Articles | Volume 19, issue 24
https://doi.org/10.5194/acp-19-15583-2019
© Author(s) 2019. 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-19-15583-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Technical note
| 
19 Dec 2019
Technical note |
| 19 Dec 2019
| 19 Dec 2019
Technical note: A simple method for retrieval of dust aerosol optical depth with polarized reflectance over oceans
Wenbo Sun
CORRESPONDING AUTHOR
Science Systems and Applications Inc, Hampton, Virginia 23666, USA
Kyung Hee University, Yongin-shi, Kyungki-do 17104, Korea
Yongxiang Hu
NASA Langley Research Center, Hampton, Virginia 23681, USA
Rosemary R. Baize
NASA Langley Research Center, Hampton, Virginia 23681, USA
Gorden Videen
Kyung Hee University, Yongin-shi, Kyungki-do 17104, Korea
US Army Research Lab, Adelphi, Maryland 20783, USA
Sungsoo S. Kim
Kyung Hee University, Yongin-shi, Kyungki-do 17104, Korea
Young-Jun Choi
Korea Astronomy and Space Science Institute, Yuseong-gu, Daejeon
34055, Korea
Kyungin Kang
Korea Advanced Institute of Science and Technology, Daejeon 34141,
Korea
Chae Kyung Sim
Kyung Hee University, Yongin-shi, Kyungki-do 17104, Korea
Minsup Jeong
Korea Astronomy and Space Science Institute, Yuseong-gu, Daejeon
34055, Korea
Ali Omar
NASA Langley Research Center, Hampton, Virginia 23681, USA
Snorre A. Stamnes
NASA Langley Research Center, Hampton, Virginia 23681, USA
David G. MacDonnell
NASA Langley Research Center, Hampton, Virginia 23681, USA
Evgenij Zubko
Kyung Hee University, Yongin-shi, Kyungki-do 17104, Korea
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Meng Gao, Peng-Wang Zhai, Bryan A. Franz, Yongxiang Hu, Kirk Knobelspiesse, P. Jeremy Werdell, Amir Ibrahim, Brian Cairns, and Alison Chase
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Shan Zeng, Mark Vaughan, Zhaoyan Liu, Charles Trepte, Jayanta Kar, Ali Omar, David Winker, Patricia Lucker, Yongxiang Hu, Brian Getzewich, and Melody Avery
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Meloë S. Kacenelenbogen, Mark A. Vaughan, Jens Redemann, Stuart A. Young, Zhaoyan Liu, Yongxiang Hu, Ali H. Omar, Samuel LeBlanc, Yohei Shinozuka, John Livingston, Qin Zhang, and Kathleen A. Powell
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Zhaoyan Liu, Jayanta Kar, Shan Zeng, Jason Tackett, Mark Vaughan, Melody Avery, Jacques Pelon, Brian Getzewich, Kam-Pui Lee, Brian Magill, Ali Omar, Patricia Lucker, Charles Trepte, and David Winker
Atmos. Meas. Tech., 12, 703–734, https://doi.org/10.5194/amt-12-703-2019, https://doi.org/10.5194/amt-12-703-2019, 2019
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Mark Vaughan, Anne Garnier, Damien Josset, Melody Avery, Kam-Pui Lee, Zhaoyan Liu, William Hunt, Jacques Pelon, Yongxiang Hu, Sharon Burton, Johnathan Hair, Jason L. Tackett, Brian Getzewich, Jayanta Kar, and Sharon Rodier
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Man-Hae Kim, Ali H. Omar, Jason L. Tackett, Mark A. Vaughan, David M. Winker, Charles R. Trepte, Yongxiang Hu, Zhaoyan Liu, Lamont R. Poole, Michael C. Pitts, Jayanta Kar, and Brian E. Magill
Atmos. Meas. Tech., 11, 6107–6135, https://doi.org/10.5194/amt-11-6107-2018, https://doi.org/10.5194/amt-11-6107-2018, 2018
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Bin Zhao, Jonathan H. Jiang, David J. Diner, Hui Su, Yu Gu, Kuo-Nan Liou, Zhe Jiang, Lei Huang, Yoshi Takano, Xuehua Fan, and Ali H. Omar
Atmos. Chem. Phys., 18, 11247–11260, https://doi.org/10.5194/acp-18-11247-2018, https://doi.org/10.5194/acp-18-11247-2018, 2018
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We combine satellite-borne and ground-based observations to investigate the intra-annual variations of regional aerosol column loading, vertical distribution, and particle types. Column aerosol optical depth (AOD), as well as AOD > 800 m, peaks in summer/spring. However, AOD < 800 m and surface PM2.5 concentrations mostly peak in winter. The aerosol intra-annual variations differ significantly according to aerosol types characterized by different sizes, light absorption, and emission sources.
Xiaomei Lu, Yongxiang Hu, Yuekui Yang, Mark Vaughan, Zhaoyan Liu, Sharon Rodier, William Hunt, Kathy Powell, Patricia Lucker, and Charles Trepte
Atmos. Meas. Tech., 11, 3281–3296, https://doi.org/10.5194/amt-11-3281-2018, https://doi.org/10.5194/amt-11-3281-2018, 2018
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Jayanta Kar, Mark A. Vaughan, Kam-Pui Lee, Jason L. Tackett, Melody A. Avery, Anne Garnier, Brian J. Getzewich, William H. Hunt, Damien Josset, Zhaoyan Liu, Patricia L. Lucker, Brian Magill, Ali H. Omar, Jacques Pelon, Raymond R. Rogers, Travis D. Toth, Charles R. Trepte, Jean-Paul Vernier, David M. Winker, and Stuart A. Young
Atmos. Meas. Tech., 11, 1459–1479, https://doi.org/10.5194/amt-11-1459-2018, https://doi.org/10.5194/amt-11-1459-2018, 2018
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We present the motivation for and the implementation of the version 4.1 nighttime 532 nm parallel-channel calibration of the CALIOP lidar. The accuracy of calibration is significantly improved by raising the molecular normalization altitude from 30–34 km to 36–39 km to substantially reduce stratospheric aerosol contamination. The new calibration procedure eliminates biases in earlier versions and leads to an improved representation of stratospheric aerosols.
