Toxic potency-adjusted control of air pollution for solid fuel combustion

The combustion of solid fuels, including coal and biomass, is a main anthropogenic source of atmospheric particulate matter (PM). The hidden costs have been underestimated due to lack of consideration of the toxicity of PM. Here we report the unequal toxicity of inhalable PM emitted from energy use in the residential sector and coal-fired power plants (CFPPs). The incomplete burning of solid fuels in household stoves generates much higher concentrations of carbonaceous matter, resulting in more than one order of magnitude greater toxicity than that from CFPPs. When compared with CFPPs, the residential sector consumed only a tenth of solid fuels in mainland China in 2017, but it contributed about 200-fold higher of the population-weighted toxic potency-adjusted PM2.5 exposure risk. We suggest that PM2.5-related toxicity should be considered when making air pollution emission control strategies, and incomplete combustion sources should receive more policy attention to reduce exposure risks.

Perspectives on the Ecological Role of Geophysical Sounds

Humans categorize unwanted sounds in the environment as noise. Consequently, noise is associated with negative human and ecological values, especially when it is derived from an anthropogenic source. Although evidence confirms that many machine-generated anthropogenic sounds have negative impacts on animal behavior and communication, natural sources of non-biological sound, such as wind, rain, running water, and sea waves (geophonies) have also been categorized as noise and are frequently dismissed or mischaracterized in acoustic studies as an outside factor of acoustic habitats rather than an integrated sonic component of ecological processes and species adaptations. While the proliferation of machine-generated sound in the Biosphere has become an intrusive phenomenon in recent history, geophony has shaped the Earth’s sonic landscapes for billions of years. Therefore, geophonies have very important sonic implications to the evolution and adaptation of soniferous species, forming essential ecological and semiotical relationships. This creates a need to distinguish geophonies from machine-generated sounds and how species respond to each accordingly, especially given their acoustic similarities in the frequency spectrum. Here, we introduce concepts and terminology that address these differences in the context of ecoacoustics. We also discuss how Acoustic Complexity Indices (ACIs) can offer new possibilities to quantifiably evaluate geophony in relation to their sonic contest.

Aviation impact on the cirrus ice crystal number using satellite observation

<p align="justify">Aviation outflow is the only anthropogenic source of pollution that is directly emitted into the upper troposphere. This emission has the potential to modify the cloudiness directly by forming linear contrails and indirectly by injecting aerosols, which can act as cloud condensation nuclei (CCN) and ice nucleating particles (INP). Contrail cirrus can persist either in cloud-free supersaturated air, increasing high-cloud cover or inside natural cirrus cloud, and therefore modifying the microphysical properties of already existing cirrus clouds. Even though the situation that an aircraft flies through a natural cirrus is one of the highly probable situations in the upper troposphere, its subsequent impact is unclear with the present state of knowledge. Quantifying such impact is necessary if we are to properly account for the influence of aviation on climate. One main limitation preventing us to better identify these impacts is the lack of height resolved measurements inside the cirrus clouds.</p> <p align="justify">In this study, we used new retrievals from combined satellite cloud radar and lidar (Cloud- Sat/CALIPSO; DARDAR-Nice algorithm), which provide height resolved information of ice crystal number concentration, at intercepts between the CALIPSO ground track and the position of civil aircraft operating between the west coast of the continental United States (Seattle, San Francisco and Los Angeles) and Hawaii during 2010 and 2011 from an earlier study.</p> <p align="justify">Comparing cloudy air behind the aircraft inside the flight track to the adjacent regions and to ahead of the aircraft revealed a notable difference in ice number concentration at 300 m to 540 m beneath the flight height. These differences are derived from the reduction of ice number concentrations as we proceed toward the cloud base in regions unaffected by aviation and the increase of ice crystals as we distance a few hundreds of meters beneath the flight level in the regions affected by aviation.</p>

Abnormal aerosol air pollution in Moscow near the local anthropogenic source in July 2021

