Relevant bibliographies by topics / Atmospheric dust transport

Academic literature on the topic 'Atmospheric dust transport'

Author: Grafiati
Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Atmospheric dust transport"

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Schepanski, Kerstin, Marc Mallet, Bernd Heinold, and Max Ulrich. "North African dust transport toward the western Mediterranean basin: atmospheric controls on dust source activation and transport pathways during June–July 2013." Atmospheric Chemistry and Physics 16, no. 22 (November 15, 2016): 14147–68. http://dx.doi.org/10.5194/acp-16-14147-2016.

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Abstract. Dust transported from north African source region toward the Mediterranean basin and Europe is a ubiquitous phenomenon in the Mediterranean region. Winds formed by large-scale pressure gradients foster dust entrainment into the atmosphere over north African dust source regions and advection of dust downwind. The constellation of centers of high and low pressure determines wind speed and direction, and thus the chance for dust emission over northern Africa and transport toward the Mediterranean. We present characteristics of the atmospheric dust life cycle determining dust transport toward the Mediterranean basin with focus on the ChArMEx (Chemistry-Aerosol Mediterranean Experiment) special observation period in June and July 2013 using the atmosphere–dust model COSMO-MUSCAT (COSMO: COnsortium for Small-scale MOdeling; MUSCAT: MUltiScale Chemistry Aerosol Transport Model). Modes of atmospheric circulation are identified from empirical orthogonal function (EOF) analysis of the geopotential height at 850 hPa and compared to EOFs calculated from 1979–2015 ERA-Interim reanalysis. Two different phases are identified from the first EOF, which in total explain 45 % of the variance. They are characterized by the propagation of the subtropical ridge into the Mediterranean basin, the position of the Saharan heat low and the predominant Iberian heat low, and discussed illustrating a dipole pattern for enhanced (reduced) dust emission fluxes, stronger (weaker) meridional dust transport, and consequent increased (decreased) atmospheric dust concentrations and deposition fluxes. In the event of a predominant high-pressure zone over the western and central Mediterranean (positive phase), a hot spot in dust emission flux is evident over the Grand Erg Occidental, and a reduced level of atmospheric dust loading occurs over the western Mediterranean basin. The meridional transport in northward direction is reduced due to prevailing northerly winds. In case of a predominant heat low trough linking the Iberian and the Saharan heat low (negative phase), meridional dust transport toward the western Mediterranean is increased due to prevailing southerly winds resulting in an enhanced atmospheric dust loading over the western Mediterranean. Altogether, results from this study illustrate the relevance of knowing dust source location and characteristics in concert with atmospheric circulation. The study elaborates on the question of the variability of summertime dust transport toward the Mediterranean and Europe with regard to atmospheric circulation conditions controlling dust emission and transport routes of Saharan dust, exemplarily for the 2-month period of June–July 2013. Ultimately, outcomes from this study contribute to the understanding of the variance in dust transport into a populated region.
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Toth III, Joseph R., Siddharth Rajupet, Henry Squire, Blaire Volbers, Jùn Zhou, Li Xie, R. Mohan Sankaran, and Daniel J. Lacks. "Electrostatic forces alter particle size distributions in atmospheric dust." Atmospheric Chemistry and Physics 20, no. 5 (March 17, 2020): 3181–90. http://dx.doi.org/10.5194/acp-20-3181-2020.

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Abstract. Large amounts of dust are lofted into the atmosphere from arid regions of the world before being transported up to thousands of kilometers. This atmospheric dust interacts with solar radiation and causes changes in the climate, with larger-sized particles having a heating effect, and smaller-sized particles having a cooling effect. Previous studies on the long-range transport of dust have found larger particles than expected, without a model to explain their transport. Here, we investigate the effect of electric fields on lofted airborne dust by blowing sand through a vertically oriented electric field, and characterizing the size distribution as a function of height. We also model this system, considering the gravitational, drag, and electrostatic forces on particles, to understand the effects of the electric field. Our results indicate that electric fields keep particles suspended at higher elevations and enrich the concentration of larger particles at higher elevations. We extend our model from the small-scale system to long-range atmospheric dust transport to develop insights into the effects of electric fields on size distributions of lofted dust in the atmosphere. We show that the presence of electric fields and the resulting electrostatic force on charged particles can help explain the transport of unexpectedly large particles and cause the size distribution to become more uniform as a function of elevation. Thus, our experimental and modeling results indicate that electrostatic forces may in some cases be relevant regarding the effect of atmospheric dust on the climate.
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Heavens, Nicholas G., David M. Kass, James H. Shirley, Sylvain Piqueux, and Bruce A. Cantor. "An Observational Overview of Dusty Deep Convection in Martian Dust Storms." Journal of the Atmospheric Sciences 76, no. 11 (October 16, 2019): 3299–326. http://dx.doi.org/10.1175/jas-d-19-0042.1.

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Abstract Deep convection, as used in meteorology, refers to the rapid ascent of air parcels in Earth’s troposphere driven by the buoyancy generated by phase change in water. Deep convection undergirds some of Earth’s most important and violent weather phenomena and is responsible for many aspects of the observed distribution of energy, momentum, and constituents (particularly water) in Earth’s atmosphere. Deep convection driven by buoyancy generated by the radiative heating of atmospheric dust may be similarly important in the atmosphere of Mars but lacks a systematic description. Here we propose a comprehensive framework for this phenomenon of dusty deep convection (DDC) that is supported by energetic calculations and observations of the vertical dust distribution and exemplary dusty deep convective structures within local, regional, and global dust storm activity. In this framework, DDC is distinct from a spectrum of weaker dusty convective activity because DDC originates from preexisting or concurrently forming mesoscale circulations that generate high surface dust fluxes, oppose large-scale horizontal advective–diffusive processes, and are thus able to maintain higher dust concentrations than typically simulated. DDC takes two distinctive forms. Mesoscale circulations that form near Mars’s highest volcanoes in dust storms of all scales can transport dust to the base of the upper atmosphere in as little as 2 h. In the second distinctive form, mesoscale circulations at low elevations within regional and global dust storm activity generate freely convecting streamers of dust that are sheared into the middle atmosphere over the diurnal cycle.
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Banks, Jamie R., Anja Hünerbein, Bernd Heinold, Helen E. Brindley, Hartwig Deneke, and Kerstin Schepanski. "The sensitivity of the colour of dust in MSG-SEVIRI Desert Dust infrared composite imagery to surface and atmospheric conditions." Atmospheric Chemistry and Physics 19, no. 10 (May 23, 2019): 6893–911. http://dx.doi.org/10.5194/acp-19-6893-2019.

