22 results on '"Servomaa, Henri"'
Search Results
2. The Four-Wavelength Photoacoustic Aerosol Absorption Spectrometer PAAS-4λ
- Author
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Schnaiter, Martin, primary, Linke, Claudia, additional, Asmi, Eija, additional, Servomaa, Henri, additional, Hyvärinen, Antti-Pekka, additional, Ohata, Sho, additional, Kondo, Yutaka, additional, and Järvinen, Emma, additional
- Published
- 2023
- Full Text
- View/download PDF
3. Ice nucleating particle measurement at Helsinki
- Author
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Perez Fogwill, Germán, primary, Welti, André, additional, Servomaa, Henri, additional, Timo, Anttila, additional, Piedehierro, Ana, additional, Leskinen, Ari, additional, Komppula, Mika, additional, Hyvärinen, Antti, additional, and Asmi, Eija, additional
- Published
- 2023
- Full Text
- View/download PDF
4. Supplementary material to "The Four-Wavelength Photoacoustic Aerosol Absorption Spectrometer PAAS-4λ"
- Author
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Schnaiter, Franz Martin, primary, Linke, Claudia, additional, Asmi, Eija, additional, Servomaa, Henri, additional, Hyvärinen, Antti-Pekka, additional, Ohata, Sho, additional, Kondo, Yutaka, additional, and Järvinen, Emma, additional
- Published
- 2023
- Full Text
- View/download PDF
5. The Four-Wavelength Photoacoustic Aerosol Absorption Spectrometer PAAS-4λ
- Author
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Schnaiter, Franz Martin, primary, Linke, Claudia, additional, Asmi, Eija, additional, Servomaa, Henri, additional, Hyvärinen, Antti-Pekka, additional, Ohata, Sho, additional, Kondo, Yutaka, additional, and Järvinen, Emma, additional
- Published
- 2023
- Full Text
- View/download PDF
6. The four-wavelength Photoacoustic Aerosol Absorption Spectrometer (PAAS-4λ).
- Author
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Schnaiter, Franz Martin, Linke, Claudia, Asmi, Eija, Servomaa, Henri, Hyvärinen, Antti-Pekka, Ohata, Sho, Kondo, Yutaka, and Järvinen, Emma
- Subjects
AIR quality monitoring stations ,AEROSOLS ,ACOUSTIC resonators ,SPECTROMETERS ,AIR quality - Abstract
In this paper, the Photoacoustic Aerosol Absorption Spectrometer (PAAS-4 λ) is introduced. PAAS-4 λ was specifically developed for long-term monitoring tasks in (unattended) air quality stations. It uses four wavelengths coupled to a single acoustic resonator in a compact and robust set-up. The instrument has been thoroughly characterized and carefully calibrated in the laboratory using NO 2 /air mixtures and Nigrosin aerosol. It has an ultimate 1σ detection limit below 0.1 Mm -1 , at a measurement precision and accuracy of 3 % and 10 %, respectively. In order to demonstrate the PAAS-4 λ suitability for long-term monitoring tasks, the instrument is currently validated at the air quality monitoring station Pallas in Finland, about 140 km north of the Arctic circle. A total of 11 months of PAAS-4 λ data from this deployment are presented and discussed in terms of instrument performance. Intercomparisons with the filter-based photometers of a continuous soot monitoring system (COSMOS), the Multi-Angle Absorption Photometer (MAAP), and Aethalometer (AE33) demonstrate the capabilities and value of PAAS-4 λ , as well as for the validation of the widely used filter-based instruments. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
7. Estimates of mass absorption cross sections of black carbon for filter-based absorption photometers in the Arctic
- Author
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Ohata, Sho, primary, Mori, Tatsuhiro, additional, Kondo, Yutaka, additional, Sharma, Sangeeta, additional, Hyvärinen, Antti, additional, Andrews, Elisabeth, additional, Tunved, Peter, additional, Asmi, Eija, additional, Backman, John, additional, Servomaa, Henri, additional, Veber, Daniel, additional, Eleftheriadis, Konstantinos, additional, Vratolis, Stergios, additional, Krejci, Radovan, additional, Zieger, Paul, additional, Koike, Makoto, additional, Kanaya, Yugo, additional, Yoshida, Atsushi, additional, Moteki, Nobuhiro, additional, Zhao, Yongjing, additional, Tobo, Yutaka, additional, Matsushita, Junji, additional, and Oshima, Naga, additional