Sharon P. Burton, Eduard Chemyakin, Xu Liu, Kirk Knobelspiesse, Snorre Stamnes, Patricia Sawamura, Richard H. Moore, Chris A. Hostetler, and Richard A. Ferrare
Atmos. Meas. Tech., 9, 5555–5574, https://doi.org/10.5194/amt-9-5555-2016, https://doi.org/10.5194/amt-9-5555-2016, 2016
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Retrievals of aerosol microphysics exist for ground-based, airborne, and future space-borne lidar measurements. We investigate the information content of a lidar measurement system, using only a forward model but no explicit inversion. The simplified aerosol used here is applicable as a best case for all retrievals in the absence of additional constraints. We report (1) information content of the measurements; (2) uncertainties on the retrieved parameters; and (3) sources of compensating errors.
W. Sun, R. R. Baize, G. Videen, Y. Hu, and Q. Fu
Atmos. Chem. Phys., 15, 11909–11918, https://doi.org/10.5194/acp-15-11909-2015, https://doi.org/10.5194/acp-15-11909-2015, 2015
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A method is reported for retrieving super-thin cloud optical depth with polarized light. It is found that near-backscatter p-polarized light is sensitive to clouds, but not to ocean conditions. Near-backscatter p-polarized intensity linearly relates to super-thin cloud optical depth. Based on these findings, super-thin cloud optical depth can be retrieved with little effect from surface reflection.
W. Sun, R. R. Baize, C. Lukashin, and Y. Hu
Atmos. Chem. Phys., 15, 7725–7734, https://doi.org/10.5194/acp-15-7725-2015, https://doi.org/10.5194/acp-15-7725-2015, 2015
Z. Liu, D. Winker, A. Omar, M. Vaughan, J. Kar, C. Trepte, Y. Hu, and G. Schuster
Atmos. Chem. Phys., 15, 1265–1288, https://doi.org/10.5194/acp-15-1265-2015, https://doi.org/10.5194/acp-15-1265-2015, 2015
S. Zeng, J. Riedi, C. R. Trepte, D. M. Winker, and Y.-X. Hu
Atmos. Chem. Phys., 14, 7125–7134, https://doi.org/10.5194/acp-14-7125-2014, https://doi.org/10.5194/acp-14-7125-2014, 2014
W. Sun and C. Lukashin
Atmos. Chem. Phys., 13, 10303–10324, https://doi.org/10.5194/acp-13-10303-2013, https://doi.org/10.5194/acp-13-10303-2013, 2013
S. Rodier, Y. Hu, and M. Vaughan
The Cryosphere Discuss., https://doi.org/10.5194/tcd-7-4681-2013, https://doi.org/10.5194/tcd-7-4681-2013, 2013
Revised manuscript has not been submitted
S. P. Burton, R. A. Ferrare, M. A. Vaughan, A. H. Omar, R. R. Rogers, C. A. Hostetler, and J. W. Hair
Atmos. Meas. Tech., 6, 1397–1412, https://doi.org/10.5194/amt-6-1397-2013, https://doi.org/10.5194/amt-6-1397-2013, 2013
J. Wang, S. Park, J. Zeng, C. Ge, K. Yang, S. Carn, N. Krotkov, and A. H. Omar
Atmos. Chem. Phys., 13, 1895–1912, https://doi.org/10.5194/acp-13-1895-2013, https://doi.org/10.5194/acp-13-1895-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Remote Sensing | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Invisible aerosol layers: improved lidar detection capabilities by means of laser-induced aerosol fluorescence
Characterization of aerosol optical depth (AOD) anomalies in September and October 2022 over Skukuza in South Africa
Technical note: Evolution of convective boundary layer height estimated by Ka-band continuous millimeter wave radar at Wuhan in central China
Discussion of the spectral slope of the lidar ratio between 355 nm and 1064 nm from multiwavelength Raman lidar observations
Fluorescence properties of long-range-transported smoke: insights from five-channel lidar observations over Moscow during the 2023 wildfire season
Lidar estimates of birch pollen number, mass, and CCN-related concentrations
Distinct effects of fine and coarse aerosols on microphysical processes of shallow-precipitation systems in summer over southern China
Increased number concentrations of small particles explain perceived stagnation in air quality over Korea
Atmospheric processing and aerosol aging responsible for observed increase in absorptivity of long-range transported smoke over the southeast Atlantic
Remote-sensing detectability of airborne Arctic dust
Fluorescence spectra of atmospheric aerosols
Analysis of a saline dust storm from the Aralkum Desert – Part 1: Consistency of multisensor satellite aerosol products
The role of refractive indices in measuring mineral dust with high-spectral-resolution infrared satellite sounders: application to the Gobi Desert
Retrieval of microphysical properties of dust aerosols from extinction, backscattering and depolarization lidar measurements using various particle scattering models
Influence of covariance of aerosol and meteorology on co-located precipitating and non-precipitating clouds over the Indo-Gangetic Plain
Light-absorbing black carbon and brown carbon components of smoke aerosol from DSCOVR EPIC measurements over North America and central Africa
Observational Constraints Suggest a Smaller Effective Radiative Forcing from Aerosol-Cloud Interactions
The emission, transport, and impacts of the extreme Saharan dust storm of 2015
California wildfire smoke contributes to a positive atmospheric temperature anomaly over the western United States
Dust storms from the Taklamakan Desert significantly darken snow surface on surrounding mountains
Opposite effects of aerosols and meteorological parameters on warm clouds in two contrasting regions over eastern China
Effect of wind speed on marine aerosol optical properties over remote oceans with use of spaceborne lidar observations
Assessment of smoke plume height products derived from multisource satellite observations using lidar-derived height metrics for wildfires in the western US
A remote sensing algorithm for vertically resolved cloud condensation nuclei number concentrations from airborne and spaceborne lidar observations
Opinion: Aerosol remote sensing over the next 20 years
Monitoring biomass burning aerosol transport using CALIOP observations and reanalysis models: a Canadian wildfire event in 2019
Thermal infrared observations of a western United States biomass burning aerosol plume
A new look into the impacts of dust radiative effects on the energetics of tropical easterly waves
Wind-driven emissions of coarse-mode particles in an urban environment
Measurement report: Dust and anthropogenic aerosols' vertical distributions over northern China dense aerosols gathered at the top of the mixing layer
Climatological assessment of the vertically resolved optical and microphysical aerosol properties by lidar measurements, sun photometer, and in situ observations over 17 years at Universitat Politècnica de Catalunya (UPC) Barcelona
Aerosol optical depth climatology from the high-resolution MAIAC product over Europe: differences between major European cities and their surrounding environments
Impact of assimilating NOAA VIIRS aerosol optical depth (AOD) observations on global AOD analysis from the Copernicus Atmosphere Monitoring Service (CAMS)
