Special issue |
EARLINET aerosol profiling: contributions to atmospheric and climate research
Editor(s): V. Amiridis, L. Mona, A. Ansmann, E. Landulfo, R. Kahn, and M. TescheMore information
The EARLINET ACP Special Issue aims to collect high-quality aerosol studies employing advanced lidar remote sensing techniques as developed within EARLINET, the European Aerosol Research Lidar Network. EARLINET was established in 2000 with the main goal of providing a comprehensive, quantitative, and statistically significant database for aerosol distribution on a continental scale. The 5-year EARLINET-ASOS (Advanced Sustainable Observation System) EC Project (2006–2011) has strongly contributed to optimizing the operation of the network. EARLINET is now a key component of the ACTRIS (Aerosols, Clouds and Trace gases Research InfraStructure Network) research infrastructure project that aims to integrate European ground-based stations equipped with advanced atmospheric probing instrumentation for aerosols, clouds and short-lived gas-phase species. The 15-year EARLINET database of aerosol profiles over Europe will be utilized in this Special Issue to reveal the network’s contribution to atmospheric and climate research.
Measurements of the multi-wavelength Raman polarization lidar PollyXT have been combined with measurements of pollen type and concentration using a traditional pollen sampler at a rural forest site in Kuopio, Finland. The depolarization ratio was enhanced when there were pollen grains in the atmosphere, illustrating the potential of lidar to track pollen grains in the atmosphere. The depolarization ratio of pure pollen particles was assessed for birch and pine pollen using a novel algorithm.
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
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.
Preprint under review for ACP(discussion: final response, 2 comments)
We present retrievals of tropospheric and stratospheric height profiles of particle mass, volume, surface area concentration of wildfire smoke layers and related cloud condensation nucleus (CCN) and ice-nucleating particle (INP) concentrations. The new analysis scheme is applied to stratospheric CALIPSO observations of fresh smoke plumes over northern Canada
in 2017 and New Zealand in January 2020 and to lidar observation of aged Australian wildfire smoke in southern Chile.
Anna Gialitaki, Alexandra Tsekeri, Vassilis Amiridis, Romain Ceolato, Lucas Paulien, Anna Kampouri, Antonis Gkikas, Stavros Solomos, Eleni Marinou, Moritz Haarig, Holger Baars, Albert Ansmann, Tatyana Lapyonok, Anton Lopatin, Oleg Dubovik, Silke Groß, Martin Wirth, Maria Tsichla, Ioanna Tsikoudi, and Dimitris Balis
Stratospheric smoke particles are found to significantly depolarize incident light, while this effect is also accompanied by a strong spectral dependence. We utilize scattering simulations to show that this behaviour can be attributed to the near-spherical shape of the particles. We also examine whether an extension of the current AERONET scattering model to include the near-spherical shapes could be of benefit to the AERONET retrieval for stratospheric smoke associated with enhanced PLDR.
Biomass burning events measured by EARLINET are analysed using intensive parameters. The pollution layers are labelled smoke layers if fires were found along the air-mass back trajectory. The number of contributing fires to the smoke measurements is quantified. It is shown that most of the time we measure mixed smoke. The methodology provides three research directions: fires measured by several stations, long-range transport from N. America, and an analysis function of continental sources.
Revised manuscript accepted for ACP(discussion: closed, 4 comments)
We introduce an automated aerosol type classification method, SCAN. The output of SCAN is compared with two aerosol classification methods: (1) Mahalanobis distance automatic aerosol type classification and Neural Network Aerosol Typing Algorithm. A total of 97 free tropospheric aerosol layers from 4 EARLINET stations in the period 2014–2018 were classified.