- Published
- 2021
- Full Text
- View/download PDF
8. Absorption instruments inter-comparison campaign at the Arctic Pallas station
- Author
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Asmi, Eija, primary, Backman, John, additional, Servomaa, Henri, additional, Virkkula, Aki, additional, Gini, Maria I., additional, Eleftheriadis, Konstantinos, additional, Müller, Thomas, additional, Ohata, Sho, additional, Kondo, Yutaka, additional, and Hyvärinen, Antti, additional
- Published
- 2021
- Full Text
- View/download PDF
9. Supplementary material to "Estimates of mass absorption cross sections of black carbon for filter-based absorption photometers in the Arctic"
- Author
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Ohata, Sho, primary, Mori, Tatsuhiro, additional, Kondo, Yutaka, additional, Sharma, Sangeeta, additional, Hyvärinen, Antti, additional, Andrews, Elisabeth, additional, Tunved, Peter, additional, Asmi, Eija, additional, Backman, John, additional, Servomaa, Henri, additional, Veber, Daniel, additional, Eleftheriadis, Konstantinos, additional, Vratolis, Stergios, additional, Koike, Makoto, additional, Kanaya, Yugo, additional, Yoshida, Atsushi, additional, Moteki, Nobuhiro, additional, Zhao, Yongjing, additional, Tobo, Yutaka, additional, Matsushita, Junji, additional, and Oshima, Naga, additional
- Published
- 2021
- Full Text
- View/download PDF
10. Estimates of mass absorption cross sections of black carbon for filter-based absorption photometers in the Arctic
- Author
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Ohata, Sho, Mori, Tatsuhiro, Kondo, Yutaka, Sharma, Sangeeta, Hyvärinen, Antti, Andrews, Elisabeth, Tunved, Peter, Asmi, Eija, Backman, John, Servomaa, Henri, Veber, Daniel, Koike, Makoto, Kanaya, Yugo, Yoshida, Atsushi, Moteki, Nobuhiro, Zhao, Yongjing, Matsushita, Junji, Oshima, Naga, Eleftheriadis, Konstantinos, Vratolis, Stergios, Krejci, Radovan, Zieger, Paul, Tobo, Yutaka, Ohata, Sho, Mori, Tatsuhiro, Kondo, Yutaka, Sharma, Sangeeta, Hyvärinen, Antti, Andrews, Elisabeth, Tunved, Peter, Asmi, Eija, Backman, John, Servomaa, Henri, Veber, Daniel, Koike, Makoto, Kanaya, Yugo, Yoshida, Atsushi, Moteki, Nobuhiro, Zhao, Yongjing, Matsushita, Junji, Oshima, Naga, Eleftheriadis, Konstantinos, Vratolis, Stergios, Krejci, Radovan, Zieger, Paul, and Tobo, Yutaka
- Abstract
Long-term measurements of atmospheric mass concentrations of black carbon (BC) are needed to investigate changes in its emission, transport, and deposition. However, depending on instrumentation, parameters related to BC such as aerosol absorption coefficient (babs) have been measured instead. Most ground-based measurements of babs in the Arctic have been made by filter-based absorption photometers, including particle soot absorption photometers (PSAPs), continuous light absorption photometers (CLAPs), Aethalometers, and multi-angle absorption photometers (MAAPs). The measured babs can be converted to mass concentrations of BC (MBC) by assuming the value of the mass absorption cross section (MAC; MBC= babs/ MAC). However, the accuracy of conversion of babs to MBC has not been adequately assessed. Here, we introduce a systematic method for deriving MAC values from babs measured by these instruments and independently measured MBC. In this method, MBC was measured with a filter-based absorption photometer with a heated inlet (COSMOS). COSMOS-derived MBC (MBC (COSMOS)) is traceable to a rigorously calibrated single particle soot photometer (SP2), and the absolute accuracy