scholarly journals Dust resuspension under weak wind conditions: direct observations and model

2011 ◽  
Vol 11 (11) ◽  
pp. 31231-31263
Author(s):  
O. G. Chkhetiani ◽  
E. B. Gledzer ◽  
M. S. Artamonova ◽  
M. A. Iordanskii
Keyword(s):  
Mineral Dust ◽  
Fluid Dynamic ◽  
Temperature Drop ◽  
Ground Surface ◽  
Dust Aerosol ◽  
Direct Observations ◽  
Dust Resuspension ◽  
Thermal Layer ◽  
Weak Wind ◽  
Mass Concentrations

Abstract. Here we report the results of the direct observations of fine scale mineral dust aerosol carried out over extensive sand areas in desertificated lands of Kalmykia in 2007, 2009 and 2010 under conditions of weak wind and strong heating of the surface with near absence of saltation processes. Measurements show that the fine mineral dust aerosol in the chosen region constitutes a considerable fraction of the entire air aerosol in the atmospheric surface layer (in terms of both the number of particles and their mass). Data of fine aerosol mass concentrations are treated on the basis of physical model estimates obtained for fluid dynamic parameters in the viscous thermal boundary layer near the ground surface. The deviations of mass concentrations from background are linked to temperature drop in the thermal layer near the surface and the value of friction velocity.

scholarly journals Dust resuspension under weak wind conditions: direct observations and model

2012 ◽  
Vol 12 (11) ◽  
pp. 5147-5162 ◽  
Author(s):  
O. G. Chkhetiani ◽  
E. B. Gledzer ◽  
M. S. Artamonova ◽  
M. A. Iordanskii
Keyword(s):  
Friction Velocity ◽  
Mineral Dust ◽  
Fluid Dynamic ◽  
Temperature Drop ◽  
Ground Surface ◽  
Dust Aerosol ◽  
Direct Observations ◽  
Surface Deviations ◽  
Weak Wind ◽  
Mass Concentrations

Abstract. The results of direct observations of fine mineral dust aerosol (0.15–15 μm) were carried out on extensive sand areas in desertificated lands of Kalmykia in 2007, 2009, and 2010 under conditions of weak wind and strong heating of the surface, almost in the absence of saltation processes. These results show that the fine mineral dust aerosol (0.15–0.5 μm) in the region under consideration contributes considerably to the total aerosol content of the atmospheric surface layer. Data on the mass concentrations of fine aerosol are treated on the basis of physical model estimates obtained for fluid dynamic parameters in the viscous thermal boundary layer near the ground surface. Deviations of these mass concentrations from their background values are related to a temperature drop in the thermal layer at the surface and from the values of friction velocity. For small and moderate values of friction velocity, these mass concentrations increase proportionally to a temperature drop with an exponent of about 0.5, and, for high friction velocities, this exponent becomes negative (~−0.5), which implies a decrease in these concentrations with an increase in a temperature drop.

scholarly journals Role of sea surface temperature responses in simulation of the climatic effect of mineral dust aerosol

2011 ◽  
Vol 11 (12) ◽  
pp. 6049-6062 ◽  
Author(s):  
X. Yue ◽  
H. Liao ◽  
H. J. Wang ◽  
S. L. Li ◽  
J. P. Tang
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Radiative Forcing ◽  
Mineral Dust ◽  
Dust Aerosol ◽  
Sea Surface ◽  
Climatic Effect ◽  
Radiative Effects ◽  
Climate Simulations

Abstract. Mineral dust aerosol can be transported over the nearby oceans and influence the energy balance at the sea surface. The role of dust-induced sea surface temperature (SST) responses in simulations of the climatic effect of dust is examined by using a general circulation model with online simulation of mineral dust and a coupled mixed-layer ocean model. Both the longwave and shortwave radiative effects of mineral dust aerosol are considered in climate simulations. The SST responses are found to be very influential on simulated dust-induced climate change, especially when climate simulations consider the two-way dust-climate coupling to account for the feedbacks. With prescribed SSTs and dust concentrations, we obtain an increase of 0.02 K in the global and annual mean surface air temperature (SAT) in response to dust radiative effects. In contrast, when SSTs are allowed to respond to radiative forcing of dust in the presence of the dust cycle-climate interactions, we obtain a global and annual mean cooling of 0.09 K in SAT by dust. The extra cooling simulated with the SST responses can be attributed to the following two factors: (1) The negative net (shortwave plus longwave) radiative forcing of dust at the surface reduces SST, which decreases latent heat fluxes and upward transport of water vapor, resulting in less warming in the atmosphere; (2) The positive feedback between SST responses and dust cycle. The dust-induced reductions in SST lead to reductions in precipitation (or wet deposition of dust) and hence increase the global burden of small dust particles. These small particles have strong scattering effects, which enhance the dust cooling at the surface and further reduce SSTs.

