Articles | Volume 7, issue 6
https://doi.org/10.5194/amt-7-1711-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/amt-7-1711-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
17 Jun 2014
Research article |
| 17 Jun 2014
A high-resolution oxygen A-band spectrometer (HABS) and its radiation closure
Q. Min
Atmospheric Science Research Center, State University of New York, Albany NY 12203, USA
Atmospheric Science Research Center, State University of New York, Albany NY 12203, USA
S. Li
Atmospheric Science Research Center, State University of New York, Albany NY 12203, USA
J. Berndt
Atmospheric Science Research Center, State University of New York, Albany NY 12203, USA
L. Harrison
Atmospheric Science Research Center, State University of New York, Albany NY 12203, USA
E. Joseph
Atmospheric Science Research Center, State University of New York, Albany NY 12203, USA
M. Duan
LAGEO, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
P. Kiedron
Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA
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Nofel Lagrosas, Kosuke Okubo, Hitoshi Irie, Yutaka Matsumi, Tomoki Nakayama, Yutaka Sugita, Takashi Okada, and Tatsuo Shiina
Atmos. Meas. Tech., 16, 5937–5951, https://doi.org/10.5194/amt-16-5937-2023, https://doi.org/10.5194/amt-16-5937-2023, 2023
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This work examines the near-ground aerosol–weather relationship from 7-month continuous lidar and weather observations in Chiba, Japan. Optical parameters from lidar data are compared with weather parameters to understand and quantify the aerosol–weather relationship and how these optical parameters are affected by the weather and season. The results provide insights into analyzing optical properties of radioactive aerosols when the lidar system is continuously operated in a radioactive area.
Igor Veselovskii, Nikita Kasianik, Mikhail Korenskii, Qiaoyun Hu, Philippe Goloub, Thierry Podvin, and Dong Liu
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A five-channel fluorescence lidar was developed for the study of atmospheric aerosol. The fluorescence spectrum induced by 355 nm laser emission is analyzed in five spectral intervals, namely 438 and 29, 472 and 32, 513 and 29, 560 and 40, and 614 and 54 nm. This lidar system was operated during strong forest fires. Our results demonstrate that, for urban aerosol, the maximal fluorescence backscattering is observed at 472 nm, while for smoke, the spectrum is shifted toward longer wavelengths.
Emily D. Lenhardt, Lan Gao, Jens Redemann, Feng Xu, Sharon P. Burton, Brian Cairns, Ian Chang, Richard A. Ferrare, Chris A. Hostetler, Pablo E. Saide, Calvin Howes, Yohei Shinozuka, Snorre Stamnes, Mary Kacarab, Amie Dobracki, Jenny Wong, Steffen Freitag, and Athanasios Nenes
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Nick Gorkavyi, Nickolay Krotkov, and Alexander Marshak
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The article discusses topical issues of the visible (libration) motion of the Earth in the sky of the Moon in a rectangle measuring 13.4° × 15.8°. On the one hand, the librations of the Moon make these observations difficult. On the other hand, they can be used as a natural scanning mechanism for cameras and spectroscopes mounted on a fixed platform on the surface of the Moon.
Norman T. O'Neill, Keyvan Ranjbar, Liviu Ivănescu, Thomas F. Eck, Jeffrey S. Reid, David M. Giles, Daniel Pérez-Ramírez, and Jai Prakash Chaubey
Atmos. Meas. Tech., 16, 1103–1120, https://doi.org/10.5194/amt-16-1103-2023, https://doi.org/10.5194/amt-16-1103-2023, 2023
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Aerosols are atmospheric particles that vary in size (radius) from a fraction of a micrometer (µm) to around 20 µm. They tend to be either smaller than 1 µm (like smoke or pollution) or larger than 1 µm (like dust or sea salt). Their optical effect (scattering and absorbing sunlight) can be divided into FM (fine-mode) and CM (coarse-mode) parts using a cutoff radius around 1 µm or a spectral (color) technique. We present and validate a theoretical link between the types of FM and CM divisions.
