Fig. 2From: Acute effect of fine particulate matter and respiratory mortality in Changsha, China: a time-series analysisMonthly average PM2.5 concentration (a) and temperature bar graph (b) in Changsha city from January 1, 2015 to December 31, 2018. The horizontal red dotted line shows annual average concentration of PM2.5 (a) and temperature (b)Back to article page