Aerosol Pollution Research Articles

An Innovative Collaboration-Based Ozone and Aerosol Observation Network in Northeast Asia

Abstract Situated in close proximity to the Korea Peninsula and the Japan Islands, Shandong Province in China (SDP) has emerged as a focal point for global attention due to its significant surface ozone (O3) and aerosol pollution. Despite this attention, there are notable gaps in knowledge across various interconnected research domains, encompassing climate change, atmospheric circulation, anthropogenic emissions, and the chemistry of O3 and aerosols. The impact of frequent heat waves on regional O3 and aerosol pollution remains unclear, while our comprehension of atmospheric circulation dynamics and the chemistry involved with O3 and aerosols is still hampered by substantial limitations. The unique topography and geographical setting of SDP, with its complex interplay of factors like sea–land breezes, mountain–valley winds, and urban heat islands, make it an ideal location for investigating the dynamics of O3 and aerosol chemistry. Moreover, it is essential to explore the effects of transboundary transport on O3 and aerosol pollution and delve into the underlying mechanisms contributing to their combined pollution effects. To bridge these knowledge gaps, the Innovative Collaboration-Based Ozone and Aerosol Observation Network in Northeast Asia has been established through collaborative efforts involving the Bureaus of Ecology and Environment, Meteorology in SDP, and the Chinese Academy of Sciences. This network encompasses various components, including air quality and weather stations, a network of low-cost air quality sensors, monitoring stations focused on atmospheric photochemical smog and aerosol chemical speciation, and vertical measurement systems targeting O3 and its precursor gases (utilizing light detection and ranging, balloon sounding, and drone-based measurements), as well as measurements conducted via vehicles and ships. Additionally, preliminary findings from this comprehensive observational campaign will be shared.

Optimizing concrete rheology to mitigate aerosol pollutants in wet-mix shotcrete processes

Studies focusing on optimizing the pumpability and sprayability of concrete exist; however, research addressing the control of aerosol pollutants during the spraying process is limited. This study investigated the intricate relationships among additive formulations, rheology properties of fresh mixes, and aerosol pollutant emissions using a Box–Behnken design, combined with response surface methodology and gray correlation coefficient analysis. The developed high-accuracy regression model offers valuable insights into the impact of water-reducing agents (WRA), air-entraining agents (AEA), thickening agents (TA), and defoaming agents (DA) on the zeta potential, slump, surface tension of fresh mix concrete, and spread angle during wet-mix shotcrete (WMS), with R2 values of 0.94, 0.95, 0.95, and 0.95, respectively. Additionally, by considering both sprayability and a low spread angle, this approach facilitated the development of an optimal composite incorporating 1.36 % WRA, 1.50 % AEA, 0.20 % TA, and 1.00 % DA, yielding desired properties, including a slump of 200 mm, spread angle of 20°, and aerosol pollutant concentration of 21 mg/m3. This study provides a model to aid the formulation of shotcrete that mitigates aerosol pollutant generation during the WMS process, thereby contributing to the broader objectives of environmental sustainability and workplace safety.

Three-dimensional distribution of aerosols of multiple types at daily scale using TROPOMI spaceborne observations

We present new satellite-based daily observations of the 3D distribution of aerosols from most common types and origins, both over land and ocean, derived from TROpospheric Ozone Monitoring Instrument (TROPOMI) measurements. This is done using the so-called AEROS5P (AEROsol Sentinel 5 Precursor) approach which retrieves vertical profiles of aerosol extinction from passive measurements of high-resolution spectral reflectance in the visible and near infrared for cloud-free conditions. Previous work demonstrated the potential of this approach, but it was initially applicable only to biomass burning aerosols with limited spatial coverage over ocean. The new methodology presented here generalizes the method for the most common aerosol types and improves spatial coverage. We take advantage of an operational aerosol type product derived from Visible Infrared Imaging Radiometer Suite (VIIRS) observations, combined with those from TROPOMI, to choose a priori aerosol set of intensive properties (particle size and refractive index). AEROS5P shows good agreement in aerosol optical depth, when compared to observations from AErosol RObotic NETwork and other widely used satellite measurements. Additionally, the vertical distribution of aerosol plumes of different types derived from AEROS5P agrees well with lidar coincident observations from the Advanced Topographic Laser Altimeter System spaceborne sensor and ground-based measurements. We utilize AEROS5P to analyze the three-dimensional distribution of aerosols for four different scenarios. It traces the three-dimensional pathways of smoke from Canadian wildfires reaching the Eastern USA in July 2023, desert dust from the Namibian deserts over the southeast Atlantic Ocean confined near the surface during the same month, fine aerosol pollution over Western Europe during June 2019, and an extreme dust event mixed with fine aerosol pollution over Northern China in March 2021. These observations provide valuable insights into aerosol transport patterns, surface-level air quality impacts, and can potentially be used to assess the radiative effects at various atmospheric layers.