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Abstract. Infrared “Desert Dust” composite imagery taken by the Spinning Enhanced Visible and InfraRed Imager (SEVIRI), onboard the Meteosat Second Generation (MSG) series of satellites above the equatorial East Atlantic, has been widely used for more than a decade to identify and track the presence of dust storms from and over the Sahara Desert, the Middle East, and southern Africa. Dust is characterised by distinctive pink colours in the Desert Dust false-colour imagery; however, the precise colour is influenced by numerous environmental properties, such as the surface thermal emissivity and skin temperature, the atmospheric water vapour content, the quantity and height of dust in the atmosphere, and the infrared optical properties of the dust itself. For this paper, simulations of SEVIRI infrared measurements and imagery have been performed using a modelling system, which combines dust concentrations simulated by the aerosol transport model COSMO-MUSCAT (COSMO: COnsortium for Small-scale MOdelling; MUSCAT: MUltiScale Chemistry Aerosol Transport Model) with radiative transfer simulations from the RTTOV (Radiative Transfer for TOVS) model. Investigating the sensitivity of the synthetic infrared imagery to the environmental properties over a 6-month summertime period from 2011 to 2013, it is confirmed that water vapour is a major control on the apparent colour of dust, obscuring its presence when the moisture content is high. Of the three SEVIRI channels used in the imagery (8.7, 10.8, and 12.0 µm), the channel at 10.8 µm has the highest atmospheric transmittance and is therefore the most sensitive to the surface skin temperature. A direct consequence of this sensitivity is that the background desert surface exhibits a strong diurnal cycle in colour, with light blue colours possible during the day and purple hues prevalent at night. In dusty scenes, the clearest pink colours arise from high-altitude dust in dry atmospheres. Elevated dust influences the dust colour primarily by reducing the contrast in atmospheric transmittance above the dust layer between the SEVIRI channels at 10.8 and 12.0 µm, thereby boosting red and pink colours in the imagery. Hence, the higher the dust altitude, the higher the threshold column moisture needed for dust to be obscured in the imagery: for a sample of dust simulated to have an aerosol optical depth (AOD) at 550 nm of 2–3 at an altitude of 3–4 km, the characteristic colour of the dust may only be impaired when the total column water vapour is particularly moist (⪆39 mm). Meanwhile, dust close to the surface (altitude <1 km) is only likely to be apparent when the atmosphere is particularly dry and when the surface is particularly hot, requiring column moisture ⪅13 mm and skin temperatures ⪆314 K, and is highly unlikely to be apparent when the skin temperature is ⪅300 K. Such low-altitude dust will regularly be almost invisible within the imagery, since it will usually be beneath much of the atmospheric water vapour column. It is clear that the interpretation of satellite-derived dust imagery is greatly aided by knowledge of the background environment.
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Takahashi, Y., M. Higashi, T. Furukawa, and S. Mitsunobu. "Change of iron species and iron solubility in Asian dust during the long-range transport from western China to Japan." Atmospheric Chemistry and Physics Discussions 11, no. 7 (July 8, 2011): 19545–80. http://dx.doi.org/10.5194/acpd-11-19545-2011.

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Abstract. In the North Pacific, transport and deposition of mineral dust from Asia appear to be one of major sources of iron which can regulate growth of phytoplankton in the ocean. In this process, it is essential to identify chemical species of iron contained in Asian dust, because bioavailability of iron in the ocean is strongly influenced by the solubility of iron, which in turn is dependent on iron species in the dust. Here, we report that clay minerals (illite and chlorite) in the dusts near the source (western China) are transformed into ferrihydrite by atmospheric chemical processes during their long-range transport to eastern China and Japan based on the speciation by X-ray absorption fine structure (XAFS) and other methods such as X-ray diffraction and chemical extraction. Moreover, it was found that iron in the dust after the transport becomes more soluble in our leaching experiments conducted for 24 h compared with those for initial dusts possibly due to the formation of ferrihydrite in the atmosphere. Our findings suggested that ferrihydrite secondarily formed during the transport is an important source of soluble iron species, which can be more soluble than clay minerals initially contained in the mineral dust such as illite and chlorite.
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Grogan, Dustin F. P., and Terrence R. Nathan. "Passive versus Active Transport of Saharan Dust Aerosols by African Easterly Waves." Atmosphere 12, no. 11 (November 16, 2021): 1509. http://dx.doi.org/10.3390/atmos12111509.

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Theory and modeling are combined to reveal the physical and dynamical processes that control Saharan dust transport by amplifying African easterly waves (AEWs). Two cases are examined: active transport, in which the dust is radiatively coupled to the circulation; passive transport, in which the dust is radiatively decoupled from the circulation. The theory is built around a dust conservation equation for dust-coupled AEWs in zonal-mean African easterly jets. The theory predicts that, for both the passive and active cases, the dust transports will be largest where the zonal-mean dust gradients are maximized on an AEW critical surface. Whether the dust transports are largest for the radiatively passive or radiatively active case depends on the growth rate of the AEWs, which is modulated by the dust heating. The theoretical predictions are confirmed via experiments carried out with the Weather Research and Forecasting model, which is coupled to a dust conservation equation. The experiments show that the meridional dust transports dominate in the passive case, while the vertical dust transports dominate in the active case.
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Liu, Z., D. Liu, J. Huang, M. Vaughan, I. Uno, N. Sugimoto, C. Kittaka, et al. "Airborne dust distributions over the Tibetan Plateau and surrounding areas derived from the first year of CALIPSO lidar observations." Atmospheric Chemistry and Physics 8, no. 16 (August 29, 2008): 5045–60. http://dx.doi.org/10.5194/acp-8-5045-2008.

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Abstract. Using an analysis of the first full year of CALIPSO lidar measurements, this paper derives unprecedented, altitude-resolved seasonal distributions of desert dust transported over the Tibetan Plateau (TP) and the surrounding areas. The CALIPSO lidar observations include numerous large dust plumes over the northern slope and eastern part of the TP, with the largest number of dust events occurring in the spring of 2007, and some layers being lofted to altitudes of 11–12 km. Generation of the Tibetan airborne dusts appears to be largely associated with source regions to the north and on the eastern part of the plateau. Examination of the CALIPSO time history reveals an "airborne dust corridor" due to the eastward transport of dusts originating primarily in these source areas. This corridor extends from west to east and shows a seasonality largely modulated by the TP through its dynamical and thermal forcing on the atmospheric flows. On the southern side, desert dust particles originate predominately in Northwest India and Pakistan. The dust transport occurs primarily in dry seasons around the TP western and southern slopes and dust particles become mixed with local polluted aerosols. No significant amount of dust appears to be transported over the Himalayas. Extensive forward trajectory simulations are also conducted to confirm the dust transport pattern from the nearby sources observed by the CALIPSO lidar. Comparisons with the OMI and MODIS measurements show the unique capability of the CALIPSO lidar to provide unambiguous, altitude-resolved dust measurements.
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Schepanski, Kerstin, Bernd Heinold, and Ina Tegen. "Harmattan, Saharan heat low, and West African monsoon circulation: modulations on the Saharan dust outflow towards the North Atlantic." Atmospheric Chemistry and Physics 17, no. 17 (September 1, 2017): 10223–43. http://dx.doi.org/10.5194/acp-17-10223-2017.

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Abstract. The outflow of dust from the northern African continent towards the North Atlantic is stimulated by the atmospheric circulation over North Africa, which modulates the spatio-temporal distribution of dust source activation and consequently the entrainment of mineral dust into the boundary layer, as well as the transport of dust out of the source regions. The atmospheric circulation over the North African dust source regions, predominantly the Sahara and the Sahel, is characterized by three major circulation regimes: (1) the harmattan (trade winds), (2) the Saharan heat low (SHL), and (3) the West African monsoon circulation. The strength of the individual regimes controls the Saharan dust outflow by affecting the spatio-temporal distribution of dust emission, transport pathways, and deposition fluxes.This study aims at investigating the atmospheric circulation pattern over North Africa with regard to its role favouring dust emission and dust export towards the tropical North Atlantic. The focus of the study is on summer 2013 (June to August), during which the SALTRACE (Saharan Aerosol Long-range TRansport and Aerosol-Cloud interaction Experiment) field campaign also took place. It involves satellite observations by the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) flying on board the geostationary Meteosat Second Generation (MSG) satellite, which are analysed and used to infer a data set of active dust sources. The spatio-temporal distribution of dust source activation frequencies (DSAFs) allows for linking the diurnal cycle of dust source activations to dominant meteorological controls on dust emission. In summer, Saharan dust source activations clearly differ from dust source activations over the Sahel regarding the time of day when dust emission begins. The Sahara is dominated by morning dust source activations predominantly driven by the breakdown of the nocturnal low-level jet. In contrast, dust source activations in the Sahel are predominantly activated during the second half of the day, when downdrafts associated with deep moist convection are the major atmospheric driver. Complementary to the satellite-based analysis on dust source activations and implications from their diurnal cycle, simulations on atmosphere and dust life cycle were performed using the mesoscale atmosphere–dust model system COSMO-MUSCAT (COSMO: COnsortium for Small-scale MOdelling; MUSCAT: MUltiScale Chemistry Aerosol Transport Model). Fields from this simulation were analysed regarding the variability of the harmattan, the Saharan heat low, and the monsoon circulation as well as their impact on the variability of the Saharan dust outflow towards the North Atlantic. This study illustrates the complexity of the interaction among the three major circulation regimes and their modulation of the North African dust outflow. Enhanced westward dust fluxes frequently appear following a phase characterized by a deep SHL. Ultimately, findings from this study contribute to the quantification of the interannual variability of the atmospheric dust burden.
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Osada, K., S. Ura, M. Kagawa, M. Mikami, T. Y. Tanaka, S. Matoba, K. Aoki, et al. "Wet and dry deposition of mineral dust particles in Japan: factors related to temporal variation and spatial distribution." Atmospheric Chemistry and Physics 14, no. 2 (January 29, 2014): 1107–21. http://dx.doi.org/10.5194/acp-14-1107-2014.