Nakul N. Karle, Ricardo K. Sakai, Rosa M. Fitzgerald, Charles Ichoku, Fernando Mercado, and William R. Stockwell
Atmos. Meas. Tech., 16, 1073–1085, https://doi.org/10.5194/amt-16-1073-2023, https://doi.org/10.5194/amt-16-1073-2023, 2023
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Extensive virga research is uncommon, even though it is a common phenomenon. A systematic method was developed to characterize virga using available datasets. In total, 50 virga events were observed, appearing only during a specific time of the year, revealing a seasonal pattern. These virga events were identified and classified, and their impact on surface PM measurements was investigated. A more detailed examination of the selected events reveals that virga impacts regional air quality.
Jens Reichardt, Oliver Behrendt, and Felix Lauermann
Atmos. Meas. Tech., 16, 1–13, https://doi.org/10.5194/amt-16-1-2023, https://doi.org/10.5194/amt-16-1-2023, 2023
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The UVA spectrometer is the latest instrumental addition to the spectrometric fluorescence and Raman lidar RAMSES. The redesigned receiver and the data analysis of the fluorescence measurement are described. Furthermore, the effect of aerosol fluorescence on humidity measurements is studied. It turns out that Raman lidars equipped with a spectrometer show superior performance over those with one discrete fluorescence detection channel only. The cause is variability in the fluorescence spectrum.
Jie Luo, Zhengqiang Li, Cheng Fan, Hua Xu, Ying Zhang, Weizhen Hou, Lili Qie, Haoran Gu, Mengyao Zhu, Yinna Li, and Kaitao Li
Atmos. Meas. Tech., 15, 2767–2789, https://doi.org/10.5194/amt-15-2767-2022, https://doi.org/10.5194/amt-15-2767-2022, 2022
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A single model is difficult to represent various shapes of dust. We proposed a tunable model to represent dust with various shapes. Two tunable parameters were used to represent the effects of the erosion degree and binding forces from the mass center. Thus, the model can represent various dust shapes by adjusting the tunable parameters. Besides, the applicability of the spheroid model in calculating the optical properties and polarimetric characteristics is evaluated.
Peristera Paschou, Nikolaos Siomos, Alexandra Tsekeri, Alexandros Louridas, George Georgoussis, Volker Freudenthaler, Ioannis Binietoglou, George Tsaknakis, Alexandros Tavernarakis, Christos Evangelatos, Jonas von Bismarck, Thomas Kanitz, Charikleia Meleti, Eleni Marinou, and Vassilis Amiridis
Atmos. Meas. Tech., 15, 2299–2323, https://doi.org/10.5194/amt-15-2299-2022, https://doi.org/10.5194/amt-15-2299-2022, 2022
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The eVe lidar delivers quality-assured aerosol and cloud optical properties according to the standards of ACTRIS. It is a mobile reference system for the validation of the ESA's Aeolus satellite mission (L2 aerosol and cloud products). eVe provides linear and circular polarisation measurements with Raman capabilities. Here, we describe the system design, the polarisation calibration techniques, and the software for the retrieval of the optical products.
Yu Zheng, Huizheng Che, Yupeng Wang, Xiangao Xia, Xiuqing Hu, Xiaochun Zhang, Jun Zhu, Jibiao Zhu, Hujia Zhao, Lei Li, Ke Gui, and Xiaoye Zhang
Atmos. Meas. Tech., 15, 2139–2158, https://doi.org/10.5194/amt-15-2139-2022, https://doi.org/10.5194/amt-15-2139-2022, 2022
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Ground-based observations of aerosols and aerosol data verification is important for satellite and climate model modification. Here we present an evaluation of aerosol microphysical, optical and radiative properties measured using a multiwavelength photometer with a highly integrated design and smart control performance. The validation of this product is discussed in detail using AERONET as a reference. This work contributes to reducing AOD uncertainties in China and combating climate change.
