Articles | Volume 23, issue 9
https://doi.org/10.5194/acp-23-5373-2023
© Author(s) 2023. 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-23-5373-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 May 2023
Research article |
| 12 May 2023
| 12 May 2023
Aerosol first indirect effect of African smoke at the cloud base of marine cumulus clouds over Ascension Island, southern Atlantic Ocean
R&D Satellite Observations, Royal Netherlands Meteorological Institute (KNMI), De Bilt, the Netherlands
Karolina Sarna
Geosciences & Remote Sensing, Delft University of Technology (TUD), Delft, the Netherlands
Jessica Brown
Meteorology and Air Quality Group, Wageningen University & Research, Wageningen, the Netherlands
Elma V. Tenner
Geosciences & Remote Sensing, Delft University of Technology (TUD), Delft, the Netherlands
Manon Schenkels
Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, the Netherlands
David P. Donovan
R&D Satellite Observations, Royal Netherlands Meteorological Institute (KNMI), De Bilt, the Netherlands
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Martin de Graaf, Maarten Sneep, Mark ter Linden, L. Gijsbert Tilstra, and J. Pepijn Veefkind
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David Patrick Donovan, Gerd-Jan van Zadelhoff, and Ping Wang
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Nicole Docter, Anja Hünerbein, David P. Donovan, Rene Preusker, Jürgen Fischer, Jan Fokke Meirink, Piet Stammes, and Michael Eisinger
Atmos. Meas. Tech., 17, 2507–2519, https://doi.org/10.5194/amt-17-2507-2024, https://doi.org/10.5194/amt-17-2507-2024, 2024
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Atmos. Meas. Tech., 16, 5953–5975, https://doi.org/10.5194/amt-16-5953-2023, https://doi.org/10.5194/amt-16-5953-2023, 2023
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David P. Donovan, Pavlos Kollias, Almudena Velázquez Blázquez, and Gerd-Jan van Zadelhoff
Atmos. Meas. Tech., 16, 5327–5356, https://doi.org/10.5194/amt-16-5327-2023, https://doi.org/10.5194/amt-16-5327-2023, 2023
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Zhipeng Qu, David P. Donovan, Howard W. Barker, Jason N. S. Cole, Mark W. Shephard, and Vincent Huijnen
Atmos. Meas. Tech., 16, 4927–4946, https://doi.org/10.5194/amt-16-4927-2023, https://doi.org/10.5194/amt-16-4927-2023, 2023
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Ulla Wandinger, Moritz Haarig, Holger Baars, David Donovan, and Gerd-Jan van Zadelhoff
Atmos. Meas. Tech., 16, 4031–4052, https://doi.org/10.5194/amt-16-4031-2023, https://doi.org/10.5194/amt-16-4031-2023, 2023
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We introduce the algorithms that have been developed to derive cloud top height and aerosol layer products from observations with the Atmospheric Lidar (ATLID) onboard the Earth Cloud, Aerosol and Radiation Explorer (EarthCARE). The products provide information on the uppermost cloud and geometrical and optical properties of aerosol layers in an atmospheric column. They can be used individually but also serve as input for algorithms that combine observations with EarthCARE’s lidar and imager.
Gerd-Jan van Zadelhoff, David P. Donovan, and Ping Wang
Atmos. Meas. Tech., 16, 3631–3651, https://doi.org/10.5194/amt-16-3631-2023, https://doi.org/10.5194/amt-16-3631-2023, 2023
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The Earth Clouds, Aerosols and Radiation (EarthCARE) satellite mission features the UV lidar ATLID. The ATLID FeatureMask algorithm provides a high-resolution detection probability mask which is used to guide smoothing strategies within the ATLID profile retrieval algorithm, one step further in the EarthCARE level-2 processing chain, in which the microphysical retrievals and target classification are performed.
Abdanour Irbah, Julien Delanoë, Gerd-Jan van Zadelhoff, David P. Donovan, Pavlos Kollias, Bernat Puigdomènech Treserras, Shannon Mason, Robin J. Hogan, and Aleksandra Tatarevic
Atmos. Meas. Tech., 16, 2795–2820, https://doi.org/10.5194/amt-16-2795-2023, https://doi.org/10.5194/amt-16-2795-2023, 2023
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Atmos. Meas. Tech., 16, 2485–2510, https://doi.org/10.5194/amt-16-2485-2023, https://doi.org/10.5194/amt-16-2485-2023, 2023
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We introduce an aerosol classification model that has been developed for the Earth Clouds, Aerosols and Radiation Explorer (EarthCARE). The model provides a consistent description of microphysical, optical, and radiative properties of common aerosol types such as dust, sea salt, pollution, and smoke. It is used for aerosol classification and assessment of radiation effects based on the synergy of active and passive observations with lidar, imager, and radiometer of the multi-instrument platform.
Konstantinos Michailidis, Maria-Elissavet Koukouli, Dimitris Balis, J. Pepijn Veefkind, Martin de Graaf, Lucia Mona, Nikolaos Papagianopoulos, Gesolmina Pappalardo, Ioanna Tsikoudi, Vassilis Amiridis, Eleni Marinou, Anna Gialitaki, Rodanthi-Elisavet Mamouri, Argyro Nisantzi, Daniele Bortoli, Maria João Costa, Vanda Salgueiro, Alexandros Papayannis, Maria Mylonaki, Lucas Alados-Arboledas, Salvatore Romano, Maria Rita Perrone, and Holger Baars
Atmos. Chem. Phys., 23, 1919–1940, https://doi.org/10.5194/acp-23-1919-2023, https://doi.org/10.5194/acp-23-1919-2023, 2023
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Comparisons with ground-based correlative lidar measurements constitute a key component in the validation of satellite aerosol products. This paper presents the validation of the TROPOMI aerosol layer height (ALH) product, using archived quality assured ground-based data from lidar stations that belong to the EARLINET network. Comparisons between the TROPOMI ALH and co-located EARLINET measurements show good agreement over the ocean.
Victor J. H. Trees, Ping Wang, Piet Stammes, Lieuwe G. Tilstra, David P. Donovan, and A. Pier Siebesma
Atmos. Meas. Tech., 15, 3121–3140, https://doi.org/10.5194/amt-15-3121-2022, https://doi.org/10.5194/amt-15-3121-2022, 2022
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Cloud shadows are observed by the TROPOMI satellite instrument as a result of its high spatial resolution. These shadows contaminate TROPOMI's air quality measurements, because shadows are generally not taken into account in the models that are used for aerosol and trace gas retrievals. We present the Detection AlgoRithm for CLOud Shadows (DARCLOS) for TROPOMI, which is the first cloud shadow detection algorithm for a satellite spectrometer.
Karolina Sarna, David P. Donovan, and Herman W. J. Russchenberg
Atmos. Meas. Tech., 14, 4959–4970, https://doi.org/10.5194/amt-14-4959-2021, https://doi.org/10.5194/amt-14-4959-2021, 2021
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We show a method for obtaining cloud optical extinction with a lidar system. We use a scheme in which a lidar signal is inverted based on the estimated value of cloud extinction at the far end of the cloud and apply a correction for multiple scattering within the cloud and a range resolution correction. By applying our technique, we show that it is possible to obtain the cloud optical extinction with an error better than 5 % up to 90 m within the cloud.
Jim M. Haywood, Steven J. Abel, Paul A. Barrett, Nicolas Bellouin, Alan Blyth, Keith N. Bower, Melissa Brooks, Ken Carslaw, Haochi Che, Hugh Coe, Michael I. Cotterell, Ian Crawford, Zhiqiang Cui, Nicholas Davies, Beth Dingley, Paul Field, Paola Formenti, Hamish Gordon, Martin de Graaf, Ross Herbert, Ben Johnson, Anthony C. Jones, Justin M. Langridge, Florent Malavelle, Daniel G. Partridge, Fanny Peers, Jens Redemann, Philip Stier, Kate Szpek, Jonathan W. Taylor, Duncan Watson-Parris, Robert Wood, Huihui Wu, and Paquita Zuidema
Atmos. Chem. Phys., 21, 1049–1084, https://doi.org/10.5194/acp-21-1049-2021, https://doi.org/10.5194/acp-21-1049-2021, 2021
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Every year, the seasonal cycle of biomass burning from agricultural practices in Africa creates a huge plume of smoke that travels many thousands of kilometres over the Atlantic Ocean. This study provides an overview of a measurement campaign called the cloud–aerosol–radiation interaction and forcing for year 2017 (CLARIFY-2017) and documents the rationale, deployment strategy, observations, and key results from the campaign which utilized the heavily equipped FAAM atmospheric research aircraft.