Nikolaos Papagiannopoulos, Giuseppe D'Amico, Anna Gialitaki, Nicolae Ajtai, Lucas Alados-Arboledas, Aldo Amodeo, Vassilis Amiridis, Holger Baars, Dimitris Balis, Ioannis Binietoglou, Adolfo Comerón, Davide Dionisi, Alfredo Falconieri, Patrick Fréville, Anna Kampouri, Ina Mattis, Zoran Mijić, Francisco Molero, Alex Papayannis, Gelsomina Pappalardo, Alejandro Rodríguez-Gómez, Stavros Solomos, and Lucia Mona
Volcanic and desert dust particles affect human activities in manifold ways; consequently, mitigation tools are important. Their early detection and the issuance of early warnings are key elements in the initiation of operational response procedures. A methodology for the early warning of these hazards using European Aerosol Research Lidar Network (EARLINET) data is presented. The tailored product is investigated during a volcanic eruption and mineral dust advected in the eastern Mediterranean.
For the first time, a dense data set of particle extinction-to-backscatter ratios (lidar ratios), depolarization ratios, and backscatter- and extinction-related Ångström exponents for a Central Asian site are presented. The observations were performed with a continuously running multiwavelength polarization Raman lidar at Dushanbe, Tajikistan, during an 18-month campaign. The found optical properties reflect the large range of occurring aerosol mixtures.
Mariana Adam, Doina Nicolae, Livio Belegante, Iwona S. Stachlewska, Lucja Janicka, Dominika Szczepanik, Maria Mylonaki, Christiana Anna Papanikolaou, Nikos Siomos, Kalliopi Artemis Voudouri, Luca Alados-Arboledas, Juan Antonio Bravo-Aranda, Arnoud Apituley, Nikolaos Papagiannopoulos, Lucia Mona, Ina Mattis, Anatoli Chaikovsky, Michaël Sicard, Constantino Muñoz-Porcar, Aleksander Pietruczuk, Daniele Bortoli, Holger Baars, Ivan Grigorov, and Zahary Peshev
Revised manuscript under review for ACP(discussion: final response, 4 comments)
Results over 10 years of biomass burning events measured by EARLINET are analysed by means of the intensive parameters based on the methodology described in Part I. Smoke type is characterized for each of the four geographical regions based on continental smoke origin. Relationships between intensive parameters or colour ratios are shown. The smoke is labelled in average as aged smoke. The local smoke has a smaller lidar ratio while the depolarization is smaller for long range transported smoke.
Revised manuscript accepted for ACP(discussion: closed, 4 comments)
The aim of this study is to investigate the potential of GOME-2 instrument on board the MetOpA, MetOpB and MetOpC platforms, to deliver accurate geometrical features of lofted aerosol layers. For this purpose, we use archived ground-based lidar data from lidar stations available from European Aerosol Research Lidar Network (EARLINET) database. We show that for, this well-developed and spatially well-spread aerosol layer, most GOME-2 retrievals fall within 1 km of the exactly temporally collocated.
Revised manuscript accepted for ACP(discussion: closed, 3 comments)
Lidar (light detection and ranging) is a class of remote sensing instruments that are widely used for the monitoring of aerosol properties in the lower levels of the atmosphere, yet their measurements are affected by several sources of uncertainty. Here we present the first comparison of two lidar systems against a fully independent instrument carried by meteorological balloons. We show that both lidars achieve a good agreement with the high precision balloon measurements up to 6 km altitude.
For the first time, continuous, vertically resolved long-term aerosol measurements were conducted with a state-of-the-art multiwavelength lidar over a Central Asian site. Such observations are urgently required in efforts to predict future climate and environmental conditions and to support spaceborne remote sensing (ground truth activities).
