A simple procedure for correcting loading effects of aethalometer data

A simple method for correcting for the loading effects of aethalometer data is presented. The formula BC(CORRECTED) = (1 + k x ATN) x BC(NONCORRECTED), where ATN is the attenuation and BC is black carbon, was used for correcting aethalometer data obtained from measurements at three different sites:...

Full description

Saved in:
Bibliographic Details
Published in:Journal of the Air & Waste Management Association (1995) 2007-10, Vol.57 (10), p.1214-1222
Main Authors: VIRKKULA, Aki, MÄKELÄ, Timo, HILLAMO, Risto, YLI-TUOMI, Tarja, HIRSIKKO, Anne, HÄMERI, Kaarle, KOPONEN, Ismo K
Format: Article
Language:English
Subjects:
Aerosols
Aerosols - analysis
Air pollution
Algorithms
Applied sciences
Atmospheric pollution
Atoms & subatomic particles
Control
Environmental aspects
Environmental Monitoring
Exact sciences and technology
Finland
Forest & brush fires
Fossil fuels
Light
Models, Chemical
Motor vehicles
Pollution
Pollution control devices
Public transportation
Seasons
Soot - analysis
Soot - chemistry
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A simple method for correcting for the loading effects of aethalometer data is presented. The formula BC(CORRECTED) = (1 + k x ATN) x BC(NONCORRECTED), where ATN is the attenuation and BC is black carbon, was used for correcting aethalometer data obtained from measurements at three different sites: a subway station in Helsinki, an urban background measurement station in Helsinki, and a rural station in Hyytiälä in central Finland. The BC data were compared with simultaneously measured aerosol volume concentrations (V). After the correction algorithm, the BC-to-V ratio remained relatively stable between consequent filter spots, which can be regarded as indirect evidence that the correction algorithm works. The k value calculated from the outdoor sites had a clear seasonal cycle that could be explained by darker aerosol in winter than in summer. When the contribution of BC to the total aerosol volume was high, the k factor was high and vice versa. In winter, the k values at all wavelengths were very close to that obtained from the subway station data. In summer, the k value was wavelength dependent and often negative. When the k value is negative, the noncorrected BC concentrations overestimated the true concentrations.
ISSN:1096-2247
2162-2906
DOI:10.3155/1047-3289.57.10.1214