Articles | Volume 20, issue 11
https://doi.org/10.5194/acp-20-6953-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-20-6953-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 Jun 2020
Research article |
| 12 Jun 2020
| 12 Jun 2020
Air mass physiochemical characteristics over New Delhi: impacts on aerosol hygroscopicity and cloud condensation nuclei (CCN) formation
Department of Civil Engineering, Indian Institute of Technology
Delhi, New Delhi, India
Sahil Bhandari
McKetta Department of Chemical Engineering, The University of Texas
at Austin, Austin, Texas, USA
Shahzad Gani
Department of Civil, Architectural and Environmental Engineering, The
University of Texas at Austin, Austin, Texas, USA
Joshua S. Apte
Department of Civil, Architectural and Environmental Engineering, The
University of Texas at Austin, Austin, Texas, USA
Lea Hildebrandt Ruiz
McKetta Department of Chemical Engineering, The University of Texas
at Austin, Austin, Texas, USA
Gazala Habib
Department of Civil Engineering, Indian Institute of Technology
Delhi, New Delhi, India
Related authors
Sahil Bhandari, Zainab Arub, Gazala Habib, Joshua S. Apte, and Lea Hildebrandt Ruiz
Atmos. Chem. Phys., 22, 13631–13657, https://doi.org/10.5194/acp-22-13631-2022, https://doi.org/10.5194/acp-22-13631-2022, 2022
Short summary
Short summary
Here we determine the sources of primary organic aerosol in Delhi, India, in two different seasons. In winter, the main sources are traffic and biomass burning; in the summer, the main sources are traffic and cooking. We obtain this result by conducting source apportionment resolved by time of day, using data from an aerosol chemical speciation monitor. Results from this work can be used to better design policies that target sources of organic aerosol.
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
Short summary
Short summary
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.
Shahzad Gani, Louise Arnal, Lucy Beattie, John Hillier, Sam Illingworth, Tiziana Lanza, Solmaz Mohadjer, Karoliina Pulkkinen, Heidi Roop, Iain Stewart, Kirsten von Elverfeldt, and Stephanie Zihms
Geosci. Commun., 7, 251–266, https://doi.org/10.5194/gc-7-251-2024, https://doi.org/10.5194/gc-7-251-2024, 2024
Short summary
Short summary
Science communication in geosciences has societal and scientific value but often operates in “shadowlands”. This editorial highlights these issues and proposes potential solutions. Our objective is to create a transparent and responsible geoscience communication landscape, fostering scientific progress, the well-being of scientists, and societal benefits.
Bjorn Stevens, Stefan Adami, Tariq Ali, Hartwig Anzt, Zafer Aslan, Sabine Attinger, Jaana Bäck, Johanna Baehr, Peter Bauer, Natacha Bernier, Bob Bishop, Hendryk Bockelmann, Sandrine Bony, Guy Brasseur, David N. Bresch, Sean Breyer, Gilbert Brunet, Pier Luigi Buttigieg, Junji Cao, Christelle Castet, Yafang Cheng, Ayantika Dey Choudhury, Deborah Coen, Susanne Crewell, Atish Dabholkar, Qing Dai, Francisco Doblas-Reyes, Dale Durran, Ayoub El Gaidi, Charlie Ewen, Eleftheria Exarchou, Veronika Eyring, Florencia Falkinhoff, David Farrell, Piers M. Forster, Ariane Frassoni, Claudia Frauen, Oliver Fuhrer, Shahzad Gani, Edwin Gerber, Debra Goldfarb, Jens Grieger, Nicolas Gruber, Wilco Hazeleger, Rolf Herken, Chris Hewitt, Torsten Hoefler, Huang-Hsiung Hsu, Daniela Jacob, Alexandra Jahn, Christian Jakob, Thomas Jung, Christopher Kadow, In-Sik Kang, Sarah Kang, Karthik Kashinath, Katharina Kleinen-von Königslöw, Daniel Klocke, Uta Kloenne, Milan Klöwer, Chihiro Kodama, Stefan Kollet, Tobias Kölling, Jenni Kontkanen, Steve Kopp, Michal Koran, Markku Kulmala, Hanna Lappalainen, Fakhria Latifi, Bryan Lawrence, June Yi Lee, Quentin Lejeun, Christian Lessig, Chao Li, Thomas Lippert, Jürg Luterbacher, Pekka Manninen, Jochem Marotzke, Satoshi Matsouoka, Charlotte Merchant, Peter Messmer, Gero Michel, Kristel Michielsen, Tomoki Miyakawa, Jens Müller, Ramsha Munir, Sandeep Narayanasetti, Ousmane Ndiaye, Carlos Nobre, Achim Oberg, Riko Oki, Tuba Özkan-Haller, Tim Palmer, Stan Posey, Andreas Prein, Odessa Primus, Mike Pritchard, Julie Pullen, Dian Putrasahan, Johannes Quaas, Krishnan Raghavan, Venkatachalam Ramaswamy, Markus Rapp, Florian Rauser, Markus Reichstein, Aromar Revi, Sonakshi Saluja, Masaki Satoh, Vera Schemann, Sebastian Schemm, Christina Schnadt Poberaj, Thomas Schulthess, Cath Senior, Jagadish Shukla, Manmeet Singh, Julia Slingo, Adam Sobel, Silvina Solman, Jenna Spitzer, Philip Stier, Thomas Stocker, Sarah Strock, Hang Su, Petteri Taalas, John Taylor, Susann Tegtmeier, Georg Teutsch, Adrian Tompkins, Uwe Ulbrich, Pier-Luigi Vidale, Chien-Ming Wu, Hao Xu, Najibullah Zaki, Laure Zanna, Tianjun Zhou, and Florian Ziemen
Earth Syst. Sci. Data, 16, 2113–2122, https://doi.org/10.5194/essd-16-2113-2024, https://doi.org/10.5194/essd-16-2113-2024, 2024
Short summary
Short summary
To manage Earth in the Anthropocene, new tools, new institutions, and new forms of international cooperation will be required. Earth Virtualization Engines is proposed as an international federation of centers of excellence to empower all people to respond to the immense and urgent challenges posed by climate change.
Anil Kumar Mandariya, Ajit Ahlawat, Mohammed Haneef, Nisar Ali Baig, Kanan Patel, Joshua Apte, Lea Hildebrandt Ruiz, Alfred Wiedensohler, and Gazala Habib
Atmos. Chem. Phys., 24, 3627–3647, https://doi.org/10.5194/acp-24-3627-2024, https://doi.org/10.5194/acp-24-3627-2024, 2024
Short summary
Short summary
The current study explores the temporal variation of size-selected particle hygroscopicity in Delhi for the first time. Here, we report that the high volume fraction contribution of ammonium chloride to aerosol governs the high aerosol hygroscopicity and associated liquid water content based on the experimental data. The episodically high ammonium chloride present in Delhi's atmosphere could lead to haze and fog formation under high relative humidity in the region.
Mark Joseph Campmier, Jonathan Gingrich, Saumya Singh, Nisar Baig, Shahzad Gani, Adithi Upadhya, Pratyush Agrawal, Meenakshi Kushwaha, Harsh Raj Mishra, Ajay Pillarisetti, Sreekanth Vakacherla, Ravi Kant Pathak, and Joshua S. Apte
Atmos. Meas. Tech., 16, 4357–4374, https://doi.org/10.5194/amt-16-4357-2023, https://doi.org/10.5194/amt-16-4357-2023, 2023
Short summary
Short summary
We studied a low-cost air pollution sensor called PurpleAir PA-II in three different locations in India (Delhi, Hamirpur, and Bangalore) to characterize its performance. We compared its signal to more expensive reference sensors and found that the PurpleAir sensor was precise but inaccurate without calibration. We created a custom calibration equation for each location, which improved the accuracy of the PurpleAir sensor, and found that calibrations should be adjusted for different seasons.
Sahil Bhandari, Zainab Arub, Gazala Habib, Joshua S. Apte, and Lea Hildebrandt Ruiz
Atmos. Chem. Phys., 22, 13631–13657, https://doi.org/10.5194/acp-22-13631-2022, https://doi.org/10.5194/acp-22-13631-2022, 2022
Short summary
Short summary
Here we determine the sources of primary organic aerosol in Delhi, India, in two different seasons. In winter, the main sources are traffic and biomass burning; in the summer, the main sources are traffic and cooking. We obtain this result by conducting source apportionment resolved by time of day, using data from an aerosol chemical speciation monitor. Results from this work can be used to better design policies that target sources of organic aerosol.
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
Short summary
Short summary
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.
Benjamin Foreback, Lubna Dada, Kaspar R. Daellenbach, Chao Yan, Lili Wang, Biwu Chu, Ying Zhou, Tom V. Kokkonen, Mona Kurppa, Rosaria E. Pileci, Yonghong Wang, Tommy Chan, Juha Kangasluoma, Lin Zhuohui, Yishou Guo, Chang Li, Rima Baalbaki, Joni Kujansuu, Xiaolong Fan, Zemin Feng, Pekka Rantala, Shahzad Gani, Federico Bianchi, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, Yongchun Liu, and Pauli Paasonen
Atmos. Chem. Phys., 22, 11089–11104, https://doi.org/10.5194/acp-22-11089-2022, https://doi.org/10.5194/acp-22-11089-2022, 2022
Short summary
Short summary
This study analyzed air quality in Beijing during the Chinese New Year over 7 years, including data from a new in-depth measurement station. This is one of few studies to look at long-term impacts, including the outcome of firework restrictions starting in 2018. Results show that firework pollution has gone down since 2016, indicating a positive result from the restrictions. Results of this study may be useful in making future decisions about the use of fireworks to improve air quality.
Ying Zhou, Simo Hakala, Chao Yan, Yang Gao, Xiaohong Yao, Biwu Chu, Tommy Chan, Juha Kangasluoma, Shahzad Gani, Jenni Kontkanen, Pauli Paasonen, Yongchun Liu, Tuukka Petäjä, Markku Kulmala, and Lubna Dada
Atmos. Chem. Phys., 21, 17885–17906, https://doi.org/10.5194/acp-21-17885-2021, https://doi.org/10.5194/acp-21-17885-2021, 2021
Short summary
Short summary
We characterized the connection between new particle formation (NPF) events in terms of frequency, intensity and growth at a near-highway location in central Beijing and at a background mountain site 80 km away. Due to the substantial contribution of NPF to the global aerosol budget, identifying the conditions that promote the occurrence of regional NPF events could help understand their contribution on a large scale and would improve their implementation in global models.
Shahzad Gani, Lukas Kohl, Rima Baalbaki, Federico Bianchi, Taina M. Ruuskanen, Olli-Pekka Siira, Pauli Paasonen, and Hanna Vehkamäki
Geosci. Commun., 4, 507–516, https://doi.org/10.5194/gc-4-507-2021, https://doi.org/10.5194/gc-4-507-2021, 2021
Short summary
Short summary
In this article, we present authorship guidelines which also include a novel authorship form along with the documentation of the formulation process for a multidisciplinary and interdisciplinary center with more than 250 researchers. Our practical approach promotes fair authorship practices and, by focusing on clear, transparent, and timely communication, helps avoid late-stage authorship conflict.
Shahzad Gani, Sahil Bhandari, Kanan Patel, Sarah Seraj, Prashant Soni, Zainab Arub, Gazala Habib, Lea Hildebrandt Ruiz, and Joshua S. Apte
Atmos. Chem. Phys., 20, 8533–8549, https://doi.org/10.5194/acp-20-8533-2020, https://doi.org/10.5194/acp-20-8533-2020, 2020
Short summary
Short summary
Delhi, India, has had the highest fine particle mass (PM2.5; diameter < 2.5 µm) concentrations of any megacity on the planet in recent years. Here, we undertook a year of detailed measurements of particle size distributions. We observed that the number count of ultrafine particles (diameter < 100 nm) – unlike PM2.5 – is not dramatically elevated in Delhi. Using observations and a simple model, we illustrate how the high amount of PM2.5 in Delhi may suppress ultrafine particle concentrations.