ОЦІНКА ПОТОЧНОГО СТАНУ РАДІАЦІЙНОГО ЗАБРУДНЕННЯ ТЕРИТОРІЇ МАЙДАНЧИКУ УРАНОВОЇ СПАДЩИНИ КОЛИШНЬОГО ВО «ПХЗ»

The article summarizes the results of long-term radioecological monitoring of the environment radioactive state within the former 'Prydniprovsk chemical plant' and adjacent territories at the preparatory stage life cycle of uranium legacy site. Data analysis have been determined the background activity levels of natural radionuclides (in particular 238U, 226Ra, 230Th, 210Pb, 210Po) in soils, underground and surface waters, air (fall density and volume activity), exhalation of 222Rn from the soil surface and its volume activity. The results of the determined dynamics and trends in the formation of pollution of environmental elements, which form the main factors of exposure of workers and the population, are presented. Areas with elevated dose rate (≥0.5 μSv·h-1) occupy more than 30% of the entire legacy site territory. In the soil activity may be 10 to 1000 times higher than background (30-50 Bq·kg-1) and can exceed 1000 times the exemption level. In aerosols 238U and 226Ra activitis exceeding the background (0.1 µBq·m-2·s-1, 11.5 µBq·m3) by 100-200 times only during periods of earthworks, under normal conditions they are up to 1.5-2.0 times. The monthly average activity 222Rn in the air of open space are 4-5 times higher of the background (median 200±68 Bq∙m-3), in some areas they can exceed by up to 50 times. In the buildings premises on the site 222Rn can exceed the reference level (250 Bq∙m-3) by 1-5 times, and in individual basements by up to 100 times. The data analysis proves that main ways of exposure of workers are external gamma radiation, the inhalation exposure routes from aerosol pollution and the spread of OA 222Rn in the air can be significant only for workers work at the legacy site and do not pose a threat to the city's population. Radiation assessment contamination of underground and surface water showed in present conditions aquatic pathways cannot form any significant contributions to the radiation exposure dose of the public. The obtained results and data analysis of monitoring observations were used to substantiate the measures of the remediation strategy legacy site.

Влияние интенсивных атмосферных осадков на загрязнение воздуха города Владивостока

Concentrations of the main substances polluting the atmosphere over Vladivostok (sulfur dioxide, carbon monoxide, nitrogen dioxide, and PM2.5, PM10 particles) before, during, and after stormwater solid and liquid precipitation on December 21–23, 2022 and June 8–9, 2023, respectively, are considered. The development of synoptic processes that caused this precipitation, air particle trajectories (using the HYSPLIT model), and the variation pattern of pollutant concentrations recorded using the GMAO satellite monitoring during these periods are analyzed. It is shown that heavy rainfall significantly cleanses the atmosphere from aerosol pollution, and during snowfalls, carbon monoxide is better washed out of the atmosphere, and PM10 and PM2.5 particles almost completely fall on the underlying surface.

Modeling Analysis of Nocturnal Nitrate Formation Pathways during Co-Occurrence of Ozone and PM2.5 Pollution in North China Plain

The rapid formation of secondary nitrate (NO3−) contributes significantly to the nocturnal increase of PM2.5 and has been shown to be a critical factor for aerosol pollution in the North China Plain (NCP) region in summer. To explore the nocturnal NO3− formation pathways and the influence of ozone (O3) on NO3− production, the WRF-CMAQ model was utilized to simulate O3 and PM2.5 co-pollution events in the NCP region. The simulation results demonstrated that heterogeneous hydrolysis of dinitrogen pentoxide (N2O5) accounts for 60% to 67% of NO3− production at night (22:00 to 05:00) and is the main source of nocturnal NO3−. O3 enhances the formation of NO3 radicals, thereby further promoting nocturnal N2O5 production. In the evening (20:00 to 21:00), O3 sustains the formation of hydroxyl (OH) radicals, resulting in the reaction between OH radicals and nitrogen dioxide (NO2), which accounts for 48% to 64% of NO3− formation. Our results suggest that effective control of O3 pollution in NCP can also reduce NO3− formation at night.

