E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Special Issue "Advances in Studies of Atmospheric Aerosol and Clouds Using Remote Sensing Techniques"

Quicklinks

A special issue of Atmosphere (ISSN 2073-4433).

Deadline for manuscript submissions: closed (31 October 2012)

Special Issue Editor

Guest Editor
Dr. Alexander A. Kokhanovsky

EUMETSAT, Eumetsat Allee 1, D-64295 Darmstadt, Germany
Website | E-Mail
Interests: remote sensing; light scattering; radiative transfer; inverse problems; atmospheric optics; retrieval of aerosol and cloud properties from spaceborne observations

Special Issue Information

Dear Colleagues,

Various solid and liquid macroscopic particles (including cloud droplets and crystals)  reside in atmosphere.
They interact with atmospheric gases and influence both climate and human health. Therefore, it is of importance to develop new instrumentation and improve existing techniques for the determination of particulate matter vertical columns in atmosphere. The chemical composition of aerosol particles is also of a great interest.
The main subject of this issue is to discuss recent trends and results in the area of remote sensing of atmospheric aerosol and clouds using ground, airborne, shipborne, and satellite optical  instrumentation (in particular, spectrometers and radiometers). This requires the solution of inverse problem of the radiative transfer theory. Therefore, the papers dealing with various aspects of light scattering and radiative transfer in atmosphere are particularly welcome.

Dr. Alexander A. Kokhanovsky
Guest Editor

Keywords

  • aerosol
  • cloud
  • remote sensing
  • light scattering
  • radiative transfer
  • inverse problem
  • underlying surface reflectance
  • atmospheric correction

Published Papers (8 papers)

View options order results:
result details:
Displaying articles 1-8
Export citation of selected articles as:

Research

Open AccessArticle Spatial and Temporal Variations of Atmospheric Aerosol in Osaka
Atmosphere 2013, 4(2), 157-168; doi:10.3390/atmos4020157
Received: 15 February 2013 / Revised: 12 May 2013 / Accepted: 13 May 2013 / Published: 21 May 2013
Cited by 5 | PDF Full-text (391 KB) | HTML Full-text | XML Full-text
Abstract
It is well known that the aerosol distribution in Asia is complex due to both the increasing emissions of the anthropogenic aerosols associated with economic growth and the behavior of natural dusts. Therefore, detailed observations of atmospheric particles in Asian urban cities are
[...] Read more.
It is well known that the aerosol distribution in Asia is complex due to both the increasing emissions of the anthropogenic aerosols associated with economic growth and the behavior of natural dusts. Therefore, detailed observations of atmospheric particles in Asian urban cities are important. In this work, we focus on the spatial and temporal variations of atmospheric particles around Higashi-Osaka in Japan. Higashi-Osaka is located in the eastern part of Osaka, the second-largest city in Japan, and is famous for small- and medium-sized manufacturing enterprises. For this study, we placed various ground measurement devices around the Higashi-Osaka campus of Kinki University including a Cimel sunphotometer supported by NASA/AERONET (Aerosol robotics network), suspended particulate matter (SPM) sampler and LIDAR (light detection and ranging). Individual particle analyses with a SEM (scanning electron microscope)/EDX (energy-dispersive X-ray analyzer) show the temporal variations of particle properties, such as size, shape and components, during a dust event on 21 March 2010. The simultaneous measurement using a portable sun photometer with AERONET was conducted from April to November 2011. A comparison of the data at each site and the combination of the observed LIDAR data and model simulations indicate the difference in the transportation processes between dust and anthropogenic particles. We suppose this difference is attributed to the differences in the vertical aerosol profiles, where one aerosol is transported over Mount Ikoma and the other is blocked by it. Full article
Open AccessArticle Characterizing a New Surface-Based Shortwave Cloud Retrieval Technique, Based on Transmitted Radiance for Soil and Vegetated Surface Types
Atmosphere 2013, 4(1), 48-71; doi:10.3390/atmos4010048
Received: 19 December 2012 / Revised: 7 March 2013 / Accepted: 13 March 2013 / Published: 19 March 2013
PDF Full-text (1279 KB) | HTML Full-text | XML Full-text
Abstract
This paper presents an approach using the GEneralized Nonlinear Retrieval Analysis (GENRA) tool and general inverse theory diagnostics including the maximum likelihood solution and the Shannon information content to investigate the performance of a new spectral technique for the retrieval of cloud optical
[...] Read more.
This paper presents an approach using the GEneralized Nonlinear Retrieval Analysis (GENRA) tool and general inverse theory diagnostics including the maximum likelihood solution and the Shannon information content to investigate the performance of a new spectral technique for the retrieval of cloud optical properties from surface based transmittance measurements. The cumulative retrieval information over broad ranges in cloud optical thickness (τ), droplet effective radius (re), and overhead sun angles is quantified under two conditions known to impact transmitted radiation; the variability in land surface albedo and atmospheric water vapor content. Our conclusions are: (1) the retrieved cloud properties are more sensitive to the natural variability in land surface albedo than to water vapor content; (2) the new spectral technique is more accurate (but still imprecise) than a standard approach, in particular for τ between 5 and 60 and re less than approximately 20 μm; and (3) the retrieved cloud properties are dependent on sun angle for clouds of  from 5 to 10 and re < 10 μm, with maximum sensitivity obtained for an overhead sun. Full article
Figures

