Dust Emission Research Articles

The emission, transport, and impacts of the extreme Saharan dust storm of 2015

Abstract. ​​​​​​​Each summer, the Saharan Air Layer (SAL) transports massive amounts of mineral dust across the Atlantic Ocean, affecting weather, climate, and public health over large areas. Despite the considerable impacts of African dust, the causes and impacts of extreme trans-Atlantic African dust events are not fully understood. The “Godzilla” trans-Atlantic dust event of 2020 has been extensively studied, but little is known about other similar events. Here, we examine the June 2015 event, the second strongest trans-Atlantic African dust event that occurred during the summers from 2003–2022. This event was characterized by moderately high dust emissions over western North Africa and an extremely high aerosol optical depth (AOD) over the tropical North Atlantic. The high dust loading over the Atlantic is associated with atmospheric circulation extremes similar to the Godzilla event. Both the African easterly jet (AEJ) and Caribbean low-level jet (CLLJ) have greatly intensified, along with a westward extension of the North Atlantic subtropical high (NASH), all of which favor the westward transport of African dust. The enhanced dust emissions are related to anomalously strong surface winds in dust source regions and reduced vegetation density and soil moisture across the northern Sahel. The dust plume reduced net surface shortwave radiation over the eastern tropical North Atlantic by about 25 W m−2 but increased net longwave flux by about 3 W m−2. In contrast to the Godzilla event, the 2015 event had minor air quality impacts on the US, partially due to the extremely intensified CLLJ that dispersed the dust plume towards the Pacific.

Long-range transport impact of a severe dust storm over the Yangtze River Basin region and its modeling sensitivity to dust emission scheme

Dust storms frequently occur in the spring over East Asia, affecting southern Mongolia and northeast China. An exceptionally powerful dust storm occurred in East Asia from March 14th to March 18th, 2021. To investigate the ability of climate models to simulate severe dust storms, we employed the Weather Research Forecast model coupled with chemistry (WRF-Chem) with Goddard Chemistry Aerosol Radiation and Transport (GOCART), SHAO and KOK dust emission schemes to simulate the evolution of this event and to characterize dust aerosols long-range transport. Results showed that this storm was caused by a Mongolian cyclone depicted at 850 hPa with a cold front, which swept dust aerosols southeastward across southern Mongolia to northeast China. Model evaluation with satellite-retrieved Aerosol Optical Depth (AOD) and observational PM10 concentrations revealed that the SHAO dust emission scheme performed better in simulating spatial and temporal distribution of AOD over the Gobi Desert (GD) but overestimated them over Taklimakan Desert (TD). In contrast, the GOCART dust emission scheme underestimated AOD over most areas except the Taklimakan Desert; the KOK dust emission scheme overestimated them over both TD and GD. Overall, the SHAO dust emission scheme had good performance in simulating the surface PM10 concentrations over the Yangtze River Basin (YRB) and depicted an increase in PM10 concentrations, which denoted the transport of dust aerosols over YRB. As a better description of the physical process of dust emission flux over the eastern region of the Gobi Desert, the SHAO dust emission scheme depicted well the spatial and temporal evolution of dust plume episodes, especially over northeast China and YRB. The significant differences in dust emission fluxes between the three dust emission schemes were attributed to the sensitivity of threshold friction velocity and erodibility factor. Thereunto, the SHAO dust emission scheme incorporated well soil particle size distribution and threshold velocity to produce the dust emission flux, which allowed higher dust emission flux over the eastern GD and under strong southwesterly transported dust aerosols to East Central China's region of North China Plain (NCP) and YRB. This study will help further the simulation of extreme dust events more accurately and the exploration of climate change's effect on dust events over East Asia.

Study on photovoltaic combined air source heat pump heating system under typical meteorological conditions

Abstract This paper proposes a photovoltaic (PV) combined air source heat pump heating system for rural areas in severe cold regions of northern China, where the current clean heating methods have high costs and low efficiency. The paper uses meteonorm8 and TRNSYS software to derive the typical meteorological parameters and simulate the system performance in a guard room in Shenyang city. The paper analyzes the heat pump power consumption, PV cell power generation, and economic and environmental benefits of the system under different outdoor temperatures in the heating season. The results show that the system can meet the heating demand and maintain a comfortable indoor temperature, with an annual cost of 1603 RMB, which is 61.33% lower than a single heat pump system. The system can also reduce the emissions of carbon dioxide, sulfur dioxide, and dust by 2619.43 kg, 10.78 kg, and 6.91 kg per year, respectively, demonstrating its economic feasibility and environmental contribution.