Spectral dependence of birch and pine pollen optical properties using a synergy of lidar instruments
Validation activities of Aeolus wind products on the southeastern Iberian Peninsula
Thermal infrared dust optical depth and coarse-mode effective diameter over oceans retrieved from collocated MODIS and CALIOP observations
A comprehensive reappraisal of long-term aerosol characteristics, trends, and variability in Asia
Satellite (GOSAT-2 CAI-2) retrieval and surface (ARFINET) observations of aerosol black carbon over India
Spatiotemporal variation characteristics of global fires and their emissions
The (mis)identification of high-latitude dust events using remote sensing methods in the Yukon, Canada: a sub-daily variability analysis
Comparison of dust optical depth from multi-sensor products and MONARCH (Multiscale Online Non-hydrostatic AtmospheRe CHemistry) dust reanalysis over North Africa, the Middle East, and Europe
Understanding day–night differences in dust aerosols over the dust belt of North Africa, the Middle East, and Asia
Satellite observations of smoke–cloud–radiation interactions over the Amazon rainforest
Single-scattering properties of ellipsoidal dust aerosols constrained by measured dust shape distributions
Validation of the TROPOMI/S5P aerosol layer height using EARLINET lidars
Vertical characterization of fine and coarse dust particles during an intense Saharan dust outbreak over the Iberian Peninsula in springtime 2021
Aerosol optical depth regime over megacities of the world
South American 2020 regional smoke plume: intercomparison with previous years, impact on solar radiation, and the role of Pantanal biomass burning season
Circular polarization in atmospheric aerosols
Spatiotemporal continuous estimates of daily 1 km PM2.5 from 2000 to present under the Tracking Air Pollution in China (TAP) framework
Benedikt Gast, Cristofer Jimenez, Albert Ansmann, Moritz Haarig, Ronny Engelmann, Felix Fritzsch, Athena A. Floutsi, Hannes Griesche, Kevin Ohneiser, Julian Hofer, Martin Radenz, Holger Baars, Patric Seifert, and Ulla Wandinger
Atmos. Chem. Phys., 25, 3995–4011, https://doi.org/10.5194/acp-25-3995-2025, https://doi.org/10.5194/acp-25-3995-2025, 2025
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In this study, we discuss the enhanced detection capabilities of a fluorescence lidar in the case of optically thin aerosol layers in the upper troposphere and lower stratosphere (UTLS) region. Our results suggest that such thin aerosol layers are not so rare in the UTLS and can potentially trigger and impact cirrus cloud formation through heterogeneous ice nucleation. By altering the microphysical cloud properties, this could affect clouds' evolution and lifetime and thus their climate effect.
Marion Ranaivombola, Nelson Bègue, Lucas Vaz Peres, Farahnaz Fazel-Rastgar, Venkataraman Sivakumar, Gisèle Krysztofiak, Gwenaël Berthet, Fabrice Jegou, Stuart Piketh, and Hassan Bencherif
Atmos. Chem. Phys., 25, 3519–3540, https://doi.org/10.5194/acp-25-3519-2025, https://doi.org/10.5194/acp-25-3519-2025, 2025
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From September to October 2022, the Biomass Burning Aerosol Campaign (BiBAC) in Kruger National Park revealed a significant aerosol loading linked to biomass burning activity, with southeastward transport over southern Africa and the southwestern Indian Ocean (SWIO) basin. The study revealed a predominance of biomass burning aerosols and two distinct transport mechanisms of aerosol plumes and CO, underscoring the importance of east-coast observations in understanding atmospheric dynamics.
Zirui Zhang, Kaiming Huang, Fan Yi, Wei Cheng, Fuchao Liu, Jian Zhang, and Yue Jia
Atmos. Chem. Phys., 25, 3347–3361, https://doi.org/10.5194/acp-25-3347-2025, https://doi.org/10.5194/acp-25-3347-2025, 2025
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The height of the convective boundary layer (CBLH) is related to our health due to its crucial role in pollutant dispersion. The variance of vertical velocity from millimeter wave cloud radar (MMCR) can accurately capture the diurnal evolution of the CBLH, due to a small blind range and less impact by the residual layer. The CBLH is affected by radiation, humidity, cloud, and precipitation; thus, the MMCR is suitable for monitoring the CBLH, owing to its observation capability in various weather conditions.
Moritz Haarig, Ronny Engelmann, Holger Baars, Benedikt Gast, Dietrich Althausen, and Albert Ansmann
EGUsphere, https://doi.org/10.5194/egusphere-2025-449, https://doi.org/10.5194/egusphere-2025-449, 2025
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The lidar ratio is an important quantity in aerosol typing. Its spectral slope contains further information about source region or transport paths of the observed aerosol. The extension until 1064 nm is a recent development led by our institute. We gathered previous observations and add new ones to provide the spectral slope for the most important aerosol types such as marine and continental aerosol, dust, smoke and sulfate and compared it the assumptions used for spaceborne backscatter lidars.
Igor Veselovskii, Mikhail Korenskiy, Nikita Kasianik, Boris Barchunov, Qiaoyun Hu, Philippe Goloub, and Thierry Podvin
Atmos. Chem. Phys., 25, 1603–1615, https://doi.org/10.5194/acp-25-1603-2025, https://doi.org/10.5194/acp-25-1603-2025, 2025
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A fluorescence lidar was used to study transported Canadian smoke in May–September 2023. The fluorescence measurements were taken at five wavelengths. The results revealed that fluorescence capacity increases with altitude, suggesting a higher concentration of organic compounds in the upper troposphere and lower stratosphere than in the lower troposphere. The fluorescence spectra peaked in the 513 and 560 nm channels in smoke layers but decreased with wavelength in urban aerosols.
Maria Filioglou, Petri Tiitta, Xiaoxia Shang, Ari Leskinen, Pasi Ahola, Sanna Pätsi, Annika Saarto, Ville Vakkari, Uula Isopahkala, and Mika Komppula
Atmos. Chem. Phys., 25, 1639–1657, https://doi.org/10.5194/acp-25-1639-2025, https://doi.org/10.5194/acp-25-1639-2025, 2025
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Every year a vast number of people experience allergic reactions due to exposure to airborne pollen. These symptoms are concentration dependent; thus accurate information about the pollen load in the atmosphere is essential. Moreover, pollen grains and fragments of it are likely to contribute to cloud processes and suppress precipitation. Here, we estimate the concentration and cloud-relevant parameters of birch pollen in the atmosphere using observations from a PollyXT and a CL61 ceilometer.