Holger Baars, Albert Ansmann, Kevin Ohneiser, Moritz Haarig, Ronny Engelmann, Dietrich Althausen, Ingrid Hanssen, Michael Gausa, Aleksander Pietruczuk, Artur Szkop, Iwona S. Stachlewska, Dongxiang Wang, Jens Reichardt, Annett Skupin, Ina Mattis, Thomas Trickl, Hannes Vogelmann, Francisco Navas-Guzmán, Alexander Haefele, Karen Acheson, Albert A. Ruth, Boyan Tatarov, Detlef Müller, Qiaoyun Hu, Thierry Podvin, Philippe Goloub, Igor Veselovskii, Christophe Pietras, Martial Haeffelin, Patrick Fréville, Michaël Sicard, Adolfo Comerón, Alfonso Javier Fernández García, Francisco Molero Menéndez, Carmen Córdoba-Jabonero, Juan Luis Guerrero-Rascado, Lucas Alados-Arboledas, Daniele Bortoli, Maria João Costa, Davide Dionisi, Gian Luigi Liberti, Xuan Wang, Alessia Sannino, Nikolaos Papagiannopoulos, Antonella Boselli, Lucia Mona, Giuseppe D'Amico, Salvatore Romano, Maria Rita Perrone, Livio Belegante, Doina Nicolae, Ivan Grigorov, Anna Gialitaki, Vassilis Amiridis, Ourania Soupiona, Alexandros Papayannis, Rodanthi-Elisaveth Mamouri, Argyro Nisantzi, Birgit Heese, Julian Hofer, Yoav Y. Schechner, Ulla Wandinger, and Gelsomina Pappalardo
Measurements of the multiwavelength Raman polarization lidar PollyXT have been combined with measurements of pollen type and concentration using a traditional pollen sampler at the rural forest site in Vehmasmäki, Finland. High particle depolarization ratios were observed during an intense pollination event of birch pollen occasionally mixed with spruce pollen. Our observations illustrate the potential of the particle depolarization ratio to track pollen grains in the atmosphere.
Jose Antonio Benavent-Oltra, Roberto Román, Juan Andrés Casquero-Vera, Daniel Pérez-Ramírez, Hassan Lyamani, Pablo Ortiz-Amezcua, Andrés Esteban Bedoya-Velásquez, Gregori de Arruda Moreira, África Barreto, Anton Lopatin, David Fuertes, Milagros Herrera, Benjamin Torres, Oleg Dubovik, Juan Luis Guerrero-Rascado, Philippe Goloub, Francisco Jose Olmo-Reyes, and Lucas Alados-Arboledas
In this paper, we use the GRASP algorithm combining different
remote-sensing measurements to obtain the aerosol vertical and column properties, both during the day and at night-time. The column properties are compared with AERONET products, and the vertical properties retrieved by GRASP are compared with in situ measurements at high-altitude stations. As an originality, we proposed three new schemes to retrieve the night-time aerosol properties.
The use of satellite data is of great interest for the determination of aerosol radiative forcing at regional or even global scales, as previous studies in the literature are predominantly only valid locally. A methodology to retrieve 2-D dust radiative effects with large spatial and temporal coverage based on combined satellite data from CALIPSO, MODIS and CERES is presented and evaluated against well-established methods based on ground-based lidar measurements, obtaining quite good results.
To increase accuracy and validate satellite-based products, comparison with ground-based reference observations is required. To do this, we present evaluation activity of EARLINET for the qualitative and quantitative assessment of NASA's CATS lidar operating aboard the International Space Station (ISS) while identified discrepancies are discussed. Better understanding CATS performance and limitations provides a valuable basis for scientific studies implementing the satellite-based lidar system.
The present study demonstrates the capability of a Raman lidar to monitor aerosol hygroscopic processes. The results showed a higher hygroscopicity and wavelength dependency for smoke particles than for mineral dust. The higher sensitivity of the shortest wavelength to hygroscopic growth found for smoke particles was qualitatively reproduced using Mie simulations. The impact of aerosol hygroscopicity on the Earth's radiative balance has been evaluated using a radiative transfer model.
We assess the feasibility of ground-based and spaceborne lidars to retrieve profiles of cloud-relevant aerosol concentrations and ice-nucleating particles. The retrieved profiles are in good agreement with airborne in situ measurements. Our methodology will be applied to satellite observations in the future so as to provide a global 3D product of cloud-relevant properties.