Resolving high-z galaxy cluster properties through joint X-ray and millimeter analysis: Case study of SPT-CLJ0615-5746

We present a joint millimetric and X-ray analysis of hot gas properties in the distant galaxy cluster SPT-CLJ0615-5746 (z = 0.972). Combining Chandra observations with the South Pole Telescope (SPT) and Planck data, we performed radial measurements of thermodynamical quantities up to a characteristic radius of 1.2 R500. We exploited the high angular resolution of Chandra and SPT to map the innermost region of the cluster and the high sensitivity to the larger angular scales of Planck to constrain the outskirts and improve the estimation of the cosmic microwave background and the galactic thermal dust emissions. In addition to maximizing the accuracy of radial temperature measurements, our joint analysis allows us to test the consistency between X-ray and millimetric derivations of thermodynamic quantities via the introduction of a normalization parameter (ηT) between X-ray and millimetric temperature profiles. This approach reveals a substantial high value of the normalization parameter, ηT = 1.45−0.18+0.17, suggesting that the gas halo is aspherical. Assuming hot gas hydrostatic equilibrium within complementary angular sectors that intercept the major and minor elongation of the X-ray image, we infer a halo mass profile that results from an effective compensation of azimuthal variations of gas densities by variations in the ηT parameter. Consistent with earlier integrated X-ray and millimetric measurements, we infer a cluster mass of M500HE = 10.67−0.50+0.62 1014 M⊙.

Dust emission, transport, and deposition in central Iran and their radiative forcing effects: A numerical simulation

In this study, WRF-Chem was used to analyze the radiative forcing, deposition, emission and transport of mineral dust during three severe dust events in central Iran, specifically in Yazd area. The results showed that central Iran is predominantly influenced by internal dust sources. During these events, the amount of dust emissions and depositions in Iran were about 740–1400 Gg and 50–90 Gg, respectively. In Yazd, the dust emissions and depositions were about 34–104 Gg and 8–16 Gg, respectively, originating from the Ardakan plain and Dasht-e-kavir. In order to analyze the effect of dust on the climate, it was found that dust resulted a surface cooling by shortwave and longwave radiative forcing in the range of −11 to −21 W/m2 and 6.7–13.9 W/m2, respectively, over Yazd province. In the atmosphere, radiative forcing led to the warming effect with shortwave and longwave radiative forcing in the range of 10.5–19.7 W/m2 and -6 to −11 W/m2 over Yazd, respectively. Furthermore, it was demonstrated that the radiative forcing associated with dust also had an impact on meteorological parameters. The results showed that this phenomenon influenced microphysical processes and mitigated the climatic effects of dust.

Spatiotemporal analysis of sand and dust emission point sources detected from satellite imagery in Syria, Jordan, and Iraq

This study utilized MODIS true color satellite imagery to analyse blowing sand and dust events dynamics in the Middle East from 2010 to 2021, focusing on Syria, Iraq, and Jordan. A total of 4923 dust point sources were detected, with a significant concentration (~90 %) located within the Tigris-Euphrates Basin (Nearest Neighbor Ratio = 0.41, р < 0.001). Land cover analysis revealed that bare land, comprising most of the study area, was the predominant source of dust emissions. Wetlands, though only constituting about 1 % of the area, showed the highest frequency of dust sources per unit area, highlighting their role as critical dust emission hotspots. The study emphasizes the impact of drought and anthropogenic factors, such as poor land management, on blowing dust intensity. It suggests the necessity of strategic land management practices, including re-vegetation of arid areas, reducing soil exposure, and implementing wind erosion control measures. To effectively address the transboundary nature of dust emissions, the findings underscore the importance of fostering regional cooperation through mechanisms such as shared environmental monitoring and data exchange platforms, joint management of cross-border natural resources, and collaborative policy making.