Aerosol type classification and its temporal distribution in Kanpur using ground-based remote sensing

Based on AERONET version 3 level 2 inversion products, we classify aerosol types and investigate their temporal distribution in the atmosphere using particle linear depolarization ratio (PLDR) and single scattering albedo (SSA) at the wavelength of 1020 nm over Kanpur. It is for the first time over the North Indian region the work has been emphasized. The remarkable findings over Kanpur station indicate that SSA and coarse-mode particles in the atmosphere increased with increasing PLDR at 440, 675, 870, and 1020 nm wavelengths. It is observed in the 2-dimensional histogram that the rate of occurrence of aerosols is high when the fine mode fraction (FMF) is high and the dust ratio (Rd) is low. The atmosphere of Kanpur is partially influenced by dust-dominated mixture (DDM), pollution-dominated mixture (PDM), and pure dust (PD) with 53% whereas, the rest of the dust-free pollution aerosols are 47%. The annual mean occurrence rate for different aerosol types is 5% for Strongly Absorbing (SA), 20% for Moderately Absorbing (MA), 19% for Weakly Absorbing (WA), 3% for Non-Absorbing (NA), 27% for DDM, 22% for PDM, and 4% for PD, ranging from January 2001 to January 2022. There is a variation in the distribution of various types of pollution particles, which is influenced by the changing seasons. The rate of occurrence of dust-free pollution aerosols is 47%, mostly observed throughout the post-monsoon and winter seasons. The PLDR values in the atmosphere of Kanpur are almost balanced equally because it is affected by both (dust and dust-free) pollution aerosols and the changes can be seen due to the frequent occurrence of dust storms and anthropogenic activities.

Spatiotemporal Variation in Absorption Aerosol Optical Depth over China

Absorbing aerosols can absorb solar radiation, affect the atmospheric radiation balance, and further have a profound influence on the global and regional climates. The absorption aerosol optical depth (AAOD) as well as the absorption Angstrom exponent (AAE) across China over 2005–2018 were systematically studied through the Ozone Monitoring Instrument (OMI) dataset. The monthly AAOD samples from the OMI generally showed a good correlation (~0.55) compared to the monthly data from AERONET at four typical sites (North: Xianghe, East: Taihu, South: Hongkong Polytechnic Univ; Northwest: Sacol) across China. The ensemble annual average of the OMI AAOD at 388 and 500 nm is 0.046 and 0.022, with minor changes during 2005–2015, and a relatively fast increase after that. The winter and spring seasons depict the maximum mean AAODs, followed by autumn, whereas summer shows minimum levels. On the contrary, the high AAE values appear in summer and low values in winter. The order of the annual average AAOD500 from 2005 to 2018 is the Tarim Basin (TB, 0.041) > the Yellow River Basin (YRB, 0.023) > Beijing and Tianjin (BT, 0.026) > the Sichuan Basin (SB, 0.023) > Nanjing and Shanghai (NS, 0.021) > the Pearl River Delta (PRD, 0.017), whereas the AAE388–500 exhibits the opposite trend except for the TB (3.058). From 2005 to 2018, the AAOD rises by nearly 1.5–2.0 fold in the six typical regions, implying a severe situation of dust and/or BC aerosol pollution in the last several years. The monthly mean AAOD388 over the TB, the SB, the YRB, BT, the PRD, and NS is estimated to be smallest at 0.072, 0.024, 0.026, and 0.027 in July, 0.024 in June, and 0.025 in September, respectively, whilst largest in January for NS, the YRB and BT, April for the TB, February for the SB, and March for the PRD with 0.055, 0.077 and 0.067, 0.123, and 0.073 and 0.075, respectively. The monthly averaged AAOD500 in each region is consistently about half of the AAOD388. The highest AAE appears in June while the lowest values are in December and January, and the daily AAE values in episode days slightly decrease as compared to non-episode days. Our study indicates that northwestern China plays an important role in the overall AAOD as a result of dust aerosols stemming from desert areas. Moreover, the meteorological conditions in winter and early spring are associated with more energy consumption conducive to the accumulation of high black carbon (BC) aerosol pollution, causing high alert levels of AAOD from November to the following March.