Alexandra Tsekeri, Vassilis Amiridis, Alexandros Louridas, George Georgoussis, Volker Freudenthaler, Spiros Metallinos, George Doxastakis, Josef Gasteiger, Nikolaos Siomos, Peristera Paschou, Thanasis Georgiou, George Tsaknakis, Christos Evangelatos, and Ioannis Binietoglou
Atmos. Meas. Tech., 14, 7453–7474, https://doi.org/10.5194/amt-14-7453-2021, https://doi.org/10.5194/amt-14-7453-2021, 2021
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Dust orientation in the Earth's atmosphere has been an ongoing investigation in recent years, and its potential proof will be a paradigm shift for dust remote sensing. We have designed and developed a polarization lidar that provides direct measurements of dust orientation, as well as more detailed information of the particle microphysics. We provide a description of its design as well as its first measurements.
Liviu Ivănescu, Konstantin Baibakov, Norman T. O'Neill, Jean-Pierre Blanchet, and Karl-Heinz Schulz
Atmos. Meas. Tech., 14, 6561–6599, https://doi.org/10.5194/amt-14-6561-2021, https://doi.org/10.5194/amt-14-6561-2021, 2021
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Starphotometry seeks to provide accurate measures of nocturnal optical depth (OD). It is driven by a need to characterize aerosols and their radiative forcing effects during a very data-sparse period. A sub-0.01 OD error is required to adequately characterize key aerosol parameters. We found approaches for sufficiently mitigating errors to achieve the 0.01 standard. This renders starphotometry the equal of daytime techniques and opens the door to exploiting its distinct star-pointing advantages.
Antti Arola, William Wandji Nyamsi, Antti Lipponen, Stelios Kazadzis, Nickolay A. Krotkov, and Johanna Tamminen
Atmos. Meas. Tech., 14, 4947–4957, https://doi.org/10.5194/amt-14-4947-2021, https://doi.org/10.5194/amt-14-4947-2021, 2021
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Methods to estimate surface UV radiation from satellite measurements offer the only means to obtain global coverage, and the development of satellite-based UV algorithms has been ongoing since the early 1990s. One of the main challenges in this development has been how to account for the overall effect of absorption by atmospheric aerosols. One such method was suggested roughly a decade ago, and in this study we propose further improvements for this kind of approach.
Igor Veselovskii, Qiaoyun Hu, Philippe Goloub, Thierry Podvin, Marie Choël, Nicolas Visez, and Mikhail Korenskiy
Atmos. Meas. Tech., 14, 4773–4786, https://doi.org/10.5194/amt-14-4773-2021, https://doi.org/10.5194/amt-14-4773-2021, 2021
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The multiwavelength Mie–Raman–fluorescence lidar of the University of Lille was used to characterize aerosols during the pollen season in the north of France for the period March–June 2020. The results of observations demonstrate that the presence of pollen grains in aerosol mixtures leads to an increase in the depolarization ratio and to the enhancement of the fluorescence backscattering.
Lewis Grasso, Daniel Bikos, Jorel Torres, John F. Dostalek, Ting-Chi Wu, John Forsythe, Heather Q. Cronk, Curtis J. Seaman, Steven D. Miller, Emily Berndt, Harry G. Weinman, and Kennard B. Kasper
Atmos. Meas. Tech., 14, 1615–1634, https://doi.org/10.5194/amt-14-1615-2021, https://doi.org/10.5194/amt-14-1615-2021, 2021
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This study uses geostationary imagery to detect dust. This research was done to demonstrate the ability of dust detection over ocean surfaces in a dry atmosphere.
Igor Veselovskii, Qiaoyun Hu, Philippe Goloub, Thierry Podvin, Mikhail Korenskiy, Olivier Pujol, Oleg Dubovik, and Anton Lopatin
Atmos. Meas. Tech., 13, 6691–6701, https://doi.org/10.5194/amt-13-6691-2020, https://doi.org/10.5194/amt-13-6691-2020, 2020
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To study the feasibility of a fluorescence lidar for aerosol characterization, the fluorescence channel is added to the multiwavelength Mie-Raman lidar of Lille University. A part of the fluorescence spectrum is selected by the interference filter of 44 nm bandwidth centered at 466 nm. Such an approach has demonstrated high sensitivity, allowing fluorescence signals from weak aerosol layers to be detected. The technique can also be used for monitoring the aerosol inside the cloud layers.