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Abstract. Recent ground networks and satellite remote-sensing observations have provided useful data related to spatial and vertical distributions of mineral dust particles in the atmosphere. However, measurements of temporal variations and spatial distributions of mineral dust deposition fluxes are limited in terms of their duration, location, and processes of deposition. To ascertain temporal variations and spatial distributions of mineral dust deposition using wet and dry processes, weekly deposition samples were obtained at Sapporo, Toyama, Nagoya, Tottori, Fukuoka, and Cape Hedo (Okinawa) in Japan during October 2008–December 2010 using automatic wet and dry separating samplers. Mineral dust weights in water-insoluble residue were estimated from Fe contents measured using an X-ray fluorescence analyser. Wet and dry deposition fluxes of mineral dusts were both high in spring and low in summer, showing similar seasonal variations to frequency of aeolian dust events (Kosa) in Japan. For wet deposition, highest and lowest annual dust fluxes were found at Toyama (9.6 g m−2 yr−1) and at Cape Hedo (1.7 g m−2 yr−1) as average values in 2009 and 2010. Higher wet deposition fluxes were observed at Toyama and Tottori, where frequent precipitation (> 60% days per month) was observed during dusty seasons. For dry deposition among Toyama, Tottori, Fukuoka, and Cape Hedo, the highest and lowest annual dust fluxes were found respectively at Fukuoka (5.2 g m−2 yr−1) and at Cape Hedo (2.0 g m−2 yr−1) as average values in 2009 and 2010. The average ratio of wet and dry deposition fluxes was the highest at Toyama (3.3) and the lowest at Hedo (0.82), showing a larger contribution of the dry process at western sites, probably because of the distance from desert source regions and because of the effectiveness of the wet process in the dusty season. Size distributions of refractory dust particles were obtained using four-stage filtration: > 20, > 10, > 5, and > 1 μm diameter. Weight fractions of the sum of > 20 μm and 10–20 μm (giant fraction) were higher than 50% for most of the event samples. Irrespective of the deposition type, the giant dust fractions generally decreased with increasing distance from the source area, suggesting the selective depletion of larger giant particles during atmospheric transport. Based on temporal variations of PMc (2.5 < D < 10 μm), ground-based lidar, backward air trajectories, and vertical profiles of potential temperatures, transport processes of dust particles are discussed for events with high-deposition and low-deposition flux with high PMc. Low dry dust depositions with high PMc concentrations were observed under stronger (5 K km−1) stratification of potential temperature with thinner and lower (< 2 km) dust distributions because the PMc fraction of dust particles only survived after depletion of giant dust particles by rapid gravitational settling at the time they reach Japan. In contrast, transport through a thicker (> 2 km) dust layer with weak vertical gradient of potential temperature carry more giant dust particles to Japan. Because giant dust particles are an important mass fraction of dust accumulation, especially in the North Pacific, which is known as a high-nutrient, low-chlorophyll (HNLC) region, the transport height and fraction of giant dust particles are important factors for studying dust budgets in the atmosphere and their role in biogeochemical cycles.
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Voss, Kara K., Amato T. Evan, Kimbery A. Prather, and F. Martin Ralph. "Dusty Atmospheric Rivers: Characteristics and Origins." Journal of Climate 33, no. 22 (November 15, 2020): 9749–62. http://dx.doi.org/10.1175/jcli-d-20-0059.1.

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AbstractAtmospheric rivers (AR) are narrow bands of strong horizontal transport of water vapor in the midlatitudes that can cause extreme precipitation, which contributes to beneficial water supply and sometimes flooding. The precipitation productivity of an AR is affected by microphysical processes, including the influence of aerosols. Earlier case studies have shown that some ARs over the North Pacific Ocean contain dust from Africa and Asia that can strongly influence precipitation by acting as ice nuclei. This paper explores how commonly dust and ARs occur together, or in close proximity. A “dust score” is introduced to characterize the dustiness of the environment associated with ARs by using satellite-based observations. This method is applied to days on which one or more ARs made landfall along the west coast of the United States between 2001 and 2018. The dust score is used to describe the seasonality and year-to-year variability of dusty-environment ARs. Dusty ARs occur primarily in the early spring (March–April), and dust is preferentially found within the warm sector of AR-associated extratropical cyclones and is also enhanced in the cold sector. Year-to-year variability in dust score is dependent more on year-to-year variability in dust than on the frequency of AR days. This year-to-year variability is also strongly related to correlations between the frequency of ARs and the dustiness of the northeastern Pacific, motivating additional investigation into potential dynamical association between dust and ARs.
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Dissertations / Theses on the topic "Atmospheric dust transport"

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Mulholland, David Paul. "Martian dust lifting, transport and associated processes." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:a94d810a-5c55-4b7e-84b4-04d4f3b4f191.

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The dust lifting capacity of the UK Mars General Circulation Model has been extended through the development of a new wind stress lifting parameterisation, and the simulation of a finite, variable surface dust layer. This second addition, which was represented by the use of lifting thresholds that were adjusted at each surface gridpoint in response to the removal or deposition of dust, led to enhanced variability in the timing and peak magnitude of major dust storms produced in the model. These dust storms were realistic in many respects, and the observed global dust storm frequency of occurrence of roughly one in every three years was approximately reproduced by the model, but an artificial threshold decrease rate was required to maintain dust lifting on a multiannual timescale - this was believed to be due to inaccuracies in the net cross-equatorial dust flux, which showed a strong bias towards the northern hemisphere. Significant changes were seen in model dust lifting rates when the influence of a heterogeneous surface roughness length was included in the wind stress scheme, and the need for more sophisticated sub-gridscale methods in future dust lifting schemes, to cope with this and other effects, was noted. The inclusion of radiatively active water clouds in model runs also affected dust lifting rates, particularly in the vicinity of the polar caps in autumn, winter and spring. The dynamics behind the formation of small, cap-edge dust storms during these periods were examined in detail, and it was found that a cessation in dust lifting activity that occurs around winter solstice does so due to a combination of the radiative effects of global dust loading and polar hood ice clouds, and zonal variations in midlatitude topography. The direct interaction between dust and ice, in the form of nucleation and scavenging, was investigated. It was found that scavenging by water ice, if it is suitably efficient, could significantly reduce the dust content of the winter polar regions. However, the dust and ice vertical profiles measured in the aphelion cloud belt by Mars Climate Sounder were not reproduced by the model with any of the possible scavenging efficiencies used. It appears that scavenging cannot provide an explanation for the existence of sharply defined, elevated dust layers at low latitudes.
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Engelstaedter, Sebastian. "An analysis of the role of the atmosphere in modulating desert dust variability : controls on emission and atmospheric transport." Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443725.

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Wei, Chao. "Modeling the effects of heterogeneous reactions on atmospheric chemistry and aerosol properties." Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/903.

