Articles | Volume 14, issue 7
https://doi.org/10.5194/amt-14-4879-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-14-4879-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
10 Jul 2021
Research article |
| 10 Jul 2021
| 10 Jul 2021
New correction method for the scattering coefficient measurements of a three-wavelength nephelometer
Jie Qiu
Department of Atmospheric and Oceanic Sciences, School of Physics,
Peking University, Beijing 100871, China
Wangshu Tan
Department of Atmospheric and Oceanic Sciences, School of Physics,
Peking University, Beijing 100871, China
School of Optics and Photonics, Beijing Institute of Technology,
Beijing 100081, China
Gang Zhao
Department of Atmospheric and Oceanic Sciences, School of Physics,
Peking University, Beijing 100871, China
State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking
University, Beijing 100871, China
Yingli Yu
Economics & Technology Research Institute, China National Petroleum Corporation, Beijing 100724, China
Department of Atmospheric and Oceanic Sciences, School of Physics,
Peking University, Beijing 100871, China
Chunsheng Zhao
CORRESPONDING AUTHOR
Department of Atmospheric and Oceanic Sciences, School of Physics,
Peking University, Beijing 100871, China
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EGUsphere, https://doi.org/10.5194/egusphere-2025-1410, https://doi.org/10.5194/egusphere-2025-1410, 2025
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This study provides direct observational evidence that secondary organic aerosols have substantially higher real refractive indices than primary organic aerosols, challenging current model assumptions and offering recommended values that improve the accuracy of aerosol radiative effect simulations.
Ye Kuang, Jiangchuan Tao, Hanbing Xu, Li Liu, Pengfei Liu, Wanyun Xu, Weiqi Xu, Yele Sun, and Chunsheng Zhao
Atmos. Chem. Phys., 25, 1163–1174, https://doi.org/10.5194/acp-25-1163-2025, https://doi.org/10.5194/acp-25-1163-2025, 2025
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This study presents a novel optical framework to measure supersaturation, a fundamental parameter in cloud physics, by observing the scattering properties of particles that have or have not grown into cloud droplets. The technique offers high-resolution measurements, capturing essential fluctuations in supersaturation necessary for understanding cloud physics.
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Marine aerosols play a critical role in weather and climate and their real part of the refractive index (RRI) is a key factor in their radiative effects. We present a study of RRI measurements using optical tweezers technology and find the calculated results of RRI using traditional method disagree with the measurements. A parameterization of the RRI and relative humidity relationship is proposed and it will improve the radiation calculation in numerical models.
Bishuo He and Chunsheng Zhao
EGUsphere, https://doi.org/10.5194/egusphere-2024-3441, https://doi.org/10.5194/egusphere-2024-3441, 2024
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Factor-uncertainty analysis helps us understand their impacts on complex systems. Traditional methods have many limitations. This study introduces a new method to measure how each factor contributes to uncertainty. It gains insights into the role of each variable and works for all multi-factor systems. As an application, we analyzed how aerosols affect solar radiation and identified the key factors. These analyses can improve our understanding of the role of aerosols in climate change.
Rongzheng Cao, Siying Chen, Wangshu Tan, Yixuan Xie, He Chen, Pan Guo, Rui Hu, Yinghong Yu, Jie Yu, and Shusen Yao
EGUsphere, https://doi.org/10.5194/egusphere-2024-2650, https://doi.org/10.5194/egusphere-2024-2650, 2024
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This study applied two density-based clustering algorithms to the quality control of temperature data from Raman lidar. Three automated methods were proposed, achieving automation in data quality control. The effectiveness of these three methods was verified using Raman temperature lidar data and ERA5 data from the past three years. Compared with the previous method, they have great improvements. Additionally, factors affecting the quality control results were further analyzed.
Jiangchuan Tao, Biao Luo, Weiqi Xu, Gang Zhao, Hanbin Xu, Biao Xue, Miaomiao Zhai, Wanyun Xu, Huarong Zhao, Sanxue Ren, Guangsheng Zhou, Li Liu, Ye Kuang, and Yele Sun
Atmos. Chem. Phys., 24, 9131–9154, https://doi.org/10.5194/acp-24-9131-2024, https://doi.org/10.5194/acp-24-9131-2024, 2024
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Using simultaneous measurements of DMA–CCNC, H(/V)TDMA, and DMA–SP2, impacts of primary emissions and secondary aerosol formations on changes in aerosol physicochemical properties were comprehensively investigated. It was found that intercomparisons among aerosol mixing-state parameters derived from different techniques can help us gain more insight into aerosol physical properties which, in turn, will aid the investigation of emission characteristics and secondary aerosol formation pathways.
Weilun Zhao, Ying Li, Gang Zhao, Song Guo, Nan Ma, Shuya Hu, and Chunsheng Zhao
Atmos. Chem. Phys., 23, 14889–14902, https://doi.org/10.5194/acp-23-14889-2023, https://doi.org/10.5194/acp-23-14889-2023, 2023
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Studies have concentrated on particles containing black carbon (BC) smaller than 700 nm because of technical limitations. In this study, BC-containing particles larger than 700 nm (BC>700) were measured, highlighting their importance to total BC mass and absorption. The contribution of BC>700 to the BC direct radiative effect was estimated, highlighting the necessity to consider the whole size range of BC-containing particles in the model estimation of BC radiative effects.
Fei Li, Biao Luo, Miaomiao Zhai, Li Liu, Gang Zhao, Hanbing Xu, Tao Deng, Xuejiao Deng, Haobo Tan, Ye Kuang, and Jun Zhao
Atmos. Chem. Phys., 23, 6545–6558, https://doi.org/10.5194/acp-23-6545-2023, https://doi.org/10.5194/acp-23-6545-2023, 2023
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A field campaign was conducted to study black carbon (BC) mass size distributions and mixing states connected to traffic emissions using a system that combines a differential mobility analyzer and single-particle soot photometer. Results showed that the black carbon content of traffic emissions has a considerable influence on both BC mass size distributions and mixing states, which has crucial implications for accurately representing BC from various sources in regional and climate models.
Liang Yuan and Chunsheng Zhao
Atmos. Chem. Phys., 23, 3195–3205, https://doi.org/10.5194/acp-23-3195-2023, https://doi.org/10.5194/acp-23-3195-2023, 2023
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Chemical compositions vary between and within particles due to the complex sources and aging processes, causing particle-to-particle heterogeneity in aerosol hygroscopicity, which is of great importance to aerosol climatic and environmental effects. This study proposes an algorithm to quantify the heterogeneity from in situ measurements, sheds light on the reanalysis of the existing H-TDMA datasets, and could have a large impact on how we use and think about these datasets.
Weilun Zhao, Gang Zhao, Ying Li, Song Guo, Nan Ma, Lizi Tang, Zirui Zhang, and Chunsheng Zhao
Atmos. Meas. Tech., 15, 6807–6817, https://doi.org/10.5194/amt-15-6807-2022, https://doi.org/10.5194/amt-15-6807-2022, 2022
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A new method to determine black carbon mass size distribution (BCMSD) was proposed using the size-resolved absorption coefficient measured by an aerodynamic aerosol classifier in tandem with an aethalometer. This new method fills the gap in the high-time-resolution measurement of BCMSD ranging from upper submicron particle sizes to larger than 1 µm. This method can be applied to field measurement of BCMSD extensively for better understanding BC aging and better estimating the BC climate effect.
Gang Zhao, Tianyi Tan, Shuya Hu, Zhuofei Du, Dongjie Shang, Zhijun Wu, Song Guo, Jing Zheng, Wenfei Zhu, Mengren Li, Limin Zeng, and Min Hu
Atmos. Chem. Phys., 22, 10861–10873, https://doi.org/10.5194/acp-22-10861-2022, https://doi.org/10.5194/acp-22-10861-2022, 2022
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Black carbon is the second strongest absorbing component in the atmosphere that exerts warming effects on climate. One critical challenge in quantifying the ambient black carbon's radiative effects is addressing the BC microphysical properties. In this study, the microphysical properties of the aged and fresh BC particles are synthetically analyzed under different atmospheres. The measurement results can be further used in models to help constrain the uncertainties of the BC radiative effects.
Gang Zhao, Tianyi Tan, Yishu Zhu, Min Hu, and Chunsheng Zhao
Atmos. Chem. Phys., 21, 18055–18063, https://doi.org/10.5194/acp-21-18055-2021, https://doi.org/10.5194/acp-21-18055-2021, 2021
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In this study, the black carbon (BC) mixing state index (χ) is developed to quantify the dispersion of ambient black carbon aerosol mixing states based on binary systems of BC and other non-black carbon components. We demonstrate that the BC light absorption enhancement increases with χ for the same MR, which indicates that χ can be employed as a factor to constrain the light absorption enhancement of ambient BC.