Cristofer Jimenez, Albert Ansmann, Ronny Engelmann, David Donovan, Aleksey Malinka, Jörg Schmidt, Patric Seifert, and Ulla Wandinger
Atmos. Chem. Phys., 20, 15247–15263, https://doi.org/10.5194/acp-20-15247-2020, https://doi.org/10.5194/acp-20-15247-2020, 2020
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A novel lidar method to study cloud microphysical properties (of liquid water clouds) and to study aerosol–cloud interaction (ACI) is developed and presented in this paper. In Part 1, the theoretical framework including an error analysis is given together with an overview of the aerosol information that the same lidar system can obtain. The ACI concept based on aerosol and cloud information is also explained. Applications of the proposed approach to lidar measurements are presented in Part 2.
Cristofer Jimenez, Albert Ansmann, Ronny Engelmann, David Donovan, Aleksey Malinka, Patric Seifert, Robert Wiesen, Martin Radenz, Zhenping Yin, Johannes Bühl, Jörg Schmidt, Boris Barja, and Ulla Wandinger
Atmos. Chem. Phys., 20, 15265–15284, https://doi.org/10.5194/acp-20-15265-2020, https://doi.org/10.5194/acp-20-15265-2020, 2020
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Part 2 presents the application of the dual-FOV polarization lidar technique introduced in Part 1. A lidar system was upgraded with a second polarization telescope, and it was deployed at the southernmost tip of South America. A comparison with alternative remote sensing techniques and the evaluation of the aerosol–cloud–wind relation in a convective boundary layer in pristine marine conditions are presented in two case studies, demonstrating the potential of the approach for ACI studies.
Maurits L. Kooreman, Piet Stammes, Victor Trees, Maarten Sneep, L. Gijsbert Tilstra, Martin de Graaf, Deborah C. Stein Zweers, Ping Wang, Olaf N. E. Tuinder, and J. Pepijn Veefkind
Atmos. Meas. Tech., 13, 6407–6426, https://doi.org/10.5194/amt-13-6407-2020, https://doi.org/10.5194/amt-13-6407-2020, 2020
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We investigated the influence of clouds on the Absorbing Aerosol Index (AAI), an indicator of the presence of small particles in the atmosphere. Clouds produce artifacts in AAI calculations on the individual measurement (7 km) scale, which was not seen with previous instruments, as well as on large (1000+ km) scales. To reduce these artefacts, we used three different AAI calculation techniques of varying complexity. We find that the AAI artifacts are reduced when using more complex techniques.
Lieuwe G. Tilstra, Martin de Graaf, Ping Wang, and Piet Stammes
Atmos. Meas. Tech., 13, 4479–4497, https://doi.org/10.5194/amt-13-4479-2020, https://doi.org/10.5194/amt-13-4479-2020, 2020
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The goal of the study was to determine the accuracy of the radiometric calibration of the TROPOMI instrument on board the Sentinel-5 Precursor satellite in flight. The Earth reflectances were compared to radiative transfer calculations. We report calibration accuracies and errors for 21 selected wavelength bands between 328 and 2314 nm, located in TROPOMI spectral bands 3–7. The reported numbers can be used to perform corrections that will benefit the retrievals of many atmospheric properties.
Swadhin Nanda, Martin de Graaf, J. Pepijn Veefkind, Maarten Sneep, Mark ter Linden, Jiyunting Sun, and Pieternel F. Levelt
Atmos. Meas. Tech., 13, 3043–3059, https://doi.org/10.5194/amt-13-3043-2020, https://doi.org/10.5194/amt-13-3043-2020, 2020
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This paper presents a first validation of the TROPOspheric Monitoring Instrument (TROPOMI) aerosol layer height (ALH) product, which is an estimate of the height of an aerosol layer using a spectrometer on board ESA's Sentinel-5 Precursor satellite mission. Comparison between the TROPOMI ALH product and co-located aerosol extinction heights from the CALIOP instrument on board NASA's CALIPSO mission show good agreement for selected cases over the ocean and large differences over land.
Martin de Graaf, Ruben Schulte, Fanny Peers, Fabien Waquet, L. Gijsbert Tilstra, and Piet Stammes
Atmos. Chem. Phys., 20, 6707–6723, https://doi.org/10.5194/acp-20-6707-2020, https://doi.org/10.5194/acp-20-6707-2020, 2020
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The radiative effect from smoke by wildfires has been found to be much stronger than models predict. The effect is complex; smoke generally cools the climate system by reflecting sunlight but strongly warms the system when it is found over a bright cloud deck. In this paper three different satellite datasets are compared and all three confirm the strong warming of African smoke over the cloud deck in the south-east Atlantic. The intercomparison reduces the uncertainties in the observations.
Debora Griffin, Christopher Sioris, Jack Chen, Nolan Dickson, Andrew Kovachik, Martin de Graaf, Swadhin Nanda, Pepijn Veefkind, Enrico Dammers, Chris A. McLinden, Paul Makar, and Ayodeji Akingunola
Atmos. Meas. Tech., 13, 1427–1445, https://doi.org/10.5194/amt-13-1427-2020, https://doi.org/10.5194/amt-13-1427-2020, 2020
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This study looks into validating the aerosol layer height product from the recently launched TROPOspheric Monitoring Instrument (TROPOMI) for forest fire plume through comparisons with two other satellite products, and interpreting differences due to the individual measurement techniques. These satellite observations are compared to predicted plume heights from Environment and Climate Change's air quality forecast model.
Swadhin Nanda, Martin de Graaf, J. Pepijn Veefkind, Mark ter Linden, Maarten Sneep, Johan de Haan, and Pieternel F. Levelt
Atmos. Meas. Tech., 12, 6619–6634, https://doi.org/10.5194/amt-12-6619-2019, https://doi.org/10.5194/amt-12-6619-2019, 2019
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This paper discusses a neural network forward model used by the operational aerosol layer height (ALH) retrieval algorithm for the TROPOspheric Monitoring Instrument (TROPOMI) on board the European Sentinel-5 Precursor satellite mission. This model replaces online radiative transfer calculations within the oxygen A-band, improving the speed of the algorithm by 3 orders of magnitude. With this advancement in the algorithm's speed, TROPOMI is set to deliver the ALH product operationally.
Martin de Graaf, L. Gijsbert Tilstra, and Piet Stammes
Atmos. Meas. Tech., 12, 5119–5135, https://doi.org/10.5194/amt-12-5119-2019, https://doi.org/10.5194/amt-12-5119-2019, 2019
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A new algorithm is described, which was used to derive direct radiative effects of aerosols above clouds. These effects are among the largest uncertainties in global climate model simulations, and observations are needed to constrain these simulations. A recently developed method was applied to a combination of satellite reflectance measurements to cover the entire shortwave (solar) spectrum. Radiative effects of aerosols over the south-east Atlantic are presented, where the effects are largest.
Swadhin Nanda, J. Pepijn Veefkind, Martin de Graaf, Maarten Sneep, Piet Stammes, Johan F. de Haan, Abram F. J. Sanders, Arnoud Apituley, Olaf Tuinder, and Pieternel F. Levelt
Atmos. Meas. Tech., 11, 3263–3280, https://doi.org/10.5194/amt-11-3263-2018, https://doi.org/10.5194/amt-11-3263-2018, 2018
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An approach to estimate the height of aerosol plumes over land from satellite measurements of the oxygen A band is proposed. The method, termed dynamic scaling, forces the retrieval to use spectral points that contain more height information. The method is tested in a synthetic environment as well as with GOME-2A and GOME-2B measurements of wildfire plumes over Europe, with very encouraging results. This method can be easily applied to other aerosol height algorithms using least squares.
Pieternel F. Levelt, Joanna Joiner, Johanna Tamminen, J. Pepijn Veefkind, Pawan K. Bhartia, Deborah C. Stein Zweers, Bryan N. Duncan, David G. Streets, Henk Eskes, Ronald van der A, Chris McLinden, Vitali Fioletov, Simon Carn, Jos de Laat, Matthew DeLand, Sergey Marchenko, Richard McPeters, Jerald Ziemke, Dejian Fu, Xiong Liu, Kenneth Pickering, Arnoud Apituley, Gonzalo González Abad, Antti Arola, Folkert Boersma, Christopher Chan Miller, Kelly Chance, Martin de Graaf, Janne Hakkarainen, Seppo Hassinen, Iolanda Ialongo, Quintus Kleipool, Nickolay Krotkov, Can Li, Lok Lamsal, Paul Newman, Caroline Nowlan, Raid Suleiman, Lieuwe Gijsbert Tilstra, Omar Torres, Huiqun Wang, and Krzysztof Wargan
Atmos. Chem. Phys., 18, 5699–5745, https://doi.org/10.5194/acp-18-5699-2018, https://doi.org/10.5194/acp-18-5699-2018, 2018
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The aim of this paper is to highlight the many successes of the Ozone Monitoring Instrument (OMI) spanning more than 13 years. Data from OMI have been used in a wide range of applications. Due to its unprecedented spatial resolution, in combination with daily global coverage, OMI plays a unique role in measuring trace gases important for the ozone layer, air quality, and climate change. OMI data continue to be used for new research and applications.
