http://bolin.su.se/data/cremer-2020-urban-background-1 Roxana Cremer, Paul Zieger, Johan Ström Bolin Centre Database 2020 Datafile Atmosphere Aerosols Black carbon Soot MAAP PSAP BC Absorption Absorption coefficient Urban background Anthropogenic aerosol Combustion Traffic Earth science > Atmosphere > Aerosols Roxana Cremer 2020-09-22T14:04:10+00:00 English 1 There is one datafile, in semicolon-separated (.csv) format, with data columns structured in the following way: * Date and Time in the format yyyy-mm-dd HH:MM:SS * Absorption coefficient of the instruments: PSAP1; MAAP526; MAAP637; PSAP2 All data are in the unit m⁻¹ and are 10-minute averages. The PSAP instruments are costume made by ACES luftlab, at the Department of Environmental Science, and measure at the wavelength of 526 nm. The dataset was measured on a minute based time interval and corrected according to Bond et al. (1999). The MAAP instrument measures on 637 nm, additionally it was corrected to 526 nm. Instrumentation: From Centre for Atmospheric Science, University of Manchester — [MAAP and PSAP](http://www.cas.manchester.ac.uk/restools/instruments/aerosol/maap/) and [DMPS](http://www.cas.manchester.ac.uk/restools/instruments/aerosol/differential/). The method and structure of the experiment is explained in more detail by Tunved et al. (2020). The data show a peak in the middle of the night (2018-12-17). The cause for this could not be determined in detail but one assumption is the snow cleaning machine that cleaned the roads around the buildings and the aerosol inlet during this time of the year.