Observation and Classification of Low-Altitude Haze Aerosols Using Fluorescence–Raman–Mie Polarization Lidar in Beijing during Spring 2024

Haze aerosols have a profound impact on air quality and pose serious health risks to the public. Due to its geographical location, Beijing experienced haze events in the spring of 2024. Lidar is an active remote sensing technology with a high spatiotemporal resolution and the ability to classify aerosols, and it is essential for effective haze monitoring. This study utilizes fluorescence–Raman–Mie polarization lidar with an emission wavelength of 355 nm, employing the δp-Gf method based on the particle depolarization ratio at 355 nm (δp355) and the fluorescence capacity (Gf), and combines meteorological data and backward-trajectory analysis to observe and classify low-altitude haze aerosols in Beijing during the spring of 2024. Notably, a mining dust event with strong fluorescence backscatter was detected. The haze aerosols were categorized into three types: pollution aerosols, desert dust, and mining dust. Their optical properties were summarized and compared. Desert dust showed a particle depolarization ratio range of 0.23–0.39 and a fluorescence capacity range from 0.18 × 10−4 to 0.63 × 10−4. Pollution aerosols had a larger fluorescence capacity but a lower depolarization ratio compared to desert dust, with a fluorescence capacity ranging from 0.55 × 10−4 to 1.10 × 10−4 and a depolarization ratio ranging from 0.10 to 0.17. Mining dust shared similar depolarization characteristics with desert dust but had a larger fluorescence capacity, ranging from 0.71 × 10−4 to 1.23 × 10−4, with a depolarization ratio range of 0.30–0.39. This study validates the effectiveness of the δp355-Gf method in classifying low-altitude haze aerosols in Beijing. Additionally, it offers a new perspective for more detailed dust classification using lidar. Furthermore, utilizing the δp355-Gf classification method and the δp355-Gf distributions of three typical aerosol samples, we developed a set of equations for the analysis of mixed aerosols. This method facilitates the separation and fraction analysis of aerosol components under various mixing scenarios. It enables the characterization of variations in the three types of haze aerosols at different altitudes and times, offering valuable insights into the interactions between desert dust, mining dust, and pollution aerosols in Beijing.

Development of the full Lagrangian approach for modeling dilute dispersed media flows (a review)

Continuum models of media with zero pressure are widely used in various branches of physics and mechanics, including studies of a dilute dispersed phase in multiphase flows. In zero-pressure media, the particle trajectories may intersect, “folds” and “puckers” of the phase volume may arise, and “caustics” (the envelopes of particle trajectories) may appear, near which the density of the medium sharply increases. In recent decades, the phenomena of clustering and aerodynamic focusing of inertial admixture in gas and liquid flows have attracted increasing attention of researchers. This is due to the importance of taking into account the inhomogeneities in the impurity concentration when describing the transport of aerosol pollutants in the environment, the mechanisms of droplet growth in rain clouds, scattering of radiation by dispersed inclusions, initiation of detonation in two-phase mixtures, as well as when solving problems of two-phase aerodynamics, interpretation of measurements obtained by LDV or PIV methods, and in many other applications. These problems gave an impetus to a significant increase in the number of publications devoted to the processes of accumulation and clustering of inertial particles in gas and liquid flows. Within the framework of classical two-fluid models and standard Eulerian approaches assuming single-valuedness of continuum parameters of the media, it turns out impossible to describe zones of multi-valued velocity fields and density singularities in flows with crossing particle trajectories. One of the alternatives is the full Lagrangian approach proposed by the author earlier. In recent years, this approach has been further developed in combination with averaged Eulerian and Lagrangian (vortex-blob method) methods for describing the dynamics of the carrier phase. Such combined approaches made it possible to study the structure of local zones of accumulation of inertial particles in vortex, transient, and turbulent flows. This article describes the basic ideas of the full Lagrangian approach, provides examples of the most significant results which illustrate the unique capabilities of the method, and gives an overview of the main directions of further development of the method as applied to transient, vortex, and turbulent flows of “gas-particle” media. Some of the ideas discussed and the results presented below are of a more general interest, since they are also applicable to other models of zero-pressure media.

