Table 4

Principal components analysis for pollutants and meteorological variables for the years 2003–2009, the significant factor loadings and the components according to the amount of variance explained

Component 1Component 2Component 3Component 4Component 5Component 6Component 7Component 8
NO2−0.1490.6980.648−0.1480.202
O3−0.7040.6910.146
PM10−0.979−0.159
H2S0.9340.348
SO20.2300.970
Temperature−0.268−0.3190.900
Relative humidity−0.992
PM10/NO2*−0.9680.231
  • *Ratio between PM10 and NO2.

  • H2S, hydrogen sulfide; NO2, nitrogen dioxide; O3, ozone; PM10, particulate matter ≤10 µm in aerodynamic diameter; SO2, sulfur dioxide.