Severe PM10 (particulate matter with a diameter of <10 μm) events in South Korea are known to be caused by stable atmospheric circulation conditions related to high-pressure anomalies in the upper ...troposphere. However, research on why these atmospheric circulation patterns occur is unknown. In this study, we propose new large-scale teleconnection pathways that cause severe PM10 events during the midwinter in South Korea. This study investigated instances of extremely high (EH)-PM10 in South Korea during mid-winter and examined the corresponding atmospheric teleconnection patterns to identify the factors contributing to EH-PM10 events. K-means clustering analysis revealed that EH-PM10 instances were associated with two large-scale teleconnection patterns. Cluster 1 exhibited a wave train pattern originating in the North Atlantic that developed from Eurasia to the Korean Peninsula. Cluster 2 was associated with a wave-like teleconnection pattern from the Barents-Kara Sea to the Korean Peninsula. The Rossby waves, triggered by the North Atlantic and the Arctic, propagated and weakened the surface pressure system. This led to a high-pressure anomaly over the Korean Peninsula, reducing atmospheric ventilation and causing a rapid increase in PM10 concentration within a few days. Furthermore, an experiment involving a linear baroclinic model established that atmospheric forcing in upstream regions has the potential to induce large-scale atmospheric teleconnection patterns, resulting in EH-PM10 cases in South Korea. These findings emphasize the ventilation effect and transport of PM10 concentrations modulated by two large-scale teleconnection patterns originating from the Arctic and North Atlantic, leading to EH-PM10 events in South Korea. Understanding this combined phenomenon may assist in the implementation of emission reduction measures based on the results of short-term forecasts of severe PM10 events.
Display omitted
•Impact of teleconnection patterns on extremely high (EH) PM10 days is unknown.•We suggest new teleconnection patterns associated with EH-PM10 events in South Korea.•Two teleconnection patterns affect EH-PM10 cases in S. Korea.•Rossby wave energy from North Atlantic and Barents–Kara Sea propagates to S. Korea.•Large-scale teleconnection patterns reduced ventilation, causing EH-PM10 events.
The first COVID-19 case in Brazil was confirmed on February 25, 2020. On March 16, the state's governor declared public health emergency in the city of Rio de Janeiro and partial lockdown measures ...came into force a week later. The main goal of this work is to discuss the impact of the measures on the air quality of the city by comparing the particulate matter, carbon monoxide, nitrogen dioxide and ozone concentrations determined during the partial lockdown with values obtained in the same period of 2019 and also with the weeks prior to the virus outbreak. Concentrations varied with substantial differences among pollutants and also among the three studied monitoring stations. CO levels showed the most significant reductions (30.3–48.5%) since they were related to light-duty vehicular emissions. NO2 also showed reductions while PM10 levels were only reduced in the first lockdown week. In April, an increase in vehicular flux and movement of people was observed mainly as a consequence of the lack of consensus about the importance and need of social distancing and lockdown. Ozone concentrations increased probably due to the decrease in nitrogen oxides level. When comparing with the same period of 2019, NO2 and CO median values were 24.1–32.9 and 37.0–43.6% lower. Meteorological interferences, mainly the transport of pollutants from the industrial areas might have also impacted the results.
Display omitted
•CO levels showed the most significant reductions during the partial lockdown.•NO2 decreased in a lower extent, due to industrial and diesel input.•PM10 levels were only reduced during the first partial lockout week.•Ozone increased due to the decrease in nitrogen oxides level in a VOC-controlled scenario.