Siying Chen, Rongzheng Cao, Yixuan Xie, Yinchao Zhang, Wangshu Tan, He Chen, Pan Guo, and Peitao Zhao
Atmos. Chem. Phys., 21, 11489–11504, https://doi.org/10.5194/acp-21-11489-2021, https://doi.org/10.5194/acp-21-11489-2021, 2021
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Gang Zhao, Yishu Zhu, Zhijun Wu, Taomou Zong, Jingchuan Chen, Tianyi Tan, Haichao Wang, Xin Fang, Keding Lu, Chunsheng Zhao, and Min Hu
Atmos. Chem. Phys., 21, 9995–10004, https://doi.org/10.5194/acp-21-9995-2021, https://doi.org/10.5194/acp-21-9995-2021, 2021
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New particle formation is thought to contribute half of the global cloud condensation nuclei. We find that the new particle formation is more likely to happen in the upper boundary layer than that at the ground, which can be partially explained by the aerosol–radiation interaction. Our study emphasizes the influence of aerosol–radiation interaction on the NPF.
Tianyi Tan, Min Hu, Zhuofei Du, Gang Zhao, Dongjie Shang, Jing Zheng, Yanhong Qin, Mengren Li, Yusheng Wu, Limin Zeng, Song Guo, and Zhijun Wu
Atmos. Chem. Phys., 21, 8499–8510, https://doi.org/10.5194/acp-21-8499-2021, https://doi.org/10.5194/acp-21-8499-2021, 2021
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Every year in the pre-monsoon season, the black carbon (BC) aerosols originated from biomass burning in southern Asia are easily transported to the Tibetan Plateau (TP) by the convenience of westerly wind. This study reveals that the BC aerosols in the aged biomass burning plumes strongly enhance the total light absorption over the TP, and the aging process during the long-range transport will further strengthen the radiative heating of those BC aerosols.
Weilun Zhao, Wangshu Tan, Gang Zhao, Chuanyang Shen, Yingli Yu, and Chunsheng Zhao
Atmos. Meas. Tech., 14, 1319–1331, https://doi.org/10.5194/amt-14-1319-2021, https://doi.org/10.5194/amt-14-1319-2021, 2021
Chuanyang Shen, Gang Zhao, and Chunsheng Zhao
Atmos. Meas. Tech., 14, 1293–1301, https://doi.org/10.5194/amt-14-1293-2021, https://doi.org/10.5194/amt-14-1293-2021, 2021
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Aerosol hygroscopicity measured by the humidified tandem differential mobility analyzer (HTDMA) is affected by multiply charged particles from two aspects: (1) number contribution and (2) the weakening effect. An algorithm is proposed to do the multi-charge correction and applied to a field measurement. Results show that the difference between corrected and measured size-resolved κ can reach 0.05, highlighting that special attention needs to be paid to the multi-charge effect when using HTDMA.
Chuanyang Shen, Gang Zhao, Weilun Zhao, Ping Tian, and Chunsheng Zhao
Atmos. Chem. Phys., 21, 1375–1388, https://doi.org/10.5194/acp-21-1375-2021, https://doi.org/10.5194/acp-21-1375-2021, 2021
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Submicron particles larger than 300 nm dominate the aerosol light extinction and mass concentration in the urban environment. Aerosol hygroscopic properties extended to 600 nm were investigated at an urban site. Our results find that there exists a large fraction of a less hygroscopic group above 300 nm, and the hygroscopicity in this size range is enhanced significantly with the development of pollution levels. The hygroscopicity variation contributes greatly to the low visibility.
Quan Liu, Dantong Liu, Qian Gao, Ping Tian, Fei Wang, Delong Zhao, Kai Bi, Yangzhou Wu, Shuo Ding, Kang Hu, Jiale Zhang, Deping Ding, and Chunsheng Zhao
Atmos. Chem. Phys., 20, 3931–3944, https://doi.org/10.5194/acp-20-3931-2020, https://doi.org/10.5194/acp-20-3931-2020, 2020
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We present a series of aircraft-based in situ measurements of aerosol chemical components and size distributions over the North China Plain, and the hygroscopicity is derived from aerosol chemical composition. These results reveal the vertical characteristics of aerosol hygroscopicity, and we investigated their impacts on optical properties and activation under different moisture and pollution conditions over this polluted region.
Tianning Su, Zhanqing Li, Chengcai Li, Jing Li, Wenchao Han, Chuanyang Shen, Wangshu Tan, Jing Wei, and Jianping Guo
Atmos. Chem. Phys., 20, 3713–3724, https://doi.org/10.5194/acp-20-3713-2020, https://doi.org/10.5194/acp-20-3713-2020, 2020
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We study the role of aerosol vertical distribution in thermodynamic stability and PBL development. Under different aerosol vertical structures, the diurnal cycles of PBLH and PM2.5 show distinct characteristics. Large differences in the heating rate affect atmospheric buoyancy and stability differently under different aerosol structures. As a result, the aerosol–PBL interaction can be strengthened by the inverse aerosol structure and potentially neutralized by the decreasing structure.
Ping Tian, Dantong Liu, Delong Zhao, Chenjie Yu, Quan Liu, Mengyu Huang, Zhaoze Deng, Liang Ran, Yunfei Wu, Shuo Ding, Kang Hu, Gang Zhao, Chunsheng Zhao, and Deping Ding
Atmos. Chem. Phys., 20, 2603–2622, https://doi.org/10.5194/acp-20-2603-2020, https://doi.org/10.5194/acp-20-2603-2020, 2020
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This study paints a full picture of the evolution of vertical characteristics of aerosol optical properties and shortwave heating impacts of carbonaceous aerosols during different stages of pollution events over the Beijing region and highlights the increased contribution of brown carbon absorption, especially at higher levels, during pollution.
Yu Wang, Ying Chen, Zhijun Wu, Dongjie Shang, Yuxuan Bian, Zhuofei Du, Sebastian H. Schmitt, Rong Su, Georgios I. Gkatzelis, Patrick Schlag, Thorsten Hohaus, Aristeidis Voliotis, Keding Lu, Limin Zeng, Chunsheng Zhao, M. Rami Alfarra, Gordon McFiggans, Alfred Wiedensohler, Astrid Kiendler-Scharr, Yuanhang Zhang, and Min Hu
Atmos. Chem. Phys., 20, 2161–2175, https://doi.org/10.5194/acp-20-2161-2020, https://doi.org/10.5194/acp-20-2161-2020, 2020
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Severe haze events, with high particulate nitrate (pNO3−) burden, frequently prevail in Beijing. In this study, we demonstrate a mutual-promotion effect between aerosol water uptake and pNO3− formation backed up by theoretical calculations and field observations throughout a typical pNO3−-dominated haze event in Beijing wintertime. This self-amplified mutual-promotion effect between aerosol water content and particulate nitrate can rapidly deteriorate air quality and degrade visibility.
Ye Kuang, Yao He, Wanyun Xu, Pusheng Zhao, Yafang Cheng, Gang Zhao, Jiangchuan Tao, Nan Ma, Hang Su, Yanyan Zhang, Jiayin Sun, Peng Cheng, Wenda Yang, Shaobin Zhang, Cheng Wu, Yele Sun, and Chunsheng Zhao
Atmos. Chem. Phys., 20, 865–880, https://doi.org/10.5194/acp-20-865-2020, https://doi.org/10.5194/acp-20-865-2020, 2020
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A new method was developed to calculate hygroscopicity parameter κ of organic aerosols (κOA) based on aerosol light-scattering measurements and bulk aerosol chemical-composition measurements. Derived high-time-resolution κOA varied in a wide range (near 0 to 0.25), and the organic aerosol oxidation degree significantly impacts variations in κOA. Distinct diurnal variation in κOA is found, and its relationship with oxygenated organic aerosol is discussed.
Gang Zhao, Jiangchuan Tao, Ye Kuang, Chuanyang Shen, Yingli Yu, and Chunsheng Zhao
Atmos. Chem. Phys., 19, 13175–13188, https://doi.org/10.5194/acp-19-13175-2019, https://doi.org/10.5194/acp-19-13175-2019, 2019
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Characteristics of the black carbon size distribution (BCMSD) are studied by using our developed measurement system. Results show that the BCMSDs have two modes and the mean peak diameters are 150 nm and 503 nm, respectively. The coarser mode varies significantly under different pollution conditions, which gives rise to significant variation in aerosol bulk optical properties. Our study reveals that the BCMSD as well as the mixing state in estimating aerosol radiative forcing matters.
Gang Zhao, Tianyi Tan, Weilun Zhao, Song Guo, Ping Tian, and Chunsheng Zhao
Atmos. Chem. Phys., 19, 12875–12885, https://doi.org/10.5194/acp-19-12875-2019, https://doi.org/10.5194/acp-19-12875-2019, 2019
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Traditionally, the real part of the refractive index (RRI) of ambient aerosols is calculated by their chemical components. In this study, we demonstrate that the RRI is highly related to effective density rather than chemical components using field measurements. For the first time, a parameterization scheme for ambient aerosol RRI using effective density is proposed. This simple scheme is more reliable and ready to use in the calculation of aerosol optics and radiation.