Leigh R. Crilley, Ajit Singh, Louisa J. Kramer, Marvin D. Shaw, Mohammed S. Alam, Joshua S. Apte, William J. Bloss, Lea Hildebrandt Ruiz, Pingqing Fu, Weiqi Fu, Shahzad Gani, Michael Gatari, Evgenia Ilyinskaya, Alastair C. Lewis, David Ng'ang'a, Yele Sun, Rachel C. W. Whitty, Siyao Yue, Stuart Young, and Francis D. Pope
Atmos. Meas. Tech., 13, 1181–1193, https://doi.org/10.5194/amt-13-1181-2020, https://doi.org/10.5194/amt-13-1181-2020, 2020
Short summary
Short summary
There is considerable interest in using low-cost optical particle counters (OPCs) for particle mass measurements; however, there is no agreed upon method with respect to calibration. Here we exploit a number of datasets globally to demonstrate that particle composition and relative humidity are the key factors affecting measured concentrations from a low-cost OPC, and we present a simple correction methodology that corrects for this influence.
Sahil Bhandari, Shahzad Gani, Kanan Patel, Dongyu S. Wang, Prashant Soni, Zainab Arub, Gazala Habib, Joshua S. Apte, and Lea Hildebrandt Ruiz
Atmos. Chem. Phys., 20, 735–752, https://doi.org/10.5194/acp-20-735-2020, https://doi.org/10.5194/acp-20-735-2020, 2020
Short summary
Short summary
Delhi, India, is the most polluted megacity on the planet, posing acute challenges to public health. We report on source apportionment conducted on 15 months of highly time-resolved mass spectrometer data. We find that severe air pollution episodes are dominated by primary organic aerosol, while secondary organic aerosol dominates the fractional contributions year-round, suggesting the importance of sources as well as their atmospheric processing on pollution levels in Delhi.
Shahzad Gani, Sahil Bhandari, Sarah Seraj, Dongyu S. Wang, Kanan Patel, Prashant Soni, Zainab Arub, Gazala Habib, Lea Hildebrandt Ruiz, and Joshua S. Apte
Atmos. Chem. Phys., 19, 6843–6859, https://doi.org/10.5194/acp-19-6843-2019, https://doi.org/10.5194/acp-19-6843-2019, 2019
Short summary
Short summary
Delhi experiences particulate matter concentrations that are among the highest in the world. We conducted a long-term campaign to make highly time-resolved measurements of submicron particle (PM1) chemical composition in Delhi. Our dataset illuminates key sources and atmospheric processes that impact Delhi's PM1 concentrations, with sharp differences among seasons and between day and night. In addition to local sources, Delhi's PM1 levels are amplified by regional pollution and meteorology.
Rishabh U. Shah, Ellis S. Robinson, Peishi Gu, Allen L. Robinson, Joshua S. Apte, and Albert A. Presto
Atmos. Chem. Phys., 18, 16325–16344, https://doi.org/10.5194/acp-18-16325-2018, https://doi.org/10.5194/acp-18-16325-2018, 2018
Short summary
Short summary
We measured spatial differences in airborne particulate matter (PM) in Oakland, CA, with repeated mobile measurements on all city streets. In addition to primary, we also find higher secondary organic PM downtown, which suggests stronger photochemical PM production in areas of high emissions and poor air ventilation (i.e., urban street canyons). This finding is original because while other modeling studies have predicted higher photochemistry in street canyons, we confirm this observationally.
Dongyu S. Wang and Lea Hildebrandt Ruiz
Atmos. Chem. Phys., 18, 15535–15553, https://doi.org/10.5194/acp-18-15535-2018, https://doi.org/10.5194/acp-18-15535-2018, 2018
Short summary
Short summary
We investigated the formation of atmospheric pollutants from chlorine-initiated oxidation of alkanes, which may occur in polluted environments. We report for the first the formation of alkane-derived chlorinated organics. We also propose a new approach to representing the chemical composition, volatility, and thermal desorption behavior of organic aerosols. Overall, our study suggests that the oxidation of alkanes can be an important source of organic aerosols in polluted environments.
Dongyu S. Wang and Lea Hildebrandt Ruiz
Atmos. Chem. Phys., 17, 13491–13508, https://doi.org/10.5194/acp-17-13491-2017, https://doi.org/10.5194/acp-17-13491-2017, 2017
Short summary
Short summary
We investigated the formation of atmospheric pollutants from chlorine-initiated oxidation of isoprene. Our study is the first to report formation of airborne particles from these reactions. We analyzed the chemical composition of both gas- and particle-phase products and propose methods to better detect particle-phase pollutants. Overall, our study demonstrates that reactions between isoprene and chlorine can have important implications for atmospheric composition and therefore human health.
Jeffrey K. Bean and Lea Hildebrandt Ruiz
Atmos. Chem. Phys., 16, 2175–2184, https://doi.org/10.5194/acp-16-2175-2016, https://doi.org/10.5194/acp-16-2175-2016, 2016
Short summary
Short summary
The fate of organic nitrates influences their role as sinks and sources of NOx and their effects on the formation of tropospheric ozone and organic aerosol. Organic nitrates were formed from the photo-oxidation of α-pinene in environmental chamber experiments. Results on partitioning and hydrolysis of organic nitrates from this work could be implemented in chemical transport models to more accurately represent the fate of NOx and the formation of ozone and particulate matter.
Andrea Paciga, Eleni Karnezi, Evangelia Kostenidou, Lea Hildebrandt, Magda Psichoudaki, Gabriella J. Engelhart, Byong-Hyoek Lee, Monica Crippa, André S. H. Prévôt, Urs Baltensperger, and Spyros N. Pandis
Atmos. Chem. Phys., 16, 2013–2023, https://doi.org/10.5194/acp-16-2013-2016, https://doi.org/10.5194/acp-16-2013-2016, 2016
Short summary
Short summary
We estimate the volatility distribution for the organic aerosol (OA) components during summer and winter field campaigns in Paris, France as part of the collaborative project MEGAPOLI. The OA factors (hydrocarbon like OA, cooking OA, marine OA, oxygenated OA) had a broad spectrum of volatilities with no direct link between the average volatility and average oxygen to carbon of the OA components.
M. Pikridas, J. Sciare, F. Freutel, S. Crumeyrolle, S.-L. von der Weiden-Reinmüller, A. Borbon, A. Schwarzenboeck, M. Merkel, M. Crippa, E. Kostenidou, M. Psichoudaki, L. Hildebrandt, G. J. Engelhart, T. Petäjä, A. S. H. Prévôt, F. Drewnick, U. Baltensperger, A. Wiedensohler, M. Kulmala, M. Beekmann, and S. N. Pandis
Atmos. Chem. Phys., 15, 10219–10237, https://doi.org/10.5194/acp-15-10219-2015, https://doi.org/10.5194/acp-15-10219-2015, 2015
Short summary
Short summary
Aerosol size distribution measurements from three ground sites, two mobile laboratories, and one airplane are combined to investigate the spatial and temporal variability of ultrafine particles in and around Paris during the summer and winter MEGAPOLI campaigns. The role of nucleation as a particle source and the influence of Paris emissions on their surroundings are examined.
L. Hildebrandt Ruiz, A. L. Paciga, K. M. Cerully, A. Nenes, N. M. Donahue, and S. N. Pandis
Atmos. Chem. Phys., 15, 8301–8313, https://doi.org/10.5194/acp-15-8301-2015, https://doi.org/10.5194/acp-15-8301-2015, 2015
Short summary
Short summary
Secondary organic aerosol (SOA) is transformed after its initial formation. We explored the effects of this chemical aging on the composition, mass yield, volatility, and hygroscopicity of SOA formed from the photo-oxidation of small aromatic volatile organic compounds. Higher exposure to the hydroxyl radical resulted in different SOA composition, average carbon oxidation state, and mass yield. The vapor pressure of SOA formed under different conditions varied by as much as a factor of 30.
M. R. Canagaratna, J. L. Jimenez, J. H. Kroll, Q. Chen, S. H. Kessler, P. Massoli, L. Hildebrandt Ruiz, E. Fortner, L. R. Williams, K. R. Wilson, J. D. Surratt, N. M. Donahue, J. T. Jayne, and D. R. Worsnop
Atmos. Chem. Phys., 15, 253–272, https://doi.org/10.5194/acp-15-253-2015, https://doi.org/10.5194/acp-15-253-2015, 2015
Short summary
Short summary
Atomic oxygen-to-carbon (O:C), hydrogen-to-carbon (H:C), and organic mass-to-organic carbon (OM:OC) ratios of ambient organic aerosol (OA) species provide key constraints for understanding their sources and impacts. Here an improved method for obtaining accurate O:C, H:C, and OM:OC with a widely used aerosol mass spectrometer is developed. These results imply that OA is more oxidized than previously estimated and indicate the need for new chemical mechanisms that simulate ambient oxidation.
T. Yli-Juuti, K. Barsanti, L. Hildebrandt Ruiz, A.-J. Kieloaho, U. Makkonen, T. Petäjä, T. Ruuskanen, M. Kulmala, and I. Riipinen
Atmos. Chem. Phys., 13, 12507–12524, https://doi.org/10.5194/acp-13-12507-2013, https://doi.org/10.5194/acp-13-12507-2013, 2013
M. R. Pennington, B. R. Bzdek, J. W. DePalma, J. N. Smith, A.-M. Kortelainen, L. Hildebrandt Ruiz, T. Petäjä, M. Kulmala, D. R. Worsnop, and M. V. Johnston
Atmos. Chem. Phys., 13, 10215–10225, https://doi.org/10.5194/acp-13-10215-2013, https://doi.org/10.5194/acp-13-10215-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Opinion: How will advances in aerosol science inform our understanding of the health impacts of outdoor particulate pollution?