Katta Vijayakumar, Panuganti C. S. Devara, Sunil M. Sonbawne, David M. Giles, Brent N. Holben, Sarangam Vijaya Bhaskara Rao, and Chalicheemalapalli K. Jayasankar
Atmos. Meas. Tech., 13, 5569–5593, https://doi.org/10.5194/amt-13-5569-2020, https://doi.org/10.5194/amt-13-5569-2020, 2020
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The direct-Sun and inversion products of urban atmospheric aerosols, obtained from a Cimel Sun–sky radiometer in Pune, India, under the AERONET program since October 2004, have been reported in this paper. The mean seasonal variations in AOD from cloud-free days indicated greater values during the monsoon season, revealing dominance of hygroscopic aerosols over the station. Such results are sparse in India and are important for estimating aerosol radiative forcing and validating climate models.
Teruyuki Nakajima, Monica Campanelli, Huizheng Che, Victor Estellés, Hitoshi Irie, Sang-Woo Kim, Jhoon Kim, Dong Liu, Tomoaki Nishizawa, Govindan Pandithurai, Vijay Kumar Soni, Boossarasiri Thana, Nas-Urt Tugjsurn, Kazuma Aoki, Sujung Go, Makiko Hashimoto, Akiko Higurashi, Stelios Kazadzis, Pradeep Khatri, Natalia Kouremeti, Rei Kudo, Franco Marenco, Masahiro Momoi, Shantikumar S. Ningombam, Claire L. Ryder, Akihiro Uchiyama, and Akihiro Yamazaki
Atmos. Meas. Tech., 13, 4195–4218, https://doi.org/10.5194/amt-13-4195-2020, https://doi.org/10.5194/amt-13-4195-2020, 2020
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This paper overviews the progress in sky radiometer technology and the development of the network called SKYNET. It is found that the technology has produced useful on-site calibration methods, retrieval algorithms, and data analyses from sky radiometer observations of aerosol, cloud, water vapor, and ozone. The paper also discusses current issues of SKYNET to provide better information for the community.
Grigorii P. Kokhanenko, Yurii S. Balin, Marina G. Klemasheva, Sergei V. Nasonov, Mikhail M. Novoselov, Iogannes E. Penner, and Svetlana V. Samoilova
Atmos. Meas. Tech., 13, 1113–1127, https://doi.org/10.5194/amt-13-1113-2020, https://doi.org/10.5194/amt-13-1113-2020, 2020
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Cirrus clouds consist of crystals (plates, needles) that can orient themselves in space as a result of free fall. This leads to the appearance of various types of optical halo and to specular reflection of solar radiation. The presence of such particles significantly affects the passage of thermal radiation through the mid- and high-level ice clouds. Using the properties of polarization, a scanning lidar makes it possible to identify cloud areas with oriented crystals.
Hans Grob, Claudia Emde, Matthias Wiegner, Meinhard Seefeldner, Linda Forster, and Bernhard Mayer
Atmos. Meas. Tech., 13, 239–258, https://doi.org/10.5194/amt-13-239-2020, https://doi.org/10.5194/amt-13-239-2020, 2020
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Polarimetry has been established as an enhancement to classical photometry in aerosol remote sensing over the past years. We propose a fast and exact radiometric and polarimetric calibration method for polarized photometers. Additionally, a technique for correcting an alt-azimuthal mount is introduced.
These methods are applied to measurements obtained with our SSARA instrument during the A-LIFE field campaign. For 2 d, the data are subjected to an inversion of aerosol optical properties.
Akihiro Uchiyama, Masataka Shiobara, Hiroshi Kobayashi, Tsuneo Matsunaga, Akihiro Yamazaki, Kazunori Inei, Kazuhiro Kawai, and Yoshiaki Watanabe
Atmos. Meas. Tech., 12, 6465–6488, https://doi.org/10.5194/amt-12-6465-2019, https://doi.org/10.5194/amt-12-6465-2019, 2019
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The majority of aerosol data are obtained from daytime measurements using the Sun as a light source, and there are few datasets available for studying nighttime aerosol characteristics. To estimate the aerosol optical depth (AOD) during the nighttime using the moon as a light source, a radiometer for the daytime was modified, and a new calibration method was developed. As a result, the estimations of the nighttime AOD were made with the same degree of precision and accuracy during the daytime.