Fengjiao Chen, Yuanjian Yang, Lu Yu, Yang Li, Weiguang Liu, Yan Liu, and Simone Lolli
Atmos. Chem. Phys., 25, 1587–1601, https://doi.org/10.5194/acp-25-1587-2025, https://doi.org/10.5194/acp-25-1587-2025, 2025
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The microphysical mechanisms of precipitation responsible for the varied impacts of aerosol particles on shallow precipitation remain unclear. This study reveals that coarse aerosol particles invigorate shallow rainfall through enhanced coalescence processes, whereas fine aerosol particles suppress shallow rainfall through intensified microphysical breaks. These impacts are independent of thermodynamic environments but are more significant in low-humidity conditions.
Sohee Joo, Juseon Shin, Matthias Tesche, Naghmeh Dehkhoda, Taegyeong Kim, and Youngmin Noh
Atmos. Chem. Phys., 25, 1023–1036, https://doi.org/10.5194/acp-25-1023-2025, https://doi.org/10.5194/acp-25-1023-2025, 2025
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In our study, we investigated why, in northeast Asia, visibility has not improved even though air pollution levels have decreased. By examining trends in Seoul and Ulsan, we found that the particles in the air are getting smaller, which scatters light more effectively and reduces how far we can see. Our findings suggest that changes in particle properties adversely affected public perception of air quality improvement even though the PM2.5 mass concentration is continuously decreasing.
Abdulamid A. Fakoya, Jens Redemann, Pablo E. Saide, Lan Gao, Logan T. Mitchell, Calvin Howes, Amie Dobracki, Ian Chang, Gonzalo A. Ferrada, Kristina Pistone, Samuel E. Leblanc, Michal Segal-Rozenhaimer, Arthur J. Sedlacek III, Thomas Eck, Brent Holben, Pawan Gupta, Elena Lind, Paquita Zuidema, Gregory Carmichael, and Connor J. Flynn
EGUsphere, https://doi.org/10.5194/egusphere-2024-3197, https://doi.org/10.5194/egusphere-2024-3197, 2025
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Tiny atmospheric particles from wildfire smoke impact climate by interacting with sunlight and clouds, the extent of which is uncertain due to gaps in understanding how smoke changes over time. We developed a new method using remote sensing instruments to track how these particles evolve during atmospheric transport. Our results show that the ability of these particles to absorb sunlight increased as they travel. This discovery could help improve predictions of future climate scenarios.
Norman T. O'Neill, Keyvan Ranjbar, Liviu Ivănescu, Yann Blanchard, Seyed Ali Sayedain, and Yasmin AboEl-Fetouh
Atmos. Chem. Phys., 25, 27–44, https://doi.org/10.5194/acp-25-27-2025, https://doi.org/10.5194/acp-25-27-2025, 2025
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Dust from mid-latitude deserts or from local drainage basins is a weak component of atmospheric aerosols in the Arctic. Satellite-based dust estimates are often overestimated because dust and cloud measurements can be confused. Illustrations are given with an emphasis on the flawed claim that a classic indicator of dust (negative brightness temperature differences) is proof of the presence of airborne Arctic dust. Low-altitude warm-water plumes are the likely source of such negative values.
Jens Reichardt, Felix Lauermann, and Oliver Behrendt
EGUsphere, https://doi.org/10.5194/egusphere-2024-3928, https://doi.org/10.5194/egusphere-2024-3928, 2024
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Optical remote sensing systems, so-called lidars, are used to learn more about aerosols, which play an important role in atmospheric processes. The present study demonstrates that lidars, which measure the backscattering behavior of aerosols over the entire visible wavelength range, can increase our knowledge of the spatial and temporal occurrence of aerosol layers, the type of aerosol and their interaction with clouds. The focus of the publication is on wildfire aerosol and Saharan dust.
Xin Xi, Jun Wang, Zhendong Lu, Andrew Sayer, Jaehwa Lee, Robert Levy, Yujie Wang, Alexei Lyapustin, Hongqing Liu, Istvan Laszlo, Changwoo Ahn, Omar Torres, Sabur Abdullaev, and Ralph Kahn
EGUsphere, https://doi.org/10.5194/egusphere-2024-3416, https://doi.org/10.5194/egusphere-2024-3416, 2024
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Currently there are a number of satellite aerosol products available for dust research. The consistency between them is generally poor understood. This paper reveals significant inconsistency between different satellite sensors and techniques in observing the wind-blown saline dust from the Aralkum Desert, and demonstrates the potential of a multisensor approach for robust characterization of airborne dust over desert areas.
Perla Alalam, Fabrice Ducos, and Hervé Herbin
Atmos. Chem. Phys., 24, 12277–12294, https://doi.org/10.5194/acp-24-12277-2024, https://doi.org/10.5194/acp-24-12277-2024, 2024
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This study dives into the impact of mineral dust laboratory complex refractive indices (CRIs) on quantifying the dust microphysical properties using satellite infrared remote sensing. Results show that using CRIs obtained by advanced realistic techniques can improve the accuracy of these measurements, emphasizing the importance of choosing the suitable CRI in atmospheric models. This improvement is crucial for better predicting the dust radiative effect and impact on the climate.
Yuyang Chang, Qiaoyun Hu, Philippe Goloub, Thierry Podvin, Igor Veselovskii, Fabrice Ducos, Gaël Dubois, Masanori Saito, Anton Lopatin, Oleg Dubovik, and Cheng Chen
EGUsphere, https://doi.org/10.5194/egusphere-2024-2655, https://doi.org/10.5194/egusphere-2024-2655, 2024
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Our study retrieved dust aerosol microphysical properties from lidar measurements using different scattering models. Numeric simulations and real data applications revealed the importance of considering depolarization measurements and particle non-sphericity to improve retrieval accuracy. Contrasts of the non-spherical scattering models in simulating particle backscattering properties, particularly the depolarization ratio, enlarge the difference of retrievals derived using these models.
Nabia Gulistan, Khan Alam, and Yangang Liu
Atmos. Chem. Phys., 24, 11333–11349, https://doi.org/10.5194/acp-24-11333-2024, https://doi.org/10.5194/acp-24-11333-2024, 2024
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This study looks at the influence of aerosol and meteorology on precipitating and non-precipitating clouds over the Indo-Gangetic Plain (IGP). A major finding of this study was that the high loading of aerosols led to a high occurrence of precipitating clouds under unstable conditions in summer. The study has the potential to open a new avenue for the scientific community to further explore and understand the complications of aerosol–cloud–precipitation over the complex topography of the IGP.