Measurement report: Intra-annual variability of black carbon and brown carbon and their interrelation with meteorological conditions over Gangtok, Sikkim
Long-range transport of air pollutants increases the concentration of hazardous components of PM2.5 in northern South America
Dominant influence of biomass combustion and cross-border transport on nitrogen-containing organic compound levels in the southeastern Tibetan Plateau
Impacts of elevated anthropogenic emissions on physicochemical characteristics of black-carbon-containing particles over the Tibetan Plateau
Online characterization of primary and secondary emissions of particulate matter and acidic molecules from a modern fleet of city buses
Atmospheric evolution of environmentally persistent free radicals in the rural North China Plain: effects on water solubility and PM2.5 oxidative potential
Two distinct ship emission profiles for organic-sulfate source apportionment of PM in sulfur emission control areas
Automated compound speciation, cluster analysis, and quantification of organic vapors and aerosols using comprehensive two-dimensional gas chromatography and mass spectrometry
Measurement report: Occurrence of aminiums in PM2.5 during winter in China – aminium outbreak during polluted episodes and potential constraints
Bridging gas and aerosol properties between the northeastern US and Bermuda: analysis of eight transit flights
The behaviour of charged particles (ions) during new particle formation events in urban Leipzig, Germany
Exploring the sources of light-absorbing carbonaceous aerosols by integrating observational and modeling results: insights from Northeast China
Measurement report: Characteristics of airborne black-carbon-containing particles during the 2021 summer COVID-19 lockdown in a typical Yangtze River Delta city, China
Aerosol optical properties within the atmospheric boundary layer predicted from ground-based observations compared to Raman lidar retrievals during RITA-2021
Hygroscopic growth and activation changed submicron aerosol composition and properties in the North China Plain
Measurement report: Formation of tropospheric brown carbon in a lifting air mass
Vertical variability of aerosol properties and trace gases over a remote marine region: a case study over Bermuda
Differences in aerosol and cloud properties along the central California coast when winds change from northerly to southerly
International airport emissions and their impact on local air quality: chemical speciation of ambient aerosols at Madrid–Barajas Airport during the AVIATOR campaign
Significant role of biomass burning in heavy haze formation in a megacity: Molecular-level insights from intensive PM2.5 sampling on winter hazy days
The local ship speed reduction effect on black carbon emissions measured at a remote marine station
High-altitude aerosol chemical characterization and source identification: insights from the CALISHTO campaign
Measurement report: Impact of emission control measures on environmental persistent free radicals and reactive oxygen species – a short-term case study in Beijing
Characterizing water solubility of fresh and aged secondary organic aerosol in PM2.5 with the stable carbon isotope technique
Measurement report: Impact of cloud processes on secondary organic aerosols at a forested mountain site in southeastern China
Critical contribution of chemically diverse carbonyl molecules to the oxidative potential of atmospheric aerosols
Seasonal Investigation of Ultrafine Particle Composition in an Eastern Amazonian Rainforest
Measurement report: Vanadium-containing ship exhaust particles detected in and above the marine boundary layer in the remote atmosphere
Diverging trends in aerosol sulfate and nitrate measured in the remote North Atlantic in Barbados are attributed to clean air policies, African smoke, and anthropogenic emissions
Technical note: Quantified organic aerosol subsaturated hygroscopicity by a simple optical scatter monitor system through field measurements
Diverse sources and aging change the mixing state and ice nucleation properties of aerosol particles over the western Pacific and Southern Ocean
The water-insoluble organic carbon in PM2.5 of typical Chinese urban areas: light-absorbing properties, potential sources, radiative forcing effects, and a possible light-absorbing continuum
Measurement report: Size-resolved secondary organic aerosol formation modulated by aerosol water uptake in wintertime haze
In situ measurement of organic aerosol molecular markers in urban Hong Kong during a summer period: temporal variations and source apportionment
Technical note: Determining chemical composition of atmospheric single particles by a standard-free mass calibration algorithm
Different formation pathways of nitrogen-containing organic compounds in aerosols and fog water in northern China
Impact of weather patterns and meteorological factors on PM2.5 and O3 responses to the COVID-19 lockdown in China
Daytime and nighttime aerosol soluble iron formation in clean and slightly polluted moist air in a coastal city in eastern China
Non-negligible secondary contribution to brown carbon in autumn and winter: inspiration from particulate nitrated and oxygenated aromatic compounds in urban Beijing
A Multi-site Passive Approach for Studying the Emissions and Evolution of Smoke from Prescribed Fires
Non-sea-salt aerosols that contain trace bromine and iodine are widespread in the remote troposphere
Simultaneous organic aerosol source apportionment at two Antarctic sites reveals large-scale and ecoregion-specific components
Measurement report: Optical characterization, seasonality, and sources of brown carbon in fine aerosols from Tianjin, North China: year-round observations
High-resolution analyses of concentrations and sizes of black carbon particles deposited on northwest Greenland over the past 350 years – Part 2: Seasonal and temporal trends in black carbon originated from fossil fuel combustion and biomass burning
Bayesian inference-based estimation of hourly primary and secondary organic carbon in suburban Hong Kong: multi-temporal-scale variations and evolution characteristics during PM2.5 episodes
Formation and chemical evolution of SOA in two different environments: A dual chamber study
Enhanced daytime secondary aerosol formation driven by gas-particle partitioning in downwind urban plumes
Multiple eco-regions contribute to the seasonal cycle of Antarctic aerosol size distributions
Impact assessment of terrestrial and marine air-mass on the constituents and intermixing of bioaerosols over coastal atmosphere
Imad El Haddad, Danielle Vienneau, Kaspar R. Daellenbach, Robin Modini, Jay G. Slowik, Abhishek Upadhyay, Petros N. Vasilakos, David Bell, Kees de Hoogh, and Andre S. H. Prevot
Atmos. Chem. Phys., 24, 11981–12011, https://doi.org/10.5194/acp-24-11981-2024, https://doi.org/10.5194/acp-24-11981-2024, 2024
Short summary
Short summary
This opinion paper explores how advances in aerosol science inform our understanding of the health impacts of outdoor particulate pollution. We advocate for a shift in the way we target PM pollution, focusing on the most harmful anthropogenic emissions. We highlight key observations, modelling developments, and emission measurements needed to achieve this shift.
Pramod Kumar, Khushboo Sharma, Ankita Malu, Rajeev Rajak, Aparna Gupta, Bidyutjyoti Baruah, Shailesh Yadav, Thupstan Angchuk, Jayant Sharma, Rakesh Kumar Ranjan, Anil Kumar Misra, and Nishchal Wanjari
Atmos. Chem. Phys., 24, 11585–11601, https://doi.org/10.5194/acp-24-11585-2024, https://doi.org/10.5194/acp-24-11585-2024, 2024
Short summary
Short summary
This work monitors and assesses air pollution, especially black and brown carbon, its controlling factor, and its effect on the environment of Sikkim Himalayan region. The huge urban sprawl in recent decades has led to regional human-induced air pollution in the region. Black carbon was highest in April 2021 and March 2022, exceeding the WHO limit. The monsoon season causes huge rainfall over the region, which reduces the pollutants by scavenging (rainout and washout).
Maria P. Velásquez-García, K. Santiago Hernández, James A. Vergara-Correa, Richard J. Pope, Miriam Gómez-Marín, and Angela M. Rendón
Atmos. Chem. Phys., 24, 11497–11520, https://doi.org/10.5194/acp-24-11497-2024, https://doi.org/10.5194/acp-24-11497-2024, 2024
Short summary
Short summary
In the Aburrá Valley, northern South America, local emissions determine air quality conditions. However, we found that external sources, such as regional fires, Saharan dust, and volcanic emissions, increase particulate concentrations and worsen chemical composition by introducing elements like heavy metals. Dry winds and source variability contribute to seasonal influences on these events. This study assesses the air quality risks posed by such events, which can affect broad regions worldwide.
Meng Wang, Qiyuan Wang, Steven Sai Hang Ho, Jie Tian, Yong Zhang, Shun-cheng Lee, and Junji Cao
Atmos. Chem. Phys., 24, 11175–11189, https://doi.org/10.5194/acp-24-11175-2024, https://doi.org/10.5194/acp-24-11175-2024, 2024
Short summary
Short summary
We studied nitrogen-containing organic compounds (NOCs) in particulate matter <2.5 µm particles on the southeastern Tibetan Plateau. We found that biomass burning and transboundary transport are the main sources of NOCs in the high-altitude area. Understanding these aerosol sources informs how they add to regional and potentially global climate changes. Our findings could help shape effective environmental policies to enhance air quality and address climate impacts in this sensitive region.
Jinbo Wang, Jiaping Wang, Yuxuan Zhang, Tengyu Liu, Xuguang Chi, Xin Huang, Dafeng Ge, Shiyi Lai, Caijun Zhu, Lei Wang, Qiaozhi Zha, Ximeng Qi, Wei Nie, Congbin Fu, and Aijun Ding
Atmos. Chem. Phys., 24, 11063–11080, https://doi.org/10.5194/acp-24-11063-2024, https://doi.org/10.5194/acp-24-11063-2024, 2024
Short summary
Short summary
In this study, we found large spatial discrepancies in the physical and chemical properties of black carbon over the Tibetan Plateau (TP). Elevated anthropogenic emissions from low-altitude regions can significantly change the mass concentration, mixing state and chemical composition of black-carbon-containing aerosol in the TP region, further altering its light absorption ability. Our study emphasizes the vulnerability of remote plateau regions to intense anthropogenic influences.
Liyuan Zhou, Qianyun Liu, Christian M. Salvador, Michael Le Breton, Mattias Hallquist, Jian Zhen Yu, Chak K. Chan, and Åsa M. Hallquist
Atmos. Chem. Phys., 24, 11045–11061, https://doi.org/10.5194/acp-24-11045-2024, https://doi.org/10.5194/acp-24-11045-2024, 2024
Short summary
Short summary
Our research on city bus emissions reveals that alternative fuels (compressed natural gas and biofuels) reduce fresh particle emissions compared to diesel. However, all fuels lead to secondary air pollution. Aiming at guiding better environmental policies, we studied 76 buses using advanced emission measurement techniques. This work sheds light on the complex effects of bus fuels on urban air quality, emphasizing the need for comprehensive evaluations of future transportation technologies.
Xu Yang, Fobang Liu, Shuqi Yang, Yuling Yang, Yanan Wang, Jingjing Li, Mingyu Zhao, Zhao Wang, Kai Wang, Chi He, and Haijie Tong
Atmos. Chem. Phys., 24, 11029–11043, https://doi.org/10.5194/acp-24-11029-2024, https://doi.org/10.5194/acp-24-11029-2024, 2024
Short summary
Short summary
A study in the rural North China Plain showed environmentally persistent free radicals (EPFRs) in atmospheric particulate matter (PM), with a notable water-soluble fraction likely from atmospheric oxidation during transport. Significant positive correlations between EPFRs and the water-soluble oxidative potential of PM2.5 were found, primarily attributable to the water-soluble fractions of EPFRs. These findings emphasize understanding EPFRs' atmospheric evolution for climate and health impacts.
Kirsten N. Fossum, Chunshui Lin, Niall O'Sullivan, Lu Lei, Stig Hellebust, Darius Ceburnis, Aqeel Afzal, Anja Tremper, David Green, Srishti Jain, Steigvilė Byčenkienė, Colin O'Dowd, John Wenger, and Jurgita Ovadnevaite
Atmos. Chem. Phys., 24, 10815–10831, https://doi.org/10.5194/acp-24-10815-2024, https://doi.org/10.5194/acp-24-10815-2024, 2024
Short summary
Short summary
The chemical composition and sources of submicron aerosol in the Dublin Port area were investigated over a month-long campaign. Two distinct types of ship emissions were identified and characterised: sulfate-rich plumes from the use of heavy fuel oil with scrubbers and organic-rich plumes from the use of low-sulfur fuels. The latter were more frequent, emitting double the particle number and having a typical V / Ni ratio for ship emission.
Xiao He, Xuan Zheng, Shuwen Guo, Lewei Zeng, Ting Chen, Bohan Yang, Shupei Xiao, Qiongqiong Wang, Zhiyuan Li, Yan You, Shaojun Zhang, and Ye Wu
Atmos. Chem. Phys., 24, 10655–10666, https://doi.org/10.5194/acp-24-10655-2024, https://doi.org/10.5194/acp-24-10655-2024, 2024
Short summary
Short summary
This study introduces an innovative method for identifying and quantifying complex organic vapors and aerosols. By combining advanced analytical techniques and new algorithms, we categorized thousands of compounds from heavy-duty diesel vehicles and ambient air and highlighted specific tracers for emission sources. The innovative approach enhances peak identification, reduces quantification uncertainties, and offers new insights for air quality management and atmospheric chemistry.
Yu Xu, Tang Liu, Yi-Jia Ma, Qi-Bin Sun, Hong-Wei Xiao, Hao Xiao, Hua-Yun Xiao, and Cong-Qiang Liu
Atmos. Chem. Phys., 24, 10531–10542, https://doi.org/10.5194/acp-24-10531-2024, https://doi.org/10.5194/acp-24-10531-2024, 2024
Short summary
Short summary
This study investigates the characteristics of aminiums and ammonium in PM2.5 on clean and polluted winter days in 11 Chinese cities, highlighting the possibility of the competitive uptake of ammonia versus amines on acidic aerosols or the displacement of aminiums by ammonia under high-ammonia conditions. The overall results deepen the understanding of the spatiotemporal differences in aminium characteristics and formation in China.
Cassidy Soloff, Taiwo Ajayi, Yonghoon Choi, Ewan C. Crosbie, Joshua P. DiGangi, Glenn S. Diskin, Marta A. Fenn, Richard A. Ferrare, Francesca Gallo, Johnathan W. Hair, Miguel Ricardo A. Hilario, Simon Kirschler, Richard H. Moore, Taylor J. Shingler, Michael A. Shook, Kenneth L. Thornhill, Christiane Voigt, Edward L. Winstead, Luke D. Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 24, 10385–10408, https://doi.org/10.5194/acp-24-10385-2024, https://doi.org/10.5194/acp-24-10385-2024, 2024
Short summary
Short summary
Using aircraft measurements over the northwestern Atlantic between the US East Coast and Bermuda and trajectory modeling of continental outflow, we identify trace gas and particle properties that exhibit gradients with offshore distance and quantify these changes with high-resolution measurements of concentrations and particle chemistry, size, and scattering properties. This work furthers our understanding of the complex interactions between continental and marine environments.
Alex Rowell, James Brean, David C. S. Beddows, Zongbo Shi, Avinash Kumar, Matti Rissanen, Miikka Dal Maso, Peter Mettke, Kay Weinhold, Maik Merkel, and Roy M. Harrison
Atmos. Chem. Phys., 24, 10349–10361, https://doi.org/10.5194/acp-24-10349-2024, https://doi.org/10.5194/acp-24-10349-2024, 2024
Short summary
Short summary
Ions enhance the formation and growth rates of new particles, affecting the Earth's radiation budget. Despite these effects, there is little published data exploring the sources of ions in the urban environment and their role in new particle formation (NPF). Here we show that natural ion sources dominate in urban environments, while traffic is a secondary source. Ions contribute up to 12.7 % of the formation rate of particles, indicating that they are important for forming urban PM.
