Figure 3
From: PM2.5 in Beijing – temporal pattern and its association with influenza
Monthly variations in PM 2.5 in Beijing for each year between 2008 and 2013. The light blue shaded area covers from the mid-November to mid-March, typically winter season in Beijing during which centralized heating is provided. Overall, the PM2.5 concentrations are higher in the winter season. During 2008, the year of the Beijing Olympics, the Chinese government imposed regulatory controls on emissions, which may be a mechanistic explanation for why concentrations in 2008 are generally lower in each month than concentrations in other years.