Relative alignments between magnetic fields, velocity gradients, and dust emission gradients in NGC 1333

Relative alignments between magnetic fields, velocity gradients, and dust emission gradients in NGC 1333

An Evaluation of the Dust Emission Characteristics of Typical Underlying Surfaces in an Aeolian Region in the Middle Reaches of the Yarlung Zangbo River on the Qinghai–Tibet Plateau

Some of the most severe aeolian damage occurs along the middle reaches of the Yarlung Zangbo River in Tibet. Dust emission amounts (DEAs) are often used to assess aeolian damage; however, the research on DEAs in this area is currently almost blank. This article uses field-measured wind speed data from 2021 to 2022 in the Shannan wide valley area, combined with the Gillette dust emission estimation model to quantitatively determine the contributions of three surface types (riverbank quicksand area, foothill sand dunes, and the river floodplain vegetation area) to DEAs in the research area. The influence of surface characteristics on DEAs is analyzed and discussed. The results show the following: (1) The threshold friction velocity (u*t) in the riverbank quicksand area, foothill sand dunes, and the river floodplain vegetation area is 30.6 cm/s, 71.2 cm/s, and 85.6 cm/s, respectively, the threshold velocity (ut) is 6.1 m/s, 7.0 m/s, and 7.5 m/s, respectively, and the vegetation area is 2.8 times and 1.3 times that of the quicksand area, respectively. (2) The DEAs were in the following order: the riverbank quicksand area (652.9 t/km2) &gt; foothill sand dunes (326.5 t/km2) &gt; the river floodplain vegetation area (107.8 t/km2), the riverbank quicksand area is about 6.1 times that of the river floodplain vegetation area, and DEAs are a significant seasonal distribution: winter (44.7%) &gt; spring (28.3%) &gt; autumn (15.7%) &gt; summer (11.3%). (3) The DEAs from the dusty weather were in the following order: blowing sand (60.2%) &gt; sandstorms (28.6%) &gt; gusty winds (11.2%). (4) The DEAs increase with the increase in the average wind speed greater than 6.1 m/s, but the increase rate is obviously different, which showed that Changguo and Azha are greater than Sangyesi, Duopazhang, Sangri, and Senburi. At approximately the same average wind speed greater than 6.1 m/s, the DEAs in the quicksand area are much greater than in the vegetation area.

Paleoclimate Controls on West African Dust Inferred from Rb/Sr and Si/Al of Sediments in an Eastern Equatorial Atlantic Marine Core

Increased dust emissions from dryland areas and their effects on human health, ecosystem viability, and environmental change are a global concern in the face of the growing climate crisis. Dust plume emissions from the West African landmass, Sahara, and Sahel areas comprise a major fraction of the global aerosol budget. Dust plume intensity is closely related to regional winds (e.g., Harmattan, Sahara Air Layer), the Intertropical Convergence Zone, monsoonal seasonality, marine currents, and physiography. To study terrigenous material emitted from the continent over the last ~260 kyr (late Quaternary), we used X-ray fluorescence spectroscopy (XRF) to analyze a ~755 cm long marine sediment core from the eastern equatorial Atlantic Ocean, resulting in nearly 1400 discrete measurements. Spectral analysis results suggest that concentrations of elements (Rb, Sr, Si, Al) preserved in the sediments are correlated to different types of orbital climate forcing. Chemical weathering intensity indicated by the Rb/Sr ratio was sensitive to seasonal insolation variations controlled by precession cycles (23–18 kyr), which presumably reflects the relationship between monsoonal rainfall and sensible heating of the continent. Spectral analysis of silicate mineral grain size (Si/Al) showed significant 40 kyr cycles that were paced by obliquity. Based on these data, we infer that winter tradewind activity accelerated in response to the intertropical insolation gradient induced by high obliquity. High Rb/Sr ratios during the last glacial maximum and penultimate glacial maximum may have been due to a predominance of mechanical weathering over chemical weathering under dry/cool climates or the dissolution of Sr-bearing carbonates by corrosive glacial bottom waters.