Swadhin Nanda, Martin de Graaf, Maarten Sneep, Johan F. de Haan, Piet Stammes, Abram F. J. Sanders, Olaf Tuinder, J. Pepijn Veefkind, and Pieternel F. Levelt
Atmos. Meas. Tech., 11, 161–175, https://doi.org/10.5194/amt-11-161-2018, https://doi.org/10.5194/amt-11-161-2018, 2018
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Estimating aerosol layer height in the atmosphere from satellite data in the oxygen A band (758–770 nm) over land is challenging over land, since the surface is generally very bright in this wavelength region. This paper discusses an interplay between the surface and the atmosphere in their contributions to the top-of-atmosphere reflectance spectrum and the consequent biases obtained while estimating aerosol layer height, using synthetic data and real data from the GOME-2 satellite instrument.
Stephanie P. Rusli, David P. Donovan, and Herman W. J. Russchenberg
Atmos. Meas. Tech., 10, 4777–4803, https://doi.org/10.5194/amt-10-4777-2017, https://doi.org/10.5194/amt-10-4777-2017, 2017
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A retrieval method exploiting a synergy of radar, lidar, and microwave radiometer measurements is developed to simultaneously derive microphysical properties of cloud and drizzle in a physically consistent way. After successful tests with simulated scenes, this technique is applied to data collected in Cabauw, the Netherlands. Evaluation of the results shows that the retrieved cloud and drizzle properties are consistent with what is derived from multiple independent retrieval methods.
Marco de Bruine, Arnoud Apituley, David Patrick Donovan, Hendrik Klein Baltink, and Marijn Jorrit de Haij
Atmos. Meas. Tech., 10, 1893–1909, https://doi.org/10.5194/amt-10-1893-2017, https://doi.org/10.5194/amt-10-1893-2017, 2017
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To know how air pollution moves away from their sources, we need to know the height of the pollution. We use a laser instrument that detects particles of air pollution to precisely measure the height of the particles. Now we want to detect the layer where the pollution is. As the height of this layer changes with time it is difficult to automatically follow the correct layer. Pathfinder, which works like route planners that find the shortest way, improves this task.
Holger Sihler, Peter Lübcke, Rüdiger Lang, Steffen Beirle, Martin de Graaf, Christoph Hörmann, Johannes Lampel, Marloes Penning de Vries, Julia Remmers, Ed Trollope, Yang Wang, and Thomas Wagner
Atmos. Meas. Tech., 10, 881–903, https://doi.org/10.5194/amt-10-881-2017, https://doi.org/10.5194/amt-10-881-2017, 2017
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This paper presents the independent and simple IFR method to retrieve the FOV of an instrument, i.e. the two-dimensional sensitivity distribution. IFR relies on correlated measurements featuring a higher spatial resolution and was applied to two satellite instruments, GOME-2 and OMI, and a DOAS instrument integrated in an SO2 camera. Our results confirm the commonly applied FOV distributions. IFR is applicable for verification exercises as well as degradation monitoring in the field.
Yerong Wu, Martin de Graaf, and Massimo Menenti
Atmos. Meas. Tech., 9, 5575–5589, https://doi.org/10.5194/amt-9-5575-2016, https://doi.org/10.5194/amt-9-5575-2016, 2016
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In this paper, we developed a new algorithm to improve the retrieval of aerosol optical depth (AOD) over land with satellite measurement by refining the shape of the spectral surface reflectance to improve the estimated background reflectance in the channel used for AOD retrieval. The results show that the angular effects of the retrievals are largely reduced, including fewer occurrences of negative retrievals. This implies that the users can get more accurate data without angular bias.
Martin de Graaf, Holger Sihler, Lieuwe G. Tilstra, and Piet Stammes
Atmos. Meas. Tech., 9, 3607–3618, https://doi.org/10.5194/amt-9-3607-2016, https://doi.org/10.5194/amt-9-3607-2016, 2016
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The shapes and sizes of the FoV from the OMI satellite instrument were determined with extensive lab tests but never verified after launch. Here, collocated measurements from MODIS, flying in formation, were used to find the most optimal shape of the OMI FoV. This shape is not quadrangular, as suggested by the provided corner coordinates of a pixel, but rather super-Gaussian shaped and overlapping with the FoV of neighbouring pixels.
Ulla Wandinger, Volker Freudenthaler, Holger Baars, Aldo Amodeo, Ronny Engelmann, Ina Mattis, Silke Groß, Gelsomina Pappalardo, Aldo Giunta, Giuseppe D'Amico, Anatoli Chaikovsky, Fiodor Osipenko, Alexander Slesar, Doina Nicolae, Livio Belegante, Camelia Talianu, Ilya Serikov, Holger Linné, Friedhelm Jansen, Arnoud Apituley, Keith M. Wilson, Martin de Graaf, Thomas Trickl, Helmut Giehl, Mariana Adam, Adolfo Comerón, Constantino Muñoz-Porcar, Francesc Rocadenbosch, Michaël Sicard, Sergio Tomás, Diego Lange, Dhiraj Kumar, Manuel Pujadas, Francisco Molero, Alfonso J. Fernández, Lucas Alados-Arboledas, Juan Antonio Bravo-Aranda, Francisco Navas-Guzmán, Juan Luis Guerrero-Rascado, María José Granados-Muñoz, Jana Preißler, Frank Wagner, Michael Gausa, Ivan Grigorov, Dimitar Stoyanov, Marco Iarlori, Vincenco Rizi, Nicola Spinelli, Antonella Boselli, Xuan Wang, Teresa Lo Feudo, Maria Rita Perrone, Ferdinando De Tomasi, and Pasquale Burlizzi
Atmos. Meas. Tech., 9, 1001–1023, https://doi.org/10.5194/amt-9-1001-2016, https://doi.org/10.5194/amt-9-1001-2016, 2016
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We introduce the quality-assurance efforts of the European Aerosol Research Lidar Network (EARLINET) at instrument level. Within several campaigns, 21 EARLINET systems from 18 EARLINET stations were intercompared. A comprehensive strategy for campaign setup and data evaluation was established. The intercomparisons have reinforced our confidence in the EARLINET data quality and allowed us to draw conclusions on necessary system improvements and to identify major challenges for our future work.
D. P. Donovan, H. Klein Baltink, J. S. Henzing, S. R. de Roode, and A. P. Siebesma
Atmos. Meas. Tech., 8, 237–266, https://doi.org/10.5194/amt-8-237-2015, https://doi.org/10.5194/amt-8-237-2015, 2015
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Stratocumulus clouds are important for weather and climate. They contain relatively little water but are optically thick enough to turn sunny days to grey and globally they have a strong impact on the Earth's energy budget. A new lidar (laser-radar) technique has been developed that is well suited for remotely measuring stratocumulus properties in the important cloud-based region. The technique can supply information that is difficult or impossible for other remote-sensing methods to provide.