of MBC (COSMOS) has been demonstrated previously to be about 15 % in Asia and the Arctic. The necessary conditions for application of this method are a high correlation of the measured babs with independently measured MBC and long-term stability of the regression slope, which is denoted as MACcor (MAC derived from the correlation). In general, babs–MBC (COSMOS) correlations were high (r2= 0.76–0.95 for hourly data) at Alert in Canada, Ny-Ålesund in Svalbard, Barrow (NOAA Barrow Observatory) in Alaska, Pallastunturi in Finland, and Fukue in Japan and stable for up to 10 years. We successfully estimated MACcor values (10.8–15.1 m2 g−1 at a wavelength of 550 nm for hourly data) for these instruments, and these MACcor values can be used to obtain error-constrained estimates of MBC from babs measured at the
- Published
- 2021
- Full Text
- View/download PDF
11. Intercomparison and characterization of 23 Aethalometers under laboratory and ambient air conditions: procedures and unit-to-unit variabilities
- Author
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Minguillón, María Cruz [0000-0002-5464-0391], Cuesta-Mosquera, Andrea, Močnik, Griša, Drinovec, Luka, Müller, Thomas, Pfeifer, Sascha, Minguillón, María Cruz, Briel, Björn, Buckley, Paul, Dudoitis, Vadimas, Fernández-García, Javier, Fernández-Amado, María, Ferreira De Brito, Joel, Riffault, Veronique, Flentje, Harald, Heffernan, Eimear, Kalivitis, Nikos, Kalogridis, Athina-Cerise, Keernik, Hannes, Marmureanu, Luminita, Luoma, Krista, Marinoni, Angela, Pikridas, Michael, Schauer, Gerhard, Serfozo, Norbert, Servomaa, Henri, Titos, Gloria, Yus-Díez, Jesús, Zioła, Natalia, Wiedensohler, Alfred, Minguillón, María Cruz [0000-0002-5464-0391], Cuesta-Mosquera, Andrea, Močnik, Griša, Drinovec, Luka, Müller, Thomas, Pfeifer, Sascha, Minguillón, María Cruz, Briel, Björn, Buckley, Paul, Dudoitis, Vadimas, Fernández-García, Javier, Fernández-Amado, María, Ferreira De Brito, Joel, Riffault, Veronique, Flentje, Harald, Heffernan, Eimear, Kalivitis, Nikos, Kalogridis, Athina-Cerise, Keernik, Hannes, Marmureanu, Luminita, Luoma, Krista, Marinoni, Angela, Pikridas, Michael, Schauer, Gerhard, Serfozo, Norbert, Servomaa, Henri, Titos, Gloria, Yus-Díez, Jesús, Zioła, Natalia, and Wiedensohler, Alfred
- Abstract
Aerosolized black carbon is monitored worldwide to quantify its impact on air quality and climate. Given its importance, measurements of black carbon mass concentrations must be conducted with instruments operating in quality-checked and ensured conditions to generate data which are reliable and comparable temporally and geographically. In this study, we report the results from the largest characterization and intercomparison of filter-based absorption photometers, the Aethalometer model AE33, belonging to several European monitoring networks. Under controlled laboratory conditions, a total of 23 instruments measured mass concentrations of black carbon from three well-characterized aerosol sources: synthetic soot, nigrosin particles, and ambient air from the urban background of Leipzig, Germany. The objective was to investigate the individual performance of the instruments and their comparability; we analyzed the response of the instruments to the different aerosol sources and the impact caused by the use of obsolete filter materials and the application of maintenance activities. Differences in the instrument-to-instrument variabilities from equivalent black carbon (eBC) concentrations reported at 880 nm were determined before maintenance activities (for soot measurements, average deviation from total least square regression was −2.0 % and the range −16 % to 7 %; for nigrosin measurements, average deviation was 0.4 % and the range −15 % to 17 %), and after they were carried out (for soot measurements, average deviation was −1.0 % and the range −14 % to 8 %; for nigrosin measurements, the average deviation was 0.5 % and the range −12 % to 15 %). The deviations are in most of the cases explained by the type of filter material employed by the instruments, the total particle load on the filter, and the flow calibration. The results of this intercomparison activity show that relatively small unit-to-unit variability of AE33-based particle light absorbing measurements is