Myungje Choi, Alexei Lyapustin, Gregory L. Schuster, Sujung Go, Yujie Wang, Sergey Korkin, Ralph Kahn, Jeffrey S. Reid, Edward J. Hyer, Thomas F. Eck, Mian Chin, David J. Diner, Olga Kalashnikova, Oleg Dubovik, Jhoon Kim, and Hans Moosmüller
Atmos. Chem. Phys., 24, 10543–10565, https://doi.org/10.5194/acp-24-10543-2024, https://doi.org/10.5194/acp-24-10543-2024, 2024
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This paper introduces a retrieval algorithm to estimate two key absorbing components in smoke (black carbon and brown carbon) using DSCOVR EPIC measurements. Our analysis reveals distinct smoke properties, including spectral absorption, layer height, and black carbon and brown carbon, over North America and central Africa. The retrieved smoke properties offer valuable observational constraints for modeling radiative forcing and informing health-related studies.
Chanyoung Park, Brian J. Soden, Ryan J. Kramer, Tristan S. L’Ecuyer, and Haozhe He
EGUsphere, https://doi.org/10.5194/egusphere-2024-2547, https://doi.org/10.5194/egusphere-2024-2547, 2024
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This study addresses the challenge of quantifying the impact of aerosol-cloud interactions. By analyzing satellite data and reanalysis, we examine cloud responses to aerosols by incorporating aerosol-to-cloud droplet activation rates. Our "perfect-model" validation reveals a smaller, less uncertain impact of aerosol-cloud interactions than previously estimated. This breakthrough suggests a reduced role of aerosol-cloud interactions in determining climate sensitivity.
Brian Harr, Bing Pu, and Qinjian Jin
Atmos. Chem. Phys., 24, 8625–8651, https://doi.org/10.5194/acp-24-8625-2024, https://doi.org/10.5194/acp-24-8625-2024, 2024
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We found that the formation of the extreme trans-Atlantic African dust event in June 2015 was associated with a brief surge in dust emissions over western North Africa and extreme circulation patterns, including intensified easterly jets, which facilitated the westward transport of dust. The dust plume modified radiative flux along its transport pathway but had minor impacts on air quality in the US due to the record-high Caribbean low-level jet advecting part of the plume to the Pacific.
James L. Gomez, Robert J. Allen, and King-Fai Li
Atmos. Chem. Phys., 24, 6937–6963, https://doi.org/10.5194/acp-24-6937-2024, https://doi.org/10.5194/acp-24-6937-2024, 2024
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Wildfires in California (CA) have grown very large during the past 20 years. These fires emit sunlight-absorbing aerosols. Analyzing observational data, our study finds that aerosols emitted from large fires in northern CA spread throughout CA and Nevada and heat the atmosphere. This heating is consistent with larger-than-normal temperatures and dry conditions. Further study is needed to determine how much the aerosols heat the atmosphere and whether they are drying the atmosphere as well.
Yuxuan Xing, Yang Chen, Shirui Yan, Xiaoyi Cao, Yong Zhou, Xueying Zhang, Tenglong Shi, Xiaoying Niu, Dongyou Wu, Jiecan Cui, Yue Zhou, Xin Wang, and Wei Pu
Atmos. Chem. Phys., 24, 5199–5219, https://doi.org/10.5194/acp-24-5199-2024, https://doi.org/10.5194/acp-24-5199-2024, 2024
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This study investigated the impact of dust storms from the Taklamakan Desert on surrounding high mountains and regional radiation balance. Using satellite data and simulations, researchers found that dust storms significantly darken the snow surface in the Tien Shan, Kunlun, and Qilian mountains, reaching mountains up to 1000 km away. This darkening occurs not only in spring but also during summer and autumn, leading to increased absorption of solar radiation.
Yuqin Liu, Tao Lin, Jiahua Zhang, Fu Wang, Yiyi Huang, Xian Wu, Hong Ye, Guoqin Zhang, Xin Cao, and Gerrit de Leeuw
Atmos. Chem. Phys., 24, 4651–4673, https://doi.org/10.5194/acp-24-4651-2024, https://doi.org/10.5194/acp-24-4651-2024, 2024
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A new method, the geographical detector method (GDM), has been applied to satellite data, in addition to commonly used statistical methods, to study the sensitivity of cloud properties to aerosol over China. Different constraints for aerosol and cloud liquid water path apply over polluted and clean areas. The GDM shows that cloud parameters are more sensitive to combinations of parameters than to individual parameters, but confounding effects due to co-variation of parameters cannot be excluded.
Kangwen Sun, Guangyao Dai, Songhua Wu, Oliver Reitebuch, Holger Baars, Jiqiao Liu, and Suping Zhang
Atmos. Chem. Phys., 24, 4389–4409, https://doi.org/10.5194/acp-24-4389-2024, https://doi.org/10.5194/acp-24-4389-2024, 2024
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This paper investigates the correlation between marine aerosol optical properties and wind speeds over remote oceans using the spaceborne lidars ALADIN and CALIOP. Three remote ocean areas are selected. Pure marine aerosol optical properties at 355 nm are derived from ALADIN. The relationships between marine aerosol optical properties and wind speeds are analyzed within and above the marine atmospheric boundary layer, revealing the effect of wind speed on marine aerosols over remote oceans.
Jingting Huang, S. Marcela Loría-Salazar, Min Deng, Jaehwa Lee, and Heather A. Holmes
Atmos. Chem. Phys., 24, 3673–3698, https://doi.org/10.5194/acp-24-3673-2024, https://doi.org/10.5194/acp-24-3673-2024, 2024
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Increased wildfire intensity has resulted in taller wildfire smoke plumes. We investigate the vertical structure of wildfire smoke plumes using aircraft lidar data and establish two effective smoke plume height metrics. Four novel satellite-based plume height products are evaluated for wildfires in the western US. Our results provide guidance on the strengths and limitations of these satellite products and set the stage for improved plume rise estimates by leveraging satellite products.
Piyushkumar N. Patel, Jonathan H. Jiang, Ritesh Gautam, Harish Gadhavi, Olga Kalashnikova, Michael J. Garay, Lan Gao, Feng Xu, and Ali Omar
Atmos. Chem. Phys., 24, 2861–2883, https://doi.org/10.5194/acp-24-2861-2024, https://doi.org/10.5194/acp-24-2861-2024, 2024
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Global measurements of cloud condensation nuclei (CCN) are essential for understanding aerosol–cloud interactions and predicting climate change. To address this gap, we introduced a remote sensing algorithm that retrieves vertically resolved CCN number concentrations from airborne and spaceborne lidar systems. This innovation offers a global distribution of CCN concentrations from space, facilitating model evaluation and precise quantification of aerosol climate forcing.