Wanyun Xu, Ye Kuang, Chunsheng Zhao, Jiangchuan Tao, Gang Zhao, Yuxuan Bian, Wen Yang, Yingli Yu, Chuanyang Shen, Linlin Liang, Gen Zhang, Weili Lin, and Xiaobin Xu
Atmos. Chem. Phys., 19, 10557–10570, https://doi.org/10.5194/acp-19-10557-2019, https://doi.org/10.5194/acp-19-10557-2019, 2019
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The study of HONO, the primary source of OH radicals, is crucial for atmospheric photochemistry and heterogeneous chemistry. Heterogeneous NO2 conversion was shown to be one of the missing sources of HONO on the North China Plain, but the reaction path is still under debate. In this work, evidence was found that NH3 was the key factor that promoted the hydrolysis of NO2, leading to the explosive growth of HONO and nitrate, suggesting that NH3 emission control measures are urgently needed.
Wangshu Tan, Gang Zhao, Yingli Yu, Chengcai Li, Jian Li, Ling Kang, Tong Zhu, and Chunsheng Zhao
Atmos. Meas. Tech., 12, 3825–3839, https://doi.org/10.5194/amt-12-3825-2019, https://doi.org/10.5194/amt-12-3825-2019, 2019
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A new method to retrieve CCN number concentrations using multiwavelength Raman lidars is proposed. The method implements hygroscopic enhancements of backscatter and extinction with relative humidity to represent particle hygroscopicity. The retrieved CCN number concentrations are in good agreement with theoretical calculated values. Sensitivity tests indicate that retrieval error in CCN arises mostly from uncertainties in extinction coefficients and RH profiles.
Gang Zhao, Weilun Zhao, and Chunsheng Zhao
Atmos. Meas. Tech., 12, 3541–3550, https://doi.org/10.5194/amt-12-3541-2019, https://doi.org/10.5194/amt-12-3541-2019, 2019
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A new method is proposed to retrieve the size-resolved real part of the refractive index (RRI). The main principle of deriving the RRI is measuring the scattering intensity by a single-particle soot photometer of a size-selected aerosol. This method is validated by a series of calibration experiments using the components of the known RI. The retrieved size-resolved RRI covers a wide range, from 200 nm to 450 nm, with uncertainty of less than 0.02.
Gang Zhao, Chunsheng Zhao, Ye Kuang, Yuxuan Bian, Jiangchuan Tao, Chuanyang Shen, and Yingli Yu
Atmos. Chem. Phys., 18, 9049–9060, https://doi.org/10.5194/acp-18-9049-2018, https://doi.org/10.5194/acp-18-9049-2018, 2018
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The aerosol asymmetry factor (g) is one of the most important factors for assessing direct aerosol radiative forcing (DARF) and remote sensing. So far, few studies have focused on the measurements and parameterization of g. Our study shows that relative humidity has significant impacts on g and DARF due to aerosol hygroscopic growth. For the first time, a novel method based on measurements from the humidified nephelometer system is proposed to calculate g accurately with high time resolution.
Ye Kuang, Chun Sheng Zhao, Gang Zhao, Jiang Chuan Tao, Wanyun Xu, Nan Ma, and Yu Xuan Bian
Atmos. Meas. Tech., 11, 2967–2982, https://doi.org/10.5194/amt-11-2967-2018, https://doi.org/10.5194/amt-11-2967-2018, 2018
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Aerosol water has become an important topic recently because of its implications for multiphase secondary aerosol formation during severe haze events in Asia. This is a timely paper on this topic; a novel method is proposed to calculate ambient aerosol liquid water contents based only on measurements of a three-wavelength humidified nephelometer system. The advantage of this method is that this technique can provide continuous measurements of the changing ambient conditions.
Jing Li, Chengcai Li, and Chunsheng Zhao
Atmos. Chem. Phys., 18, 3289–3298, https://doi.org/10.5194/acp-18-3289-2018, https://doi.org/10.5194/acp-18-3289-2018, 2018
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Our study investigates the long-term trends of extreme aerosol pollution in China over the past ~ 30 years. In the 1980s, an overall positive trend is found throughout China with the extreme trend exceeding the mean trend, except for Northwest China and the North China Plain. In the 1990s, the extreme trends continued to dominate in the south while they yield to the mean trend in the north. After 2000, the extreme trend became weaker than the mean trend overall.
Jiangchuan Tao, Chunsheng Zhao, Ye Kuang, Gang Zhao, Chuanyang Shen, Yingli Yu, Yuxuan Bian, and Wanyun Xu
Atmos. Meas. Tech., 11, 895–906, https://doi.org/10.5194/amt-11-895-2018, https://doi.org/10.5194/amt-11-895-2018, 2018
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Existing chamber technologies for direct measurements of number concentration of cloud condensation nuclei (NCCN) are sophisticated and expensive. In this paper, a new method is proposed to calculate NCCN based only on measurements of a humidified nephelometer system which have accounted for influences of both aerosol size and aerosol hygroscopicity on NCCN calculation. This new method makes NCCN measurements more convenient and is capable of obtaining NCCN at lower supersaturations.
Gang Zhao, Chunsheng Zhao, Ye Kuang, Jiangchuan Tao, Wangshu Tan, Yuxuan Bian, Jing Li, and Chengcai Li
Atmos. Chem. Phys., 17, 12133–12143, https://doi.org/10.5194/acp-17-12133-2017, https://doi.org/10.5194/acp-17-12133-2017, 2017
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In this paper, influences of aerosol hygroscopic growth on the lidar ratio are studied. Results indicate that both the magnitude and vertical structures of the retrieved aerosol extinction coefficient (σext) profile from lidar signals are significantly biased. This study proposes a feasible method for reducing the bias of retrieving the σext profile and this method can be implemented in operational retrieval of the aerosol σext profile and for pollution monitoring.
Yuxuan Bian, Chunsheng Zhao, Wanyun Xu, Gang Zhao, Jiangchuan Tao, and Ye Kuang
Atmos. Meas. Tech., 10, 2313–2322, https://doi.org/10.5194/amt-10-2313-2017, https://doi.org/10.5194/amt-10-2313-2017, 2017
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Aerosol phase function is crucial for understanding the climate effects of aerosols. So far, there is a lack of instruments for measuring the aerosol phase function directly and accurately in laboratory studies and in situ measurements. A novel portable instrument with high angular range and resolution named
charge-coupled device-laser aerosol detective system(CCD-LADS) has been developed and validated for the measurement of the phase function of ambient aerosols in this study.
Ye Kuang, Chunsheng Zhao, Jiangchuan Tao, Yuxuan Bian, Nan Ma, and Gang Zhao
Atmos. Chem. Phys., 17, 6651–6662, https://doi.org/10.5194/acp-17-6651-2017, https://doi.org/10.5194/acp-17-6651-2017, 2017
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A novel approach is proposed in this research to derive the aerosol hygroscopicity parameter based only on measurements from a humidified nephelometer system without any additional information about particle number size distribution and black carbon. New findings in this research can bridge the gap between κ-Köhler theory and the aerosol light-scattering enhancement factor and will make the humidified nephelometer system more convenient when it comes to aerosol hygroscopicity research.
Nan Ma, Chunsheng Zhao, Jiangchuan Tao, Zhijun Wu, Simonas Kecorius, Zhibin Wang, Johannes Größ, Hongjian Liu, Yuxuan Bian, Ye Kuang, Monique Teich, Gerald Spindler, Konrad Müller, Dominik van Pinxteren, Hartmut Herrmann, Min Hu, and Alfred Wiedensohler
Atmos. Chem. Phys., 16, 8593–8607, https://doi.org/10.5194/acp-16-8593-2016, https://doi.org/10.5194/acp-16-8593-2016, 2016
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New particle formation (NPF) is one of main sources of cloud condensation nuclei (CCN) in the atmosphere. Based on in situ measurements, we found that CCN activity of newly formed particles largely differs in different NPF events. It is therefore difficult to find a simple parameterization of CCN activity for NPF events. Using a fixed size-resolved activation ratio curve or critical diameter is very likely to result in large biases up to 50 % in the calculated NCCN during NPF events.
Y. Kuang, C. S. Zhao, J. C. Tao, and N. Ma
Atmos. Chem. Phys., 15, 5761–5772, https://doi.org/10.5194/acp-15-5761-2015, https://doi.org/10.5194/acp-15-5761-2015, 2015
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In this paper, it is found that the diurnal variations of single scattering albedo (SSA) and asymmetry factor (g) for ambient aerosol are both evident and far different from those of dry state aerosol in the North China Plain (NCP. The diurnal changes of SSA and g have significant impacts on the estimation of daily average direct aerosol radiative effect (DARE) at the top of the atmosphere. In addition, several suggestions are proposed to improve the accurate prediction of DARE in the NCP.
J. Huang, H. Liu, J. H. Crawford, C. Chan, D. B. Considine, Y. Zhang, X. Zheng, C. Zhao, V. Thouret, S. J. Oltmans, S. C. Liu, D. B. A. Jones, S. D. Steenrod, and M. R. Damon
Atmos. Chem. Phys., 15, 5161–5179, https://doi.org/10.5194/acp-15-5161-2015, https://doi.org/10.5194/acp-15-5161-2015, 2015
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High ozone concentrations (up to 94.7ppbv) were frequently observed at an altitude of ~1.5--2km over Beijing during April--May 2005. Ozone due to Asian anthropogenic pollution made major contributions to the observed ozone enhancements. These enhancements typically occurred under southerly wind and warmer conditions. An earlier onset of the Asian summer monsoon would cause more ozone enhancement events in the lower troposphere over the North China Plain in late spring and early summer.
