Research Article

Meteorological Influences on Seasonal Variation of Fine Particulate Matter in Cities over Southern Ontario, Canada

Figure 2

Daily variation of PM2.5 at 12 cities in Ontario in 2006, with three 24-hour guidelines: 25  g/m3 by the World Health Organization (WHO) guideline, 30  g/m3 by the Canadian Wide Standards (CWS), and 35  g/m3 by the Environmental Protection Agency (EPA) of USA guideline. The -axis indicates months of the year by their initial letters. The cities are ordered by descending latitude (see Table 1 and Figure 1(a)).
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