Lorraine A. Remer, Robert C. Levy, and J. Vanderlei Martins
Atmos. Chem. Phys., 24, 2113–2127, https://doi.org/10.5194/acp-24-2113-2024, https://doi.org/10.5194/acp-24-2113-2024, 2024
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Aerosols are small liquid or solid particles suspended in the atmosphere, including smoke, particulate pollution, dust, and sea salt. Today, we rely on satellites viewing Earth's atmosphere to learn about these particles. Here, we speculate on the future to imagine how satellite viewing of aerosols will change. We expect more public and private satellites with greater capabilities, better ways to infer information from satellites, and merging of data with models.
Xiaoxia Shang, Antti Lipponen, Maria Filioglou, Anu-Maija Sundström, Mark Parrington, Virginie Buchard, Anton S. Darmenov, Ellsworth J. Welton, Eleni Marinou, Vassilis Amiridis, Michael Sicard, Alejandro Rodríguez-Gómez, Mika Komppula, and Tero Mielonen
Atmos. Chem. Phys., 24, 1329–1344, https://doi.org/10.5194/acp-24-1329-2024, https://doi.org/10.5194/acp-24-1329-2024, 2024
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In June 2019, smoke particles from a Canadian wildfire event were transported to Europe. The long-range-transported smoke plumes were monitored with a spaceborne lidar and reanalysis models. Based on the aerosol mass concentrations estimated from the observations, the reanalysis models had difficulties in reproducing the amount and location of the smoke aerosols during the transport event. Consequently, more spaceborne lidar missions are needed for reliable monitoring of aerosol plumes.
Blake T. Sorenson, Jeffrey S. Reid, Jianglong Zhang, Robert E. Holz, William L. Smith Sr., and Amanda Gumber
Atmos. Chem. Phys., 24, 1231–1248, https://doi.org/10.5194/acp-24-1231-2024, https://doi.org/10.5194/acp-24-1231-2024, 2024
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Smoke particles are typically submicron in size and assumed to have negligible impacts at the thermal infrared spectrum. However, we show that infrared signatures can be observed over dense smoke plumes from satellites. We found that giant particles are unlikely to be the dominant cause. Rather, co-transported water vapor injected to the middle to upper troposphere and surface cooling beneath the plume due to shadowing are significant, with the surface cooling effect being the most dominant.
Farnaz Hosseinpour and Eric M. Wilcox
Atmos. Chem. Phys., 24, 707–724, https://doi.org/10.5194/acp-24-707-2024, https://doi.org/10.5194/acp-24-707-2024, 2024
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This study shows mechanistic relationships between the radiative effect of dust aerosols in the Saharan air layer and the kinetic energy of the African easterly waves across the tropical Atlantic Ocean using 22 years of daily satellite observations and reanalysis data based on satellite assimilation. Our findings suggest that dust aerosols not merely are transported by these waves but also contribute to the growth of waves through the enhancement of diabatic heating induced by dust.
Markus D. Petters, Tyas Pujiastuti, Ajmal Rasheeda Satheesh, Sabin Kasparoglu, Bethany Sutherland, and Nicholas Meskhidze
Atmos. Chem. Phys., 24, 745–762, https://doi.org/10.5194/acp-24-745-2024, https://doi.org/10.5194/acp-24-745-2024, 2024
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This work introduces a new method that uses remote sensing techniques to obtain surface number emissions of particles with a diameter greater than 500 nm. The technique was applied to study particle emissions at an urban site near Houston, TX, USA. The emissions followed a diurnal pattern and peaked near noon local time. The daily averaged emissions correlated with wind speed. The source is likely due to wind-driven erosion of material situated on asphalted and other hard surfaces.
Zhuang Wang, Chune Shi, Hao Zhang, Yujia Chen, Xiyuan Chi, Congzi Xia, Suyao Wang, Yizhi Zhu, Kaidi Zhang, Xintong Chen, Chengzhi Xing, and Cheng Liu
Atmos. Chem. Phys., 23, 14271–14292, https://doi.org/10.5194/acp-23-14271-2023, https://doi.org/10.5194/acp-23-14271-2023, 2023
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The annual cycle of dust and anthropogenic aerosols' vertical distributions was revealed by polarization Raman lidar in Beijing. Anthropogenic aerosols typically accumulate at the top of the mixing layer (ML) due to the hygroscopic growth of atmospheric particles, and this is most significant in summer. There is no significant relationship between bottom dust mass concentration and ML height, while the dust in the upper air tends to be distributed near the mixing layer.
Simone Lolli, Michaël Sicard, Francesco Amato, Adolfo Comeron, Cristina Gíl-Diaz, Tony C. Landi, Constantino Munoz-Porcar, Daniel Oliveira, Federico Dios Otin, Francesc Rocadenbosch, Alejandro Rodriguez-Gomez, Andrés Alastuey, Xavier Querol, and Cristina Reche
Atmos. Chem. Phys., 23, 12887–12906, https://doi.org/10.5194/acp-23-12887-2023, https://doi.org/10.5194/acp-23-12887-2023, 2023
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We evaluated the long-term trends and seasonal variability of the vertically resolved aerosol properties over the past 17 years in Barcelona. Results shows that air quality is improved, with a consistent drop in PM concentrations at the surface, as well as the column aerosol optical depth. The results also show that natural dust outbreaks are more likely in summer, with aerosols reaching an altitude of 5 km, while in winter, aerosols decay as an exponential with a scale height of 600 m.
Ludovico Di Antonio, Claudia Di Biagio, Gilles Foret, Paola Formenti, Guillaume Siour, Jean-François Doussin, and Matthias Beekmann
Atmos. Chem. Phys., 23, 12455–12475, https://doi.org/10.5194/acp-23-12455-2023, https://doi.org/10.5194/acp-23-12455-2023, 2023
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Long-term (2000–2021) 1 km resolution satellite data have been used to investigate the climatological aerosol optical depth (AOD) variability and trends at different scales in Europe. Average enhancements of the local-to-regional AOD ratio at 550 nm of 57 %, 55 %, 39 % and 32 % are found for large metropolitan areas such as Barcelona, Lisbon, Paris and Athens, respectively, suggesting a non-negligible enhancement of the aerosol burden through local emissions.