J. C. Tao, C. S. Zhao, N. Ma, and P. F. Liu
Atmos. Chem. Phys., 14, 12055–12067, https://doi.org/10.5194/acp-14-12055-2014, https://doi.org/10.5194/acp-14-12055-2014, 2014
G. Q. Fu, W. Y. Xu, R. F. Yang, J. B. Li, and C. S. Zhao
Atmos. Chem. Phys., 14, 11949–11958, https://doi.org/10.5194/acp-14-11949-2014, https://doi.org/10.5194/acp-14-11949-2014, 2014
J. Chen, C. S. Zhao, N. Ma, and P. Yan
Atmos. Chem. Phys., 14, 8105–8118, https://doi.org/10.5194/acp-14-8105-2014, https://doi.org/10.5194/acp-14-8105-2014, 2014
W. Y. Xu, C. S. Zhao, L. Ran, W. L. Lin, P. Yan, and X. B. Xu
Atmos. Chem. Phys., 14, 7757–7768, https://doi.org/10.5194/acp-14-7757-2014, https://doi.org/10.5194/acp-14-7757-2014, 2014
Y. X. Bian, C. S. Zhao, N. Ma, J. Chen, and W. Y. Xu
Atmos. Chem. Phys., 14, 6417–6426, https://doi.org/10.5194/acp-14-6417-2014, https://doi.org/10.5194/acp-14-6417-2014, 2014
N. Ma, W. Birmili, T. Müller, T. Tuch, Y. F. Cheng, W. Y. Xu, C. S. Zhao, and A. Wiedensohler
Atmos. Chem. Phys., 14, 6241–6259, https://doi.org/10.5194/acp-14-6241-2014, https://doi.org/10.5194/acp-14-6241-2014, 2014
H. J. Liu, C. S. Zhao, B. Nekat, N. Ma, A. Wiedensohler, D. van Pinxteren, G. Spindler, K. Müller, and H. Herrmann
Atmos. Chem. Phys., 14, 2525–2539, https://doi.org/10.5194/acp-14-2525-2014, https://doi.org/10.5194/acp-14-2525-2014, 2014
Z. Z. Deng, C. S. Zhao, N. Ma, L. Ran, G. Q. Zhou, D. R. Lu, and X. J. Zhou
Atmos. Chem. Phys., 13, 6227–6237, https://doi.org/10.5194/acp-13-6227-2013, https://doi.org/10.5194/acp-13-6227-2013, 2013
Related subject area
Subject: Aerosols | Technique: In Situ Measurement | Topic: Data Processing and Information Retrieval
Inversion algorithm of black carbon mixing state based on machine learning
Performance evaluation of Atmotube PRO sensors for air quality measurements in an urban location
Development and validation of a NOx+ ratio method for the quantitative separation of inorganic and organic nitrate aerosol using CV-UMR-ToF-ACSM
Retrieval of Bulk Hygroscopicity From PurpleAir PM2.5 Sensor Measurements
Spatial analysis of PM2.5 using a concentration similarity index applied to air quality sensor networks
A novel probabilistic source apportionment approach: Bayesian auto-correlated matrix factorization
Towards a hygroscopic growth calibration for low-cost PM2.5 sensors
Enhancing characterization of organic nitrogen components in aerosols and droplets using high-resolution aerosol mass spectrometry
Machine learning approaches for automatic classification of single-particle mass spectrometry data
A searchable database and mass spectral comparison tool for the Aerosol Mass Spectrometer (AMS) and the Aerosol Chemical Speciation Monitor (ACSM)
Numerical investigation on retrieval errors of mixing states of fractal black carbon aerosols using single-particle soot photometer based on Mie scattering and the effects on radiative forcing estimation
Performance evaluation of MOMA (MOment MAtching) – a remote network calibration technique for PM2.5 and PM10 sensors
Mapping the performance of a versatile water-based condensation particle counter (vWCPC) with numerical simulation and experimental study
Development and evaluation of an improved offline aerosol mass spectrometry technique
SMEARcore – modular data infrastructure for atmospheric measurement stations
A multiple-charging correction algorithm for a broad-supersaturation scanning cloud condensation nuclei (BS2-CCN) system
An evaluation of the U.S. EPA's correction equation for PurpleAir sensor data in smoke, dust, and wintertime urban pollution events
Typhoon-associated air quality over the Guangdong–Hong Kong–Macao Greater Bay Area, China: machine-learning-based prediction and assessment
Quantification of primary and secondary organic aerosol sources by combined factor analysis of extractive electrospray ionisation and aerosol mass spectrometer measurements (EESI-TOF and AMS)
A new method for calculating average visibility from the relationship between extinction coefficient and visibility
In situ particle sampling relationships to surface and turbulent fluxes using large eddy simulations with Lagrangian particles
The effect of the averaging period for PMF analysis of aerosol mass spectrometer measurements during offline applications
Calibrating networks of low-cost air quality sensors
Source apportionment resolved by time of day for improved deconvolution of primary source contributions to air pollution
Information content and aerosol property retrieval potential for different types of in situ polar nephelometer data
Rolling vs. seasonal PMF: real-world multi-site and synthetic dataset comparison
Comprehensive detection of analytes in large chromatographic datasets by coupling factor analysis with a decision tree
Combined organic and inorganic source apportionment on yearlong ToF-ACSM dataset at a suburban station in Athens
Retrieval of the sea spray aerosol mode from submicron particle size distributions and supermicron scattering during LASIC
Automated identification of local contamination in remote atmospheric composition time series
Ch3MS-RF: a random forest model for chemical characterization and improved quantification of unidentified atmospheric organics detected by chromatography–mass spectrometry techniques
Regularized inversion of aerosol hygroscopic growth factor probability density function: application to humidity-controlled fast integrated mobility spectrometer measurements
A systematic re-evaluation of methods for quantification of bulk particle-phase organic nitrates using real-time aerosol mass spectrometry
Revisiting matrix-based inversion of scanning mobility particle sizer (SMPS) and humidified tandem differential mobility analyzer (HTDMA) data
Data imputation in in situ-measured particle size distributions by means of neural networks
Analysis of mobile monitoring data from the microAeth® MA200 for measuring changes in black carbon on the roadside in Augsburg
Estimating mean molecular weight, carbon number, and OM∕OC with mid-infrared spectroscopy in organic particulate matter samples from a monitoring network
Modeled source apportionment of black carbon particles coated with a light-scattering shell
Estimation of particulate organic nitrates from thermodenuder–aerosol mass spectrometer measurements in the North China Plain
Aerosol pH indicator and organosulfate detectability from aerosol mass spectrometry measurements
Determination of equivalent black carbon mass concentration from aerosol light absorption using variable mass absorption cross section
Effects of multi-charge on aerosol hygroscopicity measurement by a HTDMA
A new method for long-term source apportionment with time-dependent factor profiles and uncertainty assessment using SoFi Pro: application to 1 year of organic aerosol data
Estimation of pollen counts from light scattering intensity when sampling multiple pollen taxa – establishment of an automated multi-taxa pollen counting estimation system (AME system)
A novel lidar gradient cluster analysis method of nocturnal boundary layer detection during air pollution episodes
Assessment of particle size magnifier inversion methods to obtain the particle size distribution from atmospheric measurements
A global analysis of climate-relevant aerosol properties retrieved from the network of Global Atmosphere Watch (GAW) near-surface observatories
Development of an automatic linear calibration method for high-resolution single-particle mass spectrometry: improved chemical species identification for atmospheric aerosols
A hybrid method for reconstructing the historical evolution of aerosol optical depth from sunshine duration measurements
The influence of the baseline drift on the resulting extinction values of a cavity attenuated phase shift-based extinction monitor (CAPS PMex)
Zeyuan Tian, Jiandong Wang, Jiaping Wang, Chao Liu, Jia Xing, Jinbo Wang, Zhouyang Zhang, Yuzhi Jin, Sunan Shen, Bin Wang, Wei Nie, Xin Huang, and Aijun Ding
Atmos. Meas. Tech., 18, 1149–1162, https://doi.org/10.5194/amt-18-1149-2025, https://doi.org/10.5194/amt-18-1149-2025, 2025
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The radiative effect of black carbon (BC) is substantially modulated by its mixing state, which is challenging to derive physically with a single-particle soot photometer. This study establishes a machine-learning-based inversion model which can accurately and efficiently acquire the BC mixing state. Compared to the widely used leading-edge-only method, our model utilizes a broader scattering signal coverage to more accurately capture diverse particle characteristics.