Quantifying the diurnal variation in atmospheric NO2 from Geostationary Environment Monitoring Spectrometer (GEMS) observations

Abstract. The Geostationary Environment Monitoring Spectrometer (GEMS) over Asia is the first geostationary Earth orbit instrument in the virtual constellation of sensors for atmospheric chemistry and composition air quality research and applications. For the first time, the hourly observations enable studies of diurnal variation in several important trace gas and aerosol pollutants including nitrogen dioxide (NO2), which is the focus of this work. NO2 is a regulated pollutant and an indicator of anthropogenic emissions in addition to being involved in tropospheric ozone chemistry and particulate matter formation. We present new quantitative measures of NO2 tropospheric column diurnal variation which can be greater than 50 % of the column amount, especially in polluted environments. The NO2 distribution is seen to change hourly and can be quite different from what would be seen by a once-a-day low-Earth-orbit satellite observation. We use GEMS data in combination with TROPOspheric Monitoring Instrument (TROPOMI) satellite and Pandora ground-based remote sensing measurements and Multi-Scale Infrastructure for Chemistry and Aerosols (Version 0, MUSICAv0) 3D chemical transport model analysis to examine the NO2 diurnal variation in January and June 2023 over Northeast Asia and Seoul, South Korea, study regions to distinguish the different emissions, chemistry, and meteorological processes that drive the variation. Understanding the relative importance of these processes will be key to including pollutant diurnal variation in models aimed at determining true pollutant exposure levels for air quality studies. The work presented here also provides a path for investigating similar NO2 diurnal cycles in the new Earth Venture Instrument-1 Tropospheric Emissions: Monitoring Pollution (TEMPO) data over North America, and later over Europe with Sentinel-4.

Vertical Variability of Aerosol Pollution in St. Petersburg According to Long-term Lidar Observations

Processing of data obtained using lidar technologies was carried out to identify the vertical variability of the distribution of aerosols in the atmospheric column by month. The results of 227 lidar measurements from 2014 to 2023 were processed in total. It has been established that the concentration and height of compacted aerosol layers begin to increase in spring time, reaches a maximum in July, and from October there is a visible decline in aerosol concentrations in the atmospheric air. It has been established that in the warm season the height of compacted aerosol layers reaches 1200–1800 m, while in the cold season it reaches only heights of 600–1100 m. It was concluded that fine aerosol predominates over the city, based on the calculated Angstrom parameter in the range from 1.95 to 2.91.

Seasonal variation of water-soluble inorganic ions and carbonaceous components of PM2.5 and PM1 in industrial and residential areas of Suizhou, China

Seasonal variations of fine particulate matter (PM) and its chemical components in Suizhou are investigated by collecting PM2.5 and PM1 samples from industrial and residential areas between March 2017 and February 2018. The findings reveal more severe PM pollution in industrial areas compared to residential areas. Concentrations and percentages of water-soluble inorganic ions (WSII) in PM are higher in spring and winter. Notably, the high levels of SO42− and NO3− in PM1-2.5 indicate that secondary transformation of SO2 and NOx significantly contribute to the rapid increase in PM1-2.5. The conversion of NO2 to NO3− is a key factor in the winter increase of mass concentrations of PM2.5 [ρ(PM2.5)], while photochemical reactions involving NO2 drive the summer increase of ρ(PM2.5). Organic carbon (OC) and elemental carbon (EC) are mainly distributed in PM1, with OC peaking in winter. Chemical fractionation of PM reveals that carbonaceous components have a greater impact on PM1 concentration than WSII, whereas WSII more significantly affects ρ(PM2.5) than carbonaceous components. The OC to EC ratio in industrial areas (2.5 ± 1.4) and residential areas (1.9 ± 0.8) suggests more prominent secondary aerosol pollution in industrial areas. Significant correlations between secondary organic carbon (SOC), SOC conversion rate (ηSOC), and concentrations of O3-8h and NO2 in Suizhou further indicate that O3 and NO2 levels in the atmosphere influence the generation of SOC and ηSOC.