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In this thesis, a new aerosol module is developed for the STEM model (the Sulfur Transport and dEposition Model) to better understand the chemical aging of dust during long range transport and assess the impact of heterogeneous reactions on tropospheric chemistry. The new aerosol module is verified and first applied in a box model, and then coupled into the 3-Dimentional STEM model. In the new aerosol model, a non-equilibrium (dynamic or kinetic) approach to treat gas-to-particular conversion is employed to replace the equilibrium method in STEM model. Meanwhile, a new numerical method solving the aerosol dynamics equation is introduced into the dynamic aerosol model for its improved computational efficiency and high accuracy. Compared with the equilibrium method, the new dynamic approach is found to provide better results on predicating the different hygroscopicity and chemical aging patterns as a function of size. The current modeling study also takes advantage of new findings from laboratory experiments about heterogeneous reactions on mineral oxides and dust particles, in order to consider the complexity of surface chemistry (such as surface saturation, coating and relative humidity). Modeling results show that the impacts of mineralogy and relative humidity on heterogeneous reactions are significant and should be considered in atmospheric chemistry modeling with first priority. Finally, the upgraded 3-D STEM model is utilized to explore the observations from the Intercontinental Chemical Transport Experiment - Phase B (INTEX-B). The new dynamic approach for gas-to-particular conversion and RH-dependent heterogeneous uptake of HNO3 improve the model performance in term of aerosol predictions under different conditions. It is shown that these improvements change the modeled nitrate and sulfate concentrations, but also modify their size distributions significantly.
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Newton, Seth. "Occurrence and fate of emerging and legacy flame retardants : from indoor environments to remote areas." Doctoral thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-116443.

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Persistent organic pollutants (POPs) are toxic chemicals that can be found in various matrices in all corners of the planet, including remote areas such as the Arctic.  Several POPs are known and monitored but given the abundance of new chemicals in commerce about which little is known, chemicals that may be new POPs are constantly being screened for. The use of flame retardants, particularly brominated flame retardants (BFRs), has been increasing for decades. PBDEs and HBCDDs are two types of BFRs that have historically been used in large volumes but recently faced legislative restrictions. However, in order to meet fire safety standards, these BFRs have been replaced by a variety of emerging flame retardants (EFRs) about which little is known especially concerning their toxicity, production volumes, and environmental behavior. The main purpose of this thesis was to investigate the occurrence and fate in indoor and outdoor environments of several EFRs and compare them with PBDEs, HBCDDs, and legacy POPs. Several indoor environments in the city of Stockholm, Sweden were sampled for dust, indoor air, and ventilation system air (Paper II).  Results from these samples revealed a number of EFRs that humans are exposed to and that are emitted from buildings through ventilation systems. These included DDC-CO, DBE-DBCH, PBT, HBB, EHTBB, and BEH-TEBP. PBDE levels seem to be declining compared to previous studies in Stockholm.  Outdoor air and soil were sampled across transects of Stockholm (Paper II) and Birmingham, United Kingdom (Paper III).  Results from these samples showed the presence of many of the same EFRs in the outdoor environment that were found in indoor environments.  Urban pulses in air were discovered for PBDEs in both cities and for some EFRs in Stockholm, indicating that the cities are sources of EFRs to the outdoor environment.  Atmospheric deposition samples were taken at two sites in northern Sweden (Paper I).  Three EFRs (DDC-CO, DBE-DBCH, and BTBPE) and two current-use pesticides (trifluralin and chlorothalonil) were identified, indicating these compounds’ potential for long range transport and global contamination.  Other legacy POPs such as HCH, PCBs, and PBDEs were measured in the deposition samples as well.  The bulk of deposition was comprised of HCH and PCBs with only minor contributions from PBDEs, chlordanes, and emerging compounds.  Finally, passive and active air sampling methods were compared for BFRs in offices in Beijing, China.  Some EFRs were identified in indoor air from China; however, BDE-209 was the most predominant compound found (Paper IV).  Air samples collected with passive samplers generally had measured FR concentrations within a factor of 2-3 of those collected with active samplers. The use of a GFF in the passive samplers resulted in concentrations of particle-bound contaminants such as BDE-209 that were more comparable to those in active samples. The positioning of the PUF in the passive samplers affected the sampling rates for gaseous compounds and particle retention on PUFs was shown to be a large source of uncertainty in passive sampling.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.

 

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Silva, Marcio Cataldo Gomes da. "Características biogeoquímicas da interação atmosfera criosfera na Antártica ocidental." Universidade do Estado do Rio de Janeiro, 2011. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=3339.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
O manto polar antártico retêm informação paleoclimatologica por entres suas camadas de neve e gelo. O gelo antártico tem revelado a base de dados paleoclimática de maior resolução para os últimos 800 mil anos. Os padrões de transporte atmosférico refletem a composição e a fonte do particulado encontrado na neve e no gelo do continente Antártico. Estando relacionado a processos climáticos, as características desse transporte alteram em quantidade e qualidade as espécies químicas que se depositam sobre o manto de gelo. Dessa forma, o estudo dos depósitos de particulado ao longo das camadas de neve/gelo na Antártica pode sugerir mudanças nos padrões de transporte atmosférico. Atualmente a comunidade científica discute as diferenças de padrões climáticos entre o leste e o oeste antártico. Enquanto de forma geral observa-se instabilidade no setor oeste, o clima da antártica oriental demonstra relativa estabilidade climática. Neste estudo, analisamos dois testemunhos de gelo recente de duas regiões com características climáticas diferentes do continente Antártico. No Platô Detroit situado na Península Antártica (6410′S/0600′O), analisamos a variabilidade de Black Carbon (BC) ao longo de 20 metros de neve. O BC encontrado na Península Antártica apresentou baixas concentrações comparáveis as encontradas no gelo do Artico período pré-industrial. Nossos resultados sugerem que sua variabiliade corresponde à sazonalidade dos períodos de queimada nos continentes do Hemisfério Sul. No interior do continente Antártico, analisamos o particulado em geral por um processo de microanálise ao longo de um testemunho de 40 metros extraído em Mont Johns (79o55′S/09423′O). Encontramos uma tendência negativa na deposição de poeira mineral (AlSi) entre 1967 e 2007. Nossos resultados sugerem que esta tendência seja resultado de um crescente isolamento atmosférico da região central do continente antártico pelo aumento da intensidade dos ventos ao redor da Antártica. Este aumento na intensidade dos ventos reflete por sua vez o resfriamento da alta atmosfera no centro antártico causado pela depleção da camada de ozônio na região. Adicionalmente, amostras de diferentes microambientes de Patriot Hills (8018′S/08121′O) foram coletadas de maneira asséptica para análise microbiológica. As amostras foram cultivadas em meio R2 e paralelamente o DNA total extraído foi sequenciado pela técnica de pirosequenciamento. Os resultados preliminares desta analise mostram grande riqueza de espécies dos mais variados grupos. Os resultados deste trabalho caracterizam três diferentes parâmetros relacionados a deposição atmosférica em duas áreas pouco exploradas e de grande interesse científico do continente antártico.
The antarctic ice cap stores paleoclimatological information within layers of snow and ice. Antarctic ice has revealed the higher resolution paleoclimactic database for the last 800 kyr. Atmospheric transport plays a fundamental role on the composition and sources of particulate matter found in the Antarctic ice. It has been related to several climatic processes that changes the quantity and quality of exogenous aerosols reaching Antarctica. Therefore, studies of the particulate matter deposits along the snow/ice layers may suggest changes on atmospheric transport patterns. This work, analyze two recent ice cores from two climatic distinct regions of the Antarctic continent. One retrieved from Detroit Plateau/Antarctic Peninsula (6410′S/0600′W), in which we have analyze Black Carbon (BC) deposition and variability along 20 meters of snow. BC found in the Antarctic Peninsula showed low concentrations (varing between 0,014 and 3,733ppb), comparable to the concentrations found on Arctic ice dated from before the industrial revolution period. Our results suggest that peaks of BC detected correspond, mostly, to biomass burning seasons in the South Hemisphere, not speficically from South America. The second one, of 40 m, was retrieved from Central-West Antarctica, Mont Johns (79o55′S/094 23′W), in which we analyzed the mineral dust abundance thought M.E.V. E.D.X. technique. In this study we found negative trends in mineral dust (inferred from Fe, Ti and AlSi) deposition between 1967 and 2007, in contrast to similar works in Sub-antarctic regions. We demonstrate that this trend is a consequence of the persistent atmospheric isolation that encloses the Central and East Antarctic regions due to the increasing winds around Antarctica within this period. It has been documented that westerlies intensification reflect the upper atmosphere cooling above Central Antarctica caused by the stratospherical ozone layer depletion. As part of the polar site characterization, we additionally have performed sampling for microbiological purpose from distinct microenvironments at Patriot Hills (8018′S/08121′W). Samples were cultivated on R2 media and at the same time total DNA on samples was extracted and sent to a pyrosequencing analysis. Preliminary results show richness and diversity of bacterial species distributed on five phyla.
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Qu, Zihan. "Chemical properties of continental aerosol transported over the Southern Ocean : Patagonian and Namibian sources." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066002/document.

