This study conducts a comprehensive estimation of aerosol optical depth (AOD) trend and a classification of types of aerosols over the Eastern Mediterranean (EM) region using the Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2) AOD and Angstrom exponent (AE) during 1980–2018 and MODerate resolution Imaging Spectroradiometer (MODIS) Collection 6.1/Terra and Aqua products

Polyurethane foam (PUF) passive air samplers (PAS) are widely used for measurements of persistent organic pollutants (POPs) and other semi-volatile organic compounds (SVOCs) in large-scale monitoring networks as well as in case studies around the globe. Calibration of PUF-PAS is performed by field-based calibration studies or passive sampler uptake models, but both these are typically performed and/or

Surface snow along a 1250-km transect from the coast to the East Antarctic ice sheet summit Dome Argus are used to investigate factors influencing spatial variability of perchlorate (ClO4−) production and deposition, and to explore contributions from tropospheric and stratospheric sources to ClO4− in Antarctic snow. The average ClO4− concentration of 104.3 ± 33.3 ng kg−1 is in the range of previously

Glyoxal (GLY) and methylglyoxal (MGLY), as tracers of oxidation of volatile organic compounds (VOCs), play an important role in atmospheric chemistry. In this work, the concentrations of these two aldehydes were simultaneously measured online at a regional site in Jiangsu Province (China) during the 2018 EXPLORE-YRD campaign. The maximum measured concentration of GLY and MGLY was 0.47 and 6.68 ppb

Air pollution in China has reached unprecedented levels due to rapid economic and industrial development. More than 90% of Chinese population experience higher health risks attributable to ambient fine particulate matter (PM2.5) exposure. Although evidence suggests that particle size may be an effect modifier on PM2.5-related health risks, few studies have explored this due to lack of size-resolved

In the Northwest U.S. elevated measurements of PM2.5 from anthropogenic sources occur most often in winter. Major contributors to winter PM2.5 are direct primary emissions of wood smoke from residential wood combustion, primary emissions from motor vehicles, gaseous NOx emissions leading to particulate nitrate, and primary and secondary sources of particulate sulfate. A number of communities in the

In 2015, 2016, the US Army conducted nine large-scale chlorine releases at the Dugway Proving Ground in Utah, known as the Jack Rabbit II trials. The purpose of these experiments was to improve our understanding of pressure-liquefied chlorine releases and atmospheric dispersion, and to provide useful practical knowledge for emergency responders. Data from three of the Jack Rabbit II trials (Trials

Biomass burning (BB) is one of the major sources of atmospheric aerosols. These aerosols cause global and regional issues such as adverse effects on human health, as well as contributing to climate change. Refractory black carbon (rBC) is a major chemical component emitted from BB. Recent studies indicate that the mass spectra distribution of carbon cluster ions (Cn+) in rBC reflects burning materials

The Fengyun-4A (FY-4A) meteorological satellite, a next-generation geostationary meteorological satellite, was launched on December 11, 2016. For instance, the Advanced Geosynchronous Radiation Imager (AGRI) aboard FY-4A (AGRI/FY-4A) takes full-disk images at a 15-min interval in 14 spectral bands with the 0.5–4-km resolution. Here we developed data assimilation system based on the Gridpoint Statistical

Previous research has proposed use of satellite-retrieved aerosol optical depth (AOD) to generate geospatial assessments of near-surface PM2.5 mass concentrations and potentially to provide air quality forecasts. Spatiotemporal variability in PM2.5–AOD relationships over the eastern United States of America are analyzed using surface observations, satellite data, reanalysis data, and WRF-Chem simulations

This work assessed the effects of biodiesel on carbonyl emissions from diesel trucks. Biodiesel converted from waste cooking oil was employed and mixed with commercial fossil diesel to produce four blends: B0 (pure conventional diesel fuel), B5 (5% v/v biodiesel), B20 (20% v/v biodiesel) and B100 (pure biodiesel). Four diesel trucks were tested under real-world conditions using a portable emissions

The particle number concentrations, size distributions, and new particle formation (NPF) events were investigated in the South Asian outflow over South-eastern Arabian Sea (SEAS), northern (NIO) and the equatorial Indian Ocean (EIO) during the winter of 2018 based on the extensive measurements of particle number size distributions in size range 10–414 nm in the marine atmospheric boundary layer (MABL)

Quantification of the dispersion rate and extent of gaseous substances leaked into the atmosphere is important for public safety and risk management as industrial facilities are being situated ever closer to populated areas. The complex interaction between atmospheric conditions and built environments makes urban dispersion prediction challenging in nature. Computational fluid dynamics (CFD) has emerged

Volcanic eruptions emit a vast amount of sulfur dioxide (SO2) and ash into the air, often imposing substantial impacts on air quality and the ecosystem. Quantifying its impacts, however, is difficult due to the uncertainties in estimating the strength and variations of volcanic emissions. Here we developed and evaluated a new approach to combine satellite SO2 detection and chemical transport modeling