- Published
- 2021
12. Intercomparison and characterization of 23 Aethalometers under laboratory and ambient air conditions: procedures and unit-to-unit variabilities
- Author
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Cuesta-Mosquera, Andrea, Mocnik, Griša, Drinovec, Luka, Müller, Thomas, Pfeifer, Sascha, Minguillón, María Cruz, Briel, Björn, Buckley, Paul, Dudoitis, Vadimas, Fernández-García, Javier, Fernández-Amado, María, Brito, Joel F. de, Riffault, Veronique, Flentje, Harald, Heffernan, Eimear, Kalivitis, Nikos, Kalogridis, Athina-Cerise, Keernik, Hannes, Marmureanu, Luminita, Luoma, Krista, Marinoni, Angela, Pikridas, Michael, Schauer, Gerhard, Serfozo, Norbert, Servomaa, Henri, Titos Vela, Gloria, Yus-Díez, Jesús, Zioła, Natalia, Wiedensohler, Alfred, Cuesta-Mosquera, Andrea, Mocnik, Griša, Drinovec, Luka, Müller, Thomas, Pfeifer, Sascha, Minguillón, María Cruz, Briel, Björn, Buckley, Paul, Dudoitis, Vadimas, Fernández-García, Javier, Fernández-Amado, María, Brito, Joel F. de, Riffault, Veronique, Flentje, Harald, Heffernan, Eimear, Kalivitis, Nikos, Kalogridis, Athina-Cerise, Keernik, Hannes, Marmureanu, Luminita, Luoma, Krista, Marinoni, Angela, Pikridas, Michael, Schauer, Gerhard, Serfozo, Norbert, Servomaa, Henri, Titos Vela, Gloria, Yus-Díez, Jesús, Zioła, Natalia, and Wiedensohler, Alfred
- Abstract
[Abstract]: Aerosolized black carbon is monitored worldwide to quantify its impact on air quality and climate. Given its importance, measurements of black carbon mass concentrations must be conducted with instruments operating in quality-checked and ensured conditions to generate data which are reliable and comparable temporally and geographically. In this study, we report the results from the largest characterization and intercomparison of filter-based absorption photometers, the Aethalometer model AE33, belonging to several European monitoring networks. Under controlled laboratory conditions, a total of 23 instruments measured mass concentrations of black carbon from three well-characterized aerosol sources: synthetic soot, nigrosin particles, and ambient air from the urban background of Leipzig, Germany. The objective was to investigate the individual performance of the instruments and their comparability; we analyzed the response of the instruments to the different aerosol sources and the impact caused by the use of obsolete filter materials and the application of maintenance activities. Differences in the instrument-to-instrument variabilities from equivalent black carbon (eBC) concentrations reported at 880 nm were determined before maintenance activities (for soot measurements, average deviation from total least square regression was −2.0 % and the range −16 % to 7 %; for nigrosin measurements, average deviation was 0.4 % and the range −15 % to 17 %), and after they were carried out (for soot measurements, average deviation was −1.0 % and the range −14 % to 8 %; for nigrosin measurements, the average deviation was 0.5 % and the range −12 % to 15 %). The deviations are in most of the cases explained by the type of filter material employed by the instruments, the total particle load on the filter, and the flow calibration. The results of this intercomparison activity show that relatively small unit-to-unit variability of AE33-based particle light absorbing meas
- Published
- 2021
13. Intercomparison and characterization of 23 Aethalometers under laboratory and ambient air conditions: procedures and unit-to-unit variabilities