Yuan Cheng, Xu-bing Cao, Sheng-qiang Zhu, Zhi-qing Zhang, Jiu-meng Liu, Hong-liang Zhang, Qiang Zhang, and Ke-bin He
Atmos. Chem. Phys., 24, 9869–9883, https://doi.org/10.5194/acp-24-9869-2024, https://doi.org/10.5194/acp-24-9869-2024, 2024
Short summary
Short summary
The agreement between observational and modeling results is essential for the development of efficient air pollution control strategies. Here we constrained the modeling results of carbonaceous aerosols by field observation in Northeast China, a historically overlooked but recently targeted region of national clean-air actions. Our study suggested that the simulation of agricultural fire emissions and secondary organic aerosols remains challenging.
Yuan Dai, Junfeng Wang, Houjun Wang, Shijie Cui, Yunjiang Zhang, Haiwei Li, Yun Wu, Ming Wang, Eleonora Aruffo, and Xinlei Ge
Atmos. Chem. Phys., 24, 9733–9748, https://doi.org/10.5194/acp-24-9733-2024, https://doi.org/10.5194/acp-24-9733-2024, 2024
Short summary
Short summary
Short-term strict emission control can improve air quality, but its effectiveness needs assessment. During the 2021 summer COVID-19 lockdown in Yangzhou, we found that PM2.5 levels did not decrease despite reduced primary emissions. Aged black-carbon particles increased substantially due to higher O3 levels and transported pollutants. High humidity and low wind also played key roles. The results highlight the importance of a regionally balanced control strategy for future air quality management.
Xinya Liu, Diego Alves Gouveia, Bas Henzing, Arnoud Apituley, Arjan Hensen, Danielle van Dinther, Rujin Huang, and Ulrike Dusek
Atmos. Chem. Phys., 24, 9597–9614, https://doi.org/10.5194/acp-24-9597-2024, https://doi.org/10.5194/acp-24-9597-2024, 2024
Short summary
Short summary
The vertical distribution of aerosol optical properties is important for their effect on climate. This is usually measured by lidar, which has limitations, most notably the assumption of a lidar ratio. Our study shows that routine surface-level aerosol measurements are able to predict this lidar ratio reasonably well within the lower layers of the atmosphere and thus provide a relatively simple and cost-effective method to improve lidar measurements.
Weiqi Xu, Ye Kuang, Wanyun Xu, Zhiqiang Zhang, Biao Luo, Xiaoyi Zhang, Jiangchuang Tao, Hongqin Qiao, Li Liu, and Yele Sun
Atmos. Chem. Phys., 24, 9387–9399, https://doi.org/10.5194/acp-24-9387-2024, https://doi.org/10.5194/acp-24-9387-2024, 2024
Short summary
Short summary
We deployed an advanced aerosol–fog sampling system at a rural site in the North China Plain to investigate impacts of aerosol hygroscopic growth and activation on the physicochemical properties of submicron aerosols. Observed results highlighted remarkably different aqueous processing of primary and secondary submicron aerosol components under distinct ambient relative humidity (RH) conditions and that RH levels significantly impact aerosol sampling through the aerosol swelling effect.
Can Wu, Xiaodi Liu, Ke Zhang, Si Zhang, Cong Cao, Jianjun Li, Rui Li, Fan Zhang, and Gehui Wang
Atmos. Chem. Phys., 24, 9263–9275, https://doi.org/10.5194/acp-24-9263-2024, https://doi.org/10.5194/acp-24-9263-2024, 2024
Short summary
Short summary
Brown carbon (BrC) is prevalent in the troposphere and can efficiently absorb solar and terrestrial radiation. Our observations show that the enhanced light absorption of BrC relative to black carbon at the tropopause can be attributed to the formation of nitrogen-containing organic compounds through the aqueous-phase reactions of carbonyls with ammonium.
Taiwo Ajayi, Yonghoon Choi, Ewan C. Crosbie, Joshua P. DiGangi, Glenn S. Diskin, Marta A. Fenn, Richard A. Ferrare, Johnathan W. Hair, Miguel Ricardo A. Hilario, Chris A. Hostetler, Simon Kirschler, Richard H. Moore, Taylor J. Shingler, Michael A. Shook, Cassidy Soloff, Kenneth L. Thornhill, Christiane Voigt, Edward L. Winstead, Luke D. Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 24, 9197–9218, https://doi.org/10.5194/acp-24-9197-2024, https://doi.org/10.5194/acp-24-9197-2024, 2024
Short summary
Short summary
This study uses airborne data to examine vertical profiles of trace gases, aerosol particles, and meteorological variables over a remote marine area (Bermuda). Results show distinct differences based on both air mass source region (North America, Ocean, Caribbean/North Africa) and altitude for a given air mass type. This work highlights the sensitivity of remote marine areas to long-range transport and the importance of considering the vertical dependence of trace gas and aerosol properties.
Kira Zeider, Grace Betito, Anthony Bucholtz, Peng Xian, Annette Walker, and Armin Sorooshian
Atmos. Chem. Phys., 24, 9059–9083, https://doi.org/10.5194/acp-24-9059-2024, https://doi.org/10.5194/acp-24-9059-2024, 2024
Short summary
Short summary
The predominant wind direction along the California coast (northerly) reverses several times during the summer (to southerly). The effects of these wind reversals on aerosol and cloud characteristics are not well understood. Using data from multiple datasets we found that southerly flow periods had enhanced signatures of anthropogenic emissions due to shipping and continental sources, and clouds had more but smaller droplets.
Saleh Alzahrani, Doğuşhan Kılıç, Michael Flynn, Paul I. Williams, and James Allan
Atmos. Chem. Phys., 24, 9045–9058, https://doi.org/10.5194/acp-24-9045-2024, https://doi.org/10.5194/acp-24-9045-2024, 2024
Short summary
Short summary
This paper investigates emissions from aviation activities at an international airport to evaluate their impact on local air quality. The study provides detailed insights into the chemical composition of aerosols and key pollutants in the airport environment. Source apportionment analysis using positive matrix factorisation (PMF) identified three significant sources: less oxidised oxygenated organic aerosol, alkane organic aerosol, and more oxidised oxygenated organic aerosol.
Mingjie Kang, Mengying Bao, Wenhuai Song, Aduburexiati Abulimiti, Fang Cao, Sönke Szidat, and Yanlin Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2024-2098, https://doi.org/10.5194/egusphere-2024-2098, 2024
Short summary
Short summary
Reports on the molecular level knowledge of high temporal resolution PM2.5 components on hazy days are still limited. This study investigated many individual PM2.5 species and sources. The results show biomass burning (BB) was the main source of organic carbon. Moreover, BB enhanced fungal spore emissions and secondary aerosol formation. The contribution of non-fossils increased with increasing haze pollution. These findings suggest BB may be an important driver of haze events in winter.
Mikko Heikkilä, Krista Luoma, Timo Mäkelä, and Tiia Grönholm
Atmos. Chem. Phys., 24, 8927–8941, https://doi.org/10.5194/acp-24-8927-2024, https://doi.org/10.5194/acp-24-8927-2024, 2024
Short summary
Short summary
Black carbon (BC) concentration was measured from 211 ship exhaust gas plumes at a remote marine station. Emission factors of BC were calculated in grams per kilogram of fuel. Ships with an exhaust gas cleaning system (EGCS) were found to have median BC emissions per fuel consumed 5 times lower than ships without an EGCS. However, this might be because of non-EGCS ships running at low engine loads rather than the EGCS itself. A local speed restriction would increase BC emissions of ships.
Olga Zografou, Maria Gini, Prodromos Fetfatzis, Konstantinos Granakis, Romanos Foskinis, Manousos Ioannis Manousakas, Fotios Tsopelas, Evangelia Diapouli, Eleni Dovrou, Christina N. Vasilakopoulou, Alexandros Papayannis, Spyros N. Pandis, Athanasios Nenes, and Konstantinos Eleftheriadis
Atmos. Chem. Phys., 24, 8911–8926, https://doi.org/10.5194/acp-24-8911-2024, https://doi.org/10.5194/acp-24-8911-2024, 2024
Short summary
Short summary
Characterization of PM1 and positive matrix factorization (PMF) source apportionment of organic and inorganic fractions were conducted at the high-altitude station (HAC)2. Cloud presence reduced PM1, affecting sulfate more than organics. Free-troposphere (FT) conditions showed more black carbon (eBC) than planetary boundary layer (PBL) conditions.
Yuanyuan Qin, Xinghua Zhang, Wei Huang, Juanjuan Qin, Xiaoyu Hu, Yuxuan Cao, Tianyi Zhao, Yang Zhang, Jihua Tan, Ziyin Zhang, Xinming Wang, and Zhenzhen Wang
Atmos. Chem. Phys., 24, 8737–8750, https://doi.org/10.5194/acp-24-8737-2024, https://doi.org/10.5194/acp-24-8737-2024, 2024
Short summary
Short summary
Environmental persistent free radicals (EPFRs) and reactive oxygen species (ROSs) play an active role in the atmosphere. Despite control measures having effectively reduced their emissions, reductions were less than in PM2.5. Emission control measures performed well in achieving Parade Blue, but reducing the impact of the atmosphere on human health remains challenging. Thus, there is a need to reassess emission control measures to better address the challenges posed by EPFRs and ROSs.
Fenghua Wei, Xing Peng, Liming Cao, Mengxue Tang, Ning Feng, Xiaofeng Huang, and Lingyan He
Atmos. Chem. Phys., 24, 8507–8518, https://doi.org/10.5194/acp-24-8507-2024, https://doi.org/10.5194/acp-24-8507-2024, 2024
Short summary
Short summary
The water solubility of secondary organic aerosols (SOAs) is a crucial factor in determining their hygroscopicity and climatic impact. Stable carbon isotope and mass spectrometry techniques were combined to assess the water solubility of SOAs with different aging degrees in a coastal megacity in China. This work revealed a much higher water-soluble fraction of aged SOA compared to fresh SOA, indicating that the aging degree of SOA has considerable impacts on its water solubility.
Zijun Zhang, Weiqi Xu, Yi Zhang, Wei Zhou, Xiangyu Xu, Aodong Du, Yinzhou Zhang, Hongqin Qiao, Ye Kuang, Xiaole Pan, Zifa Wang, Xueling Cheng, Lanzhong Liu, Qingyan Fu, Douglas R. Worsnop, Jie Li, and Yele Sun
Atmos. Chem. Phys., 24, 8473–8488, https://doi.org/10.5194/acp-24-8473-2024, https://doi.org/10.5194/acp-24-8473-2024, 2024
Short summary
Short summary
We investigated aerosol composition and sources and the interaction between secondary organic aerosol (SOA) and clouds at a regional mountain site in southeastern China. Clouds efficiently scavenge more oxidized SOA; however, cloud evaporation leads to the production of less oxidized SOA. The unexpectedly high presence of nitrate in aerosol particles indicates that nitrate formed in polluted areas has undergone interactions with clouds, significantly influencing the regional background site.
Feifei Li, Shanshan Tang, Jitao Lv, Shiyang Yu, Xu Sun, Dong Cao, Yawei Wang, and Guibin Jiang
Atmos. Chem. Phys., 24, 8397–8411, https://doi.org/10.5194/acp-24-8397-2024, https://doi.org/10.5194/acp-24-8397-2024, 2024
Short summary
Short summary
Targeted derivatization and non-targeted analysis with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) were used to reveal the molecular composition of carbonyl molecules in PM2.5, and the important role of carbonyls in increasing the oxidative potential of organic aerosol was found in real samples.
Adam E. Thomas, Hayley S. Glicker, Alex B. Guenther, Roger Seco, Oscar Vega Bustillos, Julio Tota, Rodrigo A. F. Souza, and James N. Smith
EGUsphere, https://doi.org/10.5194/egusphere-2024-2230, https://doi.org/10.5194/egusphere-2024-2230, 2024
Short summary
Short summary
We present measurements of the composition of ultrafine particles collected from the eastern Amazon, a relatively understudied region that is subjected to increasing human influence. We find that while isoprene chemistry is likely significant to ultrafine particle growth throughout the year, compounds related to other sources such as biological spore emissions and biomass burning exhibit striking seasonal differences, implying an extensive variation in regional ultrafine particle sources.
