Characteristics and source apportionment of black carbon in the Helsinki metropolitan area, Finland

Aku Helin; Jarkko V. Niemi; Aki Virkkula; Liisa Pirjola; Kimmo Teinilä; John Backman; Minna Aurela; Sanna Saarikoski; Topi Rönkkö; Eija Asmi; Hilkka Timonen

doi:10.1016/j.atmosenv.2018.07.022

Characteristics and source apportionment of black carbon in the Helsinki metropolitan area, Finland

Aku Helin, Jarkko V. Niemi, Aki Virkkula, Liisa Pirjola, Kimmo Teinilä, John Backman, Minna Aurela, Sanna Saarikoski, Topi Rönkkö, Eija Asmi, Hilkka Timonen

Research output: Contribution to journal › Article › Scientific › peer-review

143 Citations (Scopus)

130 Downloads (Pure)

Abstract

Black carbon is emitted from the incomplete combustion of carbonaceous fuels and will detrimentally affect air quality, climate and human health. In this study, equivalent black carbon (eBC) concentrations were measured by using an aethalometer (AE33) at three different locations in the Helsinki metropolitan area, Finland from October 2015 to May 2017. One sampling site was located in an urban street canyon (SC, sampling period 18 months) and two of the sampling sites were located in suburban detached house (DH) areas (DH1, 13 months and DH2, 5 months). Based on the campaign averages, the eBC concentration levels were higher at the street canyon site (1690 ± 1520 ng/m³) than at the residential detached house areas (DH1 = 880 ± 1500 ng/m³ and DH2 = 1040 ± 2130 ng/m³). The contribution of eBC from fossil fuel (BC_FF) and wood burning (BC_WB) were estimated based on the spectral dependence of light absorption of different sources. The spectral behavior is described using absorption Ångström exponent (α) values for both fossil fuel (α_FF) and wood burning (α_WB) that were determined using concurrent wood burning tracer (levoglucosan) measurements. Based on the source apportionment, the contribution of BC_WB to eBC was clearly higher at the detached house area sites DH1 (41 ± 14%) and DH2 (46 ± 15%) than at the urban street canyon site (15 ± 14%). A distinct seasonal dependency was observed in the eBC concentration levels at the detached house areas. The highest concentrations were detected during the cold seasons due to residential wood combustion. On the opposite, at the SC site, the concentration levels of eBC were rather constant throughout the campaign, being dominated by the BC_FF emissions from close-by vehicular traffic. Substantial temporal and spatial variability in eBC concentrations and sources were observed within the Helsinki metropolitan area. eBC is shown to be closely tied to the characteristics of the measurement site, season, meteorological conditions and the time of the day.

Original language	English
Pages (from-to)	87-98
Number of pages	12
Journal	Atmospheric Environment
Volume	190
DOIs	https://doi.org/10.1016/j.atmosenv.2018.07.022
Publication status	Published - 1 Oct 2018
Publication type	A1 Journal article-refereed

Keywords

Absorption Ångström exponent
Aethalometer
Biomass burning
Black carbon
Fossil fuel

Publication forum classification

Publication forum level 1

ASJC Scopus subject areas

General Environmental Science
Atmospheric Science

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

Access to Document

10.1016/j.atmosenv.2018.07.022Licence: CC BY-NC-ND

1-s2.0-S1352231018304692-main
Under a Creative Commons license http://creativecommons.org/licenses/by-nc-nd/4.0/
Final published version, 1.92 MBLicence: CC BY-NC-ND

http://urn.fi/URN:NBN:fi:tty-201809032251Licence: CC BY-NC-ND

Cite this

@article{60e600c74b954305b886537cf365a8b3,

title = "Characteristics and source apportionment of black carbon in the Helsinki metropolitan area, Finland",

abstract = "Black carbon is emitted from the incomplete combustion of carbonaceous fuels and will detrimentally affect air quality, climate and human health. In this study, equivalent black carbon (eBC) concentrations were measured by using an aethalometer (AE33) at three different locations in the Helsinki metropolitan area, Finland from October 2015 to May 2017. One sampling site was located in an urban street canyon (SC, sampling period 18 months) and two of the sampling sites were located in suburban detached house (DH) areas (DH1, 13 months and DH2, 5 months). Based on the campaign averages, the eBC concentration levels were higher at the street canyon site (1690 ± 1520 ng/m3) than at the residential detached house areas (DH1 = 880 ± 1500 ng/m3 and DH2 = 1040 ± 2130 ng/m3). The contribution of eBC from fossil fuel (BCFF) and wood burning (BCWB) were estimated based on the spectral dependence of light absorption of different sources. The spectral behavior is described using absorption {\AA}ngstr{\"o}m exponent (α) values for both fossil fuel (αFF) and wood burning (αWB) that were determined using concurrent wood burning tracer (levoglucosan) measurements. Based on the source apportionment, the contribution of BCWB to eBC was clearly higher at the detached house area sites DH1 (41 ± 14%) and DH2 (46 ± 15%) than at the urban street canyon site (15 ± 14%). A distinct seasonal dependency was observed in the eBC concentration levels at the detached house areas. The highest concentrations were detected during the cold seasons due to residential wood combustion. On the opposite, at the SC site, the concentration levels of eBC were rather constant throughout the campaign, being dominated by the BCFF emissions from close-by vehicular traffic. Substantial temporal and spatial variability in eBC concentrations and sources were observed within the Helsinki metropolitan area. eBC is shown to be closely tied to the characteristics of the measurement site, season, meteorological conditions and the time of the day.",