- Author
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Cuesta-Mosquera, Andrea, primary, Močnik, Griša, additional, Drinovec, Luka, additional, Müller, Thomas, additional, Pfeifer, Sascha, additional, Minguillón, María Cruz, additional, Briel, Björn, additional, Buckley, Paul, additional, Dudoitis, Vadimas, additional, Fernández-García, Javier, additional, Fernández-Amado, María, additional, Ferreira De Brito, Joel, additional, Riffault, Veronique, additional, Flentje, Harald, additional, Heffernan, Eimear, additional, Kalivitis, Nikolaos, additional, Kalogridis, Athina-Cerise, additional, Keernik, Hannes, additional, Marmureanu, Luminita, additional, Luoma, Krista, additional, Marinoni, Angela, additional, Pikridas, Michael, additional, Schauer, Gerhard, additional, Serfozo, Norbert, additional, Servomaa, Henri, additional, Titos, Gloria, additional, Yus-Díez, Jesús, additional, Zioła, Natalia, additional, and Wiedensohler, Alfred, additional
- Published
- 2021
- Full Text
- View/download PDF
14. Estimates of mass absorption cross sections of black carbon for filter-based absorption photometers in the Arctic
- Author
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Ohata, Sho, primary, Mori, Tatsuhiro, additional, Kondo, Yutaka, additional, Sharma, Sangeeta, additional, Hyvärinen, Antti, additional, Andrews, Elisabeth, additional, Tunved, Peter, additional, Asmi, Eija, additional, Backman, John, additional, Servomaa, Henri, additional, Veber, Daniel, additional, Koike, Makoto, additional, Kanaya, Yugo, additional, Yoshida, Atsushi, additional, Moteki, Nobuhiro, additional, Zhao, Yongjing, additional, Matsushita, Junji, additional, and Oshima, Naga, additional
- Published
- 2020
- Full Text
- View/download PDF
15. Refurbishment of the HUTRAD system
- Author
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Lahtinen, Janne, primary, Uusitalo, Josu, additional, Servomaa, Henri, additional, Salo, Sampo, additional, Nguyen, Huy, additional, Pihlflyckt, Jorgen, additional, Havia, Kimmo, additional, Vaaja, Matti, additional, Rautiainen, Kimmo, additional, Praks, Jaan, additional, and Lemmetyinen, Juha, additional
- Published
- 2020
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- View/download PDF
16. Characterizing the Arctic absorbing aerosol with multi-instrument observations
- Author
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Asmi, Eija, primary, Backman, John, additional, Servomaa, Henri, additional, Virkkula, Aki, additional, Gini, Maria, additional, Eleftheriadis, Kostas, additional, Müller, Thomas, additional, Ohata, Sho, additional, Kondo, Yutaka, additional, and Hyvärinen, Antti, additional
- Published
- 2020
- Full Text
- View/download PDF
17. Intercomparison and characterization of 23 Aethalometers under laboratory and ambient air conditions: Procedures and unit-to-unit variabilities
- Author
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Cuesta-Mosquera, Andrea, primary, Močnik, Griša, additional, Drinovec, Luka, additional, Müller, Thomas, additional, Pfeifer, Sascha, additional, Minguillón, María Cruz, additional, Björn, Briel, additional, Buckley, Paul, additional, Dudoitis, Vadimas, additional, Fernández-García, Javier, additional, Fernández-Amado, María, additional, Ferreira De Brito, Joel, additional, Flentje, Harald, additional, Heffernan, Eimear, additional, Kalivitis, Nikolaos, additional, Kalogridis, Athina-Cerise, additional, Keernik, Hannes, additional, Marmureanu, Luminita, additional, Luoma, Krista, additional, Marinoni, Angela, additional, Pikridas, Michael, additional, Schauer, Gerhard, additional, Serfozo, Norbert, additional, Servomaa, Henri, additional, Titos, Gloria, additional, Yus-Díez, Jesús, additional, Zioła, Natalia, additional, and Wiedensohler, Alfred, additional
- Published
- 2020
- Full Text
- View/download PDF