Investigation on special reactivity of sulfite as an electron acceptor for the attenuated Fenton reaction and the abatement mechanism

Sulfur(IV) as a ubiquitous substance in the atmosphere and water bodies can be deliberately involved in different redox reactions based on the known ability to donate electrons, but the inhibition effect on the advanced oxidation processes (AOPs) especially the Fenton reaction, which played a vital role in aerosol aging and pollution treatment, still stayed fuzzy. In this work, it was first found that sulfite had an unexpected reactivity to accept electrons from Fe(II) monitored by the chemiluminescence (CL) method to reduce Fe(II) seriously. Dynamics calculation, UV–vis absorption, HPLC, and CL analysis indicated that sulfite anions can be transferred into SO2·- or dimer S2O42- through reacting with Fe(II). The direct consumption of Fe(II) in Fenton reaction only happened by sulfite among other inorganic anions during degrading different organic pollution, and the produced S2O42- showed an overpowering inhibitory ability on hydroxyl radical especially at pH 5.3, both resulting in a strong inhibition effect on the Fenton reaction. In contrast at pH 3.1, the fast depletion of sulfite by H2O2 and decomposition of S2O42- fell off the inhibition effect. Furthermore, abatement experiments showed that the effect of sulfite could be circumvented by using a non-iron-based oxidation system with other metal ions, additionally clarifying the reaction of Fe(II)-sulfite played the primary role in the inhibition. Significantly, this inhibition effect of sulfite on the Fenton reaction was demonstrated to take place both in the natural wastewater and degrading two acids from biomass burning in the atmosphere, identifying the attenuated Fenton reaction in the presence of sulfur(IV) in the environment.

Substantial contribution of transported emissions to organic aerosol in Beijing

Haze in Beijing is linked to atmospherically formed secondary organic aerosol, which has been shown to be particularly harmful to human health. However, the sources and formation pathways of these secondary aerosols remain largely unknown, hindering effective pollution mitigation. Here we have quantified the sources of organic aerosol via direct near-molecular observations in central Beijing. In winter, organic aerosol pollution arises mainly from fresh solid-fuel emissions and secondary organic aerosols originating from both solid-fuel combustion and aqueous processes, probably involving multiphase chemistry with aromatic compounds. The most severe haze is linked to secondary organic aerosols originating from solid-fuel combustion, transported from the Beijing–Tianjing–Hebei Plain and rural mountainous areas west of Beijing. In summer, the increased fraction of secondary organic aerosol is dominated by aromatic emissions from the Xi’an–Shanghai–Beijing region, while the contribution of biogenic emissions remains relatively small. Overall, we identify the main sources of secondary organic aerosol affecting Beijing, which clearly extend beyond the local emissions in Beijing. Our results suggest that targeting key organic precursor emission sectors regionally may be needed to effectively mitigate organic aerosol pollution.

Compositions and sources of fluorescent water-soluble and water-insoluble organic aerosols

Brown carbon (BrC), the light-absorbing component of organic aerosols, plays a significant role in climate change and atmospheric photochemistry. However, the water-insoluble fractions of BrC have not been extensively studied, limiting the assessment of the overall climate effects of BrC. In this study, water-soluble and -insoluble organic carbon (i.e., WSOC and WIOC) in wintertime aerosols in Hefei were subsequently fractionated, and their fluorescence properties were comparatively investigated with the excitation–emission matrix method. WIOC contributing 57.1 % was the major component of organic carbon. WSOC with the largest contribution from humic-like regions exhibited a redshift compared to WIOC. Three humic-like substances (HULIS) with different oxidation degrees and one protein-like substances (PRLIS) were identified as the major fluorescent components by the parallel factor analysis. WSOC had more highly oxygenated HULIS, whereas low-oxygenated HULIS dominated WIOC. Nighttime WIOC contained more less-oxygenated species. The positive matrix factorization analysis suggested that biomass burning (43 %) was the largest source of both fluorescent WSOC and WIOC. Coal combustion contributed much more to fluorescent WIOC (40 %), whereas secondary formation contributed more to fluorescent WSOC (12 %). During aerosol pollution episodes, the increase in fluorescence efficiency was much greater for WIOC (25 %) than for WSOC (12 %), and WSOC and WIOC experienced a redshift and blueshift in emission wavelength, respectively. WSOC had more highly oxygenated HULIS, while WIOC had more less-oxygenated HULIS in aerosol episodes than the non-episodic periods. In addition, aerosol pollution was accompanied by the increased contributions of biomass burning and coal combustion to both fluorescent WSOC and WIOC, while the decreased relative contribution of secondary formation to fluorescent WSOC. Our findings highlighted the different fluorescence properties, compositions and sources of fluorescent WSOC and WIOC, providing a comprehensive view of BrC aerosols.