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Patagonie et la Namibie sont deux sources importantes d'aérosol minéral qui alimente la section Atlantique Sud de l'océan Austral avec les micronutriments.L'objet de ma thèse est d'étudier 1) la concentration atmosphérique et la variation temporel de la poussière en Patagonie, 2) l'hétérogénéité spatiale de composition élémentaire de poussière en Patagonie et en Namibie, et 3) la solubilité élémentaire de poussière en Patagonie et en Namibie. Ces trois aspects sont les principaux enjeux pour modéliser les inventaires des émissions de micronutriments biodisponibles à partir de sources de poussière.La concentration en poussière mesurée en Patagonie montre une variation saisonnière avec un niveau plus bas en hiver. Les données météorologiques suggèrent que cette variation saisonnière est associée à la variation de l'humidité du sol dans les zones source plutôt qu'à la vitesse du vent. Des échantillons d'aérosol minéral ont été générés à partir des sols de Patagonie et de Namibie. La composition élémentaire des poussières diffère de celles des sols parents, en particulier en Namibie en raison de l'effet de dilution par le quartz dans les sols. Des compositions élémentaires varient spatialement aux échelles continentale et régionale en Patagonie et Namibie. Les variations de Ca et Mg sont les principales raisons conduisant à l'hétérogénéité spatiale de la composition élémentaire des poussières. Les solubilités élémentaires des aérosols minéraux de Patagonie et de Namibie augmentent avec l'acidité de la solution altérante. Les poussières riches en calcium présentent une solubilité plus élevée pour les éléments les plus solubles (Ca, etc.) en raison de la présence de carbonate. Le suivi de la concentration en poussières obtenu en Patagonie peut aider à mieux en quantifier les émissions dans la région subantarctique et ainsi à mieux contraindre les modèles. La base de données que nous avons obtenue sur les poussières et leur solubilité contribue également à l'évaluation des émissions d'éléments solubles dans la région Australe
Mineral dust is considered to be an important supplier of micronutrient for the Southern Ocean where the primary production is limited by insufficient supply of micronutrients. Patagonia (South America) and Namibia (Southern Africa) are two main dust sources for the South Atlantic section of the Southern Ocean. Emission inventories of bioavailable micronutrients from these two regions regulate the final biological impact on marine ecosystem in the South Atlantic Ocean. This thesis is mainly focused on the investigation of 1) the atmospheric dust concentration and its temporal pattern in Patagonia, 2) the spatial heterogeneity of dust elemental composition in Patagonia and Namibia, and 3) the pH dependence of elemental solubility in Patagonian and Namibian dust. These three aspects are the key issues to model the emission inventories of bioavailable micronutrients from dust sources. Dust concentration measurements were conducted in Patagonia-Atlantic Coast and revealed a seasonal pattern of dust concentration with lower dust level in winter than the other three seasons. Meteorological records suggest that this seasonal pattern is associated with the variation of soil moisture in source areas rather than the recurrently high wind speed. Dust samples were generated from Patagonian and Namibian soils to investigate the elemental composition and the elemental solubility of source dust. Dust elemental composition differs to different degrees from their parents soils, particularly in Namibia due to the dilution effect of quartz in soil. Spatial variability of dust elemental composition was observed at both continental scale and regional scale in Patagonia and Namibia. Variations in Ca and Mg content are the main reasons for the spatial heterogeneity of dust elemental composition. Elemental solubility of Patagonian and Namibian dust increased with acidity of leaching solution. More soluble elements namely Ca, K, Mg, Mn, Sr and Ba showed much higher solubility in calcium-rich dust due to the presence of carbonate. The dust concentration record obtained in Patagonia may help to better quantify the dust emission in subantarctic region and to constrain dust models. Database of dust elemental composition and elemental solubility in Patagonia and Namibia also contributes to the evaluation of emission inventories of soluble elements from dust sources to the Southern Ocean
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Haga, Donna. "Ice nucleation by mineral dusts, fungal spores, and bacteria : implications for climate and the long-distance transport of these aerosols in the atmosphere." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45241.

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In the atmosphere, ice can form on solid aerosol particles called ice nuclei. This research focuses on the ice nucleation properties of mineral dusts and biological particles. The motivation for this research is two-fold. First, ice nucleation on these aerosols may influence cloud formation, cloud reflectivity and precipitation patterns in what is an indirect climate effect. This effect is one of the largest uncertainties in current climate models. Second, ice nucleation may be an important removal mechanism for these particles from the atmosphere and may influence their long-distance transport. Currently, ice nucleation is represented in a simplistic manner or not at all in models used to predict the long-distance transport of aerosols. A temperature and humidity controlled flow cell coupled to an optical microscope was used to study the ice nucleation properties of four mineral dusts, eighteen fungal spores, and six bacteria. It was found that acidic coatings reduce the ice nucleating ability of the mineral dusts. The fungal spores showed a wide range of ice nucleating properties and there was no inherent difference in the ice nucleation ability of spores belonging to different taxonomic groups. Four of the bacteria studied were very poor ice nuclei and the fifth bacterium was an excellent ice nucleus. The results from the flow cell experiments on fungal spores were used to describe ice nucleation in two modeling studies that simulated atmospheric transport. One study found that a significant fraction of large fungal spores (20 micrometers in diameter) can reach high altitudes where they could act as ice nuclei. The other study focused on smaller spores (3 to 8 micrometers) and found that ice nucleation on these spores effects their long-distance transport to polar and marine regions. The laboratory results were used to show that mineral dusts are more important than the fungal spores or bacteria that were studied on a global annual scale. These results can be used to improve parameterizations of ice nucleation on mineral dusts and biological particles in future modeling studies investigating the indirect effect of aerosols on climate or the long-distance transport of aerosols in the atmosphere.
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Huei, Chang Ming, and 張銘惠. "Atmospheric Particulate PAH Patterns of China Long-Range Transport Dust Storms and Taiwan Local Festival Celebration Events." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/b7hgvu.

