Comparison of Gaussian Plume Model and Lagrangian Particle Model for the Application of Coastal Air Quality Modelling

Rajib Pokhrel,Heekwan Lee

doi:10.11648/j.ajere.20190404.16

Abstract

Incheon is one of the biggest cities located in coastal region where small to big size industries, Incheon sea port, Incheon airport, etc are in operation. The air pollution dispersion from those sources has been major concerns for Incheon coastal area where air emission, dispersion and deposition have been studied using different approaches of monitoring and modeling. Essential meteorological data were acquired by field monitoring and from the published data. GTOPO30 (global digital elevation model with a horizontal grid spacing of 30”) was used as terrain data for AERMOD and USGS 30” resolution terrain data was used in A2C flow/A2C t&d model. Steady state Gaussian plume dispersion based model, i.e. AERMOD, and Lagrangian puff dispersion based model, i.e. A2Cflow/A2Ct&d models, were accomplished by introducing the local meteorological and geographical information to test the performance of models around the unsteady air flow area. AERMOD simulation results showed that the pollutants from the source are transported and dispersed around the sources similar to the average wind flow direction. There was no significant difference in pollutants dispersion regardless of land breeze or sea breeze conditions. On the other hand, the results from Lagrangian puff model showed that the puffs transport, and dispersed around the coast area followed the sea/land breeze pattern. The comparative analysis of pollutants deposition estimated by steady state Gaussian plume model and Lagrangian puff model showed that the Gaussian plume model underestimate the pollution dispersion quantity at the onshore site during day time and overestimate during late night to early morning. Hence the Lagrangian based model is recommended for estimating pollutants dispersion and deposition around the unsteady air flow region.

Highlights

With the advent of industrial revolution and later advent of automobiles, the air quality of most large urban and industrial areas took a nosedive with the rise of airborne particles, black shoots, smog, etc the air pollution became a serious problem for large cities and commercial centers at early stage
When the sea/land breeze index of 3.0 is applied for Incheon area, frequent sea breeze events are found in late spring to summer season
The Automatic Weather Station (AWS) data confirmed that the majority of wind blows from NNW, N, & NNE during the autumn and winter season, SW & NNW during the spring and SW during summer season

Summary

Introduction

With the advent of industrial revolution and later advent of automobiles, the air quality of most large urban and industrial areas took a nosedive with the rise of airborne particles, black shoots, smog, etc the air pollution became a serious problem for large cities and commercial centers at early stage. Long-term exposure of humans to non-lethal air pollutants and the effects of air pollutants on global and regional atmospheric cycles were studied intensively [1]. Urban air pollution in the form of urban plume is transported by atmospheric wind to rural pristine and wilderness areas far away from its source region. Many rural and agricultural sources as well as natural sources located within and outside the region contribute to the regional air pollution [2]. The pollutant transport, dispersion and deposition characteristics directly and indirectly depend on the pollutant species, surface topography, local and regional meteorology, etc. [2,3]

Methods

Results

Conclusion