H i content at cosmic noon – a millimetre-wavelength perspective

ABSTRACT In order to understand galaxy growth evolution, it is critical to constrain the evolution of its building block: gas. Mostly comprised by Hydrogen in its neutral (H i) and molecular (H$_2$) phases, the latter is the one mostly directly associated to star formation, while the neutral phase is considered the long-term gas reservoir. In this work, we make use of an empirical relation between dust emission at millimetre wavelengths and total gas mass in the interstellar medium (M$_{\rm HI}$ plus M$_{\rm H_2}$) in order to retrieve the H i content in galaxies. We assemble an heterogeneous sample of 335 galaxies at $0.01\lt z\lt 6.4$ detected in both mm-continuum and carbon monoxide (CO), with special focus on a blindly selected sample to retrieve H i cosmological content when the Universe was $\sim 2-6\,$ Gyr old ($1\lt z\lt 3$). We find no significant evolution with redshift of the M$_{\rm HI}$/M$_{\rm H_2}$ ratio, which is about $1-3$ (depending on the relation used to estimate M$_{\rm HI}$). This also shows that M$_{\rm H_2}$-based gas depletion times are underestimated overall by a factor of $2-4$. Compared to local Universe H i mass functions, we find that the number density of galaxies with M$_{\rm HI}\gtrsim 10^{10.5}\,$M$_\odot$ significantly decreased since 8–12 Gyr ago. The specific sample used for this analysis is associated to 20–50 per cent of the total cosmic H i content as estimated via Damped Lyman-$\alpha$ Absorbers. In IR luminous galaxies, H i mass content decreases between $z\sim 2.5$ and $z\sim 1.5$, while H$_2$ seems to increase. We also show source detection expectations for SKA surveys.

MINDS: The DR Tau disk. II. Probing the hot and cold H_2O reservoirs in the JWST-MIRI spectrum

The Medium Resolution Spectrometer (MRS) of the Mid-InfraRed Instrument (MIRI) on the James Webb Space Telescope (JWST) gives insights into the chemical richness and complexity of the inner regions of planet-forming disks. Several disks that are compact in the millimetre dust emission have been found by Spitzer to be particularly bright in H_2O which is thought to be caused by the inward drift of icy pebbles. Here, we analyse the H_2O -rich spectrum of the compact disk DR Tau using high-quality JWST-MIRI observations. We infer the H_2O column densities (in cm$^ $) using methods presented in previous works, as well as introducing a new method to fully characterise the pure rotational spectrum. We aim to further characterise the abundances of H_2O in the inner regions of this disk and its abundance relative to CO . We also search for emission of other molecular species, such as CH_4 NH_3 CS H_2 SO_2 and larger hydrocarbons; commonly detected species, such as CO CO_2 HCN and C_2H_2 have been investigated in our previous paper. We first use 0D local thermodynamic equilibrium (LTE) slab models to investigate the excitation properties observed in different wavelength regions across the entire spectrum, probing both the ro-vibrational and rotational transitions. To further analyse the pure rotational spectrum (geq 10 $ mu $m), we use the spectrum of a large, structured disk (CI Tau) as a template to search for differences with our compact disk. Finally, we fit multiple components to characterise the radial (and vertical) temperature gradient(s) present in the spectrum of DR Tau. The 0D slab models indicate a radial gradient in the disk, as the excitation temperature (emitting radius) decreases (increases) with increasing wavelength, which is confirmed by the analysis involving the large disk template. To explain the derived emitting radii, we need a larger inclination for the inner disk ($i agreeing with our previous analysis on CO . From our multi-component fit, we find that at least three temperature components ($T_1 K, $T_2 K, and $T_3 K) are required to reproduce the observed rotational spectrum of H_2O arising from the inner $R_ em au. By comparing line ratios, we derived an upper limit on the column densities (in $) for the first two components of $ (N) within sim 1.2 au. We note that the models with a pure temperature gradient provide as robust results as the more complex models, which include spatial line shielding. No robust detection of the isotopologue H_2 ^ O can be made and upper limits are provided for other molecular species. Our analysis confirms the presence of a pure radial temperature gradient present in the inner disk of DR Tau, which can be described by at least three components. This gradient scales roughly as $ R_ em $ in the emitting layers, in the inner 2 au. As the observed H_2O is mainly optically thick, a lower limit on the abundance ratio of H_2O CO sim 0.17 is derived, suggesting a potential depletion of H_2O . Similarly to previous work, we detect a cold H_2O component ($T K) originating from near the snowline, now with a multi-component analysis. Yet, we cannot conclude whether an enhancement of the H_2O reservoir is observed following radial drift. A consistent analysis of a larger sample is necessary to study the importance of drift in enhancing the H_2O abundances.