Maya Abou-Ghanem, Daniel M. Murphy, Gregory P. Schill, Michael J. Lawler, and Karl D. Froyd
Atmos. Chem. Phys., 24, 8263–8275, https://doi.org/10.5194/acp-24-8263-2024, https://doi.org/10.5194/acp-24-8263-2024, 2024
Short summary
Short summary
Using particle analysis by laser mass spectrometry, we examine vanadium-containing ship exhaust particles measured on NASA's DC-8 during the Atmospheric Tomography Mission (ATom). Our results reveal ship exhaust particles are sufficiently widespread in the marine atmosphere and experience atmospheric aging. Finally, we use laboratory calibrations to determine the vanadium, sulfate, and organic single-particle mass fractions of vanadium-containing ship exhaust particles.
Cassandra J. Gaston, Joseph M. Prospero, Kristen Foley, Havala O. T. Pye, Lillian Custals, Edmund Blades, Peter Sealy, and James A. Christie
Atmos. Chem. Phys., 24, 8049–8066, https://doi.org/10.5194/acp-24-8049-2024, https://doi.org/10.5194/acp-24-8049-2024, 2024
Short summary
Short summary
To understand how changing emissions have impacted aerosols in remote regions, we measured nitrate and sulfate in Barbados and compared them to model predictions from EPA’s Air QUAlity TimE Series (EQUATES). Nitrate was stable, except for spikes in 2008 and 2010 due to transported smoke. Sulfate decreased in the 1990s due to reductions in sulfur dioxide (SO2) in the US and Europe; then it increased in the 2000s, likely due to anthropogenic emissions from Africa.
Jie Zhang, Tianyu Zhu, Alexandra Catena, Yaowei Li, Margaret Schwab, Pengfei Liu, Akua Asa-Awuku, and James Schwab
EGUsphere, https://doi.org/10.5194/egusphere-2024-1390, https://doi.org/10.5194/egusphere-2024-1390, 2024
Short summary
Short summary
This study shows the derived organic aerosol hygroscopicity under high humidity conditions based on a simple optical scatter monitor system, including two nephelometric monitors (pDR-1500), after knowing the aerosol chemical composition.
Jiao Xue, Tian Zhang, Keyhong Park, Jinpei Yan, Young Jun Yoon, Jiyeon Park, and Bingbing Wang
Atmos. Chem. Phys., 24, 7731–7754, https://doi.org/10.5194/acp-24-7731-2024, https://doi.org/10.5194/acp-24-7731-2024, 2024
Short summary
Short summary
Ice formation by particles is an important way of making mixed-phase and ice clouds. We found that particles collected in the marine atmosphere exhibit diverse ice nucleation abilities and mixing states. Sea salt mixed-sulfate particles were enriched in ice-nucleating particles. Selective aging on sea salt particles made particle populations more externally mixed. Characterizations of particles and their mixing state are needed for a better understanding of aerosol–cloud interactions.
Yangzhi Mo, Jun Li, Guangcai Zhong, Sanyuan Zhu, Shizhen Zhao, Jiao Tang, Hongxing Jiang, Zhineng Cheng, Chongguo Tian, Yingjun Chen, and Gan Zhang
Atmos. Chem. Phys., 24, 7755–7772, https://doi.org/10.5194/acp-24-7755-2024, https://doi.org/10.5194/acp-24-7755-2024, 2024
Short summary
Short summary
In this study, we found that biomass burning (31.0 %) and coal combustion (31.1 %) were the dominant sources of water-insoluble organic carbon in China, with coal combustion sources exhibiting the strongest light-absorbing capacity. Additionally, we propose a light-absorbing carbonaceous continuum, revealing that components enriched with fossil sources tend to have stronger light-absorbing capacity, higher aromaticity, higher molecular weights, and greater recalcitrance in the atmosphere.
Jing Duan, Ru-Jin Huang, Ying Wang, Wei Xu, Haobin Zhong, Chunshui Lin, Wei Huang, Yifang Gu, Jurgita Ovadnevaite, Darius Ceburnis, and Colin O'Dowd
Atmos. Chem. Phys., 24, 7687–7698, https://doi.org/10.5194/acp-24-7687-2024, https://doi.org/10.5194/acp-24-7687-2024, 2024
Short summary
Short summary
The chemical composition of atmospheric particles has shown significant changes in recent years. We investigated the potential effects of changes in inorganics on aerosol water uptake and, thus, secondary organic aerosol formation in wintertime haze based on the size-resolved measurements of non-refractory fine particulate matter (NR-PM2.5) in Xi’an, northwestern China. We highlight the key role of aerosol water as a medium to link inorganics and organics in their multiphase processes.
Hongyong Li, Xiaopu Lyu, Likun Xue, Yunxi Huo, Dawen Yao, Haoxian Lu, and Hai Guo
Atmos. Chem. Phys., 24, 7085–7100, https://doi.org/10.5194/acp-24-7085-2024, https://doi.org/10.5194/acp-24-7085-2024, 2024
Short summary
Short summary
Organic aerosol is ubiquitous in the atmosphere and largely explains the gap between current levels of fine particulate matter in many cities and the World Health Organization guideline values. This study highlights the dominant contributions of cooking emissions to organic aerosol when marine air prevailed in Hong Kong, which were occasionally overwhelmed by aromatics-derived secondary organic aerosol in continental ouflows.
Shao Shi, Jinghao Zhai, Xin Yang, Yechun Ruan, Yuanlong Huang, Xujian Chen, Antai Zhang, Jianhuai Ye, Guomao Zheng, Baohua Cai, Yaling Zeng, Yixiang Wang, Chunbo Xing, Yujie Zhang, Tzung-May Fu, Lei Zhu, Huizhong Shen, and Chen Wang
Atmos. Chem. Phys., 24, 7001–7012, https://doi.org/10.5194/acp-24-7001-2024, https://doi.org/10.5194/acp-24-7001-2024, 2024
Short summary
Short summary
The determination of ions in the mass spectra of individual particles remains uncertain. We have developed a standard-free mass calibration algorithm applicable to more than 98 % of ambient particles. With our algorithm, ions with ~ 0.05 Th mass difference could be determined. Therefore, many more atmospheric species could be determined and involved in the source apportionment of aerosols, the study of chemical reaction mechanisms, and the analysis of single-particle mixing states.
Wei Sun, Xiaodong Hu, Yuzhen Fu, Guohua Zhang, Yujiao Zhu, Xinfeng Wang, Caiqing Yan, Likun Xue, He Meng, Bin Jiang, Yuhong Liao, Xinming Wang, Ping'an Peng, and Xinhui Bi
Atmos. Chem. Phys., 24, 6987–6999, https://doi.org/10.5194/acp-24-6987-2024, https://doi.org/10.5194/acp-24-6987-2024, 2024
Short summary
Short summary
The formation pathways of nitrogen-containing compounds (NOCs) in the atmosphere remain unclear. We investigated the composition of aerosols and fog water by state-of-the-art mass spectrometry and compared the formation pathways of NOCs. We found that NOCs in aerosols were mainly formed through nitration reaction, while ammonia addition played a more important role in fog water. The results deepen our understanding of the processes of organic particulate pollution.
Fuzhen Shen, Michaela I. Hegglin, and Yue Yuan
Atmos. Chem. Phys., 24, 6539–6553, https://doi.org/10.5194/acp-24-6539-2024, https://doi.org/10.5194/acp-24-6539-2024, 2024
Short summary
Short summary
We attempt to use a novel structural self-organising map and machine learning models to identify a weather system and quantify the importance of each meteorological factor in driving the unexpected PM2.5 and O3 changes under the specific weather system during the COVID-19 lockdown in China. The result highlights that temperature under the double-centre high-pressure system plays the most crucial role in abnormal events.
Wenshuai Li, Yuxuan Qi, Yingchen Liu, Guanru Wu, Yanjing Zhang, Jinhui Shi, Wenjun Qu, Lifang Sheng, Wencai Wang, Daizhou Zhang, and Yang Zhou
Atmos. Chem. Phys., 24, 6495–6508, https://doi.org/10.5194/acp-24-6495-2024, https://doi.org/10.5194/acp-24-6495-2024, 2024
Short summary
Short summary
Aerosol particles from mainland can transport to oceans and deposit, providing soluble Fe and affecting phytoplankton growth. Thus, we studied the dissolution process of aerosol Fe and found that photochemistry played a key role in promoting Fe dissolution in clean conditions. RH-dependent reactions were more influential in slightly polluted conditions. These results highlight the distinct roles of two weather-related parameters (radiation and RH) in influencing geochemical cycles related to Fe.
Yanqin Ren, Zhenhai Wu, Yuanyuan Ji, Fang Bi, Junling Li, Haijie Zhang, Hao Zhang, Hong Li, and Gehui Wang
Atmos. Chem. Phys., 24, 6525–6538, https://doi.org/10.5194/acp-24-6525-2024, https://doi.org/10.5194/acp-24-6525-2024, 2024
Short summary
Short summary
Nitrated aromatic compounds (NACs) and oxygenated derivatives of polycyclic aromatic hydrocarbons (OPAHs) in PM2.5 were examined from an urban area in Beijing during the autumn and winter. The OPAH and NAC concentrations were much higher during heating than before heating. They majorly originated from the combustion of biomass and automobile emissions, and the secondary generation was the major contributor throughout the whole sampling period.
Rime El Asmar, Zongrun Li, David J. Tanner, Yongtao Hu, Susan O’Neill, L. Gregory Huey, M. Talat Odman, and Rodney J. Weber
EGUsphere, https://doi.org/10.5194/egusphere-2024-1485, https://doi.org/10.5194/egusphere-2024-1485, 2024
Short summary
Short summary
Prescribed burning is an important method for managing ecosystems and preventing wildfires, however, smoke from prescribed fires can have a significant impact on air quality. Here, using a network of fixed sites and sampling throughout an extended prescribed burning period in two different years, we characterize the emissions and evolution up to 8 hours of PM2.5 mass, BC, and BrC in smoke from burning of forested lands in the southeastern US.
Gregory P. Schill, Karl D. Froyd, Daniel M. Murphy, Christina J. Williamson, Charles Brock, Tomás Sherwen, Mat J. Evans, Eric A. Ray, Eric C. Apel, Rebecca S. Hornbrook, Alan J. Hills, Jeff Peischl, Tomas B. Ryerson, Chelsea R. Thompson, Ilann Bourgeois, Donald R. Blake, Joshua P. DiGangi, and Glenn S. Diskin
EGUsphere, https://doi.org/10.5194/egusphere-2024-1399, https://doi.org/10.5194/egusphere-2024-1399, 2024
Short summary
Short summary
Using single-particle mass spectrometry, we show that trace concentrations of bromine and iodine are ubiquitous in remote tropospheric aerosol, and suggest that aerosols are an important part of the global reactive iodine budget. Comparisons to a global climate model with detailed iodine chemistry are favorable in the background atmosphere; however, the model cannot replicate our measurements near the ocean surface, in biomass burning plumes, and in the stratosphere.
Marco Paglione, David C. S. Beddows, Anna Jones, Thomas Lachlan-Cope, Matteo Rinaldi, Stefano Decesari, Francesco Manarini, Mara Russo, Karam Mansour, Roy M. Harrison, Andrea Mazzanti, Emilio Tagliavini, and Manuel Dall'Osto
Atmos. Chem. Phys., 24, 6305–6322, https://doi.org/10.5194/acp-24-6305-2024, https://doi.org/10.5194/acp-24-6305-2024, 2024
Short summary
Short summary
Applying factor analysis techniques to H-NMR spectra, we present the organic aerosol (OA) source apportionment of PM1 samples collected in parallel at two Antarctic stations, namely Signy and Halley, allowing investigation of aerosol–climate interactions in an unperturbed atmosphere. Our results show remarkable differences between pelagic (open-ocean) and sympagic (sea-ice-influenced) air masses and indicate that various sources and processes are controlling Antarctic aerosols.
