Gaussian plume models - aermod/ausplume

Answer 6

Somewhat limited in scope and results. Single input requirements and easy to use, not so good in light wind conditions, are not applicable to regional scales, complex terrain or changeable meteorology

Question 7

CALINE - 4

Answer 7

Designed specifically for predicting air quality in the vicinity of roads taking into account the vehicle fleet and the meteorology. VEPM provides input into his model

Question 8

Lagrangian models

Answer 8

Complex models. Con be used for different scales and sources, non steady-state ( can account for changes in meteorology ). Can Handel complex terrain and atmospheric chemistry. More complex data input needed. Good in low wind speed conditions. Becoming more commonly used for regulatory purposes.