A dust storm that formed in the north of China and the southeastern part of Mongolia in March 2021 significantly deteriorated air quality over a large area of East Asia. According to the synoptic ...pattern, the cause of the dust storm was a cyclone with a significant drop in pressure leading to high winds and dry components of the soil over parts of the Gobi Desert becoming airborne. Data obtained from ground-based air quality monitoring stations show that the observed hourly PM10 concentration greatly exceeded the recommended maximum of 150 μg/m3 with readings above 1500 μg/m3 in the cities of Tianjin, Baoding, Zhengzhou, Luoyang, Zhoukou. In Shijiazhuang, Taiyuan, Jinnan, Xining, Baotou, and Jining. In Handan, it was over 2000 μg/m3. Cities where PM10 concentration exceeded 3900 μg/m3 included Lanzhou, Hohhot, Changzhou, Alashan, Yan'an, Yulin, Hami, Jiuquan, Heze, Hotan, and Baiyin. Concentrations exceeded 7000 μg/m3 on March 15th over parts of the provinces of Inner Mongolia, Gansu and Ningxia, in the cities of Ordos, Jinchang, Wuwei and Zhongwei. According to satellite data, the area of dust covered approximately 450,000 km2. MODIS and TROPOMI data demonstrated high aerosol optical depth (AOD) (more than 1) with a high ultraviolet aerosol index (UVAI) (more than 2), confirming the predominance of dust particles during the storm. Data from CALIPSO show the presence of a dense layer of dust extending from the earth's surface to a height of about 8 km. The Dust Regional Atmospheric Model (BSC-DREAM8b) demonstrates high synchrony with the satellite's surface dust concentration data, ranging from 640 to 1280 μg/m3, and exceeding 2650 μg/m3 in some areas. The purpose of this study is to analyze data from ground-based sensors, satellites, and atmospheric models to better understand the March 2021 dust storm event. The results may be useful for the implementation of protective and preventive measures for both the environment and human health, including air quality control.
Display omitted
•Multi-satellite observation of an intense dust event.•One of the most heavy dust storm of the last 10 years.•Spatial and temporal variations of air pollutants and aerosol properties were analyzed.•PM10 concentration was above 1500 μg/m3 in many cities.
Based on the rapid spread of the CoViD-2019, a lockdown was declared in the whole Northern Italy by the Government. The application of increasingly rigorous containment measures allowed to reduce the ...impact of the CoViD-2019 pandemic on the Italian National Health System but at the same time these restriction measures gave also the opportunity to assess the effect of anthropogenic activities on air pollutants in an unprecedented way. This paper aims to study the impact of the partial and total lockdown (PL and TL, respectively) on air quality in the Metropolitan City of Milan. As results, the severe limitation of people movements following the PL and the subsequent TL determined a significant reduction of pollutants concentration mainly due to vehicular traffic (PM10, PM2.5, BC, benzene, CO, and NOx). The lockdown led to an appreciable drop in SO2 only in the city of Milan while it remained unchanged in the adjacent areas. Despite the significant decrease in NO2 in the TL, the O3 exhibited a significant increase, probably, due to the minor NO concentration. In Milan and SaA the increase was more accentuated, probably, due to the higher average concentrations of benzene in Milan than the adjacent areas that might have promoted the formation of O3 in a more significant way.
Display omitted
•The effect of lockdown on air quality in Milan was assessed.•The trends of 9 pollutants in meteorologically comparable periods were studied.•Lockdown determined a significant reduction of PM10, PM2.5, BC, benzene, CO and NOx.•SO2 remained unchanged in the more peripheral areas.•Part of the ozone increase was probably due to the lower NO measured during lockdown.
For reducing health impacts from air pollution, it is important to know the sources contributing to human exposure. This study systematically reviewed and analysed available source apportionment ...studies on particulate matter (of diameter of 10 and 2.5 microns, PM10 and PM2.5) performed in cities to estimate typical shares of the sources of pollution by country and by region. A database with city source apportionment records, estimated with the use of receptor models, was also developed and available at the website of the World Health Organization.
Systematic Scopus and Google searches were performed to retrieve city studies of source apportionment for particulate matter. Six source categories were defined. Country and regional averages of source apportionment were estimated based on city population weighting.
A total of 419 source apportionment records from studies conducted in cities of 51 countries were used to calculate regional averages of sources of ambient particulate matter. Based on the available information, globally 25% of urban ambient air pollution from PM2.5 is contributed by traffic, 15% by industrial activities, 20% by domestic fuel burning, 22% from unspecified sources of human origin, and 18% from natural dust and salt. The available source apportionment records exhibit, however, important heterogeneities in assessed source categories and incompleteness in certain countries/regions.
Traffic is one important contributor to ambient PM in cities. To reduce air pollution in cities and the substantial disease burden it causes, solutions to sustainably reduce ambient PM from traffic, industrial activities and biomass burning should urgently be sought. However, further efforts are required to improve data availability and evaluation, and possibly to combine with other types of information in view of increasing usefulness for policy making.
Display omitted
•Typical shares of the ambient sources of PM2.5 by country and by region were estimated.•Traffic has been targeted as important contributor to ambient air pollution in cities.•A database for Source Apportionment studies as of August 2014 has been compiled.
The novel coronavirus disease (COVID-19) is a highly pathogenic, transmittable and invasive pneumococcal disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which emerged ...in December 2019 and January 2020 in Wuhan city, Hubei province, China and fast spread later on the middle of February 2020 in the Northern part of Italy and Europe.