A new generator for mineral dust aerosol production from soil samples in the laboratory: GAMEL

2014 ◽  
Vol 15 ◽  
pp. 319-334 ◽  
Author(s):  
Sandra Lafon ◽  
Stéphane C. Alfaro ◽  
Servanne Chevaillier ◽  
Jean Louis Rajot
Keyword(s):  
Mineral Dust ◽  
Soil Samples ◽  
Dust Aerosol

Water Interaction with Mineral Dust Aerosol: Particle Size and Hygroscopic Properties of Dust

2018 ◽  
Vol 2 (4) ◽  
pp. 376-386 ◽  
Author(s):  
Sara Ibrahim ◽  
Manolis N. Romanias ◽  
Laurent Y. Alleman ◽  
Mohamad N. Zeineddine ◽  
Giasemi K. Angeli ◽  
...  
Keyword(s):  
Particle Size ◽  
Aerosol Particle ◽  
Mineral Dust ◽  
Dust Aerosol ◽  
Water Interaction ◽  
Hygroscopic Properties ◽  
Aerosol Particle Size

Mineral dust resuspension under vibration: Onset conditions and the role of humidity

Particuology ◽  
2020 ◽  
Vol 50 ◽  
pp. 112-119
Author(s):  
F.J. Balladore ◽  
J.G. Benito ◽  
R.O. Uñac ◽  
A.M. Vidales
Keyword(s):  
Mineral Dust ◽  
Dust Resuspension

scholarly journals Hygroscopicity of Different Types of Aerosol Particles: Case Studies Using Multi-Instrument Data in Megacity Beijing, China

2020 ◽  
Vol 12 (5) ◽  
pp. 785 ◽  
Author(s):  
Tong Wu ◽  
Zhanqing Li ◽  
Jun Chen ◽  
Yuying Wang ◽  
Hao Wu ◽  
...  
Keyword(s):  
Enhancement Factor ◽  
Mineral Dust ◽  
Aerosol Particles ◽  
Dust Aerosol ◽  
Dust Particles ◽  
Chemical Components ◽  
Hygroscopic Growth ◽  
Microphysical Properties ◽  
Fine Mode ◽  
Fine Mode Aerosol

Water uptake by aerosol particles alters its light-scattering characteristics significantly. However, the hygroscopicities of different aerosol particles are not the same due to their different chemical and physical properties. Such differences are explored by making use of extensive measurements concerning aerosol optical and microphysical properties made during a field experiment from December 2018 to March 2019 in Beijing. The aerosol hygroscopic growth was captured by the aerosol optical characteristics obtained from micropulse lidar, aerosol chemical composition, and aerosol particle size distribution information from ground monitoring, together with conventional meteorological measurements. Aerosol hygroscopicity behaves rather distinctly for mineral dust coarse-mode aerosol (Case I) and non-dust fine-mode aerosol (Case II) in terms of the hygroscopic enhancement factor, f β ( R H , λ 532 ) , calculated for the same humidity range. The two types of aerosols were identified by applying the polarization lidar photometer networking method (POLIPHON). The hygroscopicity for non-dust aerosol was much higher than that for dust conditions with the f β ( R H , λ 532 ) being around 1.4 and 3.1, respectively, at the relative humidity of 86% for the two cases identified in this study. To study the effect of dust particles on the hygroscopicity of the overall atmospheric aerosol, the two types of aerosols were identified and separated by applying the polarization lidar photometer networking method in Case I. The hygroscopic enhancement factor of separated non-dust fine-mode particles in Case I had been significantly strengthened, getting closer to that of the total aerosol in Case II. These results were verified by the hygroscopicity parameter, κ (Case I non-dust particles: 0.357 ± 0.024; Case II total: 0.344 ± 0.026), based on the chemical components obtained by an aerosol chemical speciation instrument, both of which showed strong hygroscopicity. It was found that non-dust fine-mode aerosol contributes more during hygroscopic growth and that non-hygroscopic mineral dust aerosol may reduce the total hygroscopicity per unit volume in Beijing.

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