Spatial Source Contribution and Interannual Variation in Deposition of Dust Aerosols Over the Chinese Loess Plateau

AbstractThe Chinese Loess Plateau (CLP) in northern China is home to one of the most prominent loess records in the world, reflecting past eolian dust activity in East Asia. However, their interpretation is hampered by ambiguity in the origin of loess‐forming dust and an incomplete understanding of the circulation forcing dust accumulation. In this study, we used a novel modeling approach combining a dust emission model FLEXDUST with simulated back trajectories from FLEXPART to trace the dust back to where it was emitted. Over 21 years (1999–2019), we modeled back trajectories for fine (∼2 μm) and super‐coarse (∼20 μm) dust particles at six CLP sites during the peak dust storm season from March to May. FLEXPART source‐receptor relationships are combined with the dust emission inventory from FLEXDUST to create site‐dependent high‐resolution maps of the source contribution of deposited dust. The nearby dust emission areas were found to be the main source of dust to the CLP. Dust deposition across the CLP was found to predominantly occur via wet removal, with also some super‐coarse dust from distant emission regions being wet deposited following high‐level tropospheric transport. The high topography located on the downwind side of the emission area plays an essential role in forcing the emitted super‐coarse dust upward. On an interannual scale, the phase of the Arctic Oscillation in the preceding winter was found to have a strong association with the spring deposition rate on the CLP, while the strength of the East Asian Winter Monsoon was less influential.

A new approach to dust source mapping using visual interpretation and object-oriented segmentation of satellite imagery

The emission of dust particles, mainly from arid and semi-arid lands, as a result of climate change and human activities, is known to be a global issue. Identifying dust emission sources is the first key step in dealing with the hazardous consequences of this rising phenomenon. This study is an attempt to address one of the major challenges in mapping dust emission sources. Accordingly, an innovative approach based on visual interpretation of multi-temporal MODIS-Terra/Aqua imagery and object-oriented image segmentation techniques has been developed and implemented in the study areas of the Tigris and Euphrates basin and eastern Iran. This approach takes advantage of land surface characteristics (i.e., dust drivers), including geomorphology, soil, land use/cover, and land surface radiation, to attribute dust emission hotspots to their corresponding areas using multi-source remote sensing data. The results show that the multi-resolution segmentation algorithm with optimized parameters can identify homogeneous segments corresponding to dust emission sources in the study areas with an average spatial agreement of ∼92% compared to the reference areas. Our findings emphasize the robustness and generalizability of the proposed approach, and its capabilities can be used in a complementary way with visual interpretation of satellite images to map dust sources with high spatial accuracy.

Thermal performance of solar ground source heat pump system for rural buildings in Chinese cold zone

In response to China's national policy of “achieving carbon peak by 2030 and carbon neutrality by 2060″, and to promote the heating system of rural buildings in China's severe cold zone. Two heating schemes of the GSHP (Ground Source Heat Pump) system and the SGSHP (Solar Ground Source Heat Pump) system are designed and simulated for a single rural residential building in Harbin city. The results present that the outlet temperature of buried pipe in SGSHP system is 13.86 % higher than that in GSHP system, and coefficient of performance (COP) correspondingly increases 9.2 %. There is a better comprehensive performance for the SGSHP system in cold climates. The standard coal consumption of SGSHP system is about 72.35 % less than that of biomass boiler system, showing a greater energy efficiency. Compared to the local conventional biomass boiler system, the dynamic cost payback period of the SGSHP system amounts to 11 years, while yielding a net present value (NPV) of 10,800 CNY throughout the project's life cycle. The emissions of CO2, SO2, and dust are reduced by 2617.13 kg, 19.38 kg, and 14.535 kg respectively. The results indicate a great overall performance of the SGSHP system for residential heating in the cold climate zone. This research offers an energy efficient and eco-friendly alternative for the space heating of Chinese rural buildings in cold climates.