X. J. Sun, R. W. Zhang, G. J. Marseille, A. Stoffelen, D. Donovan, L. Liu, and J. Zhao
Atmos. Meas. Tech., 7, 2695–2717, https://doi.org/10.5194/amt-7-2695-2014, https://doi.org/10.5194/amt-7-2695-2014, 2014
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Measurement report: An investigation of the spatiotemporal variability in aerosols in the mountainous terrain of the upper Colorado River basin using SAIL-Net
Contributions of the synoptic meteorology to the seasonal cloud condensation nuclei cycle over the Southern Ocean
Measurement report: Cloud condensation nuclei (CCN) activity in the South China Sea from shipborne observations during the summer and winter of 2021 – seasonal variation and anthropogenic influence
Measurement report: A comparative analysis of an intensive incursion of fluorescing African dust particles over Puerto Rico and another over Spain
Measurement report: Analysis of aerosol optical depth variation at Zhongshan Station in Antarctica
External particle mixing influences hygroscopicity in a sub-urban area
Long-term observations of black carbon and carbon monoxide in the Poker Flat Research Range, central Alaska, with a focus on forest wildfire emissions
High ice-nucleating particle concentrations associated with Arctic haze in springtime cold-air outbreaks
CCN estimations at a high-altitude remote site: role of organic aerosol variability and hygroscopicity
Aerosol hygroscopicity over the southeast Atlantic Ocean during the biomass burning season – Part 1: From the perspective of scattering enhancement
Spatial, temporal, and meteorological impact of the 26 February 2023 dust storm: increase in particulate matter concentrations across New Mexico and West Texas
Large spatiotemporal variability in aerosol properties over central Argentina during the CACTI field campaign
Quantification and characterization of primary biological aerosol particles and microbes aerosolized from Baltic seawater
Brownness of organics in anthropogenic biomass burning aerosols over South Asia
Measurement report: size-resolved particle effective density measured by the AAC-SMPS and implications for chemical composition
Source apportionment of particle number size distribution at the street canyon and urban background sites
Long-range transport of coarse mineral dust: an evaluation of the Met Office Unified Model against aircraft observations
Extreme Saharan dust events expand northward over the Atlantic and Europe, prompting record-breaking PM10 and PM2.5 episodes
Atmospheric black carbon in the metropolitan area of La Paz and El Alto, Bolivia: concentration levels and emission sources
Changing optical properties of black carbon and brown carbon aerosols during long-range transport from the Indo-Gangetic Plain to the equatorial Indian Ocean
The evolution of aerosols mixing state derived from a field campaign in Beijing: implications to the particles aging time scale in urban atmosphere
Aerosol size distribution properties associated with cold-air outbreaks in the Norwegian Arctic
Ice-nucleating particles active below −24 °C in a Finnish boreal forest and their relationship to bioaerosols
Measurement report: The influence of particle number size distribution and hygroscopicity on the microphysical properties of cloud droplets at a mountain site
Measurements of particle emissions of an A350-941 burning 100 % sustainable aviation fuels in cruise
Vertical distribution of ice nucleating particles over the boreal forest of Hyytiälä, Finland
Multi-year gradient measurements of sea spray fluxes over the Baltic Sea and the North Atlantic Ocean
Measurement report: In situ vertical profiles of below-cloud aerosol over the central Greenland Ice Sheet
Occurrence, abundance, and formation of atmospheric tarballs from a wide range of wildfires in the western US
Measurement report: Aircraft observations of aerosol and microphysical quantities of stratocumulus in autumn over Guangxi Province, China: Diurnal variation, vertical distribution and aerosol-cloud relationship
Size-resolved hygroscopicity and volatility properties of ambient urban aerosol particles measured by the VH-TDMA system in the autumn of 2023
Measurement report: Contribution of atmospheric new particle formation to ultrafine particle concentration, cloud condensation nuclei, and radiative forcing – results from 5-year observations in central Europe
Simulated contrail-processed aviation soot aerosols are poor ice-nucleating particles at cirrus temperatures
In situ vertical observations of the layered structure of air pollution in a continental high latitude urban boundary layer during winter
Measurement report: The variation properties of aerosol hygroscopic growth related to chemical composition during new particle formation days in a coastal city of southeast China
Biological and dust aerosols as sources of ice-nucleating particles in the eastern Mediterranean: source apportionment, atmospheric processing and parameterization
Quantifying the dust direct radiative effect in the southwestern United States: findings from multiyear measurements
Hygroscopic Aerosols Amplify Longwave Downward Radiation in the Arctic
How horizontal transport and turbulent mixing impact aerosol particle and precursor concentrations at a background site in the UAE
Markedly different impacts of primary emissions and secondary aerosol formation on aerosol mixing states revealed by simultaneous measurements of CCNC, H(/V)TDMA, and SP2
Measurement Report: Optical and structural properties of atmospheric water-soluble organic carbon in China: Insights from multi-site spectroscopic measurements
Aerosol spectral optical properties in the Paris urban area, and its peri−urban and forested surroundings during summer 2022 from ACROSS surface observations
Phase matrix characterization of long-range transported Saharan dust using multiwavelength polarized polar imaging nephelometry
Vertically resolved aerosol variability at the Amazon Tall Tower Observatory under wet-season conditions
Vertical structure of a springtime smoky and humid troposphere over the southeast Atlantic from aircraft and reanalysis
Terrestrial runoff is an important source of biological INPs in Arctic marine systems
Measurement Report: Long-term Assessment of Primary and Secondary Organic Aerosols in Shanghai Megacity throughout China’s Clean Air Actions since 2010
Shipborne observations of black carbon aerosols in the western Arctic Ocean during summer and autumn 2016–2020: impact of boreal fires
Attribution of aerosol particle number size distributions to main sources using an 11-year urban dataset
Contribution of fluorescent primary biological aerosol particles to low-level Arctic cloud residuals
Leah D. Gibson, Ezra J. T. Levin, Ethan Emerson, Nick Good, Anna Hodshire, Gavin McMeeking, Kate Patterson, Bryan Rainwater, Tom Ramin, and Ben Swanson
Atmos. Chem. Phys., 25, 2745–2762, https://doi.org/10.5194/acp-25-2745-2025, https://doi.org/10.5194/acp-25-2745-2025, 2025
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From fall 2021 to summer 2023, SAIL-Net, a network of six aerosol measurement nodes, was deployed in the East River watershed (Colorado, USA) to study aerosol variability across space and time in mountainous terrain. We found that aerosol variability is influenced by elevation differences, with the most representative site in the region changing seasonally, suggesting aerosol spatial variability also varies seasonally. This work offers a blueprint for future studies in other mountainous regions.
Tahereh Alinejadtabrizi, Yi Huang, Francisco Lang, Steven Siems, Michael Manton, Luis Ackermann, Melita Keywood, Ruhi Humphries, Paul Krummel, Alastair Williams, and Greg Ayers
Atmos. Chem. Phys., 25, 2631–2648, https://doi.org/10.5194/acp-25-2631-2025, https://doi.org/10.5194/acp-25-2631-2025, 2025
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Clouds over the Southern Ocean are crucial to Earth's energy balance, but understanding the factors that control them is complex. Our research examines how weather patterns affect tiny particles called cloud condensation nuclei (CCN), which influence cloud properties. Using data from Kennaook / Cape Grim, we found that winter air from Antarctica brings cleaner conditions with lower CCN, while summer patterns from Australia transport more particles. Precipitation also helps reduce CCN in winter.
Hengjia Ou, Mingfu Cai, Yongyun Zhang, Xue Ni, Baoling Liang, Qibin Sun, Shixin Mai, Cuizhi Sun, Shengzhen Zhou, Haichao Wang, Jiaren Sun, and Jun Zhao
Atmos. Chem. Phys., 25, 2495–2513, https://doi.org/10.5194/acp-25-2495-2025, https://doi.org/10.5194/acp-25-2495-2025, 2025
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Two shipborne observations in the South China Sea (SCS) in summer and winter 2021 were conducted. Our study found aerosol hygroscopicity is higher in the SCS in summer than winter, with significant influences from various terrestrial air masses. Aerosol size distribution had a stronger effect on activation ratio than aerosol hygroscopicity in summer and vice versa in winter. Our study provides valuable information to enhance our understanding of cloud condensation nuclei activities in the SCS.
Bighnaraj Sarangi, Darrel Baumgardner, Ana Isabel Calvo, Benjamin Bolaños-Rosero, Roberto Fraile, Alberto Rodríguez-Fernández, Delia Fernández-González, Carlos Blanco-Alegre, Cátia Gonçalves, Estela D. Vicente, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 25, 843–865, https://doi.org/10.5194/acp-25-843-2025, https://doi.org/10.5194/acp-25-843-2025, 2025
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Measurements of fluorescing aerosol particle properties have been made during two major African dust events, one over the island of Puerto Rico and the other over the city of León, Spain. The measurements were made with two wideband integrated bioaerosol spectrometers. A significant change in the background aerosol properties, at both locations, is observed when the dust is in the respective regions.
Lijing Chen, Lei Zhang, Yong She, Zhaoliang Zeng, Yu Zheng, Biao Tian, Wenqian Zhang, Zhaohui Liu, Huizheng Che, and Minghu Ding
Atmos. Chem. Phys., 25, 727–739, https://doi.org/10.5194/acp-25-727-2025, https://doi.org/10.5194/acp-25-727-2025, 2025
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Aerosol optical depth (AOD) at Zhongshan Station varies seasonally, with lower values in summer and higher values in winter. Winter and spring AOD increases due to reduced fine-mode particles, while summer and autumn increases are linked to particle growth. Diurnal AOD variation correlates positively with temperature but negatively with wind speed and humidity. Backward trajectories show that aerosols on high-AOD (low-AOD) days primarily originate from the ocean (interior Antarctica).
Shravan Deshmukh, Laurent Poulain, Birgit Wehner, Silvia Henning, Jean-Eudes Petit, Pauline Fombelle, Olivier Favez, Hartmut Herrmann, and Mira Pöhlker
Atmos. Chem. Phys., 25, 741–758, https://doi.org/10.5194/acp-25-741-2025, https://doi.org/10.5194/acp-25-741-2025, 2025
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Aerosol hygroscopicity has been investigated at a sub-urban site in Paris; analysis shows the sub-saturated regime's measured hygroscopicity and the chemically derived hygroscopic growth, shedding light on the large effect of external particle mixing and its influence on predicting hygroscopicity.