Sebastien Garrigues, Melanie Ades, Samuel Remy, Johannes Flemming, Zak Kipling, Istvan Laszlo, Mark Parrington, Antje Inness, Roberto Ribas, Luke Jones, Richard Engelen, and Vincent-Henri Peuch
Atmos. Chem. Phys., 23, 10473–10487, https://doi.org/10.5194/acp-23-10473-2023, https://doi.org/10.5194/acp-23-10473-2023, 2023
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The Copernicus Atmosphere Monitoring Service (CAMS) provides global monitoring of aerosols using the ECMWF forecast model constrained by the assimilation of satellite aerosol optical depth (AOD). This work aims at evaluating the assimilation of the NOAA VIIRS AOD product in the ECMWF model. It shows that the introduction of VIIRS in the CAMS data assimilation system enhances the accuracy of the aerosol analysis, particularly over Europe and desert and maritime sites.
Maria Filioglou, Ari Leskinen, Ville Vakkari, Ewan O'Connor, Minttu Tuononen, Pekko Tuominen, Samuli Laukkanen, Linnea Toiviainen, Annika Saarto, Xiaoxia Shang, Petri Tiitta, and Mika Komppula
Atmos. Chem. Phys., 23, 9009–9021, https://doi.org/10.5194/acp-23-9009-2023, https://doi.org/10.5194/acp-23-9009-2023, 2023
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Pollen impacts climate and public health, and it can be detected in the atmosphere by lidars which measure the linear particle depolarization ratio (PDR), a shape-relevant optical parameter. As aerosols also cause depolarization, surface aerosol and pollen observations were combined with measurements from ground-based lidars operating at different wavelengths to determine the optical properties of birch and pine pollen and quantify their relative contribution to the PDR.
Jesús Abril-Gago, Pablo Ortiz-Amezcua, Diego Bermejo-Pantaleón, Juana Andújar-Maqueda, Juan Antonio Bravo-Aranda, María José Granados-Muñoz, Francisco Navas-Guzmán, Lucas Alados-Arboledas, Inmaculada Foyo-Moreno, and Juan Luis Guerrero-Rascado
Atmos. Chem. Phys., 23, 8453–8471, https://doi.org/10.5194/acp-23-8453-2023, https://doi.org/10.5194/acp-23-8453-2023, 2023
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Validation activities of Aeolus wind products were performed in Granada with different upward-probing instrumentation (Doppler lidar system and radiosondes) and spatiotemporal collocation criteria. Specific advantages and disadvantages of each instrument were identified, and an optimal comparison criterion is proposed. Aeolus was proven to provide reliable wind products, and the upward-probing instruments were proven to be useful for Aeolus wind product validation activities.
Jianyu Zheng, Zhibo Zhang, Hongbin Yu, Anne Garnier, Qianqian Song, Chenxi Wang, Claudia Di Biagio, Jasper F. Kok, Yevgeny Derimian, and Claire Ryder
Atmos. Chem. Phys., 23, 8271–8304, https://doi.org/10.5194/acp-23-8271-2023, https://doi.org/10.5194/acp-23-8271-2023, 2023
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We developed a multi-year satellite-based retrieval of dust optical depth at 10 µm and the coarse-mode dust effective diameter over global oceans. It reveals climatological coarse-mode dust transport patterns and regional differences over the North Atlantic, the Indian Ocean and the North Pacific.
Shikuan Jin, Yingying Ma, Zhongwei Huang, Jianping Huang, Wei Gong, Boming Liu, Weiyan Wang, Ruonan Fan, and Hui Li
Atmos. Chem. Phys., 23, 8187–8210, https://doi.org/10.5194/acp-23-8187-2023, https://doi.org/10.5194/acp-23-8187-2023, 2023
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To better understand the Asian aerosol environment, we studied distributions and trends of aerosol with different sizes and types. Over the past 2 decades, dust, sulfate, and sea salt aerosol decreased by 5.51 %, 3.07 %, and 9.80 %, whereas organic carbon and black carbon aerosol increased by 17.09 % and 6.23 %, respectively. The increase in carbonaceous aerosols was a feature of Asia. An exception is found in East Asia, where the carbonaceous aerosols reduced, owing largely to China's efforts.
Mukunda M. Gogoi, S. Suresh Babu, Ryoichi Imasu, and Makiko Hashimoto
Atmos. Chem. Phys., 23, 8059–8079, https://doi.org/10.5194/acp-23-8059-2023, https://doi.org/10.5194/acp-23-8059-2023, 2023
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Considering the climate warming potential of atmospheric black carbon (BC), satellite-based retrieval is a novel idea. This study highlights the regional distribution of BC based on observations by the Cloud and Aerosol Imager-2 on board the GOSAT-2 satellite and near-surface measurements of BC in ARFINET. The satellite retrieval fairly depicts the regional and seasonal features of BC over the Indian region, which are similar to those recorded by surface observations.
Hao Fan, Xingchuan Yang, Chuanfeng Zhao, Yikun Yang, and Zhenyao Shen
Atmos. Chem. Phys., 23, 7781–7798, https://doi.org/10.5194/acp-23-7781-2023, https://doi.org/10.5194/acp-23-7781-2023, 2023
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Using 20-year multi-source data, this study shows pronounced regional and seasonal variations in fire activities and emissions. Seasonal variability of fires is larger with increasing latitude. The increase in temperature in the Northern Hemisphere's middle- and high-latitude forest regions was primarily responsible for the increase in fires and emissions, while the changes in fire occurrence in tropical regions were more influenced by the decrease in precipitation and relative humidity.
Rosemary Huck, Robert G. Bryant, and James King
Atmos. Chem. Phys., 23, 6299–6318, https://doi.org/10.5194/acp-23-6299-2023, https://doi.org/10.5194/acp-23-6299-2023, 2023
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This study shows that mineral aerosol (dust) emission events in high-latitude areas are under-represented in both ground- and space-based detecting methods. This is done through a suite of ground-based data to prove that dust emissions from the proglacial area, Lhù’ààn Mân, occur almost daily but are not always recorded at different timescales. Dust has multiple effects on atmospheric processes; therefore, accurate quantification is important in the calibration and validation of climate models.
Michail Mytilinaios, Sara Basart, Sergio Ciamprone, Juan Cuesta, Claudio Dema, Enza Di Tomaso, Paola Formenti, Antonis Gkikas, Oriol Jorba, Ralph Kahn, Carlos Pérez García-Pando, Serena Trippetta, and Lucia Mona
Atmos. Chem. Phys., 23, 5487–5516, https://doi.org/10.5194/acp-23-5487-2023, https://doi.org/10.5194/acp-23-5487-2023, 2023
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Multiscale Online Non-hydrostatic AtmospheRe CHemistry model (MONARCH) dust reanalysis provides a high-resolution 3D reconstruction of past dust conditions, allowing better quantification of climate and socioeconomic dust impacts. We assess the performance of the reanalysis needed to reproduce dust optical depth using dust-related products retrieved from satellite and ground-based observations and show that it reproduces the spatial distribution and seasonal variability of atmospheric dust well.
