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Multi-Year Measurements of Black Carbon Aerosols and Solar Radiation over Himadri, Ny-Ålesund
Published in Neloy Khare, Climate Change in the Arctic, 2022
S. M. Sonbawne, G. Meena, S. K. Saha, G. Pandithurai, P. D. Safai, P. C. S. Devara
Aethalometer is a widely used instrument for continuous observation of ambient BC mass concentration in the diverse environment over the globe with a typical uncertainty of <5% (Babu et al., 2011). Two sets of seven-channel Aethalometer (Model AE-42 and AE-30, M/s Magee Scientific Co., USA) were continuously operated during the observations. The Aethalometer AE-42 was used at the Himadri station inside the Ny-Ålesund town. The other Aethalometer AE-30 was employed at Gruvebadet observatory (78.9°N, 11.9°E), situated 1.2 km away at the southern side of the city foothill of Zeppelin Mountain. The AE-42 observations represent more local anthropogenic activity, whereas the AE-30 is away from the local anthropogenic activity. . AE-42 and AE-30 were operated at sample airflow rate of 3 and 5 LPM with time interval of 5 and 30 minutes, respectively. Both Aethalometers were operated at 3 m height above ground. These differences in measuring time interval were put purposely as the AE-42 was operated in town where the local activity is more, as it was restricted to the AE-30 observational site.
Particulate matter
Published in Abhishek Tiwary, Ian Williams, Air Pollution, 2018
Aethalometer: The aethalometer is used to measure real-time total concentrations of black carbon (BC) particles. The particles are sampled at around 10 L min−1 onto a quartz fibre filter, through which a broad-spectrum light source is shone. The beam is attenuated, and the attenuation converted into a mass concentration of BC on the filter via a calibration factor (expressed in m2 g−1). The calibration factor itself varies from site to site, as it will depend on the detailed properties of the BC particles; different workers have found values ranging from 20 in urban areas down to five in remote regions. These values compare with a figure of around 0.05 for mineral dusts such as Saharan sand or road quartz. There is a problem with converting the measurements directly into the equivalent scattering of those particles in the atmosphere, because the close packing of the particles on the filter results in multiple scattering. The same principle has been used in the US to measure coefficient of haze (COH).
Measurement of gases and particles
Published in Abhishek Tiwary, Jeremy Colls, Air Pollution, 2017
The aethalometer is used to measure real-time total concentrations of black carbon (BC) particles. The particles are sampled at around 10 l min–1 onto a quartz fibre filter, through which a broad-spectrum light source is shone. The beam is attenuated, and the attenuation converted into a mass concentration of BC on the filter via a calibration factor (expressed in m2 g–1). The calibration factor itself varies from site to site, since it will depend on the detailed properties of the BC particles; different workers have found values ranging from 20 in urban areas down to five in remote regions. These values compare with a figure of around 0.05 for mineral dusts such as Saharan sand or road quartz. There is a problem with converting the measurements directly into the equivalent scattering of those particles in the atmosphere, because the close packing of the particles on the filter results in multiple scattering. The same principle has been used in the US to measure coefficient of haze (COH).
Development of drone-based filter sampling system for carbonaceous aerosol analysis using thermal–optical transmittance method
Published in Aerosol Science and Technology, 2023
Jaebeom Park, Dong-Bin Kwak, Minwoo Baek, Songhui Lee, Woo Young Kim, Ki Ae Kim, Ji Yi Lee, Kang-Ho Ahn, Handol Lee
In the comparative experiment conducted on 20 October, we simultaneously operated an OPC (11-D, GRIMM) and Aethalometer (AE51, AethLabs), and both instruments were used only for ground-level measurements. The OPC measures the number concentrations of PM for particle size ranging from 0.253 to 35.15 µm by detecting light scattered from particles passing through a diode laser with a wavelength of 655 nm. Moreover, the OPC provides the PM mass concentrations, i.e., PM1, PM2.5, and PM10, calculated from the measured number concentrations. The AE51 Aethalometer measures the BC concentrations from the attenuation of light (wavelength of 880 nm) based on the continuous acquisition of particle deposits on a filter. The sample flow rate of the Aethalometer was set to 0.1 L min−1. PM and BC concentration data were recorded every 6 and 30 s, respectively.
Realistic operation of two residential cordwood-fired outdoor hydronic heater appliances—Part 3: Optical properties of black and brown carbon emissions
Published in Journal of the Air & Waste Management Association, 2022
Jake Lindberg, Marilyn Wurth, Brian P. Frank, Shida Tang, Gil LaDuke, Rebecca Trojanowski, Thomas Butcher, Devinder Mahajan
Aethalometer data can also be used to estimate the fraction of BC in an aerosol. In most laboratory combustion emission studies the quantification of BC and BrC is performed on the basis of elemental and organic carbon (EC and OC), which is measured using a thermo-optical method (Karanasiou et al. 2015; WHO Regional Office for Europe 2012). However, this method requires collection of an integrated sample and as a result, the measurements cannot be parsed sufficiently to measure transient combustion conditions in many cases (Karanasiou et al. 2015). Recently, an aethalometer based method for near real-time EC and OC analysis has been proposed (Rigler et al. 2020). This method makes use of an aethalometer and a separate instrument to measure PM concentration. By comparing the two results, it is possible to derive an estimate of the BC fraction of the aerosol.PM emitted from biomass combustion appliances can vary due to factors such as appliance design, fuel type, size, and composition, and appliance operating conditions such as temperature, excess air, heat output condition, and burn rate (Johansson et al. 2004; Lillieblad et al. 2004; Obernberger, Brunner, and Barnthaler 2007; Md. Obaidullah, Verma, and De Ruyck 2012; Kinsey et al. 2012, Shen, Influence of fuel mass load, oxygen supply and burning rate on emission factor and size distribution of carbonaceous particulate matter from indoor corn straw burning 2013; Schmidl 2011; Vicente et al. 2015; Kortelainen et al. 2018) and it follows that the optical properties and BC emission from biomass combustion devices will also vary with these factors (Martinsson et al. 2015).
Evaluation of black carbon mass concentrations using a miniaturized aethalometer: Intercomparison with a continuous soot monitoring system (COSMOS) and a single-particle soot photometer (SP2)
Published in Aerosol Science and Technology, 2020
Takuma Miyakawa, Petr Mordovskoi, Yugo Kanaya
Some low-cost and/or light-weight instruments have been developed for measuring BC (Caubel, Cados, and Kirchstetter 2018; Cheng and Lin 2013). For example, a miniaturized, palm-sized aethalometer (MicroAeth AE51, Aethlabs, US), which is a type of filter-photometer, was recently developed and successfully deployed. This equipment has applications in surveying the fine-scale spatial distribution of BC through multi-point or mobile observations in the vicinity of emission sources, and in investigating BC vertical profiles using unmanned aerial vehicles (UAVs) and balloons (Ferrero et al. 2011, 2014, 2016). Viana et al. (2015) evaluated the instrumental errors of the AE51 based on six-unit simultaneous operations with a stationary instrument. Cheng and Lin (2013) evaluated the particle loading effect on the performance of the AE51 using a different aethalometer, possibly affected by light-scattering particles for a limited length of the time. These evaluations remain limited, however, especially with respect to light-scattering particles.