We present an inversion algorithm for the retrieval of particle size distribution parameters, i.e., mean (effective) radius, number, surface area, and volume concentration, complex refractive index from multiwavelength lidar data. In contrast to classical Tikhonov method, which accepts only that solution discrepancy reaches its global minimum, in our we perform averaging solutions vicinity this minimum. This stabilizes underlying ill-posed inverse problem, particularly with respect number...

We report on the feasibility of deriving microphysical parameters bimodal particle size distributions from Mie-Raman lidar based a triple Nd:YAG laser. Such an instrument provides backscatter coefficients at 355, 532, and 1064 nm extinction 355 532 nm. The inversion method employed is Tikhonov’s with regularization. Special attention has been paid to extend range for which this scheme works ∼10 μm, makes algorithm applicable large particles, e.g., investigations concerning hygroscopic growth...

This paper focuses on optical and microphysical properties of long‐range transported biomass burning (BB) aerosols their variation with atmospheric evolution (ageing), as observed by a multiwavelength Raman lidar, part EARLINET (European Aerosol LIdar NETwork). Chemical analysis the aerosol was done using colocated mass spectrometer (AMS). One relevant parameter for ageing process is Ångström exponent. In our study, we find that it decreases from 2 fresh to 1.4–0.5 aged smoke particles. The...

Abstract. West Africa and the adjacent oceanic regions are very important locations for studying dust properties their influence on weather climate. The SHADOW (study of SaHAran Dust Over Africa) campaign is performing a multiscale multilaboratory study aerosol dynamics using set in situ remote sensing instruments at an observation site located IRD (Institute Research Development) Mbour, Senegal (14° N, 17° W). In this paper, we present results lidar measurements performed during first phase...

Multiwavelength (MW) Raman lidars have demonstrated their potential to profile particle parameters; however, until now, the physical models used in retrieval algorithms for processing MW lidar data been predominantly based on Mie theory. This approach is applicable modeling of light scattering by spherically symmetric particles only and does not adequately reproduce generally nonspherical desert dust particles. Here we present an algorithm a model randomly oriented spheroids inversion...

Abstract. We present measurements acquired by the world's first airborne 3 backscatter (β) + 2 extinction (α) High Spectral Resolution Lidar (HSRL-2). HSRL-2 measures particle coefficients at 355, 532, and 1064 nm, 355 532 nm. The instrument has been developed NASA Langley Research Center. was operated during Phase 1 of Department Energy (DOE) Two-Column Aerosol Project (TCAP) in July 2012. observed pollution outflow from northeastern coast US out over western Atlantic Ocean. ratios were...

Abstract The feasibility of using a multiwavelength Mie–Raman lidar based on tripled Nd:YAG laser for profiling aerosol physical parameters in the planetary boundary layer (PBL) under varying conditions relative humidity (RH) is studied. quantifies three backscattering and two extinction coefficients from these optical data particle such as concentration, size, complex refractive index are retrieved through inversion with regularization. column-integrated, lidar-derived compared results...

Abstract. An algorithm for linear estimation of aerosol bulk properties such as particle volume, effective radius and complex refractive index from multiwavelength lidar measurements is presented. The approach uses the fact that total concentration can well be approximated a combination characteristics measured by multi-wavelength lidar. Therefore, estimated without need to derive size distribution, which entails more sophisticated procedures. definition coefficients required estimates based...

We present for the first time vertical profiles of microphysical properties pure mineral dust (largely unaffected by any other aerosol types) on basis inversion optical data collected with multiwavelength polarization Raman lidar. The were taken during Saharan Mineral Dust Experiment (SAMUM) in Morocco 2006. also investigated two cases mixed dust-smoke plumes second SAMUM field campaign that took place Republic Cape Verde 2008. Following experience Aerosol Robotic Network (AERONET), is...

Abstract. We present a detailed evaluation of remotely sensed aerosol microphysical properties obtained from an advanced, multi-wavelength high-spectral-resolution lidar (HSRL-2) during the 2013 NASA DISCOVER-AQ field campaign. Vertically resolved retrievals fine-mode number, surface-area, and volume concentration as well effective radius are compared to 108 collocated, airborne in situ measurement profiles wintertime San Joaquin Valley, California, summertime Houston, Texas. An algorithm...

Abstract. The multi-wavelength lidar technique was applied to the study of a smoke event near Washington, DC on 26–28 August 2013. Satellite observations combined with transport model predictions imply that plume originated mainly from Wyoming/Idaho forest fires and its transportation took approximately 5 days. NASA Goddard Space Flight Center (GSFC) Mie–Raman used measure particle intensive parameters such as extinction backscatter Ångström exponents together ratios at 355 532 nm...

Abstract. We present a summary on the current status of two inversion algorithms that are used in EARLINET (European Aerosol Research Lidar Network) for data collected with multiwavelength Raman lidars. These instruments measure backscatter coefficients at 355, 532, and 1064 nm, extinction 355 532 nm. Development these started 2000 when was founded. The based manually controlled optical which allows detailed sensitivity studies. allow us to derive particle effective radius as well volume...