In this study, a first attempt at comparing and evaluating two classification tools developed within EARLINET that provide near-real-time aerosol typing information for the lidar profiles of Thessaloniki is presented. Our aim is (i) to check the performance of both supervised learning techniques in their low-resolution mode and (ii) to investigate the reasons for typing agreement and disagreement with respect to the uncertainties and the threshold criteria applied.
The episode of elevated sulfate aerosols over eastern Austria during 1–6 April 2014 is analyzed using in situ measurements, EARLINET lidar measurements, CAMS reanalysis data, and backward simulations with the FLEXPART Lagrangian dispersion model. It was found that the lowest layers came from central Europe, while at higher levels, sources in NW Africa and the eastern US contributed. The methodology can be used as a tool to relate in situ and EARLINET measurements.
Gregori de Arruda Moreira, Juan Luis Guerrero-Rascado, Jose A. Benavent-Oltra, Pablo Ortiz-Amezcua, Roberto Román, Andrés E. Bedoya-Velásquez, Juan Antonio Bravo-Aranda, Francisco Jose Olmo Reyes, Eduardo Landulfo, and Lucas Alados-Arboledas
In this study we show the capabilities of combining different remote sensing systems (microwave radiometer – MWR, Doppler lidar – DL – and elastic lidar – EL) for retrieving a detailed picture of the PBL turbulent features. Concerning EL, in addition to analyzing the influence of noise, we explore the use of different wavelengths, which usually includes EL systems operated in extended networks, like EARLINET, LALINET, MPLNET or SKYNET.
Smoke plumes generated in Canadian fire activities were elevated to the lower stratosphere and transported from North America to Europe. The smoke plumes were observed by three lidar systems in northern France. This study provides a comprehensive characterization for aged smoke aerosols at high altitude using lidar observations. It presents that fire activities on the Earth's surface can be an important contributor of stratospheric aerosols and impact the Earth's radiation budget.
A stand-alone automatic method for typing observations of the European Aerosol Research Lidar Network (EARLINET) is presented. The method compares the observations to model distributions that were constructed using EARLINET pre-classified data. The algorithm’s versatility and adaptability makes it suitable for network-wide typing studies.
A new aerosol typing algorithm based on artificial neural networks (ANNs) has been developed. The algorithm is providing the most probable aerosol type based on EARLINET LIDAR profiles. The ANNs used by the algorithm were trained using synthetic data, for which a new aerosol model has been developed. Blind tests on EARLINET data samples showed the capability of the algorithm to retrieve the aerosol type from a large variety of data, with different quality and physical content.
In this study we investigate the climatological behavior of the aerosol optical properties over Thessaloniki during the years 2003–2017. For this purpose, measurements from two individual networks, the European Lidar Aerosol Network (EARLINET) and the Aerosol Robotic Network (AERONET), were deployed. The analysis implies that the EARLINET sampling schedule can be quite effective in producing data that can be applied to
Extremely large light extinction coefficients of 500 Mm-1, about 20 times higher than after the Pinatubo volcanic eruptions in 1991, were observed by EARLINET lidars in the stratosphere over central Europe from 21 to 22 August, 2017. This paper provides an overview based on ground-based (lidar, AERONET) and satellite (MODIS, OMI) remote sensing.
The worldwide only triple-wavelength polarization/Raman lidar was used to measure optical, microphysical, and morphological properties of aged Canadian wildfire smoke occurring in the troposphere and stratosphere over Leipzig, Germany, in August 2017. A strong contrast between the tropospheric and stratospheric smoke properties was found.