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碩士
輔仁大學
公共衛生學系碩士班
97
PAHs, by products of incomplete combustion or pyrolysis of hydrocarbons, can be regarded as important representative chemicals on long-range transportation particles. Moreover, the concentrations and patterns of particle-bound PAHs in the atmosphere are used as indicators of regional air quality to assess the exposure risk to human health. In recent years, many PAHs sources, such as vehicle exhaust, stack gas etc. have contributed to the PAHs levels in the Taiwan atmosphere. In addition to local sources, the notable events include dust storm particles from China, firework and barbecue smoke in Taiwan local festival events. This study discussed the characteristic ratios (CR) of PAHs and distinguished possible PAHs sources in various scenarios. This study collected airborne PAHs samples on the Fu Jen University campus from 2007 to 2008. A Micro-Orifice Uniform Deposit Impactor (MOUDI ) instrument was used to collected particle size segregated samples in the dust storm events in 2002-2008. This study also used filters and gas adsorbent (F/A) samplers to collect particulate matters and gaseous PAHs in Ghost Festival and Moon Festival in 2007-2008. The final portion of this study was to examine the pollution extent of smoke particles in the firework event at Tainan Yanshuai in 2009. The 34 PAHs results showed that air samples taken from different heights (altitude of 10 meters and 20 meters from the sea level) showed no statistically significant difference with respect to particulate mass concentration and 34 PAH concentrations. These results were pooled and regarded as the PAHs background level in Taipei. Similar PAHs patterns were found in Tainan background with lower concentrations. The major gas-phase PAHs included Naph, 2mN, 1mN and BP, whereas the main solid-phase PAHs were BbF, BghiP, IcdP. The average atmospheric particle-PAHs concentration in 2007 Ghost Festival was 9.08 ng/m3, which was much higher than the background level (2.35 ± 1.99 ng/m3). One possible explanation is that significant amounts of resemble money for the dead was burned during the Ghost festival. Mass concentrations of total suspended particulate (TSP) in the Tainan Yanshuai firework are 265.1 ~ 844.8 μg/m3, far above the EPA air quality standards (250 μg/m3). Additionally, fireworks used during the Yanshuai festival caused atmospheric PAHs concentrations rising to 42.0 ~ 71.1 ng/m3 which was 10 times higher than the background condition. At the same time, the concentration of BaP in the firework event also increased significantly, 0.06~0.46 ng/m3, implying the potential health hazards. By using the characteristic ratios (CR) related to BbF, this study also found that the dust storm events attributed significant particle-bound PAHs to Taiwan. The CRs of BkF and BaP were found to be significantly higher than the background CRs as dust particles were transported through North China, originally from Mongolia. At the mixing layer below 1000 m, the dust storm particles are likely mixed with regional airborne pollutants, such as PAHs, then migrated to the down wind locations. This study suggested that the comparison of particle-bound PAH CRs along the NOAA backward trajectory routes to Taiwan could provide more information in describing PAH partitioning phenomena during the dust particle transportation. The significant contribution of TSP mass and PAHs concentrations are followed by the orders of Yanshuai fireworks, dust storm, Ghost Festival and Moon Festival. The applications of PAH CR values can be used to distinguished particle-bound origins from the local pollution sources in the dust storm long range transportion. However, more regional PAHs patterns in the dust storm pathways were needed to evaluate the possible aerosol-pollutant interaction mechanism during the transportation.
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Santee, Michelle. "The thermal structure, dust loading, and meridional transport in the Martian atmosphere during late southern summer." Thesis, 1993. https://thesis.library.caltech.edu/7384/1/Santee_m_1993.pdf.

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This thesis consists of two papers, both of which investigate the state of the Martian atmosphere during a relatively clear period in late southern summer. The first paper describes a new technique for the simultaneous retrieval of atmospheric temperatures and dust abundances from thermal emission spectra. The second paper describes a diagnostic stream function model which is used with the temperature and dust results of the first paper to solve for the meridional and vertical components of the diabatic circulation simultaneously. The abstracts for the two papers are reproduced below.

PAPER I:

The temperature structure and dust loading of the Martian atmosphere are investigated using thermal emission spectra recorded by the Mariner 9 infrared interferometer spectrometer (IRIS). The analysis is restricted to a subset of the IRIS data consisting of approximately 2400 spectra in a 12-day period extending from L_s = 343° to L_s = 348°, corresponding to late southern summer on Mars. Simultaneous retrieval of the vertical distribution of both atmospheric temperature and dust optical depth is accomplished through an iterative procedure which is performed on each spectrum. The inclusion of dust opacity in the retrieval algorithm causes the retrieved temperatures to change by more than 20 K in some atmospheric layers. The largest column-integrated 9 µm dust optical depths (~ 0.4) occur over the equatorial regions. The highest atmospheric temperatures (> 260 K) are found at low altitudes near the sub-solar latitude (~ 6° s), while the coldest temperatures (˂ 150 K) are found at levels near 1.0 mbar over the winter pole. A comparison of temperature maps for 2 PM and 2 AM indicates diurnal temperature variations as large as 80 K at low altitudes near the sub- solar latitude, whereas diurnal temperature changes at pressures less than 1.0 mbar are typically about 10 K. Both dayside and nightside temperatures above about 0.1 mbar (~ 40 km) are warmer over the winter (north) polar region than over the equator or the summer (south) polar region. This thermal structure suggests the existence of a net zonally-averaged meridional circulation with rising motion at low latitudes, poleward flow at altitudes above 40 km, and subsidence over the poles. Because a meridional circulation transports atmospheric constituents as well as heat, it has significant implications for the net flux of dust and water into the polar regions.

PAPER II:

The circulation of the Martian atmosphere during late southern summer is calculated diagnostically from the observed atmospheric temperature distribution. We use global maps of temperature and dust optical depth (~ 0-60 km) retrieved from a subset of the Mariner 9 IRIS thermal emission spectra spanning L_s = 343°- 348° [Santee and Crisp, 1992]. This thermal structure is characterized by a reversed meridional temperature gradient (temperatures increasing poleward) at altitudes above about 40 km. Zonal- mean zonal winds are derived from the zonally-averaged temperatures assuming gradient wind balance and zero surface zonal wind. Both hemispheres have intense mid- latitude westerly jets (with velocities of 80- 90 m/s near 50 km); in the southern tropics the winds are strongly easterly (with velocities of 100 m/s near 50 km). The north-south atmospheric transport includes contributions from the zonal- mean meridional circulation and large-scale waves. Their net effect can be approximated by the diabatic circulation, which is that circulation needed to maintain the observed temperature distribution (warm winter pole, cool tropics) in the presence of the radiative forcing. A radiative transfer model [Crisp, 1990] which accounts for absorption, emission and multiple scattering by particles and non- grey gases is used to compute the solar heating and thermal cooling rates from diurnal averages of the retrieved IRlS temperature and dust distributions. At pressures below 4 mbar, there are large net heating rates (up to 8 K/ day) in the equatorial region and large net cooling rates (up to 20 K/ day) in the polar regions. These net heating rates are used in a diagnostic stream function model which solves for the meridional and vertical components of the diabatic circulation simultaneously. We find a two-cell circulation, with upwelling over the equator(~ 1.5 cm/s), poleward motion in both hemispheres(~ 2 m/s), and subsidence over the poles (1-2 cm/ s). This circulation is sufficiently vigorous that the meridional transport time scale is ~ 13 days. Vertical transport is primarily advective in nature, except in the high-altitude winter polar regions, where diffusive processes dominate. Water vapor desorbed from the low-latitude regolith during late northern winter/ early northern spring may be transported upward by the ascending branch of this circulation, where it would be transported poleward by the high-altitude meridional winds. This process could provide a high-altitude source of water vapor for the polar hood.

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Books on the topic "Atmospheric dust transport"

1

1946-, Leinen Margaret, Sarnthein M, and North Atlantic Treaty Organization, eds. Paleoclimatology and paleometeorology: Modern and past patterns of global atmospheric transport. Dordrecht: Kluwer Academic Publishers, 1989.

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Leinen, Margaret, and Michael Sarnthein. Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport. Springer, 2012.

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Leinen, Margaret, and Michael Sarnthein. Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport. Springer, 2012.

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(Editor), Margaret Leinen, and Michael Sarnthein (Editor), eds. Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport (NATO Science Series C: (closed)). Springer, 2007.

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Lau, William K. M. Impacts of Aerosols on Climate and Weather in the Hindu-Kush-Himalayas-Gangetic Region. Oxford University Press, 2018. http://dx.doi.org/10.1093/acrefore/9780190228620.013.590.