Zhichao Dong, Chandra Mouli Pavuluri, Peisen Li, Zhanjie Xu, Junjun Deng, Xueyan Zhao, Xiaomai Zhao, Pingqing Fu, and Cong-Qiang Liu
Atmos. Chem. Phys., 24, 5887–5905, https://doi.org/10.5194/acp-24-5887-2024, https://doi.org/10.5194/acp-24-5887-2024, 2024
Short summary
Short summary
Comprehensive study of optical properties of brown carbon (BrC) in fine aerosols from Tianjin, China, implied that biological emissions are major sources of BrC in summer, whereas fossil fuel combustion and biomass burning emissions are in cold periods. The direct radiation absorption caused by BrC in short wavelengths contributed about 40 % to that caused by BrC in 300–700 nm. Water-insoluble but methanol-soluble BrC contains more protein-like chromophores (PLOM) than that of water-soluble BrC.
Kumiko Goto-Azuma, Yoshimi Ogawa-Tsukagawa, Kaori Fukuda, Koji Fujita, Motohiro Hirabayashi, Remi Dallmayr, Jun Ogata, Nobuhiro Moteki, Tatsuhiro Mori, Sho Ohata, Yutaka Kondo, Makoto Koike, Sumito Matoba, and Teruo Aoki
EGUsphere, https://doi.org/10.5194/egusphere-2024-1498, https://doi.org/10.5194/egusphere-2024-1498, 2024
Short summary
Short summary
Monthly records spanning 350 years from a Greenland ice core reveal trends in black carbon (BC) concentrations and sizes. BC concentrations have risen since the late 19th century due to the inflow of anthropogenic BC, with these particles being larger than those from biomass burning (BB). High BB BC concentration peaks in summer originating from BB could reduce albedo. However, BB BC showed no upward trend until the early 2000s. Our findings are crucial for validating aerosol and climate models.
Shan Wang, Kezheng Liao, Zijing Zhang, Yuk Ying Cheng, Qiongqiong Wang, Hanzhe Chen, and Jian Zhen Yu
Atmos. Chem. Phys., 24, 5803–5821, https://doi.org/10.5194/acp-24-5803-2024, https://doi.org/10.5194/acp-24-5803-2024, 2024
Short summary
Short summary
In this work, hourly primary and secondary organic carbon were estimated by a novel Bayesian inference approach in suburban Hong Kong. Their multi-temporal-scale variations and evolution characteristics during PM2.5 episodes were examined. The methodology could serve as a guide for other locations with similar monitoring capabilities. The observation-based results are helpful for understanding the evolving nature of secondary organic aerosols and refining the accuracy of model simulations.
Andreas Aktypis, Dontavious Sippial, Christina Vasilakopoulou, Angeliki Matrali, Christos Kaltsonoudis, Andrea Simonati, Marco Paglione, Matteo Rinaldi, Stefano Decesari, and Spyros Pandis
EGUsphere, https://doi.org/10.5194/egusphere-2024-1317, https://doi.org/10.5194/egusphere-2024-1317, 2024
Short summary
Short summary
A dual chamber system was deployed in two different environments (Po Valley, Italy and Pertouli forest, Greece) to study the potential of ambient air directly injected into the chambers, to form secondary aerosol. In the Po Valley, the system reacts rapidly forming large amounts of SOA, while in Pertouli the corresponding SOA formation chemistry appears to have been practically terminated before the beginning of most experiments, so there is little additional SOA formation potential left.
Mingfu Cai, Chenshuo Ye, Bin Yuan, Shan Huang, E Zheng, Suxia Yang, Zelong Wang, Yi Lin, Tiange Li, Weiwei Hu, Wei Chen, Qicong Song, Wei Li, Yuwen Peng, Baolin Liang, Qibin Sun, Jun Zhao, Duohong Chen, Jiaren Sun, Zhiyong Yang, and Min Shao
EGUsphere, https://doi.org/10.5194/egusphere-2024-887, https://doi.org/10.5194/egusphere-2024-887, 2024
Short summary
Short summary
This study investigated the daytime secondary organic aerosol (SOA) formation in urban plumes. We observed a significant daytime SOA formation through gas-particle partitioning when the site was affected by urban plumes. Box model simulation indicated that urban pollutants (nitrogen oxide and volatile organic compounds) could enhance the oxidizing capacity, while the elevated volatile organic compounds were mainly responsible for promoting daytime SOA formation.
James Brean, David C. S. Beddows, Eija Asmi, Ari Virkkula, Lauriane L. J. Quéléver, Mikko Sipilä, Floortje Van Den Heuvel, Thomas Lachlan-Cope, Anna Jones, Markus Frey, Angelo Lupi, Jiyeon Park, Young Jun Yoon, Ralf Weller, Giselle L. Marincovich, Gabriela C. Mulena, Roy M. Harrison, and Manuel Dall´Osto
EGUsphere, https://doi.org/10.5194/egusphere-2024-987, https://doi.org/10.5194/egusphere-2024-987, 2024
Short summary
Short summary
Our results emphasize how understanding the geographical variation in surface types across the Antarctic is key to understanding secondary aerosol sources.
Qun He, Zhaowen Wang, Houfeng Liu, Pengju Xu, Rongbao Duan, Caihong Xu, Jianmin Chen, and Min Wei
EGUsphere, https://doi.org/10.5194/egusphere-2024-841, https://doi.org/10.5194/egusphere-2024-841, 2024
Short summary
Short summary
Coastal environments provide an ideal setting for investigating the intermixing processes of terrestrial and marine aerosols. Terrestrial air mass constituted a larger proportion during severe air pollution, harboring more animal and human pathogens. A relative shift towards marine air-mass with respect to pollution elimination, where saprophytic bacteria and fungi were predominant. Mixed air-mass reveals the intermixing processes of terrestrial and marine sources.
Cited articles
Andreae, M. O. and Rosenfeld, D.: Aerosol–cloud–precipitation
interactions. Part 1. The nature and sources of cloud-active
aerosols, Earth-Sci. Rev., 89, 13–41,
https://doi.org/10.1016/j.earscirev.2008.03.001, 2008.
Arub, Z., Bhandari, S., Gani, S., Apte, J. S., Hildebrandt Ruiz, L., and Habib, G.:
rawdata_arubetal2020.xlsx, available at: http://web.iitd.ac.in/~gazala/rawdata_arubetal2020.xlsx, last access: 6 June 2020.
Asa-Awuku, A., Moore, R. H., Nenes, A., Bahreini, R., Holloway, J. S.,
Brock, C. A., Middlebrook, A. M., Ryerson, T. B., Jimenez, J. L., Decarlo, P. F., Hecobian, A., Weber, R. J., Stickel, R., Tanner, D. J., and Huey, L. G.: Airborne cloud condensation nuclei
measurements during the 2006 Texas Air Quality Study, J. Geophys.
Res.-Atmos., 116, 1–18, https://doi.org/10.1029/2010JD014874, 2011.
Atkinson, R., Baulch, D. L., Cox, R. A., Crowley, J. N., Hampson, R. F., Hynes, R. G., Jenkin, M. E., Rossi, M. J., Troe, J., and IUPAC Subcommittee: Evaluated kinetic and photochemical data for atmospheric chemistry: Volume II – gas phase reactions of organic species, Atmos. Chem. Phys., 6, 3625–4055, https://doi.org/10.5194/acp-6-3625-2006, 2006.
Bhandari, S., Gani, S., Patel, K., Wang, D. S., Soni, P., Arub, Z., Habib, G., Apte, J. S., and Hildebrandt Ruiz, L.: Sources and atmospheric dynamics of organic aerosol in New Delhi, India: insights from receptor modeling, Atmos. Chem. Phys., 20, 735–752, https://doi.org/10.5194/acp-20-735-2020, 2020.
Bhattu, D. and Tripathi, S. N.: Inter-seasonal variability in
size-resolved CCN properties at Kanpur, India, Atmos. Environ., 85,
161–168, https://doi.org/10.1016/j.atmosenv.2013.12.016, 2014.
Bhattu, D. and Tripathi, S. N.: CCN closure study: Effects of aerosol
chemical composition and mixing state, J. Geophys Res.-Atmos., 120, 766–783, https://doi.org/10.1002/2014JD021978, 2015.
Bi, X., Zhang, G., Li, L., Wang, X., Li, M., Sheng, G., Fu, J., and Zhou, Z.:
Mixing state of biomass burning particles by single particle aerosol mass
spectrometer in the urban area of PRD, China, Atmos.
Environ., 45, 3447–3453,
https://doi.org/10.1016/j.atmosenv.2011.03.034, 2011.
Boucher, O., Randall, D., Artaxo, P., Bretherton, C., Feingold, G., Forster,
P., Kerminen, V.-M., Kondo, Y., Liao, H., Lohmann, U., Rasch, P., Satheesh, S. K., Sherwood, S., Stevens, B., and Zhang, X. Y.: Clouds and Aerosols, in: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Stocker, T. F., Qin, D., Plattner, G.-K., Tignor, M., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M., Cambridge University Press, Cambridge, UK and New York, NY, USA, 2013.
Bougiatioti, A., Fountoukis, C., Kalivitis, N., Pandis, S. N., Nenes, A., and Mihalopoulos, N.: Cloud condensation nuclei measurements in the marine boundary layer of the Eastern Mediterranean: CCN closure and droplet growth kinetics, Atmos. Chem. Phys., 9, 7053–7066, https://doi.org/10.5194/acp-9-7053-2009, 2009.
Bougiatioti, A., Nenes, A., Fountoukis, C., Kalivitis, N., Pandis, S. N., and Mihalopoulos, N.: Size-resolved CCN distributions and activation kinetics of aged continental and marine aerosol, Atmos. Chem. Phys., 11, 8791–8808, https://doi.org/10.5194/acp-11-8791-2011, 2011.
Braga, R. C., Rosenfeld, D., Weigel, R., Jurkat, T., Andreae, M. O., Wendisch, M., Pöschl, U., Voigt, C., Mahnke, C., Borrmann, S., Albrecht, R. I., Molleker, S., Vila, D. A., Machado, L. A. T., and Grulich, L.: Further evidence for CCN aerosol concentrations determining the height of warm rain and ice initiation in convective clouds over the Amazon basin, Atmos. Chem. Phys., 17, 14433–14456, https://doi.org/10.5194/acp-17-14433-2017, 2017.
Brock, C. A., Wagner, N. L., Anderson, B. E., Beyersdorf, A., Campuzano-Jost, P., Day, D. A., Diskin, G. S., Gordon, T. D., Jimenez, J. L., Lack, D. A., Liao, J., Markovic, M. Z., Middlebrook, A. M., Perring, A. E., Richardson, M. S., Schwarz, J. P., Welti, A., Ziemba, L. D., and Murphy, D. M.: Aerosol optical properties in the southeastern United States in summer – Part 2: Sensitivity of aerosol optical depth to relative humidity and aerosol parameters, Atmos. Chem. Phys., 16, 5009–5019, https://doi.org/10.5194/acp-16-5009-2016, 2016.
Chakraborty, A., Bhattu, D., Gupta, T., Tripathi, S. N., and Canagaratna,
M. R.: Real-time measurements of ambient aerosols in a polluted Indian city:
Sources, characteristics, and processing of organic aerosols during foggy
and nonfoggy periods, J. Geophys. Res.-Atmos., 120,
9006–9019, https://doi.org/10.1002/2015JD023419, 2015.
Chakraborty, A., Gupta, T., and Tripathi, S. N.: Chemical composition and
characteristics of ambient aerosols and rainwater residues during Indian
summer monsoon: Insight from aerosol mass spectrometry, Atmos.
Environ., 136, 144–155, https://doi.org/10.1016/j.atmosenv.2016.04.024,
2016.
Chen, Y., Wild, O., Wang, Y., Ran, L., Teich, M., Größ, J., Wang, L., Spindler, G., Herrmann, H., van Pinxteren, D., McFiggans, G., and Wiedensohler, A.: The influence of impactor size cut-off shift caused by
hygroscopic growth on particulate matter loading and composition
measurements, Atmos. Environ., 195, 141–148,
https://doi.org/10.1016/j.atmosenv.2018.09.049, 2018.
Cheney, J. L., Conner, W. D., Bennett, R. L., Duke, D. L., and Walters, C.
L.: Formation of a detached plume from a cement plant, NTIS, Springfield,
VA, USA, 1983.
Derwent, R. G., Ryall, D. B., Jennings, S. G., Spain, T. G., and Simmonds,
P. G.: Black carbon aerosol and carbon monoxide in European regionally
polluted air masses at Mace Head, Ireland during 1995–1998, Atmos.