18. Supplementary material to "Intercomparison and characterization of 23 Aethalometers under laboratory and ambient air conditions: Procedures and unit-to-unit variabilities"
- Author
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Cuesta-Mosquera, Andrea, primary, Močnik, Griša, additional, Drinovec, Luka, additional, Müller, Thomas, additional, Pfeifer, Sascha, additional, Minguillón, María Cruz, additional, Björn, Briel, additional, Buckley, Paul, additional, Dudoitis, Vadimas, additional, Fernández-García, Javier, additional, Fernández-Amado, María, additional, Ferreira De Brito, Joel, additional, Flentje, Harald, additional, Heffernan, Eimear, additional, Kalivitis, Nikolaos, additional, Kalogridis, Athina-Cerise, additional, Keernik, Hannes, additional, Marmureanu, Luminita, additional, Luoma, Krista, additional, Marinoni, Angela, additional, Pikridas, Michael, additional, Schauer, Gerhard, additional, Serfozo, Norbert, additional, Servomaa, Henri, additional, Titos, Gloria, additional, Yus-Díez, Jesús, additional, Zioła, Natalia, additional, and Wiedensohler, Alfred, additional
- Published
- 2020
- Full Text
- View/download PDF
19. Estimates of mass absorption cross sections of black carbon for filter-based absorption photometers in the Arctic.
- Author
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Sho Ohata, Tatsuhiro Mori, Yutaka Kondo, Sharma, Sangeeta, Antti Hyvärinen, Andrews, Elisabeth, Tunved, Peter, Asmi, Eija, Backman, John, Servomaa, Henri, Veber, Daniel, Makoto Koike, Yugo Kanaya, Atsushi Yoshida, Nobuhiro Moteki, Yongjing Zhao, Junji Matsushita, and Naga Oshima
- Abstract
Long-term measurements of black carbon (BC) are warranted for investigating changes in its emission, transport, and deposition. However, depending on instrumentation, parameters related to BC such as aerosol absorption coefficient (b
abs ) have been measured instead. Most ground-based measurements of babs in the Arctic have been made by filter-based absorption photometers, including multi-angle absorption photometers (MAAP), particle soot absorption photometers (PSAP), continuous light absorption photometer (CLAP), and Aethalometers. The measured babs can be converted to atmospheric mass concentrations of BC (MBC ) by assuming the value of the mass absorption cross section (MAC = babs /MBC ). However, the accuracy of conversion of babs to MBC has not been adequately assessed. Here, we introduce a systematic method for deriving MAC values from babs measured by these instruments and independently measured MBC . In this method, MBC was measured with a filter-based absorption photometer with a heated inlet (COSMOS). COSMOS- derived MBC (MBC (COSMOS)) is traceable to a rigorously calibrated single particle soot photometer (SP2) and the absolute accuracy of MBC (COSMOS) has been demonstrated previously to be about 15 % in Asia and the Arctic. The necessary conditions for application of this method are a high correlation of the measured babs with independently measured MBC , and long-term stability of the correlation slope, which represents the MAC. In general, babs - MBC (COSMOS) correlations were high (r² = 0.84-0.96 for hourly data) at Fukue in Japan, Barrow in Alaska, Ny-Ålesund in Svalbard, Pallastunturi in Finland, and Alert in Canada, and stable up to for 10 years. We successfully estimated MAC values (11.0-15.2 m² g-1 at a wavelength of 550 nm) for these instruments and these MAC values can be used to obtain error-constrained estimates of MBC from babs measured at these sites even in the past, when COSMOS measurements were not made. Because the absolute values of MBC in these Arctic sites estimated by this method are consistent with each other, they are applicable to study spatial and temporal variation of MBC and to evaluate performance of numerical model calculations. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