Takeshi Kinase, Fumikazu Taketani, Masayuki Takigawa, Chunmao Zhu, Yongwon Kim, Petr Mordovskoi, and Yugo Kanaya
Atmos. Chem. Phys., 25, 143–156, https://doi.org/10.5194/acp-25-143-2025, https://doi.org/10.5194/acp-25-143-2025, 2025
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Boreal forest wildfires in interior Alaska represent an important black carbon (BC) source for the Arctic and surrounding regions. We observed BC and carbon monoxide (CO) concentrations in the Poker Flat Research Range since 2016 and found a positive correlation between the observed BC / ∆CO ratio and fire radiative power (FRP) observed in Alaska and Canada. Our finding suggests the BC emission factor and/or inventory could be potentially improved by using FRP.
Erin N. Raif, Sarah L. Barr, Mark D. Tarn, James B. McQuaid, Martin I. Daily, Steven J. Abel, Paul A. Barrett, Keith N. Bower, Paul R. Field, Kenneth S. Carslaw, and Benjamin J. Murray
Atmos. Chem. Phys., 24, 14045–14072, https://doi.org/10.5194/acp-24-14045-2024, https://doi.org/10.5194/acp-24-14045-2024, 2024
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Ice-nucleating particles (INPs) allow ice to form in clouds at temperatures warmer than −35°C. We measured INP concentrations over the Norwegian and Barents seas in weather events where cold air is ejected from the Arctic. These concentrations were among the highest measured in the Arctic. It is likely that the INPs were transported to the Arctic from distant regions. These results show it is important to consider hemispheric-scale INP processes to understand INP concentrations in the Arctic.
Fernando Rejano, Andrea Casans, Marta Via, Juan Andrés Casquero-Vera, Sonia Castillo, Hassan Lyamani, Alberto Cazorla, Elisabeth Andrews, Daniel Pérez-Ramírez, Andrés Alastuey, Francisco Javier Gómez-Moreno, Lucas Alados-Arboledas, Francisco José Olmo, and Gloria Titos
Atmos. Chem. Phys., 24, 13865–13888, https://doi.org/10.5194/acp-24-13865-2024, https://doi.org/10.5194/acp-24-13865-2024, 2024
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This study provides valuable insights to improve cloud condensation nuclei (CCN) estimations at a high-altitude remote site which is influenced by nearby urban pollution. Understanding the factors that affect CCN estimations is essential to improve the CCN data coverage worldwide and assess aerosol–cloud interactions on a global scale. This is crucial for improving climate models, since aerosol–cloud interactions are the most important source of uncertainty in climate projections.
Lu Zhang, Michal Segal-Rozenhaimer, Haochi Che, Caroline Dang, Junying Sun, Ye Kuang, Paola Formenti, and Steven G. Howell
Atmos. Chem. Phys., 24, 13849–13864, https://doi.org/10.5194/acp-24-13849-2024, https://doi.org/10.5194/acp-24-13849-2024, 2024
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Using airborne measurements over the southeast Atlantic Ocean, we examined how much moisture aerosols take up during Africa’s biomass burning season. Our study revealed the important role of organic aerosols and introduced a predictive model for moisture uptake, accounting for organics, sulfate, and black carbon, summarizing results from various campaigns. These findings improve our understanding of aerosol–moisture interactions and their radiative effects in this climatically critical region.
Mary C. Robinson, Kaitlin Schueth, and Karin Ardon-Dryer
Atmos. Chem. Phys., 24, 13733–13750, https://doi.org/10.5194/acp-24-13733-2024, https://doi.org/10.5194/acp-24-13733-2024, 2024
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On 26 February 2023, New Mexico and West Texas were impacted by a severe dust storm. To analyze this storm, 28 meteorological stations and 19 PM2.5 and PM10 stations were used. Dust particles were in the air for 16 h, and dust storm conditions lasted for up to 120 min. Hourly PM2.5 and PM10 concentrations were up to 518 and 9983 µg m−3, respectively. For Lubbock, Texas, the maximum PM2.5 concentrations were the highest ever recorded.
Jerome D. Fast, Adam C. Varble, Fan Mei, Mikhail Pekour, Jason Tomlinson, Alla Zelenyuk, Art J. Sedlacek III, Maria Zawadowicz, and Louisa Emmons
Atmos. Chem. Phys., 24, 13477–13502, https://doi.org/10.5194/acp-24-13477-2024, https://doi.org/10.5194/acp-24-13477-2024, 2024
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Aerosol property measurements recently collected on the ground and by a research aircraft in central Argentina during the Cloud, Aerosol, and Complex Terrain Interactions (CACTI) campaign exhibit large spatial and temporal variability. These measurements coupled with coincident meteorological information provide a valuable data set needed to evaluate and improve model predictions of aerosols in a traditionally data-sparse region of South America.
Julika Zinke, Gabriel Pereira Freitas, Rachel Ann Foster, Paul Zieger, Ernst Douglas Nilsson, Piotr Markuszewski, and Matthew Edward Salter
Atmos. Chem. Phys., 24, 13413–13428, https://doi.org/10.5194/acp-24-13413-2024, https://doi.org/10.5194/acp-24-13413-2024, 2024
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Bioaerosols, which can influence climate and human health, were studied in the Baltic Sea. In May and August 2021, we used a sea spray simulation chamber during two ship-based campaigns to collect and measure these aerosols. We found that microbes were enriched in air compared to seawater. Bacterial diversity was analysed using DNA sequencing. Our methods provided consistent estimates of microbial emission fluxes, aligning with previous studies.
Chimurkar Navinya, Taveen Singh Kapoor, Gupta Anurag, Chandra Venkataraman, Harish C. Phuleria, and Rajan K. Chakrabarty
Atmos. Chem. Phys., 24, 13285–13297, https://doi.org/10.5194/acp-24-13285-2024, https://doi.org/10.5194/acp-24-13285-2024, 2024
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Brown carbon (BrC) aerosols show an order-of-magnitude variation in their light absorption strength. Our understanding of BrC from real-world biomass burning remains limited, complicating the determination of its radiative impact. Our study reports absorption properties of BrC emitted from four major biomass burning sources using field measurements in India. It develops an absorption parameterization for BrC and examines the spatial variability in BrC's absorption strength across India.
Yao Song, Jing Wei, Wenlong Zhao, Jinmei Ding, Xiangyu Pei, Fei Zhang, Zhengning Xu, Ruifang Shi, Ya Wei, Lu Zhang, Lingling Jin, and Zhibin Wang
EGUsphere, https://doi.org/10.5194/egusphere-2024-3298, https://doi.org/10.5194/egusphere-2024-3298, 2024
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This study investigates the size-resolved effective density (ρeff) of aerosol particles in Hangzhou using an AAC-SMPS. The ρeff values ranged from 1.47 to 1.63 g/cm3, increasing with particle diameter. Smaller particles showed significant diurnal density variations. The relationship between ρeff and particle diameter varies due to differences in the chemical composition of the particles. A new method to derive size-resolved chemical composition of particles from ρeff was proposed.
Sami D. Harni, Minna Aurela, Sanna Saarikoski, Jarkko V. Niemi, Harri Portin, Hanna Manninen, Ville Leinonen, Pasi Aalto, Phil K. Hopke, Tuukka Petäjä, Topi Rönkkö, and Hilkka Timonen
Atmos. Chem. Phys., 24, 12143–12160, https://doi.org/10.5194/acp-24-12143-2024, https://doi.org/10.5194/acp-24-12143-2024, 2024
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In this study, particle number size distribution data were used in a novel way in positive matrix factorization analysis to find aerosol source profiles in the area. Measurements were made in Helsinki at a street canyon and urban background sites between February 2015 and June 2019. Five different aerosol sources were identified. These sources underline the significance of traffic-related emissions in urban environments despite recent improvements in emission reduction technologies.
Natalie G. Ratcliffe, Claire L. Ryder, Nicolas Bellouin, Stephanie Woodward, Anthony Jones, Ben Johnson, Lisa-Maria Wieland, Maximilian Dollner, Josef Gasteiger, and Bernadett Weinzierl
Atmos. Chem. Phys., 24, 12161–12181, https://doi.org/10.5194/acp-24-12161-2024, https://doi.org/10.5194/acp-24-12161-2024, 2024
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Large mineral dust particles are more abundant in the atmosphere than expected and have different impacts on the environment than small particles, which are better represented in climate models. We use aircraft measurements to assess a climate model representation of large-dust transport. We find that the model underestimates the amount of large dust at all stages of transport and that fast removal of the large particles increases this underestimation with distance from the Sahara.
Sergio Rodríguez and Jessica López-Darias
Atmos. Chem. Phys., 24, 12031–12053, https://doi.org/10.5194/acp-24-12031-2024, https://doi.org/10.5194/acp-24-12031-2024, 2024
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Extreme Saharan dust events expanded northward to the Atlantic and Europe, prompting record-breaking PM10 and PM2.5 events. These episodes are caused by low-to-high dipole meteorology during hemispheric anomalies characterized by subtropical anticyclones shifting to higher latitudes, anomalous low pressures beyond the tropics and amplified Rossby waves. Extreme dust events occur in a paradoxical context of a multidecadal decrease in dust emissions, a topic that requires further investigation.
