Multi-wavelength Raman lidar, sunphotometric and aircraft measurements in combination with inversion models for the estimation of the aerosol optical and physico-chemical properties over Athens, Greece

Abstract. A novel procedure has been developed to retrieve, simultaneously, the optical, microphysical and chemical properties of tropospheric aerosols with a multi-wavelength Raman lidar system in the troposphere over an urban site (Athens, Greece: 37.9° N, 23.6° E, 200 m a.s.l.) using data obtained during the European Space Agency (ESA) THERMOPOLIS project which took place between 15–31 July 2009 over the Greater Athens Area (GAA). We selected to apply our procedure for a case study of intense aerosol layers occurred on 20–21 July 2009. The National Technical University of Athens (NTUA) EOLE 6-wavelength Raman lidar system has been used to provide the vertical profiles of the optical properties of aerosols (extinction and backscatter coefficients, lidar ratio) and the water vapor mixing ratio. An inversion algorithm was used to derive the mean aerosol microphysical properties (mean effective radius – reff), single-scattering albedo (ω) and mean complex refractive index (m) at selected heights in the 2–3 km height region. We found that reff was 0.3–0.4 μm, ω at 532 nm ranged from 0.63 to 0.88 and m ranged from 1.45 + 0.015i to 1.56 + 0.05i, in good accordance with in situ aircraft measurements. The final data set of the aerosol microphysical properties along with the water vapor and temperature profiles were incorporated into the ISORROPIA model to infer an in situ aerosol composition consistent with the retrieved m and ω values. The retrieved aerosol chemical composition in the 2–3 km height region gave a variable range of sulfate (0–60%) and organic carbon (OC) content (0–50%), although the OC content increased (up to 50%) and the sulfate content dropped (up to 30%) around 3 km height; in connection with the retrieved low ω value (0.63), indicates the presence of absorbing biomass burning smoke mixed with urban haze. Finally, the retrieved aerosol microphysical properties were compared with column-integrated sunphotometer data.

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Multi-wavelength Raman lidar, sun photometric and aircraft measurements in combination with inversion models for the estimation of the aerosol optical and physico-chemical properties over Athens, Greece

Atmospheric Measurement Techniques ◽

10.5194/amt-5-1793-2012 ◽

2012 ◽

Vol 5 (7) ◽

pp. 1793-1808 ◽

Cited By ~ 27

Author(s):

R. E. Mamouri ◽

A. Papayannis ◽

V. Amiridis ◽

D. Müller ◽

P. Kokkalis ◽

...

Keyword(s):

Water Vapor ◽

Chemical Properties ◽

Urban Site ◽

Aircraft Measurements ◽

Raman Lidar ◽

Lidar System ◽

Aerosol Composition ◽

Microphysical Properties ◽

Multi Wavelength

Abstract. A novel procedure has been developed to retrieve, simultaneously, the optical, microphysical and chemical properties of tropospheric aerosols with a multi-wavelength Raman lidar system in the troposphere over an urban site (Athens, Greece: 37.9° N, 23.6° E, 200 m a.s.l.) using data obtained during the European Space Agency (ESA) THERMOPOLIS project, which took place between 15–31 July 2009 over the Greater Athens Area (GAA). We selected to apply our procedure for a case study of intense aerosol layers that occurred on 20–21 July 2009. The National Technical University of Athens (NTUA) EOLE 6-wavelength Raman lidar system has been used to provide the vertical profiles of the optical properties of aerosols (extinction and backscatter coefficients, lidar ratio) and the water vapor mixing ratio. An inversion algorithm was used to derive the mean aerosol microphysical properties (mean effective radius (reff), single-scattering albedo ω) and mean complex refractive index (m)) at selected heights in the 2–3 km height region. We found that reff was 0.14–0.4 (±0.14) μm, ω was 0.63–0.88 (±0.08) (at 532 nm) and m ranged from 1.44 (±0.10) + 0.01 (±0.01)i to 1.55 (±0.12) + 0.06 (±0.02)i, in good agreement (only for the reff values) with in situ aircraft measurements. The water vapor and temperature profiles were incorporated into the ISORROPIA II model to propose a possible in situ aerosol composition consistent with the retrieved m and ω values. The retrieved aerosol chemical composition in the 2–3 km height region gave a variable range of sulfate (0–60%) and organic carbon (OC) content (0–50%), although the OC content increased (up to 50%) and the sulfate content dropped (up to 30%) around 3 km height; the retrieved low ω value (0.63), indicates the presence of absorbing biomass burning smoke mixed with urban haze. Finally, the retrieved aerosol microphysical properties were compared with column-integrated sun photometer CIMEL data.