Aishah I. Shittu, Kirsty J. Pringle, Stephen R. Arnold, Richard J. Pope, Ailish M. Graham, Carly Reddington, Richard Rigby, and James B. McQuaid
Atmos. Meas. Tech., 18, 817–828, https://doi.org/10.5194/amt-18-817-2025, https://doi.org/10.5194/amt-18-817-2025, 2025
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The study highlighted the performance of Atmotube PRO sensor particulate matter (PM) data. The result showed inter-sensor variability among the Atmotube PRO sensor data. This study showed 62.5 % of the sensors used for the study exhibited greater precision in their PM2.5 measurements. The overall performance showed that sensors passed the base testing using 1 h averaged data and that a multiple linear regression model using relative humidity values improved the performance of the PM2.5 data.
Farhan R. Nursanto, Douglas A. Day, Roy Meinen, Rupert Holzinger, Harald Saathoff, Jinglan Fu, Jan Mulder, Ulrike Dusek, and Juliane L. Fry
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-191, https://doi.org/10.5194/amt-2024-191, 2025
Revised manuscript accepted for AMT
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It is of increasing importance to monitor nitrate pollution that can harm ecosystems. However, commonly used aerosol monitoring equipment cannot distinguish inorganic from organic forms of nitrate, which may have different consequences for the environment. We describe a method to differentiate types of nitrates that can be applied to ambient monitoring to improve understanding of its formation and impact.
Jillian Psotka, Emily Tracey, and Robert Sica
EGUsphere, https://doi.org/10.5194/egusphere-2024-3618, https://doi.org/10.5194/egusphere-2024-3618, 2024
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PurpleAir sensors provide a low-cost way to monitor air quality, with over 30,000 sensors available worldwide. However, their measurements require calibration with trusted data for accuracy. Our new technique builds on previous calibration methods by also enabling the measurement of a quantity related to how pollutants grow with humidity. Mapping this new quantity will improve air quality forecasting.
Rósín Byrne, John C. Wenger, and Stig Hellebust
Atmos. Meas. Tech., 17, 5129–5146, https://doi.org/10.5194/amt-17-5129-2024, https://doi.org/10.5194/amt-17-5129-2024, 2024
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This study presents the concentration similarity index (CSI) for a quantitative and robust comparison of PM2.5 measurements within air quality sensor networks. Developed and tested on two Irish sensor networks, the CSI revealed real spatial variations in PM2.5 and enables assessment of the representativeness of regulatory monitoring locations. It underscores the impact of solid fuel combustion on PM2.5 and highlights the importance of wintertime data for accurate exposure assessments.
Anton Rusanen, Anton Björklund, Manousos I. Manousakas, Jianhui Jiang, Markku T. Kulmala, Kai Puolamäki, and Kaspar R. Daellenbach
Atmos. Meas. Tech., 17, 1251–1277, https://doi.org/10.5194/amt-17-1251-2024, https://doi.org/10.5194/amt-17-1251-2024, 2024
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We present a Bayesian non-negative matrix factorization model that performs better on our test datasets than currently widely used models. Its advantages are better use of time information and providing a direct error estimation. We believe this could lead to better estimates of emission sources from measurements.
Milan Y. Patel, Pietro F. Vannucci, Jinsol Kim, William M. Berelson, and Ronald C. Cohen
Atmos. Meas. Tech., 17, 1051–1060, https://doi.org/10.5194/amt-17-1051-2024, https://doi.org/10.5194/amt-17-1051-2024, 2024
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Low-cost particulate matter (PM) sensors are becoming increasingly common in community monitoring and atmospheric research, but these sensors require proper calibration to provide accurate reporting. Here, we propose a hygroscopic growth calibration scheme that evolves in time to account for seasonal changes in hygroscopic growth. In San Francisco and Los Angeles, CA, applying a seasonal hygroscopic growth calibration can account for sensor biases driven by the seasonal cycles in PM composition.
Xinlei Ge, Yele Sun, Justin Trousdell, Mindong Chen, and Qi Zhang
Atmos. Meas. Tech., 17, 423–439, https://doi.org/10.5194/amt-17-423-2024, https://doi.org/10.5194/amt-17-423-2024, 2024
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This study aims to enhance the application of the Aerodyne high-resolution aerosol mass spectrometer (HR-AMS) in characterizing organic nitrogen (ON) species within aerosol particles and droplets. A thorough analysis was conducted on 75 ON standards that represent a diverse spectrum of ambient ON types. The results underscore the capacity of the HR-AMS in examining the concentration and chemistry of atmospheric ON compounds, thereby offering insights into their sources and environmental impacts.
Guanzhong Wang, Heinrich Ruser, Julian Schade, Johannes Passig, Thomas Adam, Günther Dollinger, and Ralf Zimmermann
Atmos. Meas. Tech., 17, 299–313, https://doi.org/10.5194/amt-17-299-2024, https://doi.org/10.5194/amt-17-299-2024, 2024
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This research aims to develop a novel warning system for the real-time monitoring of pollutants in the atmosphere. The system is capable of sampling and investigating airborne aerosol particles on-site, utilizing artificial intelligence to learn their chemical signatures and to classify them in real time. We applied single-particle mass spectrometry for analyzing the chemical composition of aerosol particles and suggest several supervised algorithms for highly reliable automatic classification.
Sohyeon Jeon, Michael J. Walker, Donna T. Sueper, Douglas A. Day, Anne V. Handschy, Jose L. Jimenez, and Brent J. Williams
Atmos. Meas. Tech., 16, 6075–6095, https://doi.org/10.5194/amt-16-6075-2023, https://doi.org/10.5194/amt-16-6075-2023, 2023
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A searchable database tool for the Aerosol Mass Spectrometer (AMS) and Aerosol Chemical Speciation Monitor (ACSM) mass spectral datasets was built to improve the efficiency of data analysis using Igor Pro. The tool incorporates the published mass spectra (MS) and sample information uploaded on the website. The tool allows users to compare their own mass spectrum with the reference MS in the database.
Jia Liu, Guangya Wang, Cancan Zhu, Donghui Zhou, and Lin Wang
Atmos. Meas. Tech., 16, 4961–4974, https://doi.org/10.5194/amt-16-4961-2023, https://doi.org/10.5194/amt-16-4961-2023, 2023
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Single-particle soot photometer (SP2) employs the core-shell model to represent coated BC particles, which introduces retrieval errors in the mixing state (Dp/Dc) of BC. We construct fractal models to represent thinly and thickly coated BC particles, and the retrieval errors of the mixing state are investigated from the numerical aspect. We find that errors in Dp/Dc are noteworthy, and the errors in Dp/Dc can further affect the evaluation accuracy of the radiative forcing of BC.
Lena Francesca Weissert, Geoff Steven Henshaw, David Edward Williams, Brandon Feenstra, Randy Lam, Ashley Collier-Oxandale, Vasileios Papapostolou, and Andrea Polidori
Atmos. Meas. Tech., 16, 4709–4722, https://doi.org/10.5194/amt-16-4709-2023, https://doi.org/10.5194/amt-16-4709-2023, 2023
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We apply a previously developed remote calibration framework to a network of particulate matter (PM) sensors deployed in Southern California. Our results show that a remote calibration can improve the accuracy of PM data, which was particularly visible for PM10. We highlight that sensor drift was mostly due to differences in particle composition than monitor operational factors. Thus, PM sensors may require frequent calibration if PM sources vary with different wind conditions or seasons.
Weixing Hao, Fan Mei, Susanne Hering, Steven Spielman, Beat Schmid, Jason Tomlinson, and Yang Wang
Atmos. Meas. Tech., 16, 3973–3986, https://doi.org/10.5194/amt-16-3973-2023, https://doi.org/10.5194/amt-16-3973-2023, 2023
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Airborne aerosol instrumentation plays a crucial role in understanding the spatial distribution of ambient aerosol particles. This study investigates a versatile water-based condensation particle counter through simulations and experiments. It provides valuable insights to improve versatile water-based condensation particle counter (vWCPC) aerosol measurement and operation for the community.
Christina N. Vasilakopoulou, Kalliopi Florou, Christos Kaltsonoudis, Iasonas Stavroulas, Nikolaos Mihalopoulos, and Spyros N. Pandis
Atmos. Meas. Tech., 16, 2837–2850, https://doi.org/10.5194/amt-16-2837-2023, https://doi.org/10.5194/amt-16-2837-2023, 2023
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The offline aerosol mass spectrometry technique is a useful tool for the source apportionment of organic aerosol in areas and periods during which an aerosol mass spectrometer is not available. In this work, an improved offline technique was developed and evaluated in an effort to capture most of the partially soluble and insoluble organic aerosol material, reducing the uncertainty of the corresponding source apportionment significantly.
Anton Rusanen, Kristo Hõrrak, Lauri R. Ahonen, Tuomo Nieminen, Pasi P. Aalto, Pasi Kolari, Markku Kulmala, Tuukka Petäjä, and Heikki Junninen
Atmos. Meas. Tech., 16, 2781–2793, https://doi.org/10.5194/amt-16-2781-2023, https://doi.org/10.5194/amt-16-2781-2023, 2023
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We present a framework for setting up SMEAR (Station for Measuring Ecosystem–Atmosphere Relations) type measurement station data flows. This framework, called SMEARcore, consists of modular open-source software components that can be chosen to suit various station configurations. The benefits of using this framework are automation of routine operations and real-time monitoring of measurement results.