Valeria Mardoñez-Balderrama, Griša Močnik, Marco Pandolfi, Robin L. Modini, Fernando Velarde, Laura Renzi, Angela Marinoni, Jean-Luc Jaffrezo, Isabel Moreno R., Diego Aliaga, Federico Bianchi, Claudia Mohr, Martin Gysel-Beer, Patrick Ginot, Radovan Krejci, Alfred Wiedensohler, Gaëlle Uzu, Marcos Andrade, and Paolo Laj
Atmos. Chem. Phys., 24, 12055–12077, https://doi.org/10.5194/acp-24-12055-2024, https://doi.org/10.5194/acp-24-12055-2024, 2024
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Levels of black carbon (BC) are scarcely reported in the Southern Hemisphere, especially in high-altitude conditions. This study provides insight into the concentration level, variability, and optical properties of BC in La Paz and El Alto and at the Chacaltaya Global Atmosphere Watch Station. Two methods of source apportionment of absorption were tested and compared showing traffic as the main contributor to absorption in the urban area, in addition to biomass and open waste burning.
Krishnakant Budhavant, Mohanan Remani Manoj, Hari Ram Chandrika Rajendran Nair, Samuel Mwaniki Gaita, Henry Holmstrand, Abdus Salam, Ahmed Muslim, Sreedharan Krishnakumari Satheesh, and Örjan Gustafsson
Atmos. Chem. Phys., 24, 11911–11925, https://doi.org/10.5194/acp-24-11911-2024, https://doi.org/10.5194/acp-24-11911-2024, 2024
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The South Asian Pollution Experiment 2018 used access to three strategically located receptor observatories. Observational constraints revealed opposing trends in the mass absorption cross sections of black carbon (BC MAC) and brown carbon (BrC MAC) during long-range transport. Models estimating the climate effects of BC aerosols may have underestimated the ambient BC MAC over distant receptor areas, leading to discrepancies in aerosol absorption predicted by observation-constrained models.
Jieyao Liu, Fang Zhang, Jingye Ren, and Lu Chen
EGUsphere, https://doi.org/10.5194/egusphere-2024-2999, https://doi.org/10.5194/egusphere-2024-2999, 2024
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The particles mixing states and aging time scale are important for the evaluation of aerosols climate effects, but they are poorly parameterized in current models. We unravel the evolution of real-time mixing states and aging time scale of size-resolved particles based on field measurement in urban Beijing. This study provides observational basis for accurately parameterizing the aging time scale of aerosol particles in climate models.
Abigail S. Williams, Jeramy L. Dedrick, Lynn M. Russell, Florian Tornow, Israel Silber, Ann M. Fridlind, Benjamin Swanson, Paul J. DeMott, Paul Zieger, and Radovan Krejci
Atmos. Chem. Phys., 24, 11791–11805, https://doi.org/10.5194/acp-24-11791-2024, https://doi.org/10.5194/acp-24-11791-2024, 2024
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The measured aerosol size distribution modes reveal distinct properties characteristic of cold-air outbreaks in the Norwegian Arctic. We find higher sea spray number concentrations, smaller Hoppel minima, lower effective supersaturations, and accumulation-mode particle scavenging during cold-air outbreaks. These results advance our understanding of cold-air outbreak aerosol–cloud interactions in order to improve their accurate representation in models.
Franziska Vogel, Michael P. Adams, Larissa Lacher, Polly B. Foster, Grace C. E. Porter, Barbara Bertozzi, Kristina Höhler, Julia Schneider, Tobias Schorr, Nsikanabasi S. Umo, Jens Nadolny, Zoé Brasseur, Paavo Heikkilä, Erik S. Thomson, Nicole Büttner, Martin I. Daily, Romy Fösig, Alexander D. Harrison, Jorma Keskinen, Ulrike Proske, Jonathan Duplissy, Markku Kulmala, Tuukka Petäjä, Ottmar Möhler, and Benjamin J. Murray
Atmos. Chem. Phys., 24, 11737–11757, https://doi.org/10.5194/acp-24-11737-2024, https://doi.org/10.5194/acp-24-11737-2024, 2024
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Primary ice formation in clouds strongly influences their properties; hence, it is important to understand the sources of ice-nucleating particles (INPs) and their variability. We present 2 months of INP measurements in a Finnish boreal forest using a new semi-autonomous INP counting device based on gas expansion. These results show strong variability in INP concentrations, and we present a case that the INPs we observe are, at least some of the time, of biological origin.
Xiaojing Shen, Quan Liu, Junying Sun, Wanlin Kong, Qianli Ma, Bing Qi, Lujie Han, Yangmei Zhang, Linlin Liang, Lei Liu, Shuo Liu, Xinyao Hu, Jiayuan Lu, Aoyuan Yu, Huizheng Che, and Xiaoye Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2024-2850, https://doi.org/10.5194/egusphere-2024-2850, 2024
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In this work, an automatic switched inlet system was developed and employed to investigate the aerosols and cloud droplets at a mountain site with frequent cloud processes. It showed different characteristics of cloud residual and interstitial particles. Stronger particle hygroscopicity reduced liquid water content and smaller cloud droplet diameters. This investigation contributes to understanding aerosol-cloud interactions by assessing the impact of aerosol particles on cloud microphysics.
Rebecca Dischl, Daniel Sauer, Christiane Voigt, Theresa Harlaß, Felicitas Sakellariou, Raphael Märkl, Ulrich Schumann, Monika Scheibe, Stefan Kaufmann, Anke Roiger, Andreas Dörnbrack, Charles Renard, Maxime Gauthier, Peter Swann, Paul Madden, Darren Luff, Mark Johnson, Denise Ahrens, Reetu Sallinen, Tobias Schripp, Georg Eckel, Uwe Bauder, and Patrick Le Clercq
Atmos. Chem. Phys., 24, 11255–11273, https://doi.org/10.5194/acp-24-11255-2024, https://doi.org/10.5194/acp-24-11255-2024, 2024
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In-flight measurements of aircraft emissions burning 100 % sustainable aviation fuel (SAF) show reduced particle number concentrations up to 41 % compared to conventional jet fuel. Particle emissions are dependent on engine power setting, flight altitude, and fuel composition. Engine models show a good correlation with measurement results. Future increased prevalence of SAF can positively influence the climate impact of aviation.
Zoé Brasseur, Julia Schneider, Janne Lampilahti, Ville Vakkari, Victoria A. Sinclair, Christina J. Williamson, Carlton Xavier, Dmitri Moisseev, Markus Hartmann, Pyry Poutanen, Markus Lampimäki, Markku Kulmala, Tuukka Petäjä, Katrianne Lehtipalo, Erik S. Thomson, Kristina Höhler, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 24, 11305–11332, https://doi.org/10.5194/acp-24-11305-2024, https://doi.org/10.5194/acp-24-11305-2024, 2024
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Ice-nucleating particles (INPs) strongly influence the formation of clouds by initiating the formation of ice crystals. However, very little is known about the vertical distribution of INPs in the atmosphere. Here, we present aircraft measurements of INP concentrations above the Finnish boreal forest. Results show that near-surface INPs are efficiently transported and mixed within the boundary layer and occasionally reach the free troposphere.
Piotr Markuszewski, E. Douglas Nilsson, Julika Zinke, E. Monica Mårtensson, Matthew Salter, Przemysław Makuch, Małgorzata Kitowska, Iwona Niedźwiecka-Wróbel, Violetta Drozdowska, Dominik Lis, Tomasz Petelski, Luca Ferrero, and Jacek Piskozub
Atmos. Chem. Phys., 24, 11227–11253, https://doi.org/10.5194/acp-24-11227-2024, https://doi.org/10.5194/acp-24-11227-2024, 2024
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Our research provides new insights into the study of sea spray aerosol (SSA) emissions in the Baltic Sea and North Atlantic. We observed that SSA flux is suppressed during increased marine biological activity in the Baltic Sea. At the same time, the influence of wave age showed higher SSA emissions in the Baltic Sea for younger waves compared to the Atlantic Ocean. These insights underscore the complex interplay between biological activity and physical dynamics in regulating SSA emissions.
Heather Guy, Andrew S. Martin, Erik Olson, Ian M. Brooks, and Ryan R. Neely III
Atmos. Chem. Phys., 24, 11103–11114, https://doi.org/10.5194/acp-24-11103-2024, https://doi.org/10.5194/acp-24-11103-2024, 2024
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Aerosol particles impact cloud properties which influence Greenland Ice Sheet melt. Understanding the aerosol population that interacts with clouds is important for constraining future melt. Measurements of aerosols at cloud height over Greenland are rare, and surface measurements are often used to investigate cloud–aerosol interactions. We use a tethered balloon to measure aerosols up to cloud base and show that surface measurements are often not equivalent to those just below the cloud.
