Impact of cruise ship emissions in Victoria, BC, Canada

Characterization of the effects of cruise ship emissions on local air quality is scarce. Our objective was to investigate community level concentrations of fine particulate matter (PM2.5), nitrogen dioxide (NO2) and sulphur dioxide (SO2) associated with cruise ships in James Bay, Victoria, British Columbia (BC), Canada. Data obtained over four years (2005–2008) at the nearest air quality network site located 3.5 km from the study area, a CALPUFF modeling exercise (2007), and continuous measurements taken in the James Bay community over a three-month period during the 2009 cruise ship season were examined. Concentrations of PM2.5 and nitrogen oxide (NO) were elevated on weekends with ships present with winds from the direction of the terminal to the monitoring station. SO2 displayed the greatest impact from the presence of cruise ships in the area. Network data showed peaks in hourly SO2 when ships were in port during all years. The CALPUFF modeling analysis found predicted 24-hour SO2 levels to exceed World Health Organization (WHO) guidelines of 20 μg m−3 for approximately 3% of 24-hour periods, with a maximum 24-hour concentration in the community of 41 μg m−3; however, the CALPUFF model underestimated concentrations when predicted and measured concentrations were compared at the network site. Continuous monitoring at the location in the community predicted to experience highest SO2 concentrations measured a maximum 24-hour concentration of 122 μg m−3 and 16% of 24-hour periods were above the WHO standard. The 10-minute concentrations of SO2 reached up to 599 μg m−3 and exceeded the WHO 10-minute SO2 guideline (500 μg m−3) for 0.03% of 10-minute periods. No exceedences of BC Provincial or Canadian guidelines or standards were observed.