Environ., 35, 6371–6378,
https://doi.org/10.1016/S1352-2310(01)00394-6, 2001.
Draxler, R. R. and Rolph, G. D.: HYSPLIT (HYbrid Single-Particle
Lagrangian Integrated Trajectory) model access via NOAA ARL READY website,
NOAA Air Resources Laboratory, Silver Spring, MD, 25, available at: http://ready.arl.noaa.gov/HYSPLIT.php (last access: 18 May 2020), 2003.
Du, H. H., Kong, L. D., Cheng, T., Chen, J., Yang, X., Zhang, R., Han, Z., Yan, Z., and Ma, Y.: Insights into ammonium particle-to-gas conversion: non-sulfate
ammonium coupling with nitrate and chloride, Aerosol Air Qual. Res., 10,
589–595, https://doi.org/10.4209/aaqr.2010.04.0034, 2010.
Dusek, U., Frank, G. P., Curtius, J., Drewnick, F., Schneider, J.,
Kürten, A., Rose, D., Andreae, M. O., Borrmann, S., and Pöschl, U.: Enhanced organic mass fraction and
decreased hygroscopicity of cloud condensation nuclei (CCN) during new
particle formation events, Geophys. Res. Lett., 37,
https://doi.org/10.1029/2009GL040930, 2010.
Engelhart, G. J., Hennigan, C. J., Miracolo, M. A., Robinson, A. L., and Pandis, S. N.: Cloud condensation nuclei activity of fresh primary and aged biomass burning aerosol, Atmos. Chem. Phys., 12, 7285–7293, https://doi.org/10.5194/acp-12-7285-2012, 2012.
Erickson, R. E., Yates, L. M., Clark, R. L., and McEwen, D.: The reaction
of sulfur dioxide with ozone in water and its possible atmospheric
significance, Atmos. Environ., 11, 813–817,
https://doi.org/10.1016/0004-6981(77)90043-9, 1977.
Ervens, B., Turpin, B. J., and Weber, R. J.: Secondary organic aerosol formation in cloud droplets and aqueous particles (aqSOA): a review of laboratory, field and model studies, Atmos. Chem. Phys., 11, 11069–11102, https://doi.org/10.5194/acp-11-11069-2011, 2011.
Esri, Garmin International: World Countries (Generalized), available at:
https://www.arcgis.com/home/item.html?id=170b5e6529064b8d9275168687880359 (last access: 17 May 2020),
2010.
Fuzzi, S., Decesari, S., Facchini, M. C., Cavalli, F., Emblico, L., Mircea,
M., Andreae, M. O., Trebs, I., Hoffer, A., Guyon, P., Artaxo, P., Rizzo, L. V., Lara, L. L., Pauliquevis, T., Maenhaut, W., Raes, N., Chi, X., Mayol-Bracero, O. L., Soto-García, L. L., Claeys, M., Kourtchev, I., Rissler, J., Swietlicki, E., Tagliavini, E., Schkolnik, G., Falkovich, A. H., Rudich, Y., Fisch, G., and Gatti, L. V.: Overview of the inorganic and organic composition
of size-segregated aerosol in Rondonia, Brazil, from the biomass-burning
period to the onset of the wet season, J. Geophys. Res.-Atmos., 112, https://doi.org/10.1029/2005JD006741, 2007.
Gandhi, H. S. and Shelef, M.: Effects of sulphur on noble metal automotive
catalysts, Appl. Catal., 77, 175–186, https://doi.org/10.1016/0166-9834(91)80063-3,
1991.
Gani, S., Bhandari, S., Seraj, S., Wang, D. S., Patel, K., Soni, P., Arub, Z., Habib, G., Hildebrandt Ruiz, L., and Apte, J. S.: Submicron aerosol composition in the world's most polluted megacity: the Delhi Aerosol Supersite study, Atmos. Chem. Phys., 19, 6843–6859, https://doi.org/10.5194/acp-19-6843-2019, 2019.
Gaur, A., Tripathi, S. N., Kanawade, V. P., Tare, V., and Shukla, S. P.:
Four-year measurements of trace gases (SO2, NOx, CO, and O3) at an urban
location, Kanpur, in Northern India, J. Atmos.
Chem., 71, 283–301, https://doi.org/10.1007/s10874-014-9295-8, 2014.
Guhathakurta, P., Rajeevan, M., Sikka, D. R., and Tyagi, A.: Observed
changes in southwest monsoon rainfall over India during 1901–2011,
Int. J. Climatol., 35, 1881–1898,
https://doi.org/10.1002/joc.4095, 2015.
Gunn, R. and Phillips, B. B.: An experimental investigation of the effect
of air pollution on the initiation of rain, J. Meteorol., 14,
272–280, https://doi.org/10.1175/1520-0469(1957)014<0272:AEIOTE>2.0.CO;2, 1957.
Gunthe, S. S., King, S. M., Rose, D., Chen, Q., Roldin, P., Farmer, D. K., Jimenez, J. L., Artaxo, P., Andreae, M. O., Martin, S. T., and Pöschl, U.: Cloud condensation nuclei in pristine tropical rainforest air of Amazonia: size-resolved measurements and modeling of atmospheric aerosol composition and CCN activity, Atmos. Chem. Phys., 9, 7551–7575, https://doi.org/10.5194/acp-9-7551-2009, 2009.
Gunthe, S. S., Rose, D., Su, H., Garland, R. M., Achtert, P., Nowak, A., Wiedensohler, A., Kuwata, M., Takegawa, N., Kondo, Y., Hu, M., Shao, M., Zhu, T., Andreae, M. O., and Pöschl, U.: Cloud condensation nuclei (CCN) from fresh and aged air pollution in the megacity region of Beijing, Atmos. Chem. Phys., 11, 11023–11039, https://doi.org/10.5194/acp-11-11023-2011, 2011.
Habib, G., Venkataraman, C., Chiapello, I., Ramachandran, S., Boucher, O.,
and Reddy, M. S.: Seasonal and interannual variability in absorbing
aerosols over India derived from TOMS: Relationship to regional meteorology
and emissions, Atmos. Environ., 40, 1909–1921,
https://doi.org/10.1016/j.atmosenv.2005.07.077, 2006.
Harrison, R. M. and Pio, C. A.: Major ion composition and chemical
associations of inorganic atmospheric aerosols, Environ. Sci.
Technol., 17, 169–174, https://doi.org/10.1021/es00109a009, 1983.
Haynes, W. M., Lide, D. R., and Bruno, T. J. (Eds.): CRC Handbook of Chemistry and Physics, 95th Edn., CRC press, Florida, USA, 2014.
Ho, K. F., Lee, S. C., Guo, H., and Tsai, W. Y.: Seasonal and diurnal
variations of volatile organic compounds (VOCs) in the atmosphere of Hong
Kong, Sci. Total Environ., 322, 155–166,
https://doi.org/10.1016/j.scitotenv.2003.10.004, 2004.
Hong, J., Häkkinen, S. A. K., Paramonov, M., Äijälä, M., Hakala, J., Nieminen, T., Mikkilä, J., Prisle, N. L., Kulmala, M., Riipinen, I., Bilde, M., Kerminen, V.-M., and Petäjä, T.: Hygroscopicity, CCN and volatility properties of submicron atmospheric aerosol in a boreal forest environment during the summer of 2010, Atmos. Chem. Phys., 14, 4733–4748, https://doi.org/10.5194/acp-14-4733-2014, 2014.
Jaiprakash, Singhai, A., Habib, G., Raman, R. S., and Gupta, T.: Chemical
characterization of PM1.0 aerosol in Delhi and source apportionment using
positive matrix factorization, Environ. Sci. Pollut.
R., 24, 445–462, https://doi.org/10.1007/s11356-016-7708-8, 2017.
Kalapureddy, M. C. R., Kaskaoutis, D. G., Ernest Raj, P., Devara, P. C. S.,
Kambezidis, H. D., Kosmopoulos, P. G., and Nastos, P. T.: Identification of
aerosol type over the Arabian Sea in the premonsoon season during the
Integrated Campaign for Aerosols, Gases and Radiation Budget
(ICARB), J. Geophys. Res.-Atmos., 114, D17203,
https://doi.org/10.1029/2009JD011826, 2009.
Kaneyasu, N., Yoshikado, H., Mizuno, T., Sakamoto, K., and Soufuku, M.:
Chemical forms and sources of extremely high nitrate and chloride in winter
aerosol pollution in the Kanto Plain of Japan, Atmos.
Environ., 33, 1745–1756,
https://doi.org/10.1016/S1352-2310(98)00396-3, 1999.
Lance, S., Raatikainen, T., Onasch, T. B., Worsnop, D. R., Yu, X.-Y., Alexander, M. L., Stolzenburg, M. R., McMurry, P. H., Smith, J. N., and Nenes, A.: Aerosol mixing state, hygroscopic growth and cloud activation efficiency during MIRAGE 2006, Atmos. Chem. Phys., 13, 5049–5062, https://doi.org/10.5194/acp-13-5049-2013, 2013.
Lee, S. Y., Gan, C., and Chew, B. N.: Visibility deterioration and
hygroscopic growth of biomass burning aerosols over a tropical coastal city:
a case study over Singapore's airport, Atmos. Sci. Lett., 17,
624–629, https://doi.org/10.1002/asl.712, 2016.
Leena, P. P., Pandithurai, G., Anilkumar, V., Murugavel, P., Sonbawne, S.
M., and Dani, K. K.: Seasonal variability in aerosol, CCN and their
relationship observed at a high altitude site in Western Ghats, Meteorol. Atmos. Phys., 128, 143–153,
https://doi.org/10.1007/s00703-015-0406-0, 2016.
Leng, C., Zhang, Q., Zhang, D., Xu, C., Cheng, T., Zhang, R., Tao, J., Chen, J., Zha, S., Zhang, Y., Li, X., Kong, L., and Gao, W.: Variations of cloud condensation nuclei (CCN) and aerosol activity during fog–haze episode: a case study from Shanghai, Atmos. Chem. Phys., 14, 12499–12512, https://doi.org/10.5194/acp-14-12499-2014, 2014.
Liu, X., Zhang, Y., Cheng, Y., Hu, M., and Han, T.: Aerosol hygroscopicity
and its impact on atmospheric visibility and radiative forcing in Guangzhou
during the 2006 PRIDE-PRD campaign, Atmos. Environ., 60, 59–67,
https://doi.org/10.1016/j.atmosenv.2012.06.016, 2012.
Moorthy, K. K., Satheesh, S. K., Babu, S. S., and Dutt, C. B. S.:
Integrated campaign for aerosols, gases and radiation budget (ICARB): an
overview, J. Earth Syst. Sci., 117, 243–262,
https://doi.org/10.1007/s12040-008-0029-7, 2008.
Nair, V. S., Moorthy, K. K., Babu, S. S., Narasimhulu, K., Reddy, L. S. S., Reddy, R. R., Gopal, K. R., Sreekanth, V., Madhavan, B. L., and Niranjan, K.: Size segregated aerosol mass
concentration measurements over the Arabian Sea during ICARB, J. Earth Syst. Sci., 117, 315–323,
https://doi.org/10.1007/s12040-008-0034-x, 2008a.
Nair, V. S., Babu, S. S., and Moorthy, K. K.: Aerosol characteristics in
the marine atmospheric boundary layer over the Bay of Bengal and Arabian Sea
during ICARB: Spatial distribution and latitudinal and longitudinal
gradients, J. Geophys. Res.-Atmos., 113, D15208,
https://doi.org/10.1029/2008JD009823, 2008b.
Nault, B. A., Campuzano-Jost, P., Day, D. A., Schroder, J. C., Anderson, B., Beyersdorf, A. J., Blake, D. R., Brune, W. H., Choi, Y., Corr, C. A., de Gouw, J. A., Dibb, J., DiGangi, J. P., Diskin, G. S., Fried, A., Huey, L. G., Kim, M. J., Knote, C. J., Lamb, K. D., Lee, T., Park, T., Pusede, S. E., Scheuer, E., Thornhill, K. L., Woo, J.-H., and Jimenez, J. L.: Secondary organic aerosol production from local emissions dominates the organic aerosol budget over Seoul, South Korea, during KORUS-AQ, Atmos. Chem. Phys., 18, 17769–17800, https://doi.org/10.5194/acp-18-17769-2018, 2018.