Najin Kim, Hang Su, Nan Ma, Ulrich Pöschl, and Yafang Cheng
Atmos. Meas. Tech., 16, 2771–2780, https://doi.org/10.5194/amt-16-2771-2023, https://doi.org/10.5194/amt-16-2771-2023, 2023
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We propose a multiple-charging correction algorithm for a broad-supersaturation scanning cloud condensation nuclei (BS2-CCN) system which can obtain high time-resolution aerosol hygroscopicity and CCN activity. The correction algorithm aims at deriving the activation fraction's true value for each particle size. The meaningful differences between corrected and original κ values (single hygroscopicity parameter) emphasize the correction algorithm's importance for ambient aerosol measurement.
Daniel A. Jaffe, Colleen Miller, Katie Thompson, Brandon Finley, Manna Nelson, James Ouimette, and Elisabeth Andrews
Atmos. Meas. Tech., 16, 1311–1322, https://doi.org/10.5194/amt-16-1311-2023, https://doi.org/10.5194/amt-16-1311-2023, 2023
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PurpleAir sensors (PASs) are low-cost tools to measure fine particulate matter (PM) concentrations. However, the raw PAS data have significant biases, so the sensors must be corrected. We analyzed data from numerous sites and found that the standard correction to the PAS Purple Air data is accurate in urban pollution events and smoke events but leads to a 6-fold underestimate in the PM2.5 concentrations in dust events. We propose a new correction algorithm to address this problem.
Yilin Chen, Yuanjian Yang, and Meng Gao
Atmos. Meas. Tech., 16, 1279–1294, https://doi.org/10.5194/amt-16-1279-2023, https://doi.org/10.5194/amt-16-1279-2023, 2023
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The Guangdong–Hong Kong–Macao Greater Bay Area suffers from summertime air pollution events related to typhoons. The present study leverages machine learning to predict typhoon-associated air quality over the area. The model evaluation shows that the model performs excellently. Moreover, the change in meteorological drivers of air quality on typhoon days and non-typhoon days suggests that air pollution control strategies should have different focuses on typhoon days and non-typhoon days.
Yandong Tong, Lu Qi, Giulia Stefenelli, Dongyu Simon Wang, Francesco Canonaco, Urs Baltensperger, André Stephan Henry Prévôt, and Jay Gates Slowik
Atmos. Meas. Tech., 15, 7265–7291, https://doi.org/10.5194/amt-15-7265-2022, https://doi.org/10.5194/amt-15-7265-2022, 2022
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We present a method for positive matrix factorisation (PMF) analysis on a single dataset that includes measurements from both EESI-TOF and AMS in Zurich, Switzerland. For the first time, we resolved and quantified secondary organic aerosol (SOA) sources. Meanwhile, we also determined the retrieved EESI-TOF factor-dependent sensitivities. This method provides a framework for exploiting semi-quantitative, high-resolution instrumentation for quantitative source apportionment.
Zefeng Zhang, Hengnan Guo, Hanqing Kang, Jing Wang, Junlin An, Xingna Yu, Jingjing Lv, and Bin Zhu
Atmos. Meas. Tech., 15, 7259–7264, https://doi.org/10.5194/amt-15-7259-2022, https://doi.org/10.5194/amt-15-7259-2022, 2022
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In this study, we first analyze the relationship between the visibility, the extinction coefficient, and atmospheric compositions. Then we propose to use the harmonic average of visibility data as the average visibility, which can better reflect changes in atmospheric extinction coefficients and aerosol concentrations. It is recommended to use the harmonic average visibility in the studies of climate change, atmospheric radiation, air pollution, environmental health, etc.
Hyungwon John Park, Jeffrey S. Reid, Livia S. Freire, Christopher Jackson, and David H. Richter
Atmos. Meas. Tech., 15, 7171–7194, https://doi.org/10.5194/amt-15-7171-2022, https://doi.org/10.5194/amt-15-7171-2022, 2022
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We use numerical models to study field measurements of sea spray aerosol particles and conclude that both the atmospheric state and the methods of instrument sampling are causes for the variation in the production rate of aerosol particles: a critical metric to learn the aerosol's effect on processes like cloud physics and radiation. This work helps field observers improve their experimental design and interpretation of measurements because of turbulence in the atmosphere.
Christina Vasilakopoulou, Iasonas Stavroulas, Nikolaos Mihalopoulos, and Spyros N. Pandis
Atmos. Meas. Tech., 15, 6419–6431, https://doi.org/10.5194/amt-15-6419-2022, https://doi.org/10.5194/amt-15-6419-2022, 2022
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Offline aerosol mass spectrometer (AMS) measurements can provide valuable information about ambient organic aerosols when online AMS measurements are not available. In this study, we examine whether and how the low time resolution (usually 24 h) of the offline technique affects source apportionment results. We concluded that use of the daily averages resulted in estimated average contributions that were within 8 % of the total OA compared with the high-resolution analysis.
Priyanka deSouza, Ralph Kahn, Tehya Stockman, William Obermann, Ben Crawford, An Wang, James Crooks, Jing Li, and Patrick Kinney
Atmos. Meas. Tech., 15, 6309–6328, https://doi.org/10.5194/amt-15-6309-2022, https://doi.org/10.5194/amt-15-6309-2022, 2022
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How sensitive are the spatial and temporal trends of PM2.5 derived from a network of low-cost sensors to the calibration adjustment used? How transferable are calibration equations developed at a few co-location sites to an entire network of low-cost sensors? This paper attempts to answer this question and offers a series of suggestions on how to develop the most robust calibration function for different end uses. It uses measurements from the Love My Air network in Denver as a test case.
Sahil Bhandari, Zainab Arub, Gazala Habib, Joshua S. Apte, and Lea Hildebrandt Ruiz
Atmos. Meas. Tech., 15, 6051–6074, https://doi.org/10.5194/amt-15-6051-2022, https://doi.org/10.5194/amt-15-6051-2022, 2022
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We present a new method to conduct source apportionment resolved by time of day using the underlying approach of positive matrix factorization. We report results for four example time periods in two seasons (winter and monsoon 2017) in Delhi, India. Compared to the traditional approach, we extract a larger number of factors that represent the expected sources of primary organic aerosol. This method can capture diurnal time series patterns of sources at low computational cost.
Alireza Moallemi, Rob L. Modini, Tatyana Lapyonok, Anton Lopatin, David Fuertes, Oleg Dubovik, Philippe Giaccari, and Martin Gysel-Beer
Atmos. Meas. Tech., 15, 5619–5642, https://doi.org/10.5194/amt-15-5619-2022, https://doi.org/10.5194/amt-15-5619-2022, 2022
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Aerosol properties (size distributions, refractive indices) can be retrieved from in situ, angularly resolved light scattering measurements performed with polar nephelometers. We apply an established framework to assess the aerosol property retrieval potential for different instrument configurations, target applications, and assumed prior knowledge. We also demonstrate how a reductive greedy algorithm can be used to determine the optimal placements of the angular sensors in a polar nephelometer.
Marta Via, Gang Chen, Francesco Canonaco, Kaspar R. Daellenbach, Benjamin Chazeau, Hasna Chebaicheb, Jianhui Jiang, Hannes Keernik, Chunshui Lin, Nicolas Marchand, Cristina Marin, Colin O'Dowd, Jurgita Ovadnevaite, Jean-Eudes Petit, Michael Pikridas, Véronique Riffault, Jean Sciare, Jay G. Slowik, Leïla Simon, Jeni Vasilescu, Yunjiang Zhang, Olivier Favez, André S. H. Prévôt, Andrés Alastuey, and María Cruz Minguillón
Atmos. Meas. Tech., 15, 5479–5495, https://doi.org/10.5194/amt-15-5479-2022, https://doi.org/10.5194/amt-15-5479-2022, 2022
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This work presents the differences resulting from two techniques (rolling and seasonal) of the positive matrix factorisation model that can be run for organic aerosol source apportionment. The current state of the art suggests that the rolling technique is more accurate, but no proof of its effectiveness has been provided yet. This paper tackles this issue in the context of a synthetic dataset and a multi-site real-world comparison.
Sungwoo Kim, Brian M. Lerner, Donna T. Sueper, and Gabriel Isaacman-VanWertz
Atmos. Meas. Tech., 15, 5061–5075, https://doi.org/10.5194/amt-15-5061-2022, https://doi.org/10.5194/amt-15-5061-2022, 2022
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Atmospheric samples can be complex, and current analysis methods often require substantial human interaction and discard potentially important information. To improve analysis accuracy and computational cost of these large datasets, we developed an automated analysis algorithm that utilizes a factor analysis approach coupled with a decision tree. We demonstrate that this algorithm cataloged approximately 10 times more analytes compared to a manual analysis and in a quarter of the analysis time.