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Situated at the southern edge of the Tibetan Plateau (TP), the Hindu-Kush-Himalayas-Gangetic (HKHG) region is under the clear and present danger of climate change. Flash-flood, landslide, and debris flow caused by extreme precipitation, as well as rapidly melting glaciers, threaten the water resources and livelihood of more than 1.2 billion people living in the region. Rapid industrialization and increased populations in recent decades have resulted in severe atmospheric and environmental pollution in the region. Because of its unique topography and dense population, the HKHG is not only a major source of pollution aerosol emissions, but also a major receptor of large quantities of natural dust aerosols transported from the deserts of West Asia and the Middle East during the premonsoon and early monsoon season (April–June). The dust aerosols, combined with local emissions of light-absorbing aerosols, that is, black carbon (BC), organic carbon (OC), and mineral dust, can (a) provide additional powerful heating to the atmosphere and (b) allow more sunlight to penetrate the snow layer by darkening the snow surface. Both effects will lead to accelerated melting of snowpack and glaciers in the HKHG region, amplifying the greenhouse warming effect. In addition, these light-absorbing aerosols can interact with monsoon winds and precipitation, affecting extreme precipitation events in the HKHG, as well as weather variability and climate change over the TP and the greater Asian monsoon region.
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Vaughan, David. 4. Earth’s surface and the cycling of minerals. Oxford University Press, 2014. http://dx.doi.org/10.1093/actrade/9780199682843.003.0004.

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‘Earth’s surface and the cycling of minerals’ considers the rock cycle, which has two parts. The first is driven by the heat coming from the Earth’s interior and involves interactions between the mantle and crust. The second is driven primarily by heat from the Sun and involves interactions between exposed crust and the waters of the hydrosphere or gases of the atmosphere. Minerals in these exposed rocks may be dissolved during weathering, or be transported in the flowing water of streams and rivers, by glaciers, or as fine mineral dusts in the atmosphere, eventually being deposited elsewhere as sediments. The rock cycle also impacts on pollution and global warming.
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Dagsson-Waldhauserova, Pavla, and Outi Meinander, eds. Atmosphere – Cryosphere Interaction in the Arctic, at High Latitudes and Mountains with Focus on Transport, Deposition and Effects of Dust, Black Carbon, and other Aerosols. Frontiers Media SA, 2020. http://dx.doi.org/10.3389/978-2-88963-504-7.

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Book chapters on the topic "Atmospheric dust transport"

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Merrill, J., R. Arimoto, G. Bergametti, S. Joussaume, S. Thompson, and D. Westphal. "Dust Transport and Transport Modeling." In Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, 865–68. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0995-3_37.

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Tetzlaff, G., M. Peters, W. Janssen, and L. J. Adams. "Aeolian Dust Transport in West Africa." In Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, 185–203. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0995-3_7.

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Schuetz, Lothar. "Atmospheric Mineral Dust - Properties and Source Markers." In Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, 359–83. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0995-3_15.

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Nickling, W., A. Brazel, D. Gillette, N. J. Middleton, K. Pye, P. Rognon, and G. Tetzlaff. "Dust Formation, Injection, and Continental Aridity." In Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, 861–63. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0995-3_36.

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Brazel, Anthony J. "Dust and Climate in the American Southwest." In Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, 65–96. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0995-3_3.

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Kambezidis, H. D., A. G. Paliatsos, N. Kappos, and B. Kasselouri. "A Case of African Dust Transport over Athens Captured by a Ceilometer." In Advances in Meteorology, Climatology and Atmospheric Physics, 1011–18. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-29172-2_141.

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Būcher, A. "Fallout of Saharan Dust in the Northwestern Mediterranean Region." In Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, 565–84. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0995-3_24.

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Joussaume, S. "Desert Dust and Climate : An Investigation Using an Atmospheric General Circulation Model." In Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, 253–63. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0995-3_10.

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Pye, K. "Processes of Fine Particle Formation, Dust Source Regions, and Climatic Changes." In Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, 3–30. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0995-3_1.

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Tetzlaff, G., R. Arimoto, G. Bergametti, G. Coude-Gaussen, G. A. d’Almeida, G. Eglinton, F. Grousset, L. Schütz, F. Sirocko, and L. Tomadin. "Dust Composition and Factors Controlling it: Evidence from Aerosols and Sediments." In Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport, 869–71. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0995-3_38.

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Conference papers on the topic "Atmospheric dust transport"

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Kalinskaya, Darya V., and Alla Varenik. "The research of the dust transport impact on the biogeochemical characteristics of the Black Sea surface layer." In XXV International Symposium, Atmospheric and Ocean Optics, Atmospheric Physics, edited by Gennadii G. Matvienko and Oleg A. Romanovskii. SPIE, 2019. http://dx.doi.org/10.1117/12.2540432.

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Surmava, Aleksandre, Demuri Demetrasvili, Vepkhia Kukhalashvili, and Natia Gigauri. "NUMERICAL MODELLING OF DUST DISTRIBUTION IN THE ATMOSPHERE OF A CITY WITH COMPLEX RELIEF." In GEOLINKS International Conference. SAIMA Consult Ltd, 2020. http://dx.doi.org/10.32008/geolinks2020/b1/v2/04.

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Microscale processes of dust distribution in the city of Tbilisi with a very complex topography are modeled using a 3D regional model of atmospheric processes and numerical integration of the transport-diffusion equation of the impurity. The Terrain-following coordinate system is used to take into account the influence of a very complex relief on the process of atmospheric pollution. Modeling is carried out using horizontal grid steps of 300 m and 400 m along latitude and longitude, respectively. The cases of the stationary background eastern and western weak winds are considered. In the model, motor transport is considered as a nonstationary source of pollution from which dust is emitted into the atmosphere. Modelling of dust micro-scale diffusion process showed that the city air pollution depends on spatial distribution of the main sources of city pollution, i.e. on vehicle traffic intensity, as well as on spatial distribution of highways, and micro-orography of city and surrounding territories. It is shown that the dust pollution level in the surface layer of the atmosphere is minimal at 6 a.m. Ground-level concentration rapidly grows with increase of vehicle traffic intensity and by 12 a.m. reaches maximum allowable concentration (MAC = 0.5 mg/m3) in the vicinity of central city mains. From 12 a.m. to 9 p.m. maximum dust concentration values are within the limits of 0.9-1.2 MAC. In the mentioned time interval formation of the highly dusty zones, and slow growth of their areas and value of ground-level concentrations take place. These zones are located in both central and peripheral parts of the city. Their disposition and area sizes depend on spatial distribution of local wind generated under action of complex terrain, as well as on the processes of turbulent and advective dust transfer. From 9 to 12 p.m. reduction of dust pollution and ground-level concentration takes place. After the midnight city dust pollution process continues quasi-periodically. As result of the analysis of vertical distribution of dust concentration is obtained that a basic dust mass emitted into the atmosphere is located in the 100 m surface layer. Concentration value in the upper part of this layer reaches 0.8 MAC and rapidly decreases with altitude increase.
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Tong, Xiaoling. "Numerical Modeling of Dust Transport Around Moving Vehicles in Unsteady Atmospheric Boundary Layer Using Precursor Simulation." In AIAA Scitech 2021 Forum. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2021. http://dx.doi.org/10.2514/6.2021-1541.

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Charles, Leona, Barry Gross, Yonghua Wu, Viviana Vladutescu, Fred Moshary, and Sam Ahmed. "Atmospheric transport of smoke and dust particulates and their interaction with the Planetary Boundary Layer as observed by multi-wavelength lidar and supporting instrumentation." In Optical Engineering + Applications, edited by Upendra N. Singh. SPIE, 2007. http://dx.doi.org/10.1117/12.731943.

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Gelain, Thomas, Laurent Ricciardi, and François Gensdarmes. "Implementation of a Particle Resuspension Model in a CFD Code: Application to an Air Ingress Scenario in a Vacuum Toroidal Vessel." In 2020 International Conference on Nuclear Engineering collocated with the ASME 2020 Power Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/icone2020-16139.