Estimation of Particulate Matter (PM10) Over Middle Indo-Gangetic Plain (Patna) of India: Seasonal Variation and Source Apportionment

Despite extensive research on particulate matter (PM) pollution in India’s Indo-Gangetic Plain (IGP), source apportionment remains challenging. This study investigates the effect of particulate matter (PM10)-associated water soluble inorganic ions (WSIIs) on ambient air concentration across the middle IGP from January to December 2018. Moreover, the seasonal fluctuation and chemical characterization of PM10 were assessed for the year 2018. The results revealed a high concentration of PM10 (156 µg/m3), exceeding the WHO and National Ambient Air Quality Standard (NAAQS) limits. The highest PM10 levels were observed during autumn, winter, summer, and the rainy season. The study identified SO42− and NH4+ as the most common WSIIs, constituting 46% and 23% of the total WSIIs. Source apportionment analysis indicated that street dust, biomass burning, and vehicle and industrial emissions together with secondary formation significantly contributed to IGP’s PM pollution. Additionally, the investigation of air mass back trajectory suggests that air quality in IGP is largely influenced by eastern and western Maritime air masses originated from the Arabian Sea, the Bay of Bengal, Gujarat, Afghanistan, Pakistan, and Bangladesh.

Assessment of seasonal forecasting potential for springtime Asian dust in South Korea using the KMA global seasonal forecasting system

This study aims to assess the potential of seasonal forecasting for springtime Asian dust days in South Korea using the Korea Meteorological Administration's Global Seasonal Forecasting System version 6 (KMA GloSea6). The system demonstrated similar predictive performance for springtime Asian dust days compared to GloSea5-ADAM, which incorporates the Asian Dust and Aerosol Model's emission algorithm into GloSea5. While KMA GloSea6 exhibited strong wind, cold, and moist biases in the Asian dust source region during the spring of the hindcast period, similar to GloSea5-ADAM, it showed an improved spatial distribution of ACC. The anomaly correlation coefficient for the annual variability of Asian dust occurrence frequency anomalies in the dust source region was also similar, with values of 0.41 for KMA GloSea6 and 0.43 for GloSea5-ADAM. Furthermore, in evaluating the seasonal forecasting of springtime Asian dust days using hindcast datasets, KMA GloSea6 accurately predicted 12 out of 24 instances, resulting in a forecast accuracy of 0.5, consistent with GloSea5-ADAM. When applying the criteria to spring 2022 and 2023 forecast data not used in the derivation, the predicted Asian dust days of 6.14 days in spring 2022 led to a “Near normal” prediction, differing from the observed “Below normal.” However, the spatial distribution showed “Below normal” conditions, aligning with observations in some areas. In spring 2023, the predicted 9.78 Asian dust days led to an “Above normal” prediction, consistent with observed conditions. These findings will contribute to advancing seasonal Asian dust forecasting in South Korea.

Features of the chemical composition of fine suspended particles in the atmospheric air of residential and industrial zones of the city of Sibay, Republic of Bashkortostan

Introduction. Atmospheric particulate matter as a negative environmental factor can be a significant hazard depending on their size, morphometric and physicochemical characteristics. The purpose of the study. To investigate the elemental composition of finely dispersed suspended particles in the atmospheric air of the industrial zones of the mining center of the Bashkir Trans-Urals - the city of Sibay. Materials and methods. Air sampling was carried out in the industrial area of ​​Sibay using an AVA-3-240/180-01 automatic three-channel air aspirator with AFA-VP-20 filters. Microscopy of samples and determination of the elemental composition of dust emissions were carried out at the Interdisciplinary Center “Analytical Microscopy” of the Kazan Federal University (Kazan) on a universal analytical complex for scanning field emission electron microscopy Merlin (Carl Zeiss). Results. On electron micrographs, there were identified particles of various sizes, mostly round in shape with clear edges, located solitary. In the automatic mode of processing the spectra, the peaks of the elements in the spectrum were automatically recognized and identified. In addition to carbon and oxygen, the calcium, iron, silicon, potassium, aluminium, copper, sulphur, sodium and magnesium are main chemical constituents of particulate matter encountered at all sampling points. Zinc was present in dust samples at three points, scandium, titanium, cobalt, barium, and manganese – only at one point. The possibility of the relation between the content of fine particles in the air and the increased incidence of cardiovascular, bronchopulmonary diseases, including asthma, in the population of Sibay is discussed. Limitations. The study of the elemental composition of fine dust in the city of Sibay was carried out using atmospheric air samples taken at 5 points located in residential and industrial areas. Conclusion. The increased content of fine particles in the atmospheric air of the city of Sibay increases the risks of respiratory and cardiovascular diseases, as well as other health abnormalities, in the population permanently residing near industrial zones. The obtained data on the parameters of dust particles are the basis for assessing the share contribution of industrial enterprises to air pollution and making management decisions to improve the environmental situation in the industrial center of the mining region.