Open AccessArticle Dust Detection and Optical Depth Retrieval Using MSG‑SEVIRI Data
Atmosphere 2013, 4(1), 35-47; doi:10.3390/atmos4010035
Received: 2 November 2012 / Revised: 26 February 2013 / Accepted: 26 February 2013 / Published: 5 March 2013
Cited by 3 | PDF Full-text (408 KB) | HTML Full-text | XML Full-text
Abstract
Thanks to its observational frequency of 15 min, the Meteosat Second Generation (MSG) geostationary satellite offers a great potential to monitor dust storms. To explore this potential, an algorithm for the detection and the retrieval of dust aerosol optical properties has been tested.
[...] Read more.
Thanks to its observational frequency of 15 min, the Meteosat Second Generation (MSG) geostationary satellite offers a great potential to monitor dust storms. To explore this potential, an algorithm for the detection and the retrieval of dust aerosol optical properties has been tested. This is a multispectral algorithm based on visible and infrared data which has been applied to 15 case studies selected between 2007 and 2011. The algorithm has been validated in the latitude–longitude box between 30 and 50 degrees north, and −10 and 20 degrees east, respectively. Hereafter we present the obtained results that have been validated against Aerosol Robotic Network (AERONET) ground-based measurements and compared with the retrievals from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra and Aqua satellites. The dust aerosol optical depth variations observed at the AERONET sites are well reproduced, showing good correlation of about 0.77, and a root mean square difference within 0.08, and the spatial patterns retrieved by using the algorithm developed are in agreement with those observed by MODIS. Full article
Figures