Vulnerability assessment of aerosol and climate variability for rice and maize yield using EO datasets for sustainable agriculture over India.

Human-generated aerosol pollution gradually modifies the atmospheric chemical and physical attributes, resulting in significant changes in weather patterns and detrimental effects on agricultural yields. The current study assesses the loss in agricultural productivity due to weather and anthropogenic aerosol variations for rice and maize crops through the analysis of time series data of India spanning from 1998 to 2019. The average values of meteorological variables like maximum temperature (TMAX), minimum temperature (TMIN), rainfall, and relative humidity, as well as aerosol optical depth (AOD), have also shown an increasing tendency, while the average values of soil moisture and fraction of absorbed photosynthetically active radiation (FAPAR) have followed a decreasing trend over that period. This study's primary finding is that unusual variations in weather variables like maximum and minimum temperature, rainfall, relative humidity, soil moisture, and FAPAR resulted in a reduction in rice and maize yield of approximately (2.55%, 2.92%, 2.778%, 4.84%, 2.90%, and 2.82%) and (5.12%, 6.57%, 6.93%, 6.54%, 4.97%, and 5.84%), respectively. However, the increase in aerosol pollution is also responsible for the reduction of rice and maize yield by 7.9% and 8.8%, respectively. In summary, the study presents definitive proof of the detrimental effect of weather, FAPAR, and AOD variability on the yield of rice and maize in India during the study period. Meanwhile, a time series analysis of rice and maize yields revealed an increasing trend, with rates of 0.888 million tons/year and 0.561 million tons/year, respectively, due to the adoption of increasingly advanced agricultural techniques, the best fertilizer and irrigation, climate-resilient varieties, and other factors. Looking ahead, the ongoing challenge is to devise effective long-term strategies to combat air pollution caused by aerosols and to address its adverse effects on agricultural production and food security.

Distribution Characteristics and Source Analysis of Carbonaceous Aerosols Before and After the Spring Festival in the Guanzhong Plain