Dust Emissions on Mars From Phoenix Lidar Measurements in Relation to Local Meteorological Conditions

AbstractThe diurnal cycle of dust aerosols on Mars is studied by analyzing lidar observations at the Phoenix landing site under cloud‐ and fog‐free conditions and in the absence of elevated, long‐range transported dust layers. There is a pronounced diurnal cycle in the dust‐layer height with minimum heights of 4–6 km occurring between 11:00 and 17:00 local time. The ratio of the aerosol optical depth (AOD) within the lowermost 2 km to the total AOD reaches peak values at the same time. This can be explained by local dust emissions driven by the diurnal cycle of heating and cooling in the boundary layer. Analysis of wind and pressure measurements show that the gustiness of surface winds and the frequency of convective vortices undergo diurnal variations resembling those of AOD, indicating that these processes are the main drivers for local dust emissions.

Substitution of Conventional Vehicles in Municipal Mobility

Among the economic sectors, mobility is showing significant environmental impacts, especially in the use phase of vehicles. By substituting fossil-fuelled propelling systems, environmental impacts such as the Global Warming Potential (GWP) can be reduced. The use of properly designed light electric vehicles (LEVs) significantly reduces further environmental impacts, as well as maintenance costs, which are relevant for a circular economy. For example, the use of low-voltage (42 V) propelling systems enables the maintenance of LEVs in a broader range of existing bicycle workshops. Regarding the environmental impacts, the described LCA results indicate the advantage of LEVs compared with EVs and ICVs, e.g., vehicle weight is found to be a main factor related to environmental impact for each type of vehicle. This implies a reduced need for battery capacity and lower emissions of particulate matter from tire and break abrasion. This study aims to present the application potential of LEVs and the related reduction in environmental impacts. Anonymised inventory lists of municipal vehicle fleets are analysed for quantifying the substitution potential of LEVs in specific use cases. For this purpose, the use phase of vehicles is analysed with a focus on product design for repair and recycling and supplemented by the results of a comparative environmental impact assessment of internal combustion engine vehicles (ICEVs), electric vehicles (EVs), and LEVs. The comparison is made on the premise of similar application requirements. These specifications are the ability of each of the vehicles to transport a maximum of three persons (driver included) or one driver and 250 kg of cargo in 3 m3 over a daily distance of 100 km in urban areas. On this basis, the municipal environmental benefits derived from substituting small vehicles in the form of ICEVs and EVs with LEVs are assessed. The results show that in the field of municipal mobility, a relevant number of conventional small vehicles can be substituted with LEVs. The environmental impacts in categories of the highest robustness level, RL I, that is, Global Warming Potential, fine dust emissions, and Ozone Depletion Potential, can be reduced by LEVs by 50% compared with EVs and by over 50% compared with ICEVs. The strong influence of vehicle weight on the abrasive conditions of tires and brakes is considerable, as shown by reduced fine dust emissions.

Application of triple-branch artificial neural network system for catalytic pellets combustion

On the international level, it is common to act on reducing emissions from energy systems. However, in addition to industrial emissions, low-stack emissions also make a significant contribution. A good step in reducing its environmental impact, is to move to biofuels, including biomass. This paper examines the impact of placing a catalytic system in a retort boiler to minimize emissions of greenhouse gases, dust and other pollutants when burning pellets. The effect of platinum, and oxides of selected metals placed on the deflector as a solid catalyst was studied. Based on the experimental data, a branched artificial neural network was constructed and trained. The routing of three parallel topologies made it possible to achieve high accuracy while keeping the input data relatively simple. The system showed an average error of 3.54% against arbitrary test data. On the basis of experimental data as well as predictions returned by the artificial neural network, recommendations were shown for the catalysts used and their amounts. Depending on the biomass from which the pellet was produced, the experiment suggested the use of titanium or copper oxides. In the case of the neural network, it was able to select a better system, based on platinum, improving emission reductions by up to more than 19%, depending on the type of pellet used.