Nenes, A., Pandis, S. N., and Pilinis, C.: ISORROPIA: A new thermodynamic
equilibrium model for multiphase multicomponent inorganic aerosols, Aquat.
Geochem., 4, 123–152, https://doi.org/10.1023/A:1009604003981, 1998.
Ng, N. L., Canagaratna, M. R., Jimenez, J. L., Zhang, Q., Ulbrich, I. M.,
and Worsnop, D. R.: Real-time methods for estimating organic component mass
concentrations from aerosol mass spectrometer data, Environ. Sci.
Technol., 45, 910–916, https://doi.org/10.1021/es102951k, 2010.
Padró, L. T., Moore, R. H., Zhang, X., Rastogi, N., Weber, R. J., and
Nenes, A.: Mixing state and compositional effects on CCN activity and
droplet growth kinetics of size-resolved CCN in an urban environment, Atmos.
Chem. Phys., 12, 10239–10255, https://doi.org/10.5194/acp-12-10239-2012,
2012.
Pan, Y., Tian, S., Liu, D., Fang, Y., Zhu, X., Zhang, Q., Zheng, B., Michalski, G., and Wang, Y.:
Fossil fuel combustion-related emissions dominate atmospheric ammonia
sources during severe haze episodes: Evidence from 15N-stable isotope in
size-resolved aerosol ammonium, Environ. Sci.
Technol., 50, 8049–8056, https://doi.org/10.1021/acs.est.6b00634,
2016.
Petters, M. D. and Kreidenweis, S. M.: A single parameter representation of hygroscopic growth and cloud condensation nucleus activity, Atmos. Chem. Phys., 7, 1961–1971, https://doi.org/10.5194/acp-7-1961-2007, 2007.
Petters, M. D., Carrico, C. M., Kreidenweis, S. M., Prenni, A. J., DeMott,
P. J., Collett Jr., J. L., and Moosmüller, H.: Cloud condensation
nucleation activity of biomass burning aerosol, J. Geophys.
Res.-Atmos., 114, D22205, https://doi.org/10.1029/2009JD012353, 2009.
Pöschl, U., Rose, D., and Andreae, M. O.: Climatologies of
Cloud-Related Aerosols – Part 2: Particle Hygroscopicity and Cloud
Condensation Nucleus Activity, in: Clouds in the Perturbed Climate System: Their
Relationship to Energy Balance, Atmospheric Dynamics, and Precipitation,
58–72, MIT Press, Cambridge, 2009.
Pringle, K. J., Tost, H., Pozzer, A., Pöschl, U., and Lelieveld, J.: Global distribution of the effective aerosol hygroscopicity parameter for CCN activation, Atmos. Chem. Phys., 10, 5241–5255, https://doi.org/10.5194/acp-10-5241-2010, 2010.
Psichoudaki, M., Nenes, A., Florou, K., Kaltsonoudis, C., and Pandis, S.
N.: Hygroscopic properties of atmospheric particles emitted during
wintertime biomass burning episodes in Athens, Atmos. Environ., 178,
66–72, https://doi.org/10.1016/j.atmosenv.2018.01.004, 2018.
Rajput, P., Mandaria, A.,
Kachawa, L., Singh, D. K., Singh, A. K., and Gupta, T.: Wintertime
source-apportionment of PM1 from Kanpur in the Indo-Gangetic plain, Climatic
Change, 1, 503–507, 2015.
Ram, K., Tripathi, S. N., Sarin, M. M., and
Bhattu, D.: Primary and secondary aerosols from an urban site (Kanpur) in
the Indo-Gangetic Plain: impact on CCN, CN concentrations and optical
properties, Atmos. Environ., 89, 655–663,
https://doi.org/10.1016/j.atmosenv.2014.02.009, 2014.
Reddy, M. S. and Venkataraman, C.: Inventory of aerosol and sulphur
dioxide emissions from India: I – Fossil fuel combustion, Atmos.
Environ., 36, 677–697, https://doi.org/10.1016/S1352-2310(01)00463-0,
2002.
Rissler, J., Swietlicki, E., Zhou, J., Roberts, G., Andreae, M. O., Gatti, L. V., and Artaxo, P.: Physical properties of the sub-micrometer aerosol over the Amazon rain forest during the wet-to-dry season transition – comparison of modeled and measured CCN concentrations, Atmos. Chem. Phys., 4, 2119–2143, https://doi.org/10.5194/acp-4-2119-2004, 2004.
Rose, D., Nowak, A., Achtert, P., Wiedensohler, A., Hu, M., Shao, M., Zhang, Y., Andreae, M. O., and Pöschl, U.: Cloud condensation nuclei in polluted air and biomass burning smoke near the mega-city Guangzhou, China – Part 1: Size-resolved measurements and implications for the modeling of aerosol particle hygroscopicity and CCN activity, Atmos. Chem. Phys., 10, 3365–3383, https://doi.org/10.5194/acp-10-3365-2010, 2010.
Rose, D., Gunthe, S. S., Su, H., Garland, R. M., Yang, H., Berghof, M., Cheng, Y. F., Wehner, B., Achtert, P., Nowak, A., Wiedensohler, A., Takegawa, N., Kondo, Y., Hu, M., Zhang, Y., Andreae, M. O., and Pöschl, U.: Cloud condensation nuclei in polluted air and biomass burning smoke near the mega-city Guangzhou, China – Part 2: Size-resolved aerosol chemical composition, diurnal cycles, and externally mixed weakly CCN-active soot particles, Atmos. Chem. Phys., 11, 2817–2836, https://doi.org/10.5194/acp-11-2817-2011, 2011.
Rosenfeld, D.: TRMM observed first direct evidence of smoke from forest
fires inhibiting rainfall, Geophys. Res. Lett., 26, 3105–3108,
https://doi.org/10.1029/1999GL006066, 1999.
Rosenfeld, D.: Suppression of rain and snow by urban and industrial air
pollution, Science, 287, 1793–1796,
https://doi.org/10.1126/science.287.5459.1793, 2000.
Rosenfeld, D., Lahav, R., Khain, A., and Pinsky, M.: The role of sea spray
in cleansing air pollution over ocean via cloud processes,
Science, 297, 1667–1670, https://doi.org/10.1126/science.1073869, 2002.
Rosenfeld, D., Lohmann, U., Raga, G. B., O'Dowd, C. D., Kulmala, M., Fuzzi,
S., Reissell, A., and Andreae, M. O.: Flood or drought: how do aerosols affect
precipitation?, Science, 321, 1309–1313, https://doi.org/10.1126/science.1160606, 2008.
Roy, A., Chatterjee, A., Sarkar, C., Das, S. K., Ghosh, S. K., and Raha,
S.: A study on aerosol-cloud condensation nuclei (CCN) activation over
eastern Himalaya in India, Atmos. Res., 189, 69–81,
https://doi.org/10.1016/j.atmosres.2017.01.015, 2017.
Rudich, Y., Khersonsky, O., and Rosenfeld, D.: Treating clouds with a grain
of salt, Geophys. Res. Lett., 29, 2060,
https://doi.org/10.1029/2002GL016055, 2002.
Sandradewi, J., Prévôt, A. S. H., Szidat, S., Perron, N., Alfarra, M. R., Lanz, V. A., Weingartner,
E., and Baltensperger, U.: Using Aerosol Light Absorption Measurements for
the Quantitative Determination of Wood Burning and Traffic Emission Contributions to Particulate Matter, Environ. Sci. Technol., 42, 3316–3323, https://doi.org/10.1021/es702253m, 2008.
Seinfeld, J. H.: Atmospheric Chemistry and Physics of Air Pollution,
Environ. Sci. Technol., 20, 863–863,
https://doi.org/10.1021/es00151a602, 1986.
Sharma, S. K., Kumar, M., Gupta, N. C., Saxena, M., and Mandal, T. K.:
Characteristics of ambient ammonia over Delhi, India, Meteorol.
Atmos. Phys., 124, 67–82,
https://doi.org/10.1007/s00703-013-0299-8, 2014.
Squires, P.: The microstructure and colloidal stability of warm clouds: Part
II – The causes of the variations in microstructure, Tellus, 10, 262–271,
https://doi.org/10.1111/j.2153-3490.1958.tb02012.x, 1958.
Stelson, A. W. and Seinfeld, J. H.: Relative humidity and pH dependence of
the vapor pressure of ammonium nitrate-nitric acid solutions at 25 ∘C, Atmos. Environ., 16, 993–1000,
https://doi.org/10.1016/0004-6981(82)90185-8, 1982.
Sullivan, R. C., Moore, M. J. K., Petters, M. D., Kreidenweis, S. M., Roberts, G. C., and Prather, K. A.: Effect of chemical mixing state on the hygroscopicity and cloud nucleation properties of calcium mineral dust particles, Atmos. Chem. Phys., 9, 3303–3316, https://doi.org/10.5194/acp-9-3303-2009, 2009.
Tao, W. K., Chen, J. P., Li, Z., Wang, C., and Zhang, C.: Impact of
aerosols on convective clouds and precipitation, Rev.
Geophys., 50, RG2001, https://doi.org/10.1029/2011RG000369, 2012.
Tiwari, S., Dahiya, A., and Kumar, N.: Investigation into relationships
among NO, NO2, NOx, O3, and CO at an urban background site in Delhi, India,
Atmos. Res., 157, 119–126,
https://doi.org/10.1016/j.atmosres.2015.01.008, 2015.
Turšič, J., Podkrajšek, B., Grgić, I., Ctyroky, P., Berner,
A., Dusek, U., and Hitzenberger, R.: Chemical composition and hygroscopic
properties of size-segregated aerosol particles collected at the Adriatic
coast of Slovenia, Chemosphere, 63, 1193–1202,
https://doi.org/10.1016/j.chemosphere.2005.08.040, 2006.
Wang, J., Cubison, M. J., Aiken, A. C., Jimenez, J. L., and Collins, D. R.: The importance of aerosol mixing state and size-resolved composition on CCN concentration and the variation of the importance with atmospheric aging of aerosols, Atmos. Chem. Phys., 10, 7267–7283, https://doi.org/10.5194/acp-10-7267-2010, 2010.
Wang, J. and Martin, S. T.: Satellite characterization of urban aerosols:
Importance of including hygroscopicity and mixing state in the retrieval
algorithms, J. Geophys. Res.-Atmos., 112, D17203,
https://doi.org/10.1029/2006JD008078, 2007.
Wang, S., Nan, J., Shi, C., Fu, Q., Gao, S., Wang, D., Cui, H., Saiz-Lopez, A., and
Zhou, B.:
Atmospheric ammonia and its impacts on regional air quality over the
megacity of Shanghai, China, Sci. Rep.-UK, 5, 15842,
https://doi.org/10.1038/srep15842, 2015.
Wang, Y. and Chen, Y.: Significant Climate Impact of Highly Hygroscopic
Atmospheric Aerosols in Delhi, India, Geophys. Res. Lett., 46, 5535–5545,
https://doi.org/10.1029/2019GL082339, 2019.
Wu, Z. J., Poulain, L., Henning, S., Dieckmann, K., Birmili, W., Merkel, M., van Pinxteren, D., Spindler, G., Müller, K., Stratmann, F., Herrmann, H., and Wiedensohler, A.: Relating particle hygroscopicity and CCN activity to chemical composition during the HCCT-2010 field campaign, Atmos. Chem. Phys., 13, 7983–7996, https://doi.org/10.5194/acp-13-7983-2013, 2013.
Zhang, Q., Jimenez, J. L., Worsnop, D. R., and Canagaratna, M.: A case
study of urban particle acidity and its influence on secondary organic
aerosol, Environ. Sci. Technol., 41, 3213–3219,
https://doi.org/10.1021/es061812j, 2007.
Short summary
Aerosol physiochemical properties were characterized for three prominent air masses over New Delhi, a highly polluted megacity. The chemical composition and size distribution data were used to deduce the hygroscopicity parameter and cloud condensation nuclei (CCN) number concentration. The activated fraction was the highest in the world for any continental site. The aerosol physiochemical properties and their diurnal patterns were interlinked and impacted aerosol hygroscopicity and CCN activity.
Aerosol physiochemical properties were characterized for three prominent air masses over New...
Altmetrics
Final-revised paper
Preprint