20. Characterizing the Arctic absorbing aerosol with multi-instrument observations.
- Author
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Asmi, Eija, Backman, John, Servomaa, Henri, Virkkula, Aki, Gini, Maria, Eleftheriadis, Kostas, Müller, Thomas, Sho Ohata, Yutaka Kondo, and Hyvärinen, Antti
- Subjects
AEROSOLS ,ABSORPTION coefficients ,GLOBAL warming ,AIR masses ,AIR flow ,CARBONACEOUS aerosols - Abstract
The Arctic absorbing aerosols have a high potential to accelerate global warming. Accurate and sensitive measurements of their concentrations, variability and atmospheric mixing are needed. Filter-based aerosol light absorption measurement methods are the most widely applied in the Arctic. Those will be the focus of this study. Aerosol light absorption was measured during one month field campaign in June–July 2019 at the Pallas Global AtmosphericWatch (GAW) station in northern Finland. The campaign provided a real-world test for different absorption measurement techniques supporting the goals of the EMPIR BC metrology project in developing aerosol absorption standard and reference methods. Very low aerosol concentrations prevailed during the campaign which imposed a challenge for the instruments detection. In this study we compare the results from five filter-based absorption techniques: Aethalometer models AE31 and AE33, Particle Soot Absorption Photometer (PSAP), Multi Angle Absorption Photometer (MAAP) and Continuous Soot Monitoring System (COSMOS), and from one indirect method called Extinction Minus Scattering (EMS). The sensitivity of the filter-based techniques was adequate to measure aerosol light absorption coefficients down to around 0.05 Mm
-1 levels. The average value measured during the campaign using MAAP was 0.09 Mm-1 (at wavelength of 637 nm). When data were averaged for >1h, an agreement of around 20% was obtained between instruments. COSMOS measured systematically the lowest absorption coefficient values, which was expected due to the sample pre-treatment in COSMOS inlet. PSAP showed the best linear correlation with MAAP (R2 = 0.85), followed by AE33 and COSMOS (R2 = 0.84). The noisy data from AE31 resulted in a slightly lower, yet a significant, correlation with MAAP (R2 = 0.46). In contrast to the filter-based techniques, the sensitivity of the indirect EMS method to measure aerosol absorption was not adequate at such low concentrations levels. An absorption coefficient on the order of >1 Mm-1 was estimated as the lowest limit, to reliably distinguish the signal from the noise. Throughout the campaign the aerosol was highly scattering with an average single-scattering albedo of 0.97. Two different air-mass origins could be identified: the north-east and from the north-west. The north-eastern air masses contained higher fraction of thickly coated light absorbing particles than the westerly air masses. Aerosol scattering, absorption and the particle coating thickness increased on the last ten days of the campaign during the north-eastern air flow. The simultaneous changes in aerosol source region, mixing state, concentration and particle optical size were reflected in the instruments' response in a complex way. The observed decrease in aerosol size suggested additional activation of secondary particle formation mechanisms. The results demonstrate the challenges encountered in the Arctic absorbing aerosol measurements. The applicability and uncertainties of different techniques are discussed and new knowledge on the absorbing aerosol characteristics in summer Arctic air masses reference to the source region is provided. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
21. Remote Sensing of Water Bodies Using Multisource Data
- Author
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Pulliainen, Jouni, Teknillinen korkeakoulu, Helsinki University of Technology, Sähkö- ja tietoliikennetekniikan osasto, Hallikainen, Martti, Servomaa, Henri, Pulliainen, Jouni, Teknillinen korkeakoulu, Helsinki University of Technology, Sähkö- ja tietoliikennetekniikan osasto, Hallikainen, Martti, and Servomaa, Henri
- Published
- 1997
22. A semi-operative approach to lake water quality retrieval from remote sensing data
- Author
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Pulliainen, Jouni, primary, Kallio, Kari, additional, Eloheimo, Karri, additional, Koponen, Sampsa, additional, Servomaa, Henri, additional, Hannonen, Tuula, additional, Tauriainen, Simo, additional, and Hallikainen, Martti, additional
- Published
- 2001
- Full Text
- View/download PDF
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