Kouji Adachi, Jack E. Dibb, Joseph M. Katich, Joshua P. Schwarz, Hongyu Guo, Pedro Campuzano-Jost, Jose L. Jimenez, Jeff Peischl, Christopher D. Holmes, and James Crawford
Atmos. Chem. Phys., 24, 10985–11004, https://doi.org/10.5194/acp-24-10985-2024, https://doi.org/10.5194/acp-24-10985-2024, 2024
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We examined aerosol particles from wildfires and identified tarballs (TBs) from the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) campaign. This study reveals the compositions, abundance, sizes, and mixing states of TBs and shows that TBs formed as the smoke aged for up to 5 h. This study provides measurements of TBs from various biomass-burning events and ages, enhancing our knowledge of TB emissions and our understanding of their climate impact.
Sihan Liu, Honglei Wang, Delong Zhao, Wei Zhou, Yuanmou Du, Zhengguo Zhang, Peng Cheng, Tianliang Zhao, Yue Ke, Zihao Wu, and Mengyu Huang
EGUsphere, https://doi.org/10.5194/egusphere-2024-2756, https://doi.org/10.5194/egusphere-2024-2756, 2024
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To understand the effect of aerosols on the vertical distribution of stratocumulus microphysical quantities in southwest China, the daily variation characteristics and formation mechanism of the vertical profiles of stratocumulus microphysical characteristics in this region were described by using the data of 9 cloud-crossing aircraft observations over Guangxi from October 10 to November 3, 2020.
Aoyuan Yu, Xiaojing Shen, Qianli Ma, Jiayuan Lu, Xinyao Hu, Yangmei Zhang, Quan Liu, Linlin Liang, Lei Liu, Shuo Liu, Hongfei Tong, Huizheng Che, Xiaoye Zhang, and Junying Sun
EGUsphere, https://doi.org/10.5194/egusphere-2024-2232, https://doi.org/10.5194/egusphere-2024-2232, 2024
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In this work, we utilized the VH-TDMA system to investigate the hygroscopicity and volatility, as well as the hygroscopicity after heated of submicron aerosols in urban Beijing during the autumn of 2023 for the first time. We analyzed the size-resolved characteristics of hygroscopicity and volatility, the relationship between hygroscopic and volatile properties, as well as the hygroscopicity of heated submicron aerosols.
Jia Sun, Markus Hermann, Kay Weinhold, Maik Merkel, Wolfram Birmili, Yifan Yang, Thomas Tuch, Harald Flentje, Björn Briel, Ludwig Ries, Cedric Couret, Michael Elsasser, Ralf Sohmer, Klaus Wirtz, Frank Meinhardt, Maik Schütze, Olaf Bath, Bryan Hellack, Veli-Matti Kerminen, Markku Kulmala, Nan Ma, and Alfred Wiedensohler
Atmos. Chem. Phys., 24, 10667–10687, https://doi.org/10.5194/acp-24-10667-2024, https://doi.org/10.5194/acp-24-10667-2024, 2024
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We investigated the characteristics of new particle formation (NPF) for various environments from urban background to high Alpine and the impacts of NPF on cloud condensation nuclei and aerosol radiative forcing. NPF features differ between site categories, implying the crucial role of local environmental factors such as the degree of emissions and meteorological conditions. The results also underscore the importance of local environments when assessing the impact of NPF on climate in models.
Baptiste Testa, Lukas Durdina, Jacinta Edebeli, Curdin Spirig, and Zamin A. Kanji
Atmos. Chem. Phys., 24, 10409–10424, https://doi.org/10.5194/acp-24-10409-2024, https://doi.org/10.5194/acp-24-10409-2024, 2024
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Aviation soot residuals released from contrails can become compacted upon sublimation of the ice crystals, generating new voids in the aggregates where ice nucleation can occur. Here we show that contrail-processed soot is highly compact but that it remains unable to form ice at a relative humidity different from that required for the formation of background cirrus from the more ubiquitous aqueous solution droplets, suggesting that it will not perturb cirrus cloud formation via ice nucleation.
Roman Pohorsky, Andrea Baccarini, Natalie Brett, Brice Barret, Slimane Bekki, Gianluca Pappaccogli, Elsa Dieudonné, Brice Temime-Roussel, Barbara D'Anna, Meeta Cesler-Maloney, Antonio Donateo, Stefano Decesari, Kathy S. Law, William R. Simpson, Javier Fochesatto, Steve R. Arnold, and Julia Schmale
EGUsphere, https://doi.org/10.5194/egusphere-2024-2863, https://doi.org/10.5194/egusphere-2024-2863, 2024
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This study presents an analysis of vertical measurements of pollution in an Alaskan city during winter. It investigates the relationship between the atmospheric structure and the layering of aerosols and trace gases. Results indicate an overall very shallow surface mixing layer. The height of this layer is strongly influenced by a local shallow wind. The study also provides information on the pollution chemical composition at different altitudes, including pollution signatures from power plants.
Lingjun Li, Mengren Li, Xiaolong Fan, Yuping Chen, Ziyi Lin, Anqi Hou, Siqing Zhang, Ronghua Zheng, and Jinsheng Chen
EGUsphere, https://doi.org/10.5194/egusphere-2024-2376, https://doi.org/10.5194/egusphere-2024-2376, 2024
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Aerosol hygroscopicity has a great impact on regional and global climate, air quality. Here, we show differences and variations in f(RH) between NPF and Non-NPF days and the effect of aerosol chemical compositions on f(RH) in Xiamen, the coastal city of southeast China by in situ observations. The findings are helpful for the further understanding about aerosol hygroscopicity in the coastal city, and the use of hygroscopic growth factors in the models of air quality and climate change.
Kunfeng Gao, Franziska Vogel, Romanos Foskinis, Stergios Vratolis, Maria I. Gini, Konstantinos Granakis, Anne-Claire Billault-Roux, Paraskevi Georgakaki, Olga Zografou, Prodromos Fetfatzis, Alexis Berne, Alexandros Papayannis, Konstantinos Eleftheridadis, Ottmar Möhler, and Athanasios Nenes
Atmos. Chem. Phys., 24, 9939–9974, https://doi.org/10.5194/acp-24-9939-2024, https://doi.org/10.5194/acp-24-9939-2024, 2024
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Ice nucleating particle (INP) concentrations are required for correct predictions of clouds and precipitation in a changing climate, but they are poorly constrained in climate models. We unravel source contributions to INPs in the eastern Mediterranean and find that biological particles are important, regardless of their origin. The parameterizations developed exhibit superior performance and enable models to consider biological-particle effects on INPs.
Alexandra Kuwano, Amato T. Evan, Blake Walkowiak, and Robert Frouin
Atmos. Chem. Phys., 24, 9843–9868, https://doi.org/10.5194/acp-24-9843-2024, https://doi.org/10.5194/acp-24-9843-2024, 2024
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The dust direct radiative effect is highly uncertain. Here we used new measurements collected over 3 years and during dust storms at a field site in a desert region in the southwestern United States to estimate the regional dust direct radiative effect. We also used novel soil mineralogy retrieved from an airborne spectrometer to estimate this parameter with model output. We find that, in this region, dust has a minimal net cooling effect on this region's climate.
Denghui Ji, Mathias Palm, Matthias Buschmann, Kerstin Ebell, Marion Maturilli, Xiaoyu Sun, and Justus Notholt
EGUsphere, https://doi.org/10.5194/egusphere-2024-2241, https://doi.org/10.5194/egusphere-2024-2241, 2024
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Our study explores how certain aerosols, like sea salt, affect infrared heat radiation in the Arctic, potentially speeding up warming. We used advanced technology to measure aerosol composition and found that these particles grow with humidity, significantly increasing their heat-trapping effect in the infrared region, especially in winter. Our findings suggest these aerosols could be a key factor in Arctic warming, emphasizing the importance of understanding aerosols for climate prediction.
Jutta Kesti, Ewan J. O'Connor, Anne Hirsikko, John Backman, Maria Filioglou, Anu-Maija Sundström, Juha Tonttila, Heikki Lihavainen, Hannele Korhonen, and Eija Asmi
Atmos. Chem. Phys., 24, 9369–9386, https://doi.org/10.5194/acp-24-9369-2024, https://doi.org/10.5194/acp-24-9369-2024, 2024
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The study combines aerosol particle measurements at the surface and vertical profiling of the atmosphere with a scanning Doppler lidar to investigate how particle transportation together with boundary layer evolution can affect particle and SO2 concentrations at the surface in the Arabian Peninsula region. The instrumentation enabled us to see elevated nucleation mode particle and SO2 concentrations at the surface when air masses transported from polluted areas are mixed in the boundary layer.
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.