Olga Zografou, Maria Gini, Manousos I. Manousakas, Gang Chen, Athina C. Kalogridis, Evangelia Diapouli, Athina Pappa, and Konstantinos Eleftheriadis
Atmos. Meas. Tech., 15, 4675–4692, https://doi.org/10.5194/amt-15-4675-2022, https://doi.org/10.5194/amt-15-4675-2022, 2022
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A yearlong ToF-ACSM dataset was used to characterize ambient aerosols over a suburban Athenian site, and innovative software for source apportionment was implemented in order to distinguish the sources of the total non-refractory species of PM1. A comparison between the methodology of combined organic and inorganic PMF analysis and the conventional organic PMF took place.
Jeramy L. Dedrick, Georges Saliba, Abigail S. Williams, Lynn M. Russell, and Dan Lubin
Atmos. Meas. Tech., 15, 4171–4194, https://doi.org/10.5194/amt-15-4171-2022, https://doi.org/10.5194/amt-15-4171-2022, 2022
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A new method is presented to retrieve the sea spray aerosol size distribution by combining submicron size and nephelometer scattering based on Mie theory. Using available sea spray tracers, we find that this approach serves as a comparable substitute to supermicron size distribution measurements, which are limited in availability at marine sites. Application of this technique can expand sea spray observations and improve the characterization of marine aerosol impacts on clouds and climate.
Ivo Beck, Hélène Angot, Andrea Baccarini, Lubna Dada, Lauriane Quéléver, Tuija Jokinen, Tiia Laurila, Markus Lampimäki, Nicolas Bukowiecki, Matthew Boyer, Xianda Gong, Martin Gysel-Beer, Tuukka Petäjä, Jian Wang, and Julia Schmale
Atmos. Meas. Tech., 15, 4195–4224, https://doi.org/10.5194/amt-15-4195-2022, https://doi.org/10.5194/amt-15-4195-2022, 2022
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We present the pollution detection algorithm (PDA), a new method to identify local primary pollution in remote atmospheric aerosol and trace gas time series. The PDA identifies periods of contaminated data and relies only on the target dataset itself; i.e., it is independent of ancillary data such as meteorological variables. The parameters of all pollution identification steps are adjustable so that the PDA can be tuned to different locations and situations. It is available as open-access code.
Emily B. Franklin, Lindsay D. Yee, Bernard Aumont, Robert J. Weber, Paul Grigas, and Allen H. Goldstein
Atmos. Meas. Tech., 15, 3779–3803, https://doi.org/10.5194/amt-15-3779-2022, https://doi.org/10.5194/amt-15-3779-2022, 2022
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The composition of atmospheric aerosols are extremely complex, containing hundreds of thousands of estimated individual compounds. The majority of these compounds have never been catalogued in widely used databases, making them extremely difficult for atmospheric chemists to identify and analyze. In this work, we present Ch3MS-RF, a machine-learning-based model to enable characterization of complex mixtures and prediction of structure-specific properties of unidentifiable organic compounds.
Jiaoshi Zhang, Yang Wang, Steven Spielman, Susanne Hering, and Jian Wang
Atmos. Meas. Tech., 15, 2579–2590, https://doi.org/10.5194/amt-15-2579-2022, https://doi.org/10.5194/amt-15-2579-2022, 2022
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New nonparametric, regularized methods are developed to invert the growth factor probability density function (GF-PDF) from humidity-controlled fast integrated mobility spectrometer measurements. These algorithms are computationally efficient, require no prior assumptions of the GF-PDF distribution, and reduce the error in inverted GF-PDF. They can be applied to humidified tandem differential mobility analyzer data. Among all algorithms, Twomey’s method retrieves GF-PDF with the smallest error.
Douglas A. Day, Pedro Campuzano-Jost, Benjamin A. Nault, Brett B. Palm, Weiwei Hu, Hongyu Guo, Paul J. Wooldridge, Ronald C. Cohen, Kenneth S. Docherty, J. Alex Huffman, Suzane S. de Sá, Scot T. Martin, and Jose L. Jimenez
Atmos. Meas. Tech., 15, 459–483, https://doi.org/10.5194/amt-15-459-2022, https://doi.org/10.5194/amt-15-459-2022, 2022
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Particle-phase nitrates are an important component of atmospheric aerosols and chemistry. In this paper, we systematically explore the application of aerosol mass spectrometry (AMS) to quantify the organic and inorganic nitrate fractions of aerosols in the atmosphere. While AMS has been used for a decade to quantify nitrates, methods are not standardized. We make recommendations for a more universal approach based on this analysis of a large range of field and laboratory observations.
Markus D. Petters
Atmos. Meas. Tech., 14, 7909–7928, https://doi.org/10.5194/amt-14-7909-2021, https://doi.org/10.5194/amt-14-7909-2021, 2021
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Inverse methods infer physical properties from a measured instrument response. Measurement noise often interferes with the inversion. This work presents a general, domain-independent, accessible, and computationally efficient software implementation of a common class of statistical inversion methods. In addition, a new method to invert data from humidified tandem differential mobility analyzers is introduced. Results show that the approach is suitable for inversion of large-scale datasets.
Pak Lun Fung, Martha Arbayani Zaidan, Ola Surakhi, Sasu Tarkoma, Tuukka Petäjä, and Tareq Hussein
Atmos. Meas. Tech., 14, 5535–5554, https://doi.org/10.5194/amt-14-5535-2021, https://doi.org/10.5194/amt-14-5535-2021, 2021
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Aerosol size distribution measurements rely on a variety of techniques to classify the aerosol size and measure the size distribution. However, due to the instrumental insufficiency and inversion limitations, the raw dataset contains missing gaps or negative values, which hinder further analysis. With a merged particle size distribution in Jordan, this paper suggests a neural network method to estimate number concentrations at a particular size bin by the number concentration at other size bins.
Xiansheng Liu, Hadiatullah Hadiatullah, Xun Zhang, L. Drew Hill, Andrew H. A. White, Jürgen Schnelle-Kreis, Jan Bendl, Gert Jakobi, Brigitte Schloter-Hai, and Ralf Zimmermann
Atmos. Meas. Tech., 14, 5139–5151, https://doi.org/10.5194/amt-14-5139-2021, https://doi.org/10.5194/amt-14-5139-2021, 2021
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A monitoring campaign was conducted in Augsburg to determine a suitable noise reduction algorithm for the MA200 Aethalometer. Results showed that centred moving average (CMA) post-processing effectively removed spurious negative concentrations without major bias and reliably highlighted effects from local sources, effectively increasing spatio-temporal resolution in mobile measurements. Evaluation of each method on peak sample reduction and background correction further supports the reliability.
Amir Yazdani, Ann M. Dillner, and Satoshi Takahama
Atmos. Meas. Tech., 14, 4805–4827, https://doi.org/10.5194/amt-14-4805-2021, https://doi.org/10.5194/amt-14-4805-2021, 2021
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We propose a spectroscopic method for estimating several mixture-averaged molecular properties (carbon number and molecular weight) in particulate matter relevant for understanding its chemical origins. This estimation is enabled by calibration models built and tested using laboratory standards containing molecules with known structure, and can be applied to filter samples of PM2.5 currently collected in existing air pollution monitoring networks and field campaigns.
Aki Virkkula
Atmos. Meas. Tech., 14, 3707–3719, https://doi.org/10.5194/amt-14-3707-2021, https://doi.org/10.5194/amt-14-3707-2021, 2021
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The Aethalometer model is used widely for estimating the contributions of fossil fuel emissions and biomass burning to black carbon. The calculation is based on measured absorption Ångström exponents, which is ambiguous since it not only depends on the dominant absorber but also on the size and internal structure of the particles, core size, and shell thickness. The uncertainties of the fractions of absorption by eBC from fossil fuel and biomass burning are evaluated with a core–shell Mie model.
Weiqi Xu, Masayuki Takeuchi, Chun Chen, Yanmei Qiu, Conghui Xie, Wanyun Xu, Nan Ma, Douglas R. Worsnop, Nga Lee Ng, and Yele Sun
Atmos. Meas. Tech., 14, 3693–3705, https://doi.org/10.5194/amt-14-3693-2021, https://doi.org/10.5194/amt-14-3693-2021, 2021
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Here we developed a method for estimation of particulate organic nitrates (pON) from the measurements of a high-resolution aerosol mass spectrometer coupled with a thermodenuder based on the volatility differences between inorganic nitrate and pON. The results generally had improvements in reducing negative values due to the influences of a high concentration of inorganic nitrate and a constant ratio of NO+ to NO2+ of organic nitrates (RON).
Melinda K. Schueneman, Benjamin A. Nault, Pedro Campuzano-Jost, Duseong S. Jo, Douglas A. Day, Jason C. Schroder, Brett B. Palm, Alma Hodzic, Jack E. Dibb, and Jose L. Jimenez
Atmos. Meas. Tech., 14, 2237–2260, https://doi.org/10.5194/amt-14-2237-2021, https://doi.org/10.5194/amt-14-2237-2021, 2021
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This work focuses on two important properties of the aerosol, acidity, and sulfate composition, which is important for our understanding of aerosol health and environmental impacts. We explore different methods to understand the composition of the aerosol with measurements from a specific instrument and apply those methods to a large dataset. These measurements are confounded by other factors, making it challenging to predict aerosol sulfate composition; pH estimations, however, show promise.