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Characterization of Aerosol Size and Microphysical Properties from Multi-Wavelength Raman Lidar Measurements: Inter-Comparison with in Situ Sensors Onboard the ATR 42 in the Framework of HyMEX-SOP1

EPJ Web of Conferences ◽

10.1051/epjconf/202023702009 ◽

2020 ◽

Vol 237 ◽

pp. 02009

Author(s):

Benedetto De Rosa ◽

Paolo Di Girolamo ◽

Donato Summa ◽

Dario Stellitano

Keyword(s):

Hydrological Cycle ◽

Aerosol Layer ◽

Raman Lidar ◽

Microphysical Properties ◽

Lidar Measurements ◽

Retrieval Scheme ◽

Research Aircraft ◽

Multi Wavelength ◽

In Situ Sensors

This extended abstract reports measurements that were carried out by the Raman lidar system BASIL in the frame of the Hydrological Cycle in the Mediterranean Experiment – Special Observation Period 1 (HyMeX-SOP1). A specific case study was selected revealing the presence of variable aerosol properties at different altitudes. Specifically, Raman lidar measurements on 02 October 2012 reveal the presence of two distinct aerosol layers, a lower one extending up to ~3 km and an upper one extending from 3.5 km to 4.7 km. Aerosol and size microphysical properties are determined from multi-wavelength measurements of particle backscattering and extinction profiles based on the application of a retrieval scheme which employs Tikhonov’s inversion with regularization. Inversion results suggest a size distribution with the presence, in both the lower and upper aerosol layer, of two particle modes (a fine mode, with a radius of ~0.2 μm, and a coarse mode, with radii in the range 2-4 μm), volume concentration values of 2-4 mm3cm-3 and effective radii in the range 0.2-0.6 μm. This effort benefited from the dedicated flights of the French research aircraft ATR42, equipped with a variety of in situ sensors for measuring aerosol/cloud size and microphysical properties. Aerosol size and microphysical properties retrieved from multi-wavelength Raman lidar measurements were compared with simultaneous and co-located in-situ measurements.

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Determination of aerosol size and microphiysical proprierties based on multi-wavelength raman lidar measurements in the framework of HyMeX-SOP1

10.5194/egusphere-egu2020-17218 ◽

2020 ◽

Author(s):

Benedetto De Rosa ◽

Paolo Di Girolamo ◽

Donato Summa

Keyword(s):

Hydrological Cycle ◽

Radiation Budget ◽

Aerosol Layer ◽

Raman Lidar ◽

Good Opportunity ◽

Microphysical Properties ◽

Lidar Measurements ◽

Multi Wavelength ◽

In Situ Sensors

Tropospheric aerosols&#160; are a fundamental component of the Earth&#8217;s radiation budget. In order to properly estimate their direct and indirect effect, accurate measurements of aerosol size and microphysical properties are required.A limited number of techniques are presently available and capable to provide these measurements.Multi-wavelength Raman lidars Raman lidars have strong potential. However,theireffectiveness and reliability of need to be assessed and verified against independent measurements.This abstract reports measurements that were carried out by the Raman lidar system BASIL in the frame of the Hydrological Cycle in the Mediterranean Experiment &#8211; Special Observation Period 1 (HyMeX-SOP1).The considered dataset represents a good opportunity to verify the quality of retrievals in terms of size and microphysical properties obtained from multi-wavelength Raman lidars.A specific case study was selected revealing the presence of variable aerosol properties at different altitudes. Specifically, Raman lidar measurements on 02 October 2012 show the presence of two distinct aerosol layers, a lower one extending up to ~3 km and an upper one extending from 3.5 km to 4.7 km. Aerosol and size microphysical properties are determined from multi-wavelength measurements of particle backscattering and extinction profiles based on the application of&#160; a retrieval scheme which employs Tikhonov&#8217;s inversion with regularization. Inversion results suggest a size distribution with the presence, in both the lower and upper aerosol layer, of two particle modes (a fine mode, with a radius of ~0.2 mm, and a coarse mode, with radii in the range 2-4 mm), volume concentration values of 2-4 mm3cm-3and effective radii in the&#160; range 0.2-0.6 mm.This effort benefited from the dedicated flights of the French research aircraft ATR42, equipped with a variety of in situ sensors for measuring aerosol/cloud size and microphysical properties. Aerosol size and microphysical properties retrieved from multi-wavelength Raman lidar measurements were compared with simultaneous and co-located in-situ measurements.