Haibiao Chen, Caiqing Yan, Liubin Huang, Lin Du, Yang Yue, Xinfeng Wang, Qingcai Chen, Mingjie Xie, Junwen Liu, Fengwen Wang, Shuhong Fang, Qiaoyun Yang, Hongya Niu, Mei Zheng, Yan Wu, and Likun Xue
EGUsphere, https://doi.org/10.5194/egusphere-2024-2416, https://doi.org/10.5194/egusphere-2024-2416, 2024
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A comprehensive understanding of the optical properties of brown carbon (BrC) is essential to accurately assess its climatic effects. Based on multi-site spectroscopic measurements, this study demonstrated the significant spatial heterogeneity in the optical and structural properties of water-soluble BrC (WS-BrC) in different regions of China, and revealed factors affecting WS-BrC light absorption and the relationship between fluorophores and light absorption of WS-BrC.
Ludovico Di Antonio, Claudia Di Biagio, Paola Formenti, Aline Gratien, Vincent Michoud, Christopher Cantrell, Astrid Bauville, Antonin Bergé, Mathieu Cazaunau, Servanne Chevaillier, Manuela Cirtog, Patrice Coll, Barbara D'Anna, Joel F. de Brito, David O. De Haan, Juliette R. Dignum, Shravan Deshmukh, Olivier Favez, Pierre-Marie Flaud, Cecile Gaimoz, Lelia N. Hawkins, Julien Kammer, Brigitte Language, Franck Maisonneuve, Griša Močnik, Emilie Perraudin, Jean-Eudes Petit, Prodip Acharja, Laurent Poulain, Pauline Pouyes, Eva Drew Pronovost, Véronique Riffault, Kanuri I. Roundtree, Marwa Shahin, Guillaume Siour, Eric Villenave, Pascal Zapf, Gilles Foret, Jean-François Doussin, and Matthias Beekmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-2299, https://doi.org/10.5194/egusphere-2024-2299, 2024
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The spectral complex refractive index (CRI) and single scattering albedo were retrieved from submicron aerosol measurements at three sites within the greater Paris area during the ACROSS field campaign (June–July 2022). Measurements revealed the urban emission impact on the surrounding areas. The CRI full period averages at 520 nm were 1.41–0.037i (urban), 1.52–0.038i (peri-urban), 1.50−0.025i (rural). Organic aerosols dominated the aerosol mass and contributed up to 22% of absorption at 370 nm.
Elena Bazo, Daniel Perez-Ramirez, Antonio Valenzuela, Vanderlei Martins, Gloria Titos, Alberto Cazorla, Fernando Rejano, Diego Patrón, Arlett Diaz-Zurita, Francisco Jose Garcia-Izquierdo, David Fuertes, Lucas Alados-Arboledas, and Francisco Jose Olmo
EGUsphere, https://doi.org/10.5194/egusphere-2024-2080, https://doi.org/10.5194/egusphere-2024-2080, 2024
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This works analyses aerosol scattering phase function for transported Saharan dust to the city of Granada – located in southwestern Europe. We use the novel technique polar imaging nephelometry that helps to determine the phase functions using a CCD camara. The capability of measuring with polarized light helps to inferr new properties about the mixture of Saharan dust particles with other of anthropogenic origin.
Marco A. Franco, Rafael Valiati, Bruna A. Holanda, Bruno B. Meller, Leslie A. Kremper, Luciana V. Rizzo, Samara Carbone, Fernando G. Morais, Janaína P. Nascimento, Meinrat O. Andreae, Micael A. Cecchini, Luiz A. T. Machado, Milena Ponczek, Ulrich Pöschl, David Walter, Christopher Pöhlker, and Paulo Artaxo
Atmos. Chem. Phys., 24, 8751–8770, https://doi.org/10.5194/acp-24-8751-2024, https://doi.org/10.5194/acp-24-8751-2024, 2024
Short summary
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The Amazon wet-season atmosphere was studied at the Amazon Tall Tower Observatory site, revealing vertical variations (between 60 and 325 m) in natural aerosols. Daytime mixing contrasted with nighttime stratification, with distinct rain-induced changes in aerosol populations. Notably, optical property recovery at higher levels was faster, while near-canopy aerosols showed higher scattering efficiency. These findings enhance our understanding of aerosol impacts on climate dynamics.
Kristina Pistone, Eric M. Wilcox, Paquita Zuidema, Marco Giordano, James Podolske, Samuel E. LeBlanc, Meloë Kacenelenbogen, Steven G. Howell, and Steffen Freitag
Atmos. Chem. Phys., 24, 7983–8005, https://doi.org/10.5194/acp-24-7983-2024, https://doi.org/10.5194/acp-24-7983-2024, 2024
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The springtime southeast Atlantic atmosphere contains lots of smoke from continental fires. This smoke travels with water vapor; more smoke means more humidity. We use aircraft observations and models to describe how the values change through the season and over the region. We sort the atmosphere into different types by vertical structure and amount of smoke and humidity. Since our work shows how frequently these components coincide, it helps to better quantify heating effects over this region.
Corina Wieber, Lasse Z. Jensen, Leendert Vergeynst, Lorenz Maire, Thomas Juul-Pedersen, Kai Finster, and Tina Šantl-Temkiv
EGUsphere, https://doi.org/10.5194/egusphere-2024-1633, https://doi.org/10.5194/egusphere-2024-1633, 2024
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The Arctic region is subjected to profound changes due to the warming climate. Ice nucleating particles (INPs) in the seawater can get transported to the atmosphere and impact cloud formation. However, the sources of characteristics of INPs in the marine areas are poorly understood. We investigated the INPs in seawater from Greenlandic fjords and identified a seasonal variability and highly active INPs originating from terrestrial sources.
Haifeng Yu, Yunhua Chang, Lin Cheng, Yusen Duan, and Jianlin Hu
EGUsphere, https://doi.org/10.5194/egusphere-2024-1488, https://doi.org/10.5194/egusphere-2024-1488, 2024
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This study presents long-term measurements and comprehensive analysis of carbonaceous aerosols in PM2.5 in Shanghai. We further estimated POC and SOC levels, examining their temporal variations on interannual, monthly, seasonal, and diurnal scales. Through rigorous statistical analysis and correlation studies with meteorological parameters and pollutant concentrations, the origins, formation mechanisms, and spatial distribution patterns of SOC were elucidated.
Yange Deng, Hiroshi Tanimoto, Kohei Ikeda, Sohiko Kameyama, Sachiko Okamoto, Jinyoung Jung, Young Jun Yoon, Eun Jin Yang, and Sung-Ho Kang
Atmos. Chem. Phys., 24, 6339–6357, https://doi.org/10.5194/acp-24-6339-2024, https://doi.org/10.5194/acp-24-6339-2024, 2024
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Black carbon (BC) aerosols play important roles in Arctic climate change, yet they are not well understood because of limited observational data. We observed BC mass concentrations (mBC) in the western Arctic Ocean during summer and early autumn 2016–2020. The mean mBC in 2019 was much higher than in other years. Biomass burning was likely the dominant BC source. Boreal fire BC transport occurring near the surface and/or in the mid-troposphere contributed to high-BC events in the Arctic Ocean.
Máté Vörösmarty, Philip K. Hopke, and Imre Salma
Atmos. Chem. Phys., 24, 5695–5712, https://doi.org/10.5194/acp-24-5695-2024, https://doi.org/10.5194/acp-24-5695-2024, 2024
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The World Health Organization identified ultrafine particles, which make up most of the particle number concentrations, as a potential risk factor for humans. The sources of particle numbers are very different from those of the particulate matter mass. We performed source apportionment of size-segregated particle number concentrations over the diameter range of 6–1000 nm in Budapest for 11 full years. Six source types were identified, characterized and quantified.
Gabriel Pereira Freitas, Ben Kopec, Kouji Adachi, Radovan Krejci, Dominic Heslin-Rees, Karl Espen Yttri, Alun Hubbard, Jeffrey M. Welker, and Paul Zieger
Atmos. Chem. Phys., 24, 5479–5494, https://doi.org/10.5194/acp-24-5479-2024, https://doi.org/10.5194/acp-24-5479-2024, 2024
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Bioaerosols can participate in ice formation within clouds. In the Arctic, where global warming manifests most, they may become more important as their sources prevail for longer periods of the year. We have directly measured bioaerosols within clouds for a full year at an Arctic mountain site using a novel combination of cloud particle sampling and single-particle techniques. We show that bioaerosols act as cloud seeds and may influence the presence of ice within clouds.
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Short summary
Clouds over the oceans reflect sunlight and cool the earth. Simultaneous measurements were performed of cloud droplet sizes and smoke particles in and near the cloud base over Ascension Island, a remote island in the Atlantic Ocean, to determine the sensitivity of cloud droplets to smoke from the African continent. The smoke was found to reduce cloud droplet sizes, which makes the cloud droplets more susceptible to evaporation, reducing cloud lifetime.
Clouds over the oceans reflect sunlight and cool the earth. Simultaneous measurements were...
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