Next Issue
Volume 4, June
Previous Issue
Volume 3, December
 
 

Atmosphere, Volume 4, Issue 1 (March 2013) – 4 articles , Pages 1-71

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Select all
Export citation of selected articles as:
1279 KiB  
Article
Characterizing a New Surface-Based Shortwave Cloud Retrieval Technique, Based on Transmitted Radiance for Soil and Vegetated Surface Types
by Odele Coddington, Peter Pilewskie, K. Sebastian Schmidt, Patrick J. McBride and Tomislava Vukicevic
Atmosphere 2013, 4(1), 48-71; https://doi.org/10.3390/atmos4010048 - 19 Mar 2013
Cited by 8 | Viewed by 7088
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
Show Figures

Graphical abstract

408 KiB  
Article
Dust Detection and Optical Depth Retrieval Using MSG‑SEVIRI Data
by Filomena Romano, Elisabetta Ricciardelli, Domenico Cimini, Francesco Di Paola and Mariassunta Viggiano
Atmosphere 2013, 4(1), 35-47; https://doi.org/10.3390/atmos4010035 - 05 Mar 2013
Cited by 19 | Viewed by 7273
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
Show Figures

Graphical abstract

1066 KiB  
Article
Biomass Burning Aerosols Observed in Northern Finland during the 2010 Wildfires in Russia
by Tero Mielonen, Veijo Aaltonen, Heikki Lihavainen, Antti-Pekka Hyvärinen, Antti Arola, Mika Komppula and Rigel Kivi
Atmosphere 2013, 4(1), 17-34; https://doi.org/10.3390/atmos4010017 - 28 Feb 2013
Cited by 18 | Viewed by 7216
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
Show Figures

Figure 1

1100 KiB  
Article
A Comparison of the Mineral Dust Absorptive Properties between Two Asian Dust Events
by Timothy Logan, Baike Xi and Xiquan Dong
Atmosphere 2013, 4(1), 1-16; https://doi.org/10.3390/atmos4010001 - 28 Jan 2013
Cited by 25 | Viewed by 5960
Abstract
Asian dust events are generated by deep convection from strong low pressure systems that form over mineral dust source regions. This study compares the mineral dust optical properties of two strong Asian dust events from the winter (December 2007) and spring (March 2010) [...] Read more.
Asian dust events are generated by deep convection from strong low pressure systems that form over mineral dust source regions. This study compares the mineral dust optical properties of two strong Asian dust events from the winter (December 2007) and spring (March 2010) seasons using AERONET retrieved parameters from three sites along the dust event path: SACOL (dust source region), Xianghe (downwind mixed aerosol region), and Taihu (downwind pollution region). The parameters include: aerosol effective radius, optical depth (t), absorptive optical depth (tabs), their respective wavelength dependences or Angstrom exponents (a and aabs), and the spectral single scattering albedo (wo(λ)). The a440–870 values in both cases do not exceed 0.62 indicating coarse mode particle dominance at all three sites. The winter case is shown to have carbonaceous influences at all three sites as given by aabs440–870 between 1.3 and 1.8 with strong spectral tabs absorption. The spring case is more dust dominant with aabs440–870 of 1.7–2.5 (noting that the largest value occurred at Taihu) with strong tabs absorption primarily in the visible wavelengths. Comparison studies between the observed and theoretically calculated wo(λ) for the winter and spring cases have shown an excellent agreement except for the winter case at Taihu due to pollution influences. The comparison studies also suggest that wo(λ) is more sensitive to particle absorptive properties rather than particle size. The sharp increase in the aerosol radiative effect (ARE) during the dust events with AREBOA > ARETOA suggests a stronger aerosol cooling effect at the surface than at the TOA. Full article
Show Figures

Graphical abstract

Previous Issue
Next Issue
Back to TopTop