Andrés Esteban Bedoya-Velásquez, Francisco Navas-Guzmán, María José Granados-Muñoz, Gloria Titos, Roberto Román, Juan Andrés Casquero-Vera, Pablo Ortiz-Amezcua, Jose Antonio Benavent-Oltra, Gregori de Arruda Moreira, Elena Montilla-Rosero, Carlos David Hoyos, Begoña Artiñano, Esther Coz, Francisco José Olmo-Reyes, Lucas Alados-Arboledas, and Juan Luis Guerrero-Rascado
This study focuses on the analysis of aerosol hygroscopic growth during the SLOPE I campaign combining active and passive remote sensors at ACTRIS Granada station and in situ instrumentation at a mountain station (Sierra Nevada station, SNS). The results showed good agreement on gamma parameters by using remote sensing with respect to those calculated using Mie theory at SNS, with relative differences lower than 9 % at 532 nm and 11 % at 355 nm.
This study presents an evaluation of an air quality model using aerosol measurements from radiometric and lidar data at Thessaloniki, Greece. The aerosol mass concentration profiles of CAMx are compared against the fine and coarse mode aerosol concentration profiles retrieved by the Lidar-Radiometer Inversion Code (LIRIC). The CAMx model and the LIRIC algorithm results were compared in terms of mean mass concentration profiles, center of mass and integrated mass concentration.
Pablo Ortiz-Amezcua, Juan Luis Guerrero-Rascado, María José Granados-Muñoz, José Antonio Benavent-Oltra, Christine Böckmann, Stefanos Samaras, Iwona S. Stachlewska, Łucja Janicka, Holger Baars, Stephanie Bohlmann, and Lucas Alados-Arboledas
Strong events of biomass burning aerosol transported from North American forest fires were detected during July 2013 at three European stations from EARLINET. Satellite observations and models were used to estimate the smoke sources and transport paths. Using lidar techniques and regularization algorithms, the aerosol layers were optically and microphysically characterized, finding some common features among the events, concerning the similar aging processes undergone by the particles.
We provide a 3D multiyear analysis on the evolution of Saharan dust over Europe, using a dust product retrieved from the CALIPSO satellite and using EARLINET methods. The results reveal for the first time the 9-year 3D seasonal patterns of dust over its transport paths from the Sahara towards the Mediterranean. The dataset is unique with respect to its potential applications, including the evaluation of dust models and the estimation of ice nuclei concentration profiles from space.
An extreme dust storm affected Middle East and the Eastern Mediterranean in September 2015. This event was produced by a combination of meteorological and land-use properties. Analysis with remote sensing observations and modeling simulations reveals (i) transport of warm moist air from the Red and Arabian seas, (ii) formation of a thermal low over Syria, (iii) convective outflows and haboob formation (i.e. propagating dust walls), and (iv) changes in land-use and dust erodibility due to war.
Dimitris Balis, Maria-Elissavet Koukouli, Nikolaos Siomos, Spyridon Dimopoulos, Lucia Mona, Gelsomina Pappalardo, Franco Marenco, Lieven Clarisse, Lucy J. Ventress, Elisa Carboni, Roy G. Grainger, Ping Wang, Gijsbert Tilstra, Ronald van der A, Nicolas Theys, and Claus Zehner
The ESA-funded SACS-2 and SMASH projects developed and improved dedicated satellite-derived ash plume and sulfur dioxide level assessments. These estimates were validated using ground-based and aircraft lidar measurements. The validation results are promising for most satellite products and are within the estimated uncertainties of each of the comparative data sets. The IASI data show a better consistency concerning the ash optical depth and ash layer height.
Nikolaos Papagiannopoulos, Lucia Mona, Lucas Alados-Arboledas, Vassilis Amiridis, Holger Baars, Ioannis Binietoglou, Daniele Bortoli, Giuseppe D'Amico, Aldo Giunta, Juan Luis Guerrero-Rascado, Anja Schwarz, Sergio Pereira, Nicola Spinelli, Ulla Wandinger, Xuan Wang, and Gelsomina Pappalardo
Satellite-derived products must undergo data evaluation with reference data sets in order to identify any possible reasons of discrepancy or to assess their representativity. In that direction, data coming from CALIPSO satellite were compared with observations from the ground. We identified a CALIPSO underestimation that could be linked to an assumption in the satellites' algorithms. The proposed correction improves the performance and could enhance aerosol modeling.