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Showing 1 to 20 of 32 for “"Mineral dust"”.
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Mineral dust lofting and interactions with cold pools
Convective dust storms, or haboobs, form when strong surface winds loft loose soils in convective storm outflow boundaries. Haboobs are a public safety hazard and can cause a near instantaneous loss of visibility, inimical air quality, and contribute significantly to regional dust and radiation …
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Heterogeneous Reactions of Nitric Acid and Dinitrogen Pentoxide on Mineral Dust Surfaces: A Knudsen Reactor Study
… and dinitrogen pentoxide with various authentic dust, mineral and clay mineral surfaces has been investigated my means of the Knudsen reactor techique at room temperature. Authentic dust surfaces from the Saharan, the Chinese and the Arizona dust regions were used as substrates, as were the …
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Cloud condensation nucleus activity comparison of dry- and wet-generated mineral dust aerosol : the significance of soluble material
This study examines the interaction of clay mineral particles and water vapor to determine the conditions required for cloud droplet formation. Droplet formation conditions are investigated for two common clay minerals, illite and sodium-rich montmorillonite, and an industrially derived sample, …
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Quantifying glacier melt enhancement due to dust deposition during the 2022 melt season. Tungnaárjökull glacier, South Iceland
… presence of light absorbing impurities such as mineral dust on glacier surfaces alters their reflective properties leading to a reduction in albedo, consequently increasing absorption of incoming solar radiation which further impacts the glacier surface mass balance (SMB). Icelandic glaciers …
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Development of a Knudsen Cell Reactor for Measuring the Uptake of Atmospheric Gases on Particulate Matter
Heterogeneous reactions between mineral dust aerosols and gas phase volatile organic compounds have the potential to impact important atmospheric chemical processes. However, little is known about the uptake and reactivity of volatile organic compounds on particulates found in the environment. A …
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Cavity ring down: Construction, validation and experiments measuring the optical extinction of pure clays and their mixtures with salts and carboxylic acids under a range of atmospherically relevant conditions
… unusual chemical and physical properties.</p><p>Mineral dust particles are a large fraction of the total aerosol mass and thus contribute extensively to the climate balance. Assessing this impact is complicated by the irregular shape and sheet-like structures of these species making them …
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Microphysics of atmospheric aerosols : phase transitions and cloud formation mechanisms
… We have also investigated the role of mineral dust and soot, major components of insoluble particulates in the atmosphere, as ice-nuclei. We have found mineral dust to be an effective ice nuclei but both fresh and aged soot do not promote ice nucleation in aqueous particles.
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Reconstructing atmospheric changes in monsoon regions using eolian dust
Mineral dust is generated in continental interiors and exported by winds to ocean basins, providing a sedimentary archive which is one of the few direct indicators we have of atmospheric circulation in the past. This archive can be utilized in regions of dust transport also affected by monsoons to …
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IODINE SPECIATION IN MARINE AEROSOL
… identified: polluted aerosol, clean seasalt and mineral dust. pH seems to play an important role in regulating iodine speciation. The formation of HOI and the reduction of iodate are driven by acidic conditions in polluted aerosol. In clean less acidic seasalt aerosol, a high iodine enrichment …
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Trace metals and nutrients in aerosols over the tropical and subtropical North Atlantic Ocean
… that the total elemental composition of the dust is close to average crustal composition and shows a high degree of consistency. Based on elemental composition data alone, dust collected on the cruise appears similar to dust collected at the CVAO. Zn and Pb are elevated above crustal values …
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Variability, origin and physical characteristics of dust aerosol in Iceland
… of the total particulate air pollution. Less industrialized and inhibited regions, such as deserts, can contribute remarkably to air pollution. Iceland is a good example of such areas. The trends in long-term dust activity in Iceland and results from the pioneer field experiments on dust …
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A machine-learning approach to aerosol classification for single-particle mass spectrometry
… types in four broad categories: fertile soils, mineral/metallic particles, biological, and all other aerosols using -40 common positive and negative spectral features. For this broad categorization, machine learning resulted in a classification accuracy of -93%. More complex models were …
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An experimental study of OH uptake by surfaces of tropospheric importance under dry and wet conditions
… for enhancement in OH reactivity with mineral dust surfaces under high humidity conditions. Mass spectra of the gas-phase species produced from the heterogeneous reaction of OH with NaCl were obtained in order to characterize the reaction products and the kinetic mechanism. Evidence for …
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The effectiveness of actively accumulating dust in rejuvenating soils and ecosystems in a super-humid, high weathering and leaching environment, West Coast, South Island, New Zealand
The deposition of mineral dust is an integral component of terrestrial and marine biogeochemical cycles. Dust is recognised as an important rejuvenator by supplying nutrients and unweathered mineral material to ecosystems. While deposition rates have been regularly quantified for terrestrial …
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Experimental Studies of the Heterogeneous Kinetics of OH Radicals with terbuthylazine, Adsorbed on Self- Synthesized SiO2 Particles, in a Temperature Controlled Aerosol Smog Chamber
… of terbuthylazine is less than 2 days on plain mineral dust.
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Concentration and Size Distribution of Microparticles in the NGRIP Ice Core (Central Greenland) during the Last Glacial Period
The concentration and size distribution of mineral microparticles were investigated in the deep North Greenland Ice Core Project (NGRIP) ice core. The measurements were accomplished using a novel, optical detector which is based on laser light attenuation by individual particles. The device works …
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Advances in the Hyperspectral Imaging Microscope Spectrometer Method, and Application for Measuring the Spectral Reflectance of Light Absorbing Aerosols from the South Cascades, Colorado Rockies, and Iceland
… aerosols (LAA), including black carbon, mineral dust and organics onto snow and glacier surfaces can be an even larger driver of melt in some regions (Skiles et al., 2012). Attempts to partition the relative contribution of different types of LAA to snow and glacier melt has been limited …
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Reconstructing atmospheric changes in Monsoon regions using eolian dust
Mineral dust is generated in continental interiors and exported by winds to ocean basins, providing a sedimentary archive which is one of the few direct indicators we have of atmospheric circulation in the past. This archive can be utilized in regions of dust transport also affected by monsoons to …
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Simulating and quantifying land-surface biogeochemical, hydrological, and biogeophysical processes using the Community Land Model version 4
… nitrogen-stock variations. Last but not least, mineral dust, a type of atmospheric aerosol, alters surface radiation/energy balance, and may act as cloud condensation nuclei to modify precipitation rates and eventually the hydrological cycle. Therefore, we were motivated to investigate these …
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