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Optical-microphysical properties of Saharan dust aerosols and composition relationship using a multi-wavelength Raman lidar, in situ sensors and modelling: a case study analysis

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-11-25473-2011 ◽

2011 ◽

Vol 11 (9) ◽

pp. 25473-25516 ◽

Cited By ~ 1

Author(s):

A. Papayannis ◽

R. E. Mamouri ◽

V. Amiridis ◽

E. Remoundaki ◽

G. Tsaknakis ◽

...

Keyword(s):

Refractive Index ◽

Saharan Dust ◽

Dust Particles ◽

Raman Lidar ◽

Dust Event ◽

Aerosol Composition ◽

Data Set ◽

Optical Extinction ◽

Microphysical Properties

Abstract. A strong Saharan dust event occurred over the city of Athens, Greece (37.9° N, 23.6° E) between 27 March and 3 April 2009. The BSC-DREAM8b model was used to forecast the dust event and to provide the vertical profiles of the aerosol concentration. Due to mixture of dust particles with low clouds during most of the reported period, the dust event could be followed by the National Technical University of Athens (NTUA) 6-wavelength Raman lidar system only during the unclouded day of 2 April 2009. The lidar data obtained were used to retrieve the vertical profile of the optical (extinction and backscatter coefficients) properties of aerosols in the troposphere. Additionally, a retrieval technique representing dust as a mixture of spheres and spheroids was used to derive the mean aerosol dust microphysical properties (mean and effective radius, number, surface and volume density, and mean refractive index) in different layers between 1.8 and 3.5 km a.s.l. The final data set of the aerosol optical and microphysical properties along with the water vapor profiles obtained by Raman lidar were incorporated into the ISORROPIA II model to infer an in situ aerosol composition consistent with the retrieved refractive index values. PM10 concentrations levels, PM10 composition results and SEM-EDX (Scanning Electron Microscope-Energy Dispersive X-ray) analysis results on sizes and mineralogy of particles from samples during the Saharan dust transport event were used to evaluate the retrieval.

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Retrieval of Dust Microphysical Properties

EPJ Web of Conferences ◽

10.1051/epjconf/202023708019 ◽

2020 ◽

Vol 237 ◽

pp. 08019

Author(s):

Böckmann Christine ◽

Samaras Stefanos ◽

Haarig Moritz

Keyword(s):

Long Range ◽

Long Range Transport ◽

Raman Lidar ◽

Dust Event ◽

Lidar System ◽

Microphysical Properties ◽

Range Transport ◽

Multi Wavelength ◽

Lidar Ratio ◽

Analyze Data

An intense mineral dust event from the Saharan desert was observed over the Island of Barbados after a long-range transport over the Atlantic Ocean during SALTRACE Campaign in June 2014. We analyze data from a multi-wavelength Raman-lidar system of Leibniz Institute for Tropospheric Research (TROPOS) called BERTHA (Back- scatter Extinction lidar Ratio Temperature Humidity profiling Apparatus) to derive the aerosol microphysical properties of the inspected layer via regularization using the software SphInX (Spheroidal Inversion eXperiments). These parameters were found to be within credible ranges.