A variety of legislative actions for air quality improvement have been conducted in China since 2013, and the emission control measures have achieved remarkable reduction in severe haze frequency. The composition of the fine particles may change along with the improved air quality, and thus may induce distinct environmental and climate effects in future. In this study, a very recent long-term dataset

Dust aerosols from the desert areas of China can be lifted to the upper troposphere and transported eastward by the westerly, affecting regional and local air pollution process. In this paper, we analyzed the long-range transport of dust and its impact on the haze-fog process that occurred in Tianjin from 23 November to 5 December 2018. Satellite and ERA5 reanalysis data revealed that dust from northwestern

The distribution and transportation characteristics of dust aerosol over the Tibetan Plateau (TP) and Taklimakan Desert (TD) were analyzed during 1980–2017 using MERRA-2 (second Modern-Era Retrospective analysis for Research and Applications) and CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) products. The aerosol optical depth (AOD) of MERRA-2 were compared with those

Secondary organic aerosol (SOA) plays an important role in global climate change and air quality, and SOA tracers most directly characterize the sources and formation mechanisms of SOA. Four seasons of observation of SOA tracers was carried out in a coastal city of southeastern China. Fourteen PM2.5-bound SOA tracers, including isoprene (SOAI), α/β-pinene (SOAM), β-caryophyllene (SOAC), and toluene

The rate coefficient for the gas phase reaction of the OH radical with 1,2-propylene oxide (PPO) has been measured at 298 K using a relative rate method, employing Gas Chromatography (GC) technique, using ethane and 1,2-dichloroethane as reference compounds. Temperature dependence of the above reaction is also studied using an absolute rate method, employing Laser Photolysis-Laser Induced Fluorescence

The analysis of three extreme African dust outbreaks over the Iberian Peninsula (IP) shows that a double Rossby wave breaking (RWB) process in the polar jet (PJ) creates the conditions for dust storm formation over subtropical deserts in North Africa and the restructuring of upper-level air flows critical for the dust transport poleward after ablation. Two consecutive anticyclonic RWBs initiate over

This work aims to highlight the importance of refining the calculation of exposure to primary pollutants in dense urban areas, by taking into account both pollutant concentration heterogeneity at the street scale, and individual mobility during the day. To address this issue, we have set up an urban modeling chain based on the OLYMPUS and CHIMERE models, and offering innovative statistical work on

Understanding the local sources of atmospheric formaldehyde (HCHO) is a key step in accurately determining the inversion of biogenic volatile organic compounds (BVOCs). This study aims to clarify the main sources and emission patterns of local total HCHO column densities over Ethiopia and Kenya. Between 2005 and 2015, the total monthly HCHO varied from 3.7 × 1015 molecules/cm2 to 7.7 × 1015 molecules/cm2

Indoor air quality is affected by both emissions of Volatile Organic Compounds (VOC) from materials and ventilation. The purpose of this paper is to provide a multi-scale analysis of the impact of ventilation on VOC emissions to highlight the individual behaviours of VOCs emitted from a wood particleboard. Emissions were studied in an experimental chamber by (i) assessing the effect of ventilation

Nitroaromatic compounds (NACs) were believed as one of the major light absorption components in brown carbon (BrC) and important fractions of organic aerosols. To understand the chemical compositions and light absorption of NACs in the highly polluted atmospheres, a field campaign was conducted in the winter of urban Beijing. Ambient PM2.5 samples were collected and a total of 12 NACs were identified

Heterogeneous aging of organic aerosols can significantly alter their physicochemical properties and thus their impacts on the radiative balance of the earth system. In this study, kinetics and mechanisms of heterogeneous reactions between suspended squalane particles and hydroxyl (OH) radicals were investigated using a self-made photooxidation flow tube and a high-resolution long time-of-flight chemical

We investigated the contribution of road traffic and shipping related emissions of NO2 and PM2.5 to total air quality and annual mean population exposure in Hamburg 2012). For this purpose, we compiled a detailed emission inventory following SNAP categories focusing on the detailed representations of road traffic and shipping emissions. The emission inventory was applied to a global-to-local Chemistry

In order to clarify the deposition amounts and processes of bioavailable nitrogen species including organic forms on forests, a simultaneous observation of rainfall, throughfall, stemflow, aerosols, and their precursor gases was conducted for a two-year period at a forested site on the northern foot of Mt. Fuji in Japan. About 80–90% of the rainfall waters reached the forest floor via the throughfall

Six World Meteorological Organization (WMO)/Global Atmosphere Watch (GAW) stations are located at background sites in China, which constitute a network for monitoring surface ozone, including its long-term temporal variation. In this study, we evaluated the seasonal variation in surface ozone simulated by the ECHAM/MESSy Atmospheric Chemistry (EMAC) general circulation model with the measurements made