The paper analyzes the composition of surface aerosol close to the local intense anthropogenic source of pollution associated with the active phase of demolition of multistorey buildings in the center of Moscow. An abnormal increase in the daytime PM10 aerosol particle concentration to 5 MPC for daily values and to 14 MPC for maximum single values was reinforced by unfavorable meteorological conditions in the middle of July 2021. Preliminary estimation of the power of the dust aerosol source and its effect on the aerosol air pollution in nearby areas of the city is performed. The extreme and background values of the aerosol mass concentration, its elemental composition and particle size distribution during this period are determined. It is necessary to take into account such point pollutant sources in estimating and forecasting environmental conditions in a densely populated city. Keywords: surface aerosol, local anthropogenic source, Moscow, aerosol mass concentration, elemental composition, meteorological conditions

Abnormal aerosol air pollution in Moscow near the local anthropogenic source in July 2021

The paper analyzes the composition of surface aerosol close to the local intense anthropogenic source of pollution associated with the active phase of demolition of multistorey buildings in the center of Moscow. An abnormal increase in the daytime PM10 aerosol particle concentration to 5 MPC for daily values and to 14 MPC for maximum single values was reinforced by unfavorable meteorological conditions in the middle of July 2021. Preliminary estimation of the power of the dust aerosol source and its effect on the aerosol air pollution in nearby areas of the city is performed. The extreme and background values of the aerosol mass concentration, its elemental composition and particle size distribution during this period are determined. It is necessary to take into account such point pollutant sources in estimating and forecasting environmental conditions in a densely populated city. Keywords: surface aerosol, local anthropogenic source, Moscow, aerosol mass concentration, elemental composition, meteorological conditions

Sediment Assessment of the Pchelina Reservoir, Bulgaria

The temporal dynamics of anthropogenic impacts on the Pchelina Reservoir is assessed based on chemical element analysis of three sediment cores at a depth of about 100–130 cm below the surface water. The 137Cs activity is measured to identify the layers corresponding to the 1986 Chernobyl accident. The obtained dating of sediment cores gives an average sedimentation rate of 0.44 cm/year in the Pchelina Reservoir. The elements’ depth profiles (Ti, Mn, Fe, Zn, Cr, Ni, Cu, Mo, Sn, Sb, Pb, Co, Cd, Ce, Tl, Bi, Gd, La, Th and Unat) outline the Struma River as the main anthropogenic source for Pchelina Reservoir sediments. The principal component analysis reveals two groups of chemical elements connected with the anthropogenic impacts. The first group of chemical elements (Mn, Fe, Cr, Ni, Cu, Mo, Sn, Sb and Co) has increasing time trends in the Struma sediment core and no trend or decreasing ones at the Pchelina sampling core. The behavior of these elements is determined by the change of the profile of the industry in the Pernik town during the 1990s. The second group of elements (Zn, Pb, Cd, Bi and Unat) has increasing time trends in Struma and Pchelina sediment cores. The increased concentrations of these elements during the whole investigated period have led to moderate enrichments for Pb and Unat, and significant enrichments for Zn and Cd at the Pchelina sampling site. The moderately contaminated, according to the geoaccumulation indexes, Pchelina Reservoir surface sediment samples have low ecotoxicity.

Geogenic and anthropogenic sources identification and ecological risk assessment of heavy metals in the urban soil of Yazd, central Iran

Urban soil pollution with heavy metals is one of the environmental problems in recent years, especially in industrial cities. The aim of this study is to evaluate the role of geogenic and anthropogenic sources in the urban soil pollution in Yazd, Iran. For this purpose, 30 top-soil (0–10 cm) samples from Yazd within an area of 136.37 Km2 and population of nearly 656 thousand are collected, and the concentration of heavy elements is measured. To evaluate factors affecting the concentration of heavy elements in urban soils and determine their possible sources, Multivariate statistical analysis, including correlation coefficient, principal components analysis (PCA) and cluster analysis (CA) are performed. Enrichment Factor (EF), Geo-accumulation index (Igeo), and Modified potential ecological Risk Index (MRI) are used to assess the level and extension of contamination. Results of this study suggest that As, Cd, Pb and Zn are affected by anthropogenic source, while the concentrations of Fe, Mn, Ni, Cr, Co, Cu and Cs have come from mostly natural geologic sources. As, Cd and Pb are considerably enriched in the area, provided moderately enriched for the elements Mn, Zn and Cu. However, the other heavy elements show minimal enrichment. Igeo reveal that Co, Cr, Cs, Cu, Fe, Mn, Zn and Ni with negative values are unpolluted, Pb posed unpolluted to moderately polluted, and As and Cd represent high polluted. Based on the results of the ecological risk factor, the heavy metals of Mn, Ni, Cr, Zn and Cu have a low ecological risk level. More specifically, we find that Pb shows a moderated ecological risk in 39% of the urban soil in the studied area. As and Cd with respectively 100 and 72% contribution have considerable and very high ecological risk. According to the results of MRI, the area is in a very high ecological risk level, and appropriate management practice is essential to reduce the pollution of heavy elements in this area.

