Table 2 Spearman correlation coefficients between air pollutants and temperature in Copenhagen from 12 December 1998 to 19 December 2004 (2199 days)
PM2.5UFPNC*NO2NOxCOO3Temperature
PM100.790.370.430.400.45−0.320.25
PM2.50.400.410.390.45−0.20−0.01
UFPNC0.670.650.52−0.12−0.06
NO20.980.75−0.58−0.21
NOx0.74−0.62−0.21
CO−0.63−0.52
O30.43

  • CO, carbon monoxide; NOx, nitrogen oxide; NO2, nitrogen dioxide; O3, ozone; PM2.5, PM10, particulate matter <2.5 and <10 μm in diameter; UFPNC, ultrafine particles.

  • *Total concentration of ultrafine particles 10–700 nm in diameter (95% of total concentration comes from particles <100 nm).