Chong Wang, Mingjiao Jia, Haiyun Xia, Yunbin Wu, Tianwen Wei, Xiang Shang, Chengyun Yang, Xianghui Xue, and Xiankang Dou
Atmos. Meas. Tech., 12, 3303–3315, https://doi.org/10.5194/amt-12-3303-2019, https://doi.org/10.5194/amt-12-3303-2019, 2019
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To investigate the relationship between BLH and air pollution under different conditions, a compact micro-pulse lidar integrating both direct-detection lidar and coherent Doppler wind lidar is built. Evolution of atmospheric boundary layer height (BLH), aerosol layer and fine structure in cloud base are well retrieved. Negative correlation exists between BLH and PM2.5. Different trends show that the relationship between PM2.5 and BLH should be considered in different boundary layer categories.
Maxence Descheemaecker, Matthieu Plu, Virginie Marécal, Marine Claeyman, Francis Olivier, Youva Aoun, Philippe Blanc, Lucien Wald, Jonathan Guth, Bojan Sič, Jérôme Vidot, Andrea Piacentini, and Béatrice Josse
Atmos. Meas. Tech., 12, 1251–1275, https://doi.org/10.5194/amt-12-1251-2019, https://doi.org/10.5194/amt-12-1251-2019, 2019
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The future Flexible Combined Imager (FCI) on board MeteoSat Third Generation is expected to improve the detection and the quantification of aerosols. The study assesses the potential of FCI/VIS04 channel for monitoring air pollution in Europe. An observing system simulation experiment in MOCAGE is developed, and they show a large positive impact of the assimilation over a 4-month period and particularly during a severe pollution episode. The added value of geostationary data is also assessed.
Charles J. Vernon, Ryan Bolt, Timothy Canty, and Ralph A. Kahn
Atmos. Meas. Tech., 11, 6289–6307, https://doi.org/10.5194/amt-11-6289-2018, https://doi.org/10.5194/amt-11-6289-2018, 2018
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The height that aerosols are injected into the atmosphere can significantly impact the dispersion of aerosol plumes. We use direct observations from the MISR instrument to determine aerosol injection height and constrain the HYSPLIT Dispersion model with these data. We have shown that the nominal plume-rise calculation within HYSPLIT tends to underestimate injection heights of wildfires and that simulations constrained with MISR injection height can show better agreement with MODIS observations.
Akihiro Uchiyama, Tsuneo Matsunaga, and Akihiro Yamazaki
Atmos. Meas. Tech., 11, 5363–5388, https://doi.org/10.5194/amt-11-5363-2018, https://doi.org/10.5194/amt-11-5363-2018, 2018
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Atmospheric aerosols are an important constituent of the atmosphere. Measurement networks using radiometers such as SKYNET have been developed. There are two constants that we must determine to make accurate measurements. One of them is the calibration constant. The accuracy of the current method to determine this was investigated and the new method for water vapor and near-infrared channels was developed. Utilizing the results of this paper, SKYNET measurement data will become more reliable.
Akihiro Uchiyama, Tsuneo Matsunaga, and Akihiro Yamazaki
Atmos. Meas. Tech., 11, 5389–5402, https://doi.org/10.5194/amt-11-5389-2018, https://doi.org/10.5194/amt-11-5389-2018, 2018
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Atmospheric aerosols are an important constituent of the atmosphere. Measurement networks using radiometers such as SKYNET have been developed. There are two constants that we must determine. One of them is the solid view angle (SVA) of the radiometer. The problems related to SVA were investigated. It was shown that the conventional method can cause a systematic underestimation, and an improved method was proposed. Utilizing the results of this paper, SKYNET data will become more reliable.