The spatio-temporal variation characteristics and potential sources of carbonaceous aerosols in the Guanzhong Plain during the Spring Festival in 2023 were analyzed using inverse distance weighting spatial interpolation （IDW）, secondary organic carbon （SOC） estimation, and potential source contribution factor analysis （PSCF）, with the OC and EC in the PM2.5 of five cities： Xi'an, Baoji, Xianyang, Weinan, and Tongchuan as the research objects. The results showed that in terms of time distribution, ρ（OC） was as follows： after the Spring Festival [（18.6 ±11.0） μg·m-3] &gt; during the Spring Festival [（16.2 ±15.1） μg·m-3] &gt; before the Spring Festival [（10.0 ±8.3） μg·m-3], and ρ（EC） was as follows： after the Spring Festival [（2.2 ±1.2） μg·m-3] &gt; during the Spring Festival [（1.7 ±1.5） μg·m-3] &gt; before the Spring Festival [（1.4 ±1.1） μg·m-3], which indicated that OC and EC concentrations were the most severe after the Spring Festival. In terms of spatial distribution, ρ（OC） was as follows： Xianyang [（21.4 ±17.3） μg·m-3] &gt; Baoji [（15.8 ±12.8） μg·m-3] &gt; Xi'an [（13.6 ±11.3） μg·m-3] &gt; Weinan [（11.6 ±9.1） μg·m-3] &gt; Tongchuan [（10.0 ±8.3） μg·m-3], and ρ（EC） was as follows： Xianyang [（2.1 ±1.4） μg·m-3] &gt; Weinan [（1.8 ±1.4） μg·m-3] &gt; Xi'an [（1.8 ±1.2） μg·m-3] &gt; Tongchuan [（1.6 ±1.4） μg·m-3] &gt; Baoji [（1.2 ±0.9） μg·m-3]. Overall, Xianyang had the most severe PM2.5 and carbon aerosol pollution, whereas Tongchuan had the least pollution. IDW results showed that the high-value center of OC and EC concentration [ρ（OC） &gt; 27.3 μg·m-3, ρ（EC） &gt; 2.9 μg·m-3] was in the middle of the plain, the low-value center of OC and EC concentration [ρ（OC） <7.0 μg·m-3, ρ（EC） < 1.0 μg·m-3] was in the northern plain, and the distribution of OC was higher in the west and lower in the east, whereas the distribution of EC was higher in the east and lower in the west. The proportion of SOC in OC was as follows： after the Spring Festival （51.7%） &gt; during the Spring Festival （41.1%） &gt; before the Spring Festival （36.8%）. The SOC/OC values of each city and the contribution rate of SOC of each city to the Guanzhong Plain indicated that Tongchuan, Baoji, and Xianyang were greatly affected by the secondary conversion of organic carbon. The correlation of OC and EC before, during, and after the Spring Festival （r = 0.85, r = 0.98, and r = 0.94, respectively） indicated a high degree of homology between them. Carbonaceous aerosols had a certain correlation with humidity and wind speed before and during the Spring Festival but had a weak correlation with meteorological factors after the Spring Festival. Carbonaceous aerosols generally were strongly correlated with CO and NO2, and the correlation was strongest after the Spring Festival, whereas the correlation with SO2 was strongest during the Spring Festival. The potential source areas of carbonaceous aerosols in the five cities were mainly concentrated in the local and surrounding areas of southern Gansu, northern Shaanxi, and southern Shaanxi. They were also affected by long-distance transportation from the northwest before the Spring Festival.

Co‐Benefits of Mitigating Aerosol Pollution to Future Solar and Wind Energy in China Toward Carbon Neutrality

AbstractThe climate commitment to achieving carbon neutrality before 2060 in China has been announced recently. In the context of pursuing carbon neutrality, sharing similar sources as greenhouse gases, aerosol particle and precursor emissions are projected to substantially decrease in China, which can potentially have a great impact on climate. Here, we investigate the effects of future aerosol reductions, because of achieving carbon neutrality, on solar and wind energy in China by using an earth system model. We show that significant reductions in aerosol emissions, particularly in eastern China, lead to increases in the surface downwelling shortwave radiation, surface air temperature and wind speed, which can further enhance the potential of solar and wind energy production. The findings underline that the pursuit of carbon neutrality can yield co‐benefits of not only mitigating climate change and air pollution but also fortifying the stability of renewable energy sources.

In vitro evaluation of the toxicological effects of cooking oil fumes using a self-designed microfluidic chip

Cooking oil fumes (COFs) are widely acknowledged as substantial contributors to indoor air pollution, having detrimental effects on human health. Despite the existence of commercialized in vitro aerosol exposure platforms, assessment risks of aerosol pollutants are primarily evaluated based on multiwell plate experiments by trapping and redissolving aerosols to conduct comprehensive in vitro immersion exposure manner. Therefore, an innovative real-time exposure system for COF aerosol was constructed, featuring a self-designed microfluidic chip as its focal component. The chip was used to assess toxicological effects of in vitro exposure to COF aerosol on cells cultured at the gas–liquid interface. Meanwhile, we used transcriptomics to analyze genes that exhibited differential expression in cells induced by COF aerosol. The findings indicated that the MAPK signaling pathway, known for its involvement in inflammatory response and oxidative stress, played a crucial role in the biological effects induced by COF aerosol. Biomarkers associated with inflammatory response and oxidative stress exhibited corresponding alterations. Furthermore, the concentration of COF aerosol exposure and post-exposure duration exert decisive effects on these biomarkers. Thus, the study suggests that COF can induce oxidative stress and inflammatory response in BEAS-2B cells, potentially exerting a discernible impact on human health.