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Abstract During a loss of vacuum accident (LOVA), dust particles that will be present in the future tokamak ITER are likely to be resuspended, inducing a risk for explosion and airborne contamination. Evaluating the particle resuspension/deposition and resulting airborne concentration in case of a LOVA is therefore a major issue and it can be investigated by using a CFD code. To this end, this article presents the implementation of a resuspension model in a CFD code (ANSYS CFX) and its application to an air ingress in a vacuum toroidal vessel with a volume comparable to ITER one. In the first part of the article, the Rock’n Roll model and its operational version with the Biasi’s correlation is presented. The second part of the article will be devoted to the implementation of the Rock’n’Roll model in ANSYS CFX for constant friction velocities and its adaptation to non-constant friction velocities. Finally, the paper presents the simulations obtained on the particle resuspension for an air ingress scenario in a large vacuum vessel. This case is particularly interesting and non-intuitive because as the initial pressure is reduced, the particle behavior is different from that at atmospheric pressure. Further, a competition between airflow forces and gravitational force occurs, due to the low pressure environment, potentially restricting the resuspension, and the pressure influence also has to be taken into account in the particle transport and deposition (Nerisson, 2011). Three particle diameters were studied allowing to show the evolution of the resuspension with this parameter and to calculate dust resuspension rates and airborne fractions during the air ingress.
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Humphries, Larry, Brad Beeny, David Louie, Hossein Esmaili, and Michael Salay. "Non-LWR Model Development for the MELCOR Code." In 2018 26th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icone26-82415.

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MELCOR is a fully-integrated, system-level computer code developed by Sandia National Laboratories (SNL) for the Nuclear Regulatory Commission (NRC) with the primary objective of modeling the progression of severe accidents in light water nuclear power plants [1,2,3]. Since the project began in 1982, MELCOR has undergone continuous development to address emerging issues, process new experimental information, and create a repository of knowledge on severe accident phenomena. This paper summarizes model development specifically developed for non-LWR applications such as high temperature gas reactors (HTGR), sodium fast reactors (SFR) and molten salt reactors (MSR). Beginning in 2008, active development work began on HTGR modeling in MELCOR. Models were developed for helium gas thermodynamics, oxidation of graphite, thermal hydraulics and heat transfer for both prismatic and pebble bed designs, cavity cooling systems, fuel failure and fission product release, graphite dust generation, and aerosol transport, deposition, and resuspension. In 2013, work commenced on the development of modeling capabilities for sodium fast reactors. This development included the addition of sodium as a working fluid as well as the addition of models for simulating containment fires (both spray and pool) as well as sodium atmospheric chemistry. Validation of these new models has been completed and code-to-code comparisons with the CONTAIN/LMR code has been performed. Work continues as development of sodium concrete interaction models is now underway. In 2017, work began on adding capabilities for molten salt reactors. A new equation of state for FLIBE coolant has been successfully tested in MELCOR and is now undergoing validation against experiments. The alternate working fluid model has also been extended to permit both water and one alternate condensable working fluid in the same input model.
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Jena, Sofen K., and Swarup K. Mahapatra. "Effect of Participating Medium Radiation and Nano-Fluidic Behaviour of Atmospheric Aerosol on Natural Convection of Industrial Dusty Air." In ASME 2013 4th International Conference on Micro/Nanoscale Heat and Mass Transfer. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/mnhmt2013-22259.

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The current study is focused on thermal radiation interaction with the natural convection of atmospheric brown cloud (ABC). The current study puts emphasis on ultra fine carbon-black particle suspension of several nano meter range along with some pollutant gas mixture with atmospheric air. The numerical simulation of double diffusive thermo-gravitational convection of ABC is done with Hide and Mason laboratory model for atmosphere. The effect of flow circulation is simulated by setting different value of buoyancy ratios. The effect of participating media radiation has been investigated for various values of optical depth. The governing equations, describing circulation of ABC are solved using modified Marker and Cell method. Gradient dependent consistent hybrid upwind scheme of second order is used for discretization of the convective terms. Discrete ordinate method, with S8 approximation is used to solve radiative transport equation. Comprehensive studies on controlling parameters that affect the flow and heat transfer characteristics have been addressed. The results are provided in graphical and tabular form to delineate the flow behavior and heat transfer characteristics.
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Mazumder, M. K., R. Sharma, A. S. Biris, S. Trigwell, M. N. Horenstein, and M. M. Abbas. "Electrostatic and Gravitational Transport of Lunar Dust in the Airless Atmosphere of the Moon." In 2008 IEEE Industry Applications Society Annual Meeting (IAS). IEEE, 2008. http://dx.doi.org/10.1109/08ias.2008.124.

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Ellis, Hershle, Chase Casher, Jamal Longwood, Abel Taye, Laura Ruhala, and Richard Ruhala. "Lunar Cargo Transportation (LuCaT): Semi-Autonomous Vehicle With Suspended Cable and Solar Power." In ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-24197.

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Abstract NASA is planning to send astronauts to the moon and then establish sustainable lunar exploration during the 21st Century under the Artemis program. The lunar south pole target site will need ground transportation to transport materials such as lunar ice from one location to another. This paper explores an alternative transportation system that is based on earth aerial tramways, which involves a chassis, wheels, drivetrain, and elevated cables with supporting structure. The wear of regolith lunar dust and the difficulties in traversing the uneven lunar terrain are reduced. Also, the speed and size of the cargo being transported should be superior to the lunar roving vehicle. By implementing a drivetrain system powered by solar energy, long term power generation and vehicle operation is achieved in the south polar region, which remains in sunlight at near horizontal incidence during the lunar cycle. Because of the extreme high and low temperatures of the moon, strength of materials that vary with temperature must be considered. The internal components of the vehicle and the chassis are protected by a lightweight shell. On earth, heat generated by electric charging and use of batteries can be removed by convection with the surrounding air. The lunar atmosphere presents a unique problem of possessing virtually no heat transfer through convection, while solar radiation will add or remove heat more extremely than earth-based conditions. A thermal control system is designed to manage the battery waste heat, utilizing optical solar reflectors and an internal conductive cooling system.
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Parozzi, F., and S. Paci. "Development and Validation of the ECART Code for the Safety Analysis of Nuclear Installations." In 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/icone14-89275.

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ECART can simulate the thermal-hydraulic behavior of LWR and GCR plants under severe accident conditions together with the transport of radiotoxic substances. This tool is still under improvement and assessment for new applications in non-nuclear risk studies, new advanced and fusion reactors. As regards accidents with fires within closed environments, specific models can simulate both thermal and chemical processes, accounting for combustion of gases and solids, as well as pool fires. The radiative heat transfer and the action of water sprays on atmosphere cooling and aerosol removal are properly taken into account, as verified by comparing the code predictions to full-scale experiments and to the consequences of fire accidents really occurred. About its application on tokamak fusion plants, a large validation activity is underway, mainly based on the analyses of ad hoc experimental programs or code benchmark promoted inside EURATOM Fusion Technology Programme. The correct simulation of the main phenomena occurring in ICE and STARDUST facilities, as well as the comparison with the results of codes employed in the fusion safety studies, demonstrates the applicability of ECART models in performing a realistic prediction of the whole incidental sequence, accounting both thermal-hydraulics and dust transport also inside fusion plants.
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Reports on the topic "Atmospheric dust transport"

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Gallagher, Alex, Sandra LeGrand, Taylor Hodgdon, and Theodore Letcher. Simulating environmental conditions for Southwest United States convective dust storms using the Weather Research and Forecasting Model v4.1. Engineer Research and Development Center (U.S.), August 2022. http://dx.doi.org/10.21079/11681/44963.

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Dust aerosols can pose a significant detriment to public health, transportation, and tactical operations through reductions in air quality and visibility. Thus, accurate model forecasts of dust emission and transport are essential to decision makers. While a large number of studies have advanced the understanding and predictability of dust storms, the majority of existing literature considers dust production and forcing conditions of the underlying meteorology independently of each other. Our study works to-wards filling this research gap by inventorying dust-event case studies forced by convective activity in the Desert Southwest United States, simulating select representative case studies using several configurations of the Weather Research and Forecasting (WRF) model, testing the sensitivity of forecasts to essential model parameters, and assessing overall forecast skill using variables essential to dust production and transport. We found our control configuration captured the initiation, evolution, and storm structure of a variety of convective features admirably well. Peak wind speeds were well represented, but we found that simulated events arrived up to 2 hours earlier or later than observed. Our results show that convective storms are highly sensitive to initialization time and initial conditions that can preemptively dry the atmosphere and suppress the growth of convective storms.
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