Ioana Elisabeta Popovici, Philippe Goloub, Thierry Podvin, Luc Blarel, Rodrigue Loisil, Florin Unga, Augustin Mortier, Christine Deroo, Stéphane Victori, Fabrice Ducos, Benjamin Torres, Cyril Delegove, Marie Choël, Nathalie Pujol-Söhne, and Christophe Pietras
Atmos. Meas. Tech., 11, 4671–4691, https://doi.org/10.5194/amt-11-4671-2018, https://doi.org/10.5194/amt-11-4671-2018, 2018
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This paper aims to show the potential of an instrumented mobile platform, performing on-road remote sensing and in situ measurements, to derive aerosol properties. It is distinguished from other transportable platforms through its ability to perform measurements during movement. Its reduced size, versatility and great flexibility makes it suitable for following sudden aerosol events and for validating satellite measurements and model simulations.
Kirk Knobelspiesse and Sreeja Nag
Atmos. Meas. Tech., 11, 3935–3954, https://doi.org/10.5194/amt-11-3935-2018, https://doi.org/10.5194/amt-11-3935-2018, 2018
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We test if small satellites flying in formation can be used for multi-angle aerosol remote sensing. So far, this has only been done with multiple views on one satellite. Single-view angle satellites flying in formation are a technically feasible alternative, although with different geometries. Using Bayesian information content analysis, we find such satellites equally capable. For aerosol remote sensing, the number of viewing angles is the most important.
Landon A. Rieger, Elizaveta P. Malinina, Alexei V. Rozanov, John P. Burrows, Adam E. Bourassa, and Doug A. Degenstein
Atmos. Meas. Tech., 11, 3433–3445, https://doi.org/10.5194/amt-11-3433-2018, https://doi.org/10.5194/amt-11-3433-2018, 2018
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This paper compares aerosol extinction records from two limb scattering instruments, OSIRIS and SCIAMACHY, to that from the occultation instrument SAGE II. Differences are investigated through modelling and retrieval studies and important sources of systematic errors are quantified. It is found that the largest biases come from uncertainties in the aerosol size distribution and the aerosol particle concentration at altitudes above 30 km.
Evgenia Galytska, Vassyl Danylevsky, René Hommel, and John P. Burrows
Atmos. Meas. Tech., 11, 2101–2118, https://doi.org/10.5194/amt-11-2101-2018, https://doi.org/10.5194/amt-11-2101-2018, 2018
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This research assesses the influence of biomass burning during forest fires throughout summer 2010 on aerosol load over Ukraine, the European territory of Russia (ETR) and Eastern Europe. We apply and compare ground-based and satellite measurements to determine aerosol content, dynamics, and properties. With the application of modeling techniques (HYSPLIT), we show that the maximum AOD in August 2010 over Ukraine was caused by particle transport from the forest fires in the ETR.
Livio Belegante, Juan Antonio Bravo-Aranda, Volker Freudenthaler, Doina Nicolae, Anca Nemuc, Dragos Ene, Lucas Alados-Arboledas, Aldo Amodeo, Gelsomina Pappalardo, Giuseppe D'Amico, Francesco Amato, Ronny Engelmann, Holger Baars, Ulla Wandinger, Alexandros Papayannis, Panos Kokkalis, and Sérgio N. Pereira
Atmos. Meas. Tech., 11, 1119–1141, https://doi.org/10.5194/amt-11-1119-2018, https://doi.org/10.5194/amt-11-1119-2018, 2018
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This paper presents different depolarization calibration procedures used to improve the quality of the depolarization data. The results illustrate a significant improvement of the depolarization lidar products for all the selected EARLINET lidar instruments. The calibrated volume and particle depolarization profiles at 532 nm show values that fall within a range that is accepted in the literature. The depolarization accuracy estimate at 532 nm is better than ±0.03 for all cases.
Igor V. Geogdzhayev and Alexander Marshak
Atmos. Meas. Tech., 11, 359–368, https://doi.org/10.5194/amt-11-359-2018, https://doi.org/10.5194/amt-11-359-2018, 2018
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The unique Earth view of the Deep Space Climate Observatory (DSCOVR) Earth Polychromatic Imaging Camera (EPIC) orbiting at the point of equal attraction from the Earth and the Sun can significantly augment the low-orbit remote sensing of aerosols, clouds and gases. We derive the relationship between the digital counts and the reflected sunlight intensity for some EPIC channels using collocated Earth views from EPIC and Moderate Resolution Imaging Spectroradiometer (MODIS) and EPIC moon views.