OMI-observed HCHO in Shanghai, China, during 2010–2019 and ozone sensitivity inferred by an improved HCHO ∕ NO₂ ratio

In recent years, satellite remote sensing has been increasingly used in the long-term observation of ozone (O3) precursors and its formation regime. In this work, formaldehyde (HCHO) data from Ozone Monitoring Instrument (OMI) were used to analyze the temporal and spatial distribution of HCHO vertical column densities (VCDs) in Shanghai from 2010 to 2019. HCHO VCDs exhibited the highest value in summer and the lowest in winter, the high VCD being concentrated in western Shanghai. Temperature largely influences HCHO by affecting the biogenic emissions and photochemical reactions, and industry was the major anthropogenic source. The satellite-observed formaldehyde-to-nitrogen dioxide ratio (FNRSAT) reflects that the O3 formation regime had significant seasonal characteristics and gradually manifested as a transitional ozone formation regime dominating in Shanghai. The uneven distribution in space was mainly reflected in the higher FNRSAT and surface O3 concentration in suburban areas. To compensate for the shortcoming of FNRSAT that it can only characterize O3 formation around satellite overpass time, correction of FNRSAT was implemented with hourly surface FNR and O3 data. After correction, the O3 formation regime showed the trend moving towards being VOC-limited in both time and space, and the regime indicated by FNRSAT can better reflect O3 formation for a day. This study can help us better understand HCHO characteristics and O3 formation regimes in Shanghai and also provide a method to improve FNRSAT for characterizing O3 formation in a day, which will be significant for developing O3 prevention and control strategies.

Road Salt Damage to Historical Milestones Indicates Adaptation of Winter Roads to Future Climate Change May Damage Arctic Cultural Heritage

There is no doubt that anthropogenic global warming is accelerating damage to cultural heritage. Adaptation measures are required to reduce the loss of sites, monuments and remains. However, little research has been directed towards understanding potential impacts of climate adaptation measures in other governmental sectors on cultural heritage. We provide a case study demonstrating that winter road salt, used to reduce ice related accidents, damages historical iron milestones. As the climate warms, road salt use will move north into areas where sites have been protected by contiguous winter snow cover. This will expose Artic/sub-Arctic cultural heritage, including Viking graves and Sami sites, to a new anthropogenic source of damage. Research and planning should therefore include the evaluation of secondary impacts when choosing climate adaptation strategies.

Polycyclic aromatic hydrocarbons in the snowpack of Yamal-Nenetz Autonomous region as indicators of anthropogenic source influence

A study of the content and composition of polycyclic aromatic hydrocarbons (PAHs) in the solid fraction of the snowpack is carried out on the territory of the Yamal-Nenetz Autonomous region, the north of Western Siberia. The total content of ten three-six nucleus PAHs was determined in the 51 samples collected at various distances from oil and gas producers and roads, near settlements, and in remote Arctic areas. The total PAH content varies from the lowest 0.3 ng/mg on the Bely Island, increasing to ~ 5 ng/mg in areas of new gas fields, and up to high 15 ng/mg in cities. Characteristic features of PAHs composition under the influence of gas flares emissions in central areas of high technogenic load are identified; they are a total content of up to 144 ng/mg and enrichment with low- molecular weight PAHs. In remote Arctic regions, high-molecular weight 5–6 nucleus PAHs dominate. Profiles of individual PAHs near gas flares, roads and residential sector facilities have been determined. The percentage contribution of the sum of 3, 4 and 5, 6-nucleus PAHs to the total PAH content indicates the gas flaring impact. Ratios of fluorantene to pyrene and benzene(b)fluorantene to benzene(ghi)perylene indicate changes in the snow PAHs composition with a decrease in the gas flaring contribution. The data obtained for the assessment of gas flaring emission impact on the PAHs composition in the snowpack are relevant to polar areas where new fields are being developed.