Abstract. Observations of multiwavelength Mie–Raman lidar taken during the SHADOW field campaign are used to analyze a smoke–dust episode over West Africa on 24–27 December 2015. For case considered, dust layer extended from ground up approximately 2000 m while elevated smoke occurred in 2500–4000 range. The profiles measured backscattering, extinction coefficients, and depolarization ratios compared with vertical distribution aerosol parameters provided by Modern-Era Retrospective Analysis...

We present an investigation of some important mathematical and numerical features related to the retrieval microphysical parameters [complex refractive index, single-scattering albedo, effective radius, total number, surface area, volume concentrations] ambient aerosol particles using multiwavelength Raman or high-spectral-resolution lidar. Using simple examples, we prove non-uniqueness inverse solution be major source difficulties. Some theoretically possible ways partially compensating for...

The multiwavelength Raman lidar technique in combination with sophisticated inversion algorithms has been recognized as a new tool for deriving information about the microphysical properties of atmospheric aerosols. input optical parameter sets, provided by respective aerosol lidars, are at theoretical lower limit which these work properly. For that reason there is ongoing intense discussion accuracy methods and possibility simultaneous retrieval particle size distribution complex refractive...

Abstract. In this work we study the effects of systematic and random errors on inversion multiwavelength (MW) lidar data using well-known regularization technique to obtain vertically resolved aerosol microphysical properties. The software implementation used here was developed at Physics Instrumentation Center (PIC) in Troitsk (Russia) conjunction with NASA/Goddard Space Flight Center. Its applicability Raman systems based backscattering measurements three wavelengths (355, 532 1064 nm)...

Abstract. The results of the application linear estimation technique to multiwavelength Raman lidar measurements performed during summer 2011 in Greenbelt, MD, USA, are presented. We demonstrate that lidars capable not only providing vertical profiles particle properties but also revealing spatio-temporal evolution aerosol features. nighttime 3β + 1α on 21 and 22 July were inverted distributions microphysical parameters, such as volume, number density, effective radius complex refractive...

We present the results of a feasibility study in which simple, automated, and unsupervised algorithm, we call arrange average is used to infer microphysical parameters (complex refractive index, effective radius, total number, surface area, volume concentrations) atmospheric aerosol particles. The algorithm uses backscatter coefficients at 355, 532, 1064 nm extinction 355 532 as input information. Testing based on synthetic optical data that are computed from prescribed monomodal particle...

Abstract. Vertical profiles of the optical (extinction and backscatter coefficients, lidar ratio Ångström exponent), microphysical (mean effective radius, mean refractive index, number concentration) geometrical properties as well mass concentration volcanic particles from Eyjafjallajökull eruption were retrieved at selected heights over Athens, Greece, using multi-wavelength Raman measurements performed during period 21–24 April 2010. Aerosol Robotic Network (AERONET) particulate columnar...

Abstract. The typical multiwavelength aerosol lidar data set for inversion of optical to microphysical parameters is composed three backscatter coefficients (β) at 355, 532, and 1064 nm two extinction (α) 355 532 nm. This combination referred as a 3β+2α or 3+2 set. sufficient retrieving some important particle if the particles have spherical shape. Here, we investigate effect including linear depolarization ratio (δ) third input parameter data. algorithm generally not used measurements show...

Abstract. A strong Saharan dust event that occurred over the city of Athens, Greece (37.9° N, 23.6° E) between 27 March and 3 April 2009 was followed by a synergy three instruments: 6-wavelength Raman lidar, CIMEL sun-sky radiometer MODIS sensor. The BSC-DREAM model used to forecast simulate vertical profiles aerosol concentration. Due mixture particles with low clouds during most reported period, could be lidar only cloud-free day 2 2009. data obtained were retrieve profile optical...

Inversion with two-dimensional (2-D) regularization is a new methodology that can be used for the retrieval of profiles microphysical properties, e.g., effective radius and complex refractive index atmospheric particles from complete (or sections) optical particle properties. The are acquired multiwavelength Raman lidar. Previous simulations synthetic data have shown advantages in terms accuracy compared to our so-called classical one-dimensional (1-D) regularization, which method mostly...

Abstract. This work deals with the applicability of linear estimation technique (LE) to invert spectral measurements aerosol optical depth (AOD) provided by AERONET CIMEL sun photometers. The inversion particle properties using only direct-sun AODs allows evaluation parameters such as effective radius (reff) and columnar volume content (V) significantly better temporal resolution than operational algorithm which requires both direct sky radiance measurements. Sensitivity studies performed...

We evaluate the retrieval performance of automated, unsupervised inversion algorithm, Tikhonov Advanced Regularization Algorithm (TiARA), which is used for autonomous microphysical parameters anthropogenic and natural pollution particles.TiARA (version 1.0) has been developed in past 10 years builds on legacy a data-operator-controlled algorithm since 1998 analysis data from multiwavelength Raman lidar.The development TiARA driven by need to analyze (near) real time large volumes collected...