Chemistry Reference
In-Depth Information
a
Urban
background
(regional)
5.7%
Urban
background
(cooking)
6.6%
Urban
background (solid
fuel/nitrate)
2.0%
Urban
background (sub
urban traffic)
7.6%
Exhaust (solid
mode)
38.0%
Urban
background
(accumulation
mode)
6.3%
Resuspension
4.8%
Brake dust
1.7%
Exhaust
(nucleation mode)
27.4%
Unaccounted
3%
b
Regional/urban
background
24%
Photochemically
induced
nucleation
3%
Sea spray
2%
Industrial source
2%
Vehicle exhaust
65%
Mineral dust
1%
Fig. 2 Typical contribution of various sources towards (a) roadside PNCs in the 14.9-10,000 nm
size range London, and (b) urban background PNCs in the 13-800 nm size range in Barcelona.
Roadside and urban background data has been taken from Harrison et al. [
19
] and Pey et al. [
18
],
respectively
different years, meteorological conditions, traffic density, minimum and maximum
cut-off size by instruments used for measurements, sampling duration, averaging
time of samples, year of study, and the type and length of sampling tubes used and