Open AccessArticle Biomass Burning Aerosols Observed in Northern Finland during the 2010 Wildfires in Russia
Atmosphere 2013, 4(1), 17-34; doi:10.3390/atmos4010017
Received: 31 October 2012 / Revised: 4 February 2013 / Accepted: 19 February 2013 / Published: 28 February 2013
Cited by 7 | PDF Full-text (1066 KB) | HTML Full-text | XML Full-text
Abstract
A smoke plume originating from the massive wildfires near Moscow was clearly detected in northern Finland on 30 July 2010. Measurements made with remote sensing instruments demonstrated how the biomass burning aerosols affected the chemical and optical characteristics of the atmosphere in regions
[...] Read more.
A smoke plume originating from the massive wildfires near Moscow was clearly detected in northern Finland on 30 July 2010. Measurements made with remote sensing instruments demonstrated how the biomass burning aerosols affected the chemical and optical characteristics of the atmosphere in regions hundreds of kilometers away from the actual fires. In this study, we used MODIS, AIRS, CALIOP, PFR, ceilometers, FTS and Brewer data to quantify the properties of the transported smoke plume. In addition, in situ measurements of aerosol concentration (DMPS), absorption (aethalometer) and scattering (nephelometer) are presented. We found that due to the smoke plume in northern Finland, the daily averaged optical thickness of aerosols increased fourfold, and MODIS retrieved AOD as high as 4.5 for the thickest part of the plume. FTS measurements showed that CO concentration increased by 100% during the plume. CALIOP and ceilometer measurements revealed that the smoke plume was located close to the surface, below 3 km, and that the plume was not homogeneously mixed. In addition, in situ measurements showed that the scattering and absorption coefficients were almost 20 times larger in the smoke plume than on average, and that the number of particles larger than 320 nm increased 14-fold. Moreover, a comparison with in situ measurements recorded in eastern Finland on the previous day showed that the transport from eastern to northern Finland decreased the scattering coefficient, black carbon concentration, and total number concentration 0.5%/h, 1.5%/h and 2.0%/h, respectively. Full article
Open AccessArticle Exploration of a Polarized Surface Bidirectional Reflectance Model Using the Ground-Based Multiangle SpectroPolarimetric Imager
Atmosphere 2012, 3(4), 591-619; doi:10.3390/atmos3040591
Received: 25 October 2012 / Revised: 8 December 2012 / Accepted: 13 December 2012 / Published: 18 December 2012
Cited by 12 | PDF Full-text (1233 KB) | HTML Full-text | XML Full-text
Abstract
Accurate characterization of surface reflection is essential for retrieval of aerosols using downward-looking remote sensors. In this paper, observations from the Ground-based Multiangle SpectroPolarimetric Imager (GroundMSPI) are used to evaluate a surface polarized bidirectional reflectance distribution function (PBRDF) model. GroundMSPI is an eight-band
[...] Read more.
Accurate characterization of surface reflection is essential for retrieval of aerosols using downward-looking remote sensors. In this paper, observations from the Ground-based Multiangle SpectroPolarimetric Imager (GroundMSPI) are used to evaluate a surface polarized bidirectional reflectance distribution function (PBRDF) model. GroundMSPI is an eight-band spectropolarimetric camera mounted on a rotating gimbal to acquire pushbroom imagery of outdoor landscapes. The camera uses a very accurate photoelastic-modulator-based polarimetric imaging technique to acquire Stokes vector measurements in three of the instrument’s bands (470, 660, and 865 nm). A description of the instrument is presented, and observations of selected targets within a scene acquired on 6 January 2010 are analyzed. Data collected during the course of the day as the Sun moved across the sky provided a range of illumination geometries that facilitated evaluation of the surface model, which is comprised of a volumetric reflection term represented by the modified Rahman-Pinty-Verstraete function plus a specular reflection term generated by a randomly oriented array of Fresnel-reflecting microfacets. While the model is fairly successful in predicting the polarized reflection from two grass targets in the scene, it does a poorer job for two manmade targets (a parking lot and a truck roof), possibly due to their greater degree of geometric organization. Several empirical adjustments to the model are explored and lead to improved fits to the data. For all targets, the data support the notion of spectral invariance in the angular shape of the unpolarized and polarized surface reflection. As noted by others, this behavior provides valuable constraints on the aerosol retrieval problem, and highlights the importance of multiangle observations. Full article
Figures