The incorporation of spatial and temporal correlations can significantly improve the accuracy of PM2.5 concentration prediction models. However, the dynamic spatial panel model which explicitly deals with these two correlations remains absent from current approaches to out-of-sample concentration prediction. An issue is that the prediction of daily concentrations for grid points across a vast area

Conducting high-resolution air quality analysis by applying microscale dispersion models at the regional scale poses a formidable computing challenge, because a huge number of receptors and the extensive network of roadway links (emission sources) must be processed. As a way to minimize computation cost without undermining estimation precision, this study proposes an innovative link screening methodology

Nitrosamines and nitramines are groups of chemical compounds containing nitroso (N-NO) and nitro (N-NO2) functional groups, respectively. They exert detrimental effects on our health. Simultaneous analysis of 7 nitrosamines and 3 nitramines present in atmospheric particulate matter with an aerodynamic diameter less than or equal to the nominal value of 2.5 μm (PM2.5) at Seoul in the winter of 2018

To reduce the emissions from the iron and steel industry, China has imposed a series of strengthened emission standards since 2012. An accurate impact of emission reduction on the air quality is critical for evaluating policy efficiency. This study was the first attempt to explore the contribution of emissions from China's iron and steel industry to ambient air quality at national scale, after the

Recent updates to U.S. regulatory guidelines for modeling impacts of single sources to secondary pollutants, such as ozone (O3) and fine particulate matter (PM2.5), require the use of established photochemical models with a complete treatment of gas-phase and aerosol chemistry as the preferred method for a Tier 2 demonstration approach. Such models include photochemical grid models (PGMs), as well

One of the important products of MERRA-2 (Modern-Era Retrospective Analysis for Research and Applications) developed by NASA (National Aeronautics and Space Administration) is the long-term global records of surface PM2.5 mass concentration since 1980s, providing the ability of studying the interactions between air pollution, weather and climate changes. In this study, the PM2.5 mass concentrations

Atmospheric deposition (AD) is the transfer of soluble ions found in the atmosphere to the earth's surface by sedimentation (dry deposition) or by their inclusion or solution in raindrops (wet deposition, WAD). In this way, AD links the atmosphere with terrestrial ecosystems, being a key part of biogeochemical cycles. Although numerous investigations have quantified WAD, little is known about the temporal

Ten spatial surrogates describing the detailed locations of air pollution emissions in regional air quality assessments for California were updated/created for the base year 2010 and future years from 2015 to 2040: (i) total population, (ii) total housing, (iii) single-family housing, (iv) total employment, (v) service & commercial employment, (vi) industrial employment, (vii) agricultural employment

Atmospheric particle samples with aerodynamic diameter <10 μm (PM10) and <2.5 μm (PM2.5) were analyzed for elemental (EC), organic (OC) carbon and polar organic compounds. Samples were collected, on a daily basis, over 44 days during the winter period in Agia Maria Xyliatou, a background location of Cyprus. Polar organic compounds were determined using a 3-step derivatization method prior to analysis

We report a statistical analysis of surface ozone (O3) measurements over the UK, 1999–2019. Data are from the Automatic Urban and Rural Network (AURN) that forms the basis of checking nationwide compliance with ambient air quality directives. We determine the mean O3 trend across all AURN sites to be 0.41 ± 0.07 μg m−3yr−1, composed of larger trends in suburban and urban environments (0.36 ± 0.11 μg m−3yr−1–0

This paper provides the result of a parametric sensitivity study conducted on the atmospheric dispersion module of the Accident Damage Analysis Module for consequence assessment, developed by the European Commission to support the EU competent authorities for the implementation of the Seveso Directive in their countries or other legislation associated with chemical safety and security. A variance-based

Jack Rabbit II field trials recorded a large amount of point sensor data regarding meteorology and chlorine concentrations and included many video and specialized standoff measurements. Cloud dimensions must be inferred or analyzed from such data. The test data were used to identify cloud dimensions (widths and heights to the 20 and 200 ppm contours) for use in the model inter-comparison exercise.

Thermal-Optical Analysis (TOA), a commonly implemented technique used to measure the amount of particulate carbon in the atmosphere or deposited on a filter substrate, distinguishes organic carbon (OC) from elemental carbon (EC) through the monitoring of laser light, heating, and measuring evolved carbon. Here, we present a method to characterize the TOA transmission method with an aqueous binary mixture

The availability of low-cost monitors marketed for use in homes has increased rapidly over the past few years due to the advancement of sensing technologies, increased awareness of urban pollution, and the rise of citizen science. The user-friendly packages can make them appealing for use in research grade indoor exposure assessments, but a rigorous scientific evaluation has not been conducted for

Exhaust emissions from Euro 2-6a cars using diesel, gasoline, high concentration ethanol (E85) fuel and compressed natural gas (CNG) were studied comprehensively, with a focus on results obtained at −7 °C test temperature. Higher emissions than desired were noticed in some cases, e.g. elevated methane emissions from natural gas fuelled cars, as well as methane and acetaldehyde emissions from E85 fuelled