On Aethalometer measurement uncertainties and an instrument correction factor for the Arctic
Several types of filter-based instruments are used to estimate aerosol light absorption coefficients. Two significant results are presented based on Aethalometer measurements at six Arctic stations from 2012 to 2014. First, an alternative method of post-processing the Aethalometer data is presented,...
Published in: | Atmospheric Measurement Techniques |
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ftcopernicus:oai:publications.copernicus.org:amt54698 2023-05-15T14:47:07+02:00 On Aethalometer measurement uncertainties and an instrument correction factor for the Arctic Backman, John Schmeisser, Lauren Virkkula, Aki Ogren, John A. Asmi, Eija Starkweather, Sandra Sharma, Sangeeta Eleftheriadis, Konstantinos Uttal, Taneil Jefferson, Anne Bergin, Michael Makshtas, Alexander Tunved, Peter Fiebig, Markus 2018-02-01 application/pdf https://doi.org/10.5194/amt-10-5039-2017 https://amt.copernicus.org/articles/10/5039/2017/ eng eng doi:10.5194/amt-10-5039-2017 https://amt.copernicus.org/articles/10/5039/2017/ eISSN: 1867-8548 Text 2018 ftcopernicus https://doi.org/10.5194/amt-10-5039-2017 2020-07-20T16:23:29Z Several types of filter-based instruments are used to estimate aerosol light absorption coefficients. Two significant results are presented based on Aethalometer measurements at six Arctic stations from 2012 to 2014. First, an alternative method of post-processing the Aethalometer data is presented, which reduces measurement noise and lowers the detection limit of the instrument more effectively than boxcar averaging. The biggest benefit of this approach can be achieved if instrument drift is minimised. Moreover, by using an attenuation threshold criterion for data post-processing, the relative uncertainty from the electronic noise of the instrument is kept constant. This approach results in a time series with a variable collection time (Δ t ) but with a constant relative uncertainty with regard to electronic noise in the instrument. An additional advantage of this method is that the detection limit of the instrument will be lowered at small aerosol concentrations at the expense of temporal resolution, whereas there is little to no loss in temporal resolution at high aerosol concentrations ( > 2.1–6.7 Mm −1 as measured by the Aethalometers). At high aerosol concentrations, minimising the detection limit of the instrument is less critical. Additionally, utilising co-located filter-based absorption photometers, a correction factor is presented for the Arctic that can be used in Aethalometer corrections available in literature. The correction factor of 3.45 was calculated for low-elevation Arctic stations. This correction factor harmonises Aethalometer attenuation coefficients with light absorption coefficients as measured by the co-located light absorption photometers. Using one correction factor for Arctic Aethalometers has the advantage that measurements between stations become more inter-comparable. Text Arctic Copernicus Publications: E-Journals Arctic Atmospheric Measurement Techniques 10 12 5039 5062 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
Several types of filter-based instruments are used to estimate aerosol light absorption coefficients. Two significant results are presented based on Aethalometer measurements at six Arctic stations from 2012 to 2014. First, an alternative method of post-processing the Aethalometer data is presented, which reduces measurement noise and lowers the detection limit of the instrument more effectively than boxcar averaging. The biggest benefit of this approach can be achieved if instrument drift is minimised. Moreover, by using an attenuation threshold criterion for data post-processing, the relative uncertainty from the electronic noise of the instrument is kept constant. This approach results in a time series with a variable collection time (Δ t ) but with a constant relative uncertainty with regard to electronic noise in the instrument. An additional advantage of this method is that the detection limit of the instrument will be lowered at small aerosol concentrations at the expense of temporal resolution, whereas there is little to no loss in temporal resolution at high aerosol concentrations ( > 2.1–6.7 Mm −1 as measured by the Aethalometers). At high aerosol concentrations, minimising the detection limit of the instrument is less critical. Additionally, utilising co-located filter-based absorption photometers, a correction factor is presented for the Arctic that can be used in Aethalometer corrections available in literature. The correction factor of 3.45 was calculated for low-elevation Arctic stations. This correction factor harmonises Aethalometer attenuation coefficients with light absorption coefficients as measured by the co-located light absorption photometers. Using one correction factor for Arctic Aethalometers has the advantage that measurements between stations become more inter-comparable. |
format |
Text |
author |
Backman, John Schmeisser, Lauren Virkkula, Aki Ogren, John A. Asmi, Eija Starkweather, Sandra Sharma, Sangeeta Eleftheriadis, Konstantinos Uttal, Taneil Jefferson, Anne Bergin, Michael Makshtas, Alexander Tunved, Peter Fiebig, Markus |
spellingShingle |
Backman, John Schmeisser, Lauren Virkkula, Aki Ogren, John A. Asmi, Eija Starkweather, Sandra Sharma, Sangeeta Eleftheriadis, Konstantinos Uttal, Taneil Jefferson, Anne Bergin, Michael Makshtas, Alexander Tunved, Peter Fiebig, Markus On Aethalometer measurement uncertainties and an instrument correction factor for the Arctic |
author_facet |
Backman, John Schmeisser, Lauren Virkkula, Aki Ogren, John A. Asmi, Eija Starkweather, Sandra Sharma, Sangeeta Eleftheriadis, Konstantinos Uttal, Taneil Jefferson, Anne Bergin, Michael Makshtas, Alexander Tunved, Peter Fiebig, Markus |
author_sort |
Backman, John |
title |
On Aethalometer measurement uncertainties and an instrument correction factor for the Arctic |
title_short |
On Aethalometer measurement uncertainties and an instrument correction factor for the Arctic |
title_full |
On Aethalometer measurement uncertainties and an instrument correction factor for the Arctic |
title_fullStr |
On Aethalometer measurement uncertainties and an instrument correction factor for the Arctic |
title_full_unstemmed |
On Aethalometer measurement uncertainties and an instrument correction factor for the Arctic |
title_sort |
on aethalometer measurement uncertainties and an instrument correction factor for the arctic |
publishDate |
2018 |
url |
https://doi.org/10.5194/amt-10-5039-2017 https://amt.copernicus.org/articles/10/5039/2017/ |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
eISSN: 1867-8548 |
op_relation |
doi:10.5194/amt-10-5039-2017 https://amt.copernicus.org/articles/10/5039/2017/ |
op_doi |
https://doi.org/10.5194/amt-10-5039-2017 |
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Atmospheric Measurement Techniques |
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10 |
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12 |
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5039 |
op_container_end_page |
5062 |
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1766318262249848832 |