Panagiotis Kokkalis
Atmos. Meas. Tech., 10, 3103–3115, https://doi.org/10.5194/amt-10-3103-2017, https://doi.org/10.5194/amt-10-3103-2017, 2017
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The mathematical formulation for the optical setup of a typical EARLINET lidar system is given here. The equations describing a lidar system from the emitted laser beam to the projection of the telescope aperture on the final receiving unit (i.e., photomultiplier or photodiode) are presented, based on paraxial approximation and a geometric optics approach. The evaluation of the formulation is performed with ray-tracing simulations on a real system.
Andrew M. Sayer, N. Christina Hsu, Corey Bettenhausen, Robert E. Holz, Jaehwa Lee, Greg Quinn, and Paolo Veglio
Atmos. Meas. Tech., 10, 1425–1444, https://doi.org/10.5194/amt-10-1425-2017, https://doi.org/10.5194/amt-10-1425-2017, 2017
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The satellite instrument VIIRS is being used to carry on observations of the Earth made by older satellites like MODIS. Data sets created from these satellite observations depend on the quality of the satellite instruments' calibration. This paper describes a comparison between the calibration of these two sensors. MODIS is believed to be more reliable and so VIIRS is corrected to bring it in line with MODIS. These corrections are shown to improve the quality of VIIRS aerosol data.
Thomas Carlund, Natalia Kouremeti, Stelios Kazadzis, and Julian Gröbner
Atmos. Meas. Tech., 10, 905–923, https://doi.org/10.5194/amt-10-905-2017, https://doi.org/10.5194/amt-10-905-2017, 2017
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Aerosols play an important role in atmospheric processes. Aerosol optical depth is the most common measure of columnar aerosol load. We present a sunphotometer called UVPFR that is able to measure aerosol optical depth in the ultraviolet range, including the calibration, characterization and validation of the instrument/measurements. The instrument will serve as a reference on the intercalibration of Brewer spectrophotometers that are also able to measure aerosol optical depth in the UV region.
A. Fernando Almansa, Emilio Cuevas, Benjamín Torres, África Barreto, Rosa D. García, Victoria E. Cachorro, Ángel M. de Frutos, César López, and Ramón Ramos
Atmos. Meas. Tech., 10, 565–579, https://doi.org/10.5194/amt-10-565-2017, https://doi.org/10.5194/amt-10-565-2017, 2017
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This study presents a new zenith-looking narrow-band radiometer-based system (ZEN), conceived for dust aerosol optical depth (AOD) monitoring. The ZEN system comprises a robust and automated radiometer (ZEN-R41), and a lookup table methodology for AOD retrieval (ZEN-LUT). Our results suggest that ZEN is a suitable system to fill the current observational gaps and to complement observations performed by sun-photometer networks in order to improve mineral dust monitoring in remote locations.
Stelios Kazadzis, Panagiotis Raptis, Natalia Kouremeti, Vassilis Amiridis, Antti Arola, Evangelos Gerasopoulos, and Gregory L. Schuster
Atmos. Meas. Tech., 9, 5997–6011, https://doi.org/10.5194/amt-9-5997-2016, https://doi.org/10.5194/amt-9-5997-2016, 2016
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Aerosols play an important role in the Earth's climate. One of the main aerosol properties is the single scattering albedo which is a measure of the aerosol absorption. In this work we have presented a method to retrieve this aerosol property in the ultraviolet and we presented the results for measurements at the urban environment of Athens, Greece. We show that the spectral dependence of the aerosol absorption in the VIS–IR and the UV range depends on the aerosol composition and type.
