Table 2: The locations of the six points where meteorological data was collected.
ble 2, as well as shown on the map in Figure 1. Each station provided data
for every meteorological variable.
Temperature was measured in degrees Celsius. Air temperature can affect the efficiency of engines; Ni et al. [33] found that vehicles starting while
intaking colder air have increased CO and VOC emissions. Temperature is
also strongly influenced by the radiative flux, which also affects the rate of
photochemically produced pollutants like 03, and in the absence of direct radiative flux measurements temperature might represent that variable to some
extent. Tai et al. [46] found a generally strong correlation between temperature and PM 2 .5 , and Dawson et al. [18] extended that to a causal relationship.
Aw and Kleeman [3] also found a positive correlation between temperature
and 03 [19]. A map showing the temperature distribution for noon on April
1, which exhibits a representative spatial distribution of temperatures, can
be seen in Figure 2.