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The Particle Project 2017-2018

Particle emissions across rural, urban and suburban sites in Denmark have been measured and the results gathered in a new Particle Project report by scientists from DCE – Danish Centre for Environment and Energy.

2019.03.20 | Kristian Laulund

The national study has been done for particle emissions across both rural, urban and suburban sites all over Denmark. (Photo: Colourbox)

The Particle Project 2017 presents time series of particle mass concentrations smaller than 2.5 µm (PM2.5) and particles smaller than 10 µm (PM10) at the rural site RISØ and curbside stations in Aarhus (AARHG) and Copenhagen (HCAB). Particle size distributions are furthermore analyzed at the rural site (RISØ), in urban background (HCØ), street station (HCAB) and at the suburban site (HVID).

Also presented are analysis of Elemental Carbon (EC) in particles at RISØ, HVID and HCØ, and at the latter monitoring station also benzene, which is a Volatile Organic Compound (VOC). A special issue, long time series of Primary Biomass Burning Aerosols (PBBA) mainly originating from residential wood combustion has been calculated for RISØ, HCØ and HVID from late 2009 to end of 2017.

Regional and long-range transported aerosols are expected to contribute to a large extent to the particle number in the submicrometer size range. On a relative base the highest contribution of such aerosols are found at rural background sites as e.g. RISØ in Denmark. As a consequence, long-range transported aerosols also contribute to other sites which are located with smaller distances to local sources.

For Denmark, this means that the relative contribution of such aerosols decreases when considering the suburban site at HVID, the urban background site HCØ and finally the urban curbside site HCAB. The processed aerosol at the rural, suburban and urban background sites results in a nearly monomodal particle number size distribution with mean diameters of about 40 nm and larger at RISØ, HVID and HCØ. As a general difference the particle number size distributions at HCAB appears somewhat bimodal as an additional peak was observed at around 20 nm from vehicle exhaust emissions during previous projects.

A trend of decreasing concentrations can be found at all stations when considering time periods of the order of a decade. Obviously higher particle number concentrations were observed at the suburban background station HVID compared to the urban background station HCØ. A reason might be the location of HVID surrounded within a residential area with potentially high wood stove emissions during wintertime and surrounded by a number of high-trafficked highways.

 

Read the full report here

For more information, please contact Jacob Klenø Nøjgaard

E-mail: jakn@envs.au.dk

Telephone: +45 87158553

DCE, Public / media