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CADEX and beyond: Installation of a new PollyXT site in Dushanbe

E3S Web of Conferences ◽

10.1051/e3sconf/20199902010 ◽

2019 ◽

Vol 99 ◽

pp. 02010

Author(s):

Ronny Engelmann ◽

Julian Hofer ◽

Abduvosit N. Makhmudov ◽

Holger Baars ◽

Karsten Hanbuch ◽

...

Keyword(s):

Asian Dust ◽

Raman Lidar ◽

Technical Institute ◽

Lidar System ◽

Microphysical Properties ◽

Source Regions ◽

Central Asian ◽

Lidar Measurements ◽

Academy Of Sciences

During the 18-month Central Asian Dust Experiment we conducted continuous lidar measurements at the Physical Technical Institute of the Academy of Sciences of Tajikistan in Dushanbe between 2015 and 2016. Mineral dust plumes from various source regions have been observed and characterized in terms of their occurrence, and their optical and microphysical properties with the Raman lidar PollyXT. Currently a new container-based lidar system is constructed which will be installed for continuous long-term measurements in Dushanbe.

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Multi-Sensor Observation of a Saharan Dust Outbreak over Transylvania, Romania in April 2019

Atmosphere ◽

10.3390/atmos11040364 ◽

2020 ◽

Vol 11 (4) ◽

pp. 364 ◽

Cited By ~ 1

Author(s):

Nicolae Ajtai ◽

Horațiu Ștefănie ◽

Alexandru Mereuță ◽

Andrei Radovici ◽

Camelia Botezan

Keyword(s):

Complex Analysis ◽

Remote Sensing Data ◽

Ground Level ◽

Global Scale ◽

Saharan Dust ◽

Back Trajectories ◽

Microphysical Properties ◽

Multi Wavelength ◽

Degree Of Certainty

Mineral aerosols are considered to be the second largest source of natural aerosol, the Saharan desert being the main source of dust at global scale. Under certain meteorological conditions, Saharan dust can be transported over large parts of Europe, including Romania. The aim of this paper is to provide a complex analysis of a Saharan dust outbreak over the Transylvania region of Romania, based on the synergy of multiple ground-based and satellite sensors in order to detect the dust intrusion with a higher degree of certainty. The measurements were performed during the peak of the outbreak on April the 24th 2019, with instruments such as a Cimel sun-photometer and a multi-wavelength Raman depolarization lidar, together with an in-situ particle counter measuring at ground level. Remote sensing data from MODIS sensors on Terra and Aqua were also analyzed. Results show the presence of dust aerosol layers identified by the multi-wavelength Raman and depolarization lidar at altitudes of 2500–4000 m, and 7000 m, respectively. The measured optical and microphysical properties, together with the HYSPLIT back-trajectories, NMMB/BSC dust model, and synoptic analysis, confirm the presence of lofted Saharan dust layers over Cluj-Napoca, Romania. The NMMB/BSC dust model predicted dust load values between 1 and 1.5 g/m2 over Cluj-Napoca at 12:00 UTC for April the 24th 2019. Collocated in-situ PM monitoring showed that dry deposition was low, with PM10 and PM2.5 concentrations similar to the seasonal averages for Cluj-Napoca.

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Diffuse sunlight based calibration of the water vapor channel in the upc raman lidar

EPJ Web of Conferences ◽

10.1051/epjconf/201817605035 ◽

2018 ◽

Vol 176 ◽

pp. 05035

Author(s):

Constantino Muñoz-Porcar ◽

Adolfo Comeron ◽

Michaël Sicard ◽

Ruben Barragan ◽

David Garcia-Vizcaino ◽

...

Keyword(s):

Water Vapor ◽

Raman Scattering ◽

Calibration Factor ◽

Raman Lidar ◽

Lidar System ◽

System Parameters ◽

Vapor Channel ◽

Technical University

A method for determining the calibration factor of the water vapor channel of a Raman lidar, based on zenith measurements of diffuse sunlight and on assumptions regarding some system parameters and Raman scattering models, has been applied to the lidar system of Universitat Politècnica de Catalunya (UPC; Technical University of Catalonia, Spain). Results will be analyzed in terms of stability and comparison with typical methods relying on simultaneous radiosonde measurements.

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