Weilun Zhao, Wangshu Tan, Gang Zhao, Chuanyang Shen, Yingli Yu, and Chunsheng Zhao
Atmos. Meas. Tech., 14, 1319–1331, https://doi.org/10.5194/amt-14-1319-2021, https://doi.org/10.5194/amt-14-1319-2021, 2021
Chuanyang Shen, Gang Zhao, and Chunsheng Zhao
Atmos. Meas. Tech., 14, 1293–1301, https://doi.org/10.5194/amt-14-1293-2021, https://doi.org/10.5194/amt-14-1293-2021, 2021
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Aerosol hygroscopicity measured by the humidified tandem differential mobility analyzer (HTDMA) is affected by multiply charged particles from two aspects: (1) number contribution and (2) the weakening effect. An algorithm is proposed to do the multi-charge correction and applied to a field measurement. Results show that the difference between corrected and measured size-resolved κ can reach 0.05, highlighting that special attention needs to be paid to the multi-charge effect when using HTDMA.
Francesco Canonaco, Anna Tobler, Gang Chen, Yulia Sosedova, Jay Gates Slowik, Carlo Bozzetti, Kaspar Rudolf Daellenbach, Imad El Haddad, Monica Crippa, Ru-Jin Huang, Markus Furger, Urs Baltensperger, and André Stephan Henry Prévôt
Atmos. Meas. Tech., 14, 923–943, https://doi.org/10.5194/amt-14-923-2021, https://doi.org/10.5194/amt-14-923-2021, 2021
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Long-term ambient aerosol mass spectrometric data were analyzed with a statistical model (PMF) to obtain source contributions and fingerprints. The new aspects of this paper involve time-dependent source fingerprints by a rolling technique and the replacement of the full visual inspection of each run by a user-defined set of criteria to monitor the quality of each of these runs more efficiently. More reliable sources will finally provide better instruments for political mitigation strategies.
Kenji Miki and Shigeto Kawashima
Atmos. Meas. Tech., 14, 685–693, https://doi.org/10.5194/amt-14-685-2021, https://doi.org/10.5194/amt-14-685-2021, 2021
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Laser optics have long been used in pollen counting systems. To clarify the limitations and potential new applications of laser optics for automatic pollen counting and discrimination, we determined the light scattering patterns of various pollen types, tracked temporal changes in these distributions, and introduced a new theory for automatic pollen discrimination.
Yinchao Zhang, Su Chen, Siying Chen, He Chen, and Pan Guo
Atmos. Meas. Tech., 13, 6675–6689, https://doi.org/10.5194/amt-13-6675-2020, https://doi.org/10.5194/amt-13-6675-2020, 2020
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Air pollution has an important impact on human health, climatic patterns, and the ecological environment. The complexity of the nocturnal boundary layer (NBL), combined with its strong physio-chemical effect, induces worse polluted episodes. Therefore, we present a new approach named cluster analysis of gradient method (CA-GM) to overcome the multilayer structure and remove the fluctuation of NBL height using raw data resolution.
Tommy Chan, Runlong Cai, Lauri R. Ahonen, Yiliang Liu, Ying Zhou, Joonas Vanhanen, Lubna Dada, Yan Chao, Yongchun Liu, Lin Wang, Markku Kulmala, and Juha Kangasluoma
Atmos. Meas. Tech., 13, 4885–4898, https://doi.org/10.5194/amt-13-4885-2020, https://doi.org/10.5194/amt-13-4885-2020, 2020
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Using a particle size magnifier (PSM; Airmodus, Finland), we determined the particle size distribution using four inversion methods and compared each method to the others to establish their strengths and weaknesses. Furthermore, we provided a step-by-step procedure on how to invert measured data using the PSM. Finally, we provided recommendations, code and data related to the data inversion. This is an important paper, as no operating procedure exists regarding how to process measured PSM data.
Paolo Laj, Alessandro Bigi, Clémence Rose, Elisabeth Andrews, Cathrine Lund Myhre, Martine Collaud Coen, Yong Lin, Alfred Wiedensohler, Michael Schulz, John A. Ogren, Markus Fiebig, Jonas Gliß, Augustin Mortier, Marco Pandolfi, Tuukka Petäja, Sang-Woo Kim, Wenche Aas, Jean-Philippe Putaud, Olga Mayol-Bracero, Melita Keywood, Lorenzo Labrador, Pasi Aalto, Erik Ahlberg, Lucas Alados Arboledas, Andrés Alastuey, Marcos Andrade, Begoña Artíñano, Stina Ausmeel, Todor Arsov, Eija Asmi, John Backman, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Sébastien Conil, Cedric Couret, Derek Day, Wan Dayantolis, Anna Degorska, Konstantinos Eleftheriadis, Prodromos Fetfatzis, Olivier Favez, Harald Flentje, Maria I. Gini, Asta Gregorič, Martin Gysel-Beer, A. Gannet Hallar, Jenny Hand, Andras Hoffer, Christoph Hueglin, Rakesh K. Hooda, Antti Hyvärinen, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Jeong Eun Kim, Giorgos Kouvarakis, Irena Kranjc, Radovan Krejci, Markku Kulmala, Casper Labuschagne, Hae-Jung Lee, Heikki Lihavainen, Neng-Huei Lin, Gunter Löschau, Krista Luoma, Angela Marinoni, Sebastiao Martins Dos Santos, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Nhat Anh Nguyen, Jakub Ondracek, Noemi Pérez, Maria Rita Perrone, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Natalia Prats, Anthony Prenni, Fabienne Reisen, Salvatore Romano, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Maik Schütze, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Martin Steinbacher, Junying Sun, Gloria Titos, Barbara Toczko, Thomas Tuch, Pierre Tulet, Peter Tunved, Ville Vakkari, Fernando Velarde, Patricio Velasquez, Paolo Villani, Sterios Vratolis, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Jesus Yus-Diez, Vladimir Zdimal, Paul Zieger, and Nadezda Zikova
Atmos. Meas. Tech., 13, 4353–4392, https://doi.org/10.5194/amt-13-4353-2020, https://doi.org/10.5194/amt-13-4353-2020, 2020
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The paper establishes the fiducial reference of the GAW aerosol network providing the fully characterized value chain to the provision of four climate-relevant aerosol properties from ground-based sites. Data from almost 90 stations worldwide are reported for a reference year, 2017, providing a unique and very robust view of the variability of these variables worldwide. Current gaps in the GAW network are analysed and requirements for the Global Climate Monitoring System are proposed.
Shengqiang Zhu, Lei Li, Shurong Wang, Mei Li, Yaxi Liu, Xiaohui Lu, Hong Chen, Lin Wang, Jianmin Chen, Zhen Zhou, Xin Yang, and Xiaofei Wang
Atmos. Meas. Tech., 13, 4111–4121, https://doi.org/10.5194/amt-13-4111-2020, https://doi.org/10.5194/amt-13-4111-2020, 2020
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Single-particle aerosol mass spectrometry (SPAMS) is widely used to detect chemical compositions and sizes of individual aerosol particles. However, it has a major issue: the mass accuracy of high-resolution SPAMS is relatively low. Here we developed an automatic linear calibration method to greatly improve the mass accuracy of SPAMS spectra so that the elemental compositions of organic peaks, such as Cx, CxHy, CxHyOz and CxHyNO peaks, can be directly identified just based on their m / z values.
William Wandji Nyamsi, Antti Lipponen, Arturo Sanchez-Lorenzo, Martin Wild, and Antti Arola
Atmos. Meas. Tech., 13, 3061–3079, https://doi.org/10.5194/amt-13-3061-2020, https://doi.org/10.5194/amt-13-3061-2020, 2020
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This paper proposes a novel and accurate method for estimating and reconstructing aerosol optical depth from sunshine duration measurements under cloud-free conditions at any place and time since the late 19th century. The method performs very well when compared to AErosol RObotic NETwork measurements and operates an efficient detection of signals from massive volcanic eruptions. Reconstructed long-term aerosol optical depths are in agreement with the dimming/brightening phenomenon.
Sascha Pfeifer, Thomas Müller, Andrew Freedman, and Alfred Wiedensohler
Atmos. Meas. Tech., 13, 2161–2167, https://doi.org/10.5194/amt-13-2161-2020, https://doi.org/10.5194/amt-13-2161-2020, 2020
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The effect of the baseline drift on the resulting extinction values of three CAPS PMex monitors with different wavelengths was analysed for an urban background station. A significant baseline drift was observed, which leads to characteristic measurement artefacts for particle extinction. Two alternative methods for recalculating the baseline are shown. With these methods the extinction artefacts are diminished and the effective scattering of the resulting extinction values is reduced.
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Short summary
Considering nephelometers' major problems of a nonideal Lambertian light source and angle truncation, a new correction method based on a machine learning model is proposed. Our method has the advantage of obtaining data with high accuracy while achieving self-correction, which means that researchers can get more accurate scattering coefficients without the need for additional observation data. This method provides a more precise estimation of the aerosol’s direct radiative forcing.
Considering nephelometers' major problems of a nonideal Lambertian light source and angle...
