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This study analyzes the relevance of different parameters and compares PM10, PM2.5, PM1, and particle number concentrations in Switzerland. It provides health-related information and examines the source-related information of different particle fractions.
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Parallel measurements of PM10, PM2.5, PM1 and particle number concentrations in Switzerland Robert Gehrig Empa, Air Pollution/Environmental Technologies CH-8600 Dübendorf
Content • Relevance of different parameters • Comparison PM10, PM2.5, PM1 • Particle number concentrations
PM10 and PM2.5 • Health related information • Thoracic fraction (PM10) • Alveolar fraction (PM2.5) • Coarse fraction (PM10-2.5)
Typical urban aerosol (EPA 1982) 0.1 1 10 diameter (mm)
PM10 and PM1 • Source related information • Combustion particles and secondary aerosols (PM1) • Crustal and mechanically produced particles (PM10-PM1)
Chaumont Bern Payerne Zürich
PM10 PM2.5 PM1 PM: annual means 1998 - 2005
Seasonal trends of PM10 and PM2.5 Monthly means 1998-2005 PM10 PM2.5
Seasonal trends of PM10 and PM1 Monthly means 1998-2005 PM10 PM1 (2003-2005)
Average daily ratios PM2.5/PM10 PM1/PM10 Basel (suburban) 0.760.60 Lugano (urban) 0.740.59 Zürich (urban) 0.75 Payerne (rural) 0.75 Chaumont (rural, 1100 m asl) 0.750.63 Härkingen (motorway) 0.59 Bern (street canyon) 0.61 0.49
Correlation r2 of the parallel PM10- and PM2.5- measurements (daily values 1998-2005) Basel (suburban) 0.94 Lugano (urban) 0.94 Zürich (urban)*) 0.95 Payerne (rural) 0.94 Bern (street canyon) 0.86 Chaumont (rural, 1100 m asl) 0.85 *) 1998-2002 only
Jura 700-1000 m Zürich 400 m Basel 250 m 70 km PM und meteorology (daily values)
Alpen 2500-3500 m Zürich 400 m Lugano 200 m 150 km PM und meteorology (daily values)
Chaumont 1100 m Payerne 500 m 20 km PM und meteorology (daily values)
Particle numbers • Dominated by fresh combustion particles (Ultrafine particles < 100 nm) • Not covered by particle mass measurements (Mass of one 10µm-particle = 109 10nm particles) • Specific health effects possible
Residence time of particles in the atmosphere (Jaenicke 1982) Residence time of the aerosol near ground 1 week scavenging 1 day 1 hour residence time (s) n diffusion/coagulation sedimentation 1 minute 1 second aerodynamic diameter (µm)
Härkingen (motorway)Influence of wind direction N PM1 NO PM10 NO2 particle numbers (part/cm3) PM10 and PM1 (µg/m3) nitrogen oxides (ppm)
Conclusions • PM2.5: Health related sampling (long term effects) • PM10-PM2.5: Health related sampling (short term effects) • PM1: Combustion aerosols, secondary aerosols • PM10-PM1: Crustal and mechanically produced particles • Particle numbers: Ultrafine particles • PM measurements • often highly correlated and homogeneously distributed over large areas • Particle number concentrations • low correlation with PM, high spacial variability
Weekly cycle of particle number concentrations Partikelanzahl Verkehr