Jacob Z. Tindan, Qinjian Jin, and Bing Pu
Atmos. Chem. Phys., 23, 5435–5466, https://doi.org/10.5194/acp-23-5435-2023, https://doi.org/10.5194/acp-23-5435-2023, 2023
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We use the Infrared Atmospheric Sounder Interferometer (IASI) retrievals of dust variables (dust optical depth and dust layer height) and surface observations to understand the day- and nighttime variations in dust aerosols over the dust belt. Our results show that daytime dust aerosols are significantly different from nighttime, and such day–night variations are influenced by meteorological factors such as wind speed, precipitation, and turbulent motions within the atmospheric boundary layer.
Ross Herbert and Philip Stier
Atmos. Chem. Phys., 23, 4595–4616, https://doi.org/10.5194/acp-23-4595-2023, https://doi.org/10.5194/acp-23-4595-2023, 2023
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We provide robust evidence from multiple sources showing that smoke from fires in the Amazon rainforest significantly modifies the diurnal cycle of convection and cools the climate. Low to moderate amounts of smoke increase deep convective clouds and rain, whilst beyond a threshold amount, the smoke starts to suppress the convection and rain. We are currently at this threshold, suggesting increases in fires from agricultural practices or droughts will reduce cloudiness and rain over the region.
Yue Huang, Jasper F. Kok, Masanori Saito, and Olga Muñoz
Atmos. Chem. Phys., 23, 2557–2577, https://doi.org/10.5194/acp-23-2557-2023, https://doi.org/10.5194/acp-23-2557-2023, 2023
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Global aerosol models and remote sensing retrievals use dust optical models with inconsistent and inaccurate dust shape approximations. Here, we present a new dust optical model constrained by measured dust shape distributions. This new dust optical model is an improvement on the current dust optical models used in models and retrieval algorithms, as quantified by comparisons against laboratory and field observations of dust optics.
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.
María Ángeles López-Cayuela, Carmen Córdoba-Jabonero, Diego Bermejo-Pantaleón, Michaël Sicard, Vanda Salgueiro, Francisco Molero, Clara Violeta Carvajal-Pérez, María José Granados-Muñoz, Adolfo Comerón, Flavio T. Couto, Rubén Barragán, María-Paz Zorzano, Juan Antonio Bravo-Aranda, Constantino Muñoz-Porcar, María João Costa, Begoña Artíñano, Alejandro Rodríguez-Gómez, Daniele Bortoli, Manuel Pujadas, Jesús Abril-Gago, Lucas Alados-Arboledas, and Juan Luis Guerrero-Rascado
Atmos. Chem. Phys., 23, 143–161, https://doi.org/10.5194/acp-23-143-2023, https://doi.org/10.5194/acp-23-143-2023, 2023
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An intense Saharan dust outbreak crossing the Iberian Peninsula in springtime was monitored to determinine the specific contribution of fine and coarse dust particles at five lidar stations, strategically covering its SW–central–NE pathway. Expected dust ageing along the transport started unappreciated. A different fine-dust impact on optical (~30 %) and mass (~10 %) properties was found. Use of polarized lidar measurements (mainly in elastic systems) for fine/coarse dust separation is crucial.
Kyriakoula Papachristopoulou, Ioannis-Panagiotis Raptis, Antonis Gkikas, Ilias Fountoulakis, Akriti Masoom, and Stelios Kazadzis
Atmos. Chem. Phys., 22, 15703–15727, https://doi.org/10.5194/acp-22-15703-2022, https://doi.org/10.5194/acp-22-15703-2022, 2022
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Megacities' air quality is determined by atmospheric aerosols. We focus on changes over the last two decades in the 81 largest cities, using satellite data. European and American cities have lower aerosol compared to African and Asian cities. For European, North American and East Asian cities, aerosols are decreasing over time, especially in China and the US. In the remaining cities, aerosol loads are increasing, particularly in India.
Nilton Évora do Rosário, Elisa Thomé Sena, and Marcia Akemi Yamasoe
Atmos. Chem. Phys., 22, 15021–15033, https://doi.org/10.5194/acp-22-15021-2022, https://doi.org/10.5194/acp-22-15021-2022, 2022
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The 2020 burning season in Brazil was marked by an atypically high number of fire spots across Pantanal, leading to high amounts of smoke within the biome. This study shows that smoke over Pantanal, usually a fraction of that over Amazonia, was higher and resulted mainly from fires in conservation and indigenous areas. It also contributes to highlighting Pantanal's 2020 burning season as the worst combination of a climate extreme scenario and inadequately enforced environmental regulations.
Santiago Gassó and Kirk D. Knobelspiesse
Atmos. Chem. Phys., 22, 13581–13605, https://doi.org/10.5194/acp-22-13581-2022, https://doi.org/10.5194/acp-22-13581-2022, 2022
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Atmospheric particles interact with light resulting in observable optical polarization. Thus, we can learn about their composition from space. New satellite sensor technology measures full polarization of reflected sunlight. This paper considers circular polarization, an overlooked category of polarization with distinctive features that could bring new insights. We review existing literature and make novel computations to consider this previously underappreciated category of polarization.
Qingyang Xiao, Guannan Geng, Shigan Liu, Jiajun Liu, Xia Meng, and Qiang Zhang
Atmos. Chem. Phys., 22, 13229–13242, https://doi.org/10.5194/acp-22-13229-2022, https://doi.org/10.5194/acp-22-13229-2022, 2022
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We provided complete coverage PM2.5 concentrations at a 1-km resolution from 2000 to the present, carefully considering the significant changes in land use characteristics in China. This high-resolution PM2.5 data successfully revealed the local-scale PM2.5 variations. We noticed changes in PM2.5 spatial patterns in association with the clean air policies, with the pollution hotspots having transferred from urban centers to rural regions with limited air quality monitoring.
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Short summary
Dusts have a significant impact on climate and environment. Detecting dust using satellite instruments is generally conducted by measuring at multiple observation angles due to the uncertainty of the surface reflection. This report shows that the degree of polarization of reflected light can be used for retrieving the optical depth of dust at backscatter angles only, regardless of surface conditions. This simple method is suitable for surveying dust aerosols over oceans with low-cost satellites.
Dusts have a significant impact on climate and environment. Detecting dust using satellite...
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