keywords = "Absorption {\AA}ngstr{\"o}m exponent, Aethalometer, Biomass burning, Black carbon, Fossil fuel",

author = "Aku Helin and Niemi, {Jarkko V.} and Aki Virkkula and Liisa Pirjola and Kimmo Teinil{\"a} and John Backman and Minna Aurela and Sanna Saarikoski and Topi R{\"o}nkk{\"o} and Eija Asmi and Hilkka Timonen",

year = "2018",

month = oct,

day = "1",

doi = "10.1016/j.atmosenv.2018.07.022",

language = "English",

volume = "190",

pages = "87--98",

journal = "Atmospheric Environment",

issn = "1352-2310",

publisher = "Elsevier Ltd.",

}

TY - JOUR

T1 - Characteristics and source apportionment of black carbon in the Helsinki metropolitan area, Finland

AU - Helin, Aku

AU - Niemi, Jarkko V.

AU - Virkkula, Aki

AU - Pirjola, Liisa

AU - Teinilä, Kimmo

AU - Backman, John

AU - Aurela, Minna

AU - Saarikoski, Sanna

AU - Rönkkö, Topi

AU - Asmi, Eija

AU - Timonen, Hilkka

PY - 2018/10/1

Y1 - 2018/10/1

N2 - Black carbon is emitted from the incomplete combustion of carbonaceous fuels and will detrimentally affect air quality, climate and human health. In this study, equivalent black carbon (eBC) concentrations were measured by using an aethalometer (AE33) at three different locations in the Helsinki metropolitan area, Finland from October 2015 to May 2017. One sampling site was located in an urban street canyon (SC, sampling period 18 months) and two of the sampling sites were located in suburban detached house (DH) areas (DH1, 13 months and DH2, 5 months). Based on the campaign averages, the eBC concentration levels were higher at the street canyon site (1690 ± 1520 ng/m3) than at the residential detached house areas (DH1 = 880 ± 1500 ng/m3 and DH2 = 1040 ± 2130 ng/m3). The contribution of eBC from fossil fuel (BCFF) and wood burning (BCWB) were estimated based on the spectral dependence of light absorption of different sources. The spectral behavior is described using absorption Ångström exponent (α) values for both fossil fuel (αFF) and wood burning (αWB) that were determined using concurrent wood burning tracer (levoglucosan) measurements. Based on the source apportionment, the contribution of BCWB to eBC was clearly higher at the detached house area sites DH1 (41 ± 14%) and DH2 (46 ± 15%) than at the urban street canyon site (15 ± 14%). A distinct seasonal dependency was observed in the eBC concentration levels at the detached house areas. The highest concentrations were detected during the cold seasons due to residential wood combustion. On the opposite, at the SC site, the concentration levels of eBC were rather constant throughout the campaign, being dominated by the BCFF emissions from close-by vehicular traffic. Substantial temporal and spatial variability in eBC concentrations and sources were observed within the Helsinki metropolitan area. eBC is shown to be closely tied to the characteristics of the measurement site, season, meteorological conditions and the time of the day.

AB - Black carbon is emitted from the incomplete combustion of carbonaceous fuels and will detrimentally affect air quality, climate and human health. In this study, equivalent black carbon (eBC) concentrations were measured by using an aethalometer (AE33) at three different locations in the Helsinki metropolitan area, Finland from October 2015 to May 2017. One sampling site was located in an urban street canyon (SC, sampling period 18 months) and two of the sampling sites were located in suburban detached house (DH) areas (DH1, 13 months and DH2, 5 months). Based on the campaign averages, the eBC concentration levels were higher at the street canyon site (1690 ± 1520 ng/m3) than at the residential detached house areas (DH1 = 880 ± 1500 ng/m3 and DH2 = 1040 ± 2130 ng/m3). The contribution of eBC from fossil fuel (BCFF) and wood burning (BCWB) were estimated based on the spectral dependence of light absorption of different sources. The spectral behavior is described using absorption Ångström exponent (α) values for both fossil fuel (αFF) and wood burning (αWB) that were determined using concurrent wood burning tracer (levoglucosan) measurements. Based on the source apportionment, the contribution of BCWB to eBC was clearly higher at the detached house area sites DH1 (41 ± 14%) and DH2 (46 ± 15%) than at the urban street canyon site (15 ± 14%). A distinct seasonal dependency was observed in the eBC concentration levels at the detached house areas. The highest concentrations were detected during the cold seasons due to residential wood combustion. On the opposite, at the SC site, the concentration levels of eBC were rather constant throughout the campaign, being dominated by the BCFF emissions from close-by vehicular traffic. Substantial temporal and spatial variability in eBC concentrations and sources were observed within the Helsinki metropolitan area. eBC is shown to be closely tied to the characteristics of the measurement site, season, meteorological conditions and the time of the day.

KW - Absorption Ångström exponent

KW - Aethalometer

KW - Biomass burning

KW - Black carbon

KW - Fossil fuel

U2 - 10.1016/j.atmosenv.2018.07.022

DO - 10.1016/j.atmosenv.2018.07.022

M3 - Article

AN - SCOPUS:85051269403

SN - 1352-2310

VL - 190

SP - 87

EP - 98

JO - Atmospheric Environment

JF - Atmospheric Environment

ER -

Characteristics and source apportionment of black carbon in the Helsinki metropolitan area, Finland

Abstract

Keywords

Publication forum classification

ASJC Scopus subject areas

UN SDGs

Access to Document

Fingerprint

Cite this