High–resolution pollutant transport in the San Pedro Bay of California

Alexander Cohan,Jun Wu,Donald Dabdub

doi:10.5094/apr.2011.030

Abstract

The combined sea port of Los Angeles and Long Beach in California constitutes the second busiest port in the United States by shipping volume. Communities near the ports face environmental justice concerns from a variety of sources including roadway and port related activities. This study examines the transport and diffusion of PM2.5 and NOX in port communities using the high–resolution plume model AERMOD, incorporating surface and aloft observed meteorology and local topography. Pollution impacts of roadway related emissions, direct port activity of cargo handling equipment and commercial shipping vessels are modeled for representative cold and hot months in 2005. Predictions from roadway emissions are compared with the same episode modeled with CALINE4 line dispersion model. Results show high spatial variability as well as increased transport during cold months. In addition, research also shows that while the port activity significantly impacts in–port air pollution, the effects of port activity is limited to within 2–6 km of the ports. Port adjacent communities are most sensitive to roadway related emissions. AERMOD PM2.5 and NOX predictions show a peak correlation coefficient of 43% and 50% compared with observations, respectively.

Highlights

The San Pedro Bay of California houses the ports of Los Angeles and Long Beach which serve as the entry point for half of all cargo containers entering the western United States annually (American Association of Port Authorities, 2007)
The results presented are the average of using AERMOD with each of the 12 different meteorological files
This study has applied the air dispersion model AERMOD to the San Pedro bay area to examine the impact of NOX and PM2.5 emission sources originating from three sources; roadways, ships and ports

Summary

Introduction

The San Pedro Bay of California houses the ports of Los Angeles and Long Beach which serve as the entry point for half of all cargo containers entering the western United States annually (American Association of Port Authorities, 2007). Communities near the ports face potential cancer risk levels exceeding 500 in a million from severe air pollution from a wide variety of sources, including port– related activities such as ships and cargo vessels, heavily traveled freeways and surface streets with a high fraction of heavy–duty diesel trucks (Di et al, 2006; Houston et al, 2008). The area has become the focus of intensive studies through several programs of the California Air Resources Board (CARB) (Ault et al, 2009). The area surrounding the San Pedro Bay of California, shown, is the focus of this investigation The area surrounding the San Pedro Bay of California, shown in Figure 1, is the focus of this investigation

Methods

Results

Conclusion