Open AccessArticle Initial Assessment of the Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR)-Based Aerosol Retrieval: Sensitivity Study
Atmosphere 2012, 3(4), 495-521; doi:10.3390/atmos3040495
Received: 25 July 2012 / Revised: 17 September 2012 / Accepted: 9 October 2012 / Published: 24 October 2012
Cited by 4 | PDF Full-text (786 KB) | HTML Full-text | XML Full-text
Abstract
The Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) being developed for airborne measurements will offer retrievals of aerosol microphysical and optical properties from multi-angular and multi-spectral measurements of sky radiance and direct-beam sun transmittance. In this study, we assess the expected accuracy of
[...] Read more.
The Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) being developed for airborne measurements will offer retrievals of aerosol microphysical and optical properties from multi-angular and multi-spectral measurements of sky radiance and direct-beam sun transmittance. In this study, we assess the expected accuracy of the 4STAR-based aerosol retrieval and its sensitivity to major sources of anticipated perturbations in the 4STAR measurements. The major anticipated perturbations are (1) an apparent enhancement of sky radiance at small scattering angles associated with the necessarily compact design of the 4STAR and (2) an offset (i.e., uncertainty) of sky radiance calibration independent of scattering angle. The assessment is performed through application of the operational AERONET aerosol retrieval and constructed synthetic 4STAR-like data. Particular attention is given to the impact of these perturbations on the broadband fluxes and the direct aerosol radiative forcing. The results from this study suggest that limitations in the accuracy of 4STAR-retrieved particle size distributions and scattering phase functions have diminished impact on the accuracy of retrieved bulk microphysical parameters, permitting quite accurate retrievals of properties including the effective radius (up to 10%, or 0.03), and the radiatively important optical properties, such as the asymmetry factor (up to 4%, or ±0.02) and single-scattering albedo (up to 6%, or ±0.04). Also, the obtained results indicate that the uncertainties in the retrieved aerosol optical properties are quite small in the context of the calculated fluxes and direct aerosol radiative forcing (up to 15%, or 3 W∙m−2). Full article
Open AccessArticle Development of a Ground Based Remote Sensing Approach for Direct Evaluation of Aerosol-Cloud Interaction
Atmosphere 2012, 3(4), 468-494; doi:10.3390/atmos3040468
Received: 13 June 2012 / Revised: 27 August 2012 / Accepted: 21 September 2012 / Published: 17 October 2012
Cited by 3 | PDF Full-text (1325 KB) | HTML Full-text | XML Full-text
Abstract
The possible interaction and modification of cloud properties due to aerosols is one of the most poorly understood mechanisms within climate studies, resulting in the most significant uncertainty as regards radiation budgeting. In this study, we explore direct ground based remote sensing methods to
[...] Read more.
The possible interaction and modification of cloud properties due to aerosols is one of the most poorly understood mechanisms within climate studies, resulting in the most significant uncertainty as regards radiation budgeting. In this study, we explore direct ground based remote sensing methods to assess the Aerosol-Cloud Indirect Effect directly, as space-borne retrievals are not directly suitable for simultaneous aerosol/cloud retrievals. To illustrate some of these difficulties, a statistical assessment of existing multispectral imagers on geostationary (e.g., GOES)/Moderate Resolution Imaging Spectroradiometer (MODIS) satellite retrievals of the Cloud Droplet Effective Radius (Reff) showed significant biases especially at larger solar zenith angles, further motivating the use of ground based remote sensing approaches. In particular, we discuss the potential of using a combined Microwave Radiometer (MWR)—Multi-Filter Rotating Shadowband Radiometer (MFRSR) system for real-time monitoring of Cloud Optical Depth (COD) and Cloud Droplet Effective Radius (Reff), which are combined with aerosol vertical properties from an aerosol lidar. An iterative approach combining the simultaneous observations from MFRSR and MWR are used to retrieve the COD and Reff for thick cloud cases and are extensively validated using the DoE Southern Great Plains (SGP) retrievals as well as regression based parameterized model retrievals. In addition, we account for uncertainties in background aerosol, surface albedo and the combined measurement uncertainties from the MWR and MFRSR in order to provide realistic uncertainty estimates, which is found to be ~10% for the parameter range of interest in Aerosol-Cloud Interactions. Finally, we analyze a particular case of possible aerosol-cloud interaction described in the literature at the SGP site and demonstrate that aerosol properties obtained at the surface can lead to inconclusive results in comparison to lidar-derived aerosol properties near the cloud base. Full article
Open AccessArticle A Polarized Atmospheric Radiative Transfer Model for Calculations of Spectra of the Stokes Parameters of Shortwave Radiation Based on the Line-by-Line and Monte Carlo Methods
Atmosphere 2012, 3(4), 451-467; doi:10.3390/atmos3040451
Received: 1 August 2012 / Revised: 20 September 2012 / Accepted: 26 September 2012 / Published: 10 October 2012
Cited by 5 | PDF Full-text (833 KB) | HTML Full-text | XML Full-text
Abstract
This paper presents a new version of radiative transfer model called the Fast Line-by-Line Model (FLBLM), which is based on the Line-by-Line (LbL) and Monte Carlo (MC) methods and rigorously treats particulate and molecular scattering alongside absorption. The advantage of this model consists
[...] Read more.
This paper presents a new version of radiative transfer model called the Fast Line-by-Line Model (FLBLM), which is based on the Line-by-Line (LbL) and Monte Carlo (MC) methods and rigorously treats particulate and molecular scattering alongside absorption. The advantage of this model consists in the use of the line-by-line model that allows for the computing of high-resolution spectra quite quickly. We have developed the model by taking into account the polarization state of light and carried out some validations by comparison against benchmark results. FLBLM calculates the Stokes parameters spectra of shortwave radiation in vertically inhomogeneous atmospheres. This update makes the model applicable for the assessment of cloud and aerosol influence on radiances as measured by the SW high-resolution polarization spectrometers. In sample results we demonstrate that the high-resolution spectra of the Stokes parameters contain more detailed information about clouds and aerosols than the medium- and low-resolution spectra wherein lines are not resolved. The presented model is rapid enough for many practical applications (e.g., validations) and might be useful especially for the remote sensing. FLBLM is suitable for development of the reliable technique for retrieval of optical and microphysical properties of clouds and aerosols from high-resolution satellites data. Full article

Journal Contact

MDPI AG
Atmosphere Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
atmosphere@mdpi.com
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to Atmosphere
Back to Top