Moritz Haarig, Ronny Engelmann, Albert Ansmann, Igor Veselovskii, David N. Whiteman, and Dietrich Althausen
Atmos. Meas. Tech., 9, 4269–4278, https://doi.org/10.5194/amt-9-4269-2016, https://doi.org/10.5194/amt-9-4269-2016, 2016
Volker Freudenthaler
Atmos. Meas. Tech., 9, 4181–4255, https://doi.org/10.5194/amt-9-4181-2016, https://doi.org/10.5194/amt-9-4181-2016, 2016
Simone Kotthaus, Ewan O'Connor, Christoph Münkel, Cristina Charlton-Perez, Martial Haeffelin, Andrew M. Gabey, and C. Sue B. Grimmond
Atmos. Meas. Tech., 9, 3769–3791, https://doi.org/10.5194/amt-9-3769-2016, https://doi.org/10.5194/amt-9-3769-2016, 2016
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Ceilometers lidars are useful to study clouds, aerosol layers and atmospheric boundary layer structures. As sensor optics and acquisition algorithms can strongly influence the observations, sensor specifics need to be incorporated into the physical interpretation. Here, recommendations are made for the operation and processing of profile observations from the widely deployed Vaisala CL31 ceilometer. Proposed corrections are shown to increase data quality and even data availability at times.
Maxime Hervo, Yann Poltera, and Alexander Haefele
Atmos. Meas. Tech., 9, 2947–2959, https://doi.org/10.5194/amt-9-2947-2016, https://doi.org/10.5194/amt-9-2947-2016, 2016
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Imperfections in a lidar's overlap function lead to artefacts in the lidar (Light Detection and Ranging) signals. These artefacts can erroneously be interpreted as an aerosol gradient or, in extreme cases, as a cloud base leading to false cloud detection. In this study an algorithm is presented to correct such artefacts.
The algorithm is completely automatic and does not require any intervention on site. It is therefore suited for use in large automatic lidar networks.
Aaron R. Naeger, Pawan Gupta, Bradley T. Zavodsky, and Kevin M. McGrath
Atmos. Meas. Tech., 9, 2463–2482, https://doi.org/10.5194/amt-9-2463-2016, https://doi.org/10.5194/amt-9-2463-2016, 2016
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In this study, we merge aerosol information from multiple satellite sensors on board low-earth orbiting (LEO) and geostationary (GEO) platforms in order to provide a more comprehensive understanding of the spatial distribution of aerosols compared to when only using single sensors as is commonly done. Our results show that merging aerosol information from LEO and GEO platforms can be very useful, which paves the way for applications to the more advanced next-generation of satellites.
Ronny Engelmann, Thomas Kanitz, Holger Baars, Birgit Heese, Dietrich Althausen, Annett Skupin, Ulla Wandinger, Mika Komppula, Iwona S. Stachlewska, Vassilis Amiridis, Eleni Marinou, Ina Mattis, Holger Linné, and Albert Ansmann
Atmos. Meas. Tech., 9, 1767–1784, https://doi.org/10.5194/amt-9-1767-2016, https://doi.org/10.5194/amt-9-1767-2016, 2016
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The atmospheric science community demands for autonomous and quality-assured vertically resolved measurements of aerosol and cloud properties. For this purpose, a portable lidar called Polly
was developed at TROPOS in 2003. This lidar type was continuously improved with gained experience from EARLINET, worldwide field campaigns, and institute collaborations within the last 10 years. We present recent changes to the setup of our portable multiwavelength Raman and polarization lidar PollyXT.
Zongming Tao, Zhenzhu Wang, Shijun Yang, Huihui Shan, Xiaomin Ma, Hui Zhang, Sugui Zhao, Dong Liu, Chenbo Xie, and Yingjian Wang
Atmos. Meas. Tech., 9, 1369–1376, https://doi.org/10.5194/amt-9-1369-2016, https://doi.org/10.5194/amt-9-1369-2016, 2016
Short summary
Short summary
A new measurement technology of PM2.5 mass concentration profile near ground is addressed using a CCD side-scatter lidar and a PM2.5 detector.
The PM2.5 mass concentration profile can be built upon the vertical distribution of the extinction coefficient for aerosol. The PM2.5 is always loading in the planet boundary layer with a complex muti-layer structure. The new method for PM2.5 mass concentration profile is useful for improving our understanding of air quality and atmospheric environment.
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