This study investigates the correlation between the degree of accelerated diffusion and lethality of COVID-19 and the surface air pollution in Milan metropolitan area, Lombardy region, Italy. Daily average concentrations of inhalable particulate matter (PM) in two size fractions PM2.5, PM10 and maxima PM10 ground level atmospheric pollutants together air quality and climate variables (daily average temperature, relative humidity, wind speed, atmospheric pressure field and Planetary Boundary Layer-PBL height) collected during 1 January–30 April 2020 were analyzed. In spite of being considered primarily transmitted by indoor bioaerosols droplets and infected surfaces, or direct human-to-human personal contacts, it seems that high levels of urban air pollution, weather and specific climate conditions have a significant impact on the increased rates of confirmed COVID-19 Total number, Daily New and Total Deaths cases, possible attributed not only to indoor but also to outdoor airborne bioaerosols distribution. Our analysis demonstrates the strong influence of daily averaged ground levels of particulate matter concentrations, positively associated with average surface air temperature and inversely related to air relative humidity on COVID-19 cases outbreak in Milan. Being a novel pandemic coronavirus (SARS-CoV-2) version, COVID-19 might be ongoing during summer conditions associated with higher temperatures and low humidity levels. Presently is not clear if this protein “spike” of the new coronavirus COVID-19 is involved through attachment mechanisms on indoor or outdoor airborne aerosols in the infectious agent transmission from a reservoir to a susceptible host in some agglomerated urban areas like Milan is.
Display omitted
•COVID-19 daily New cases are positively related with PM and Air Quality Index.•Dry air supports COVID-19 virus transmission.•Warm season will not stop COVID-19 spreading.•Outdoor airborne aerosols might be possible routes of COVID-19 diffusion.
Comparison of fine and coarse fractions in terms of sources and dynamics is scarce in southeast Mediterranean countries; differences are relevant because of the importance of natural sources like sea ...spray and Saharan dust advection, because most of the monitoring networks are limited to PM10. In this work, the main seasonal variabilities of sources and processes involving fine and coarse PM (particulate matter) were studied at the Environmental-Climate Observatory of Lecce (Southern Italy). Simultaneous PM2.5 and PM10 samples were collected between July 2013 and July 2014 and chemically analysed to determine concentrations of several species: OC (organic carbon) and EC (elemental carbon) via thermo-optical analysis, 9 major ions via IC, and 23 metals via ICP-MS. Data was processed through mass closure analysis and Positive Matrix Factorization (PMF) receptor model characterizing seasonal variabilities of nine sources contributions. Organic and inorganic secondary aerosol accounts for 43% of PM2.5 and 12% of PM2.5–10 with small seasonal changes. SIA (secondary inorganic aerosol) seasonal pattern is opposite to that of SOC (secondary organic carbon). SOC is larger during the cold period, sulphate (the major contributor to SIA) is larger during summer. Two forms of nitrate were identified: NaNO3, correlated with chloride depletion and aging of sea-spray, mainly present in PM2.5–10; NH4NO3 more abundant in PM2.5. Biomass burning is a relevant source with larger contribution during autumn and winter because of the influence of domestic heating, however, is not negligible in spring and summer, because of the contributions of fires and agricultural practices. Mass closure analysis and PMF results identify two soil sources: crustal associated to long range transport and carbonates associated to local resuspended dust. Both sources contributes to the coarse fraction and have different dynamics with crustal source contributing mainly in high winds from SE conditions and carbonates during high winds from North direction.
Display omitted
•Composition and sources of PM2.5 and PM2.5–10 are investigated in South-eastern Italy.•Secondary organic and inorganic components were 43% of PM2.5 with opposite seasonal trends.•Two forms of nitrate were observed: sodium nitrate and ammonium nitrate (only in winter).•PMF and mass-closure identified two soil sources accounting for 29% of PM2.5–10.•Biomass burning is an important source at the urban background site even during warm seasons.
The 2001–2016 contribution of African dust outbreaks to ambient regional background PM10 and PM2.5 levels over Spain, as well as changes induced in the PMx composition over NE Spain in 2009–2016, ...were investigated. A clear decrease in PMx dust contributions from the Canary Islands to N Iberia was found. A parallel increase in the PM2.5/PM10 ratio (30% in the Canary Islands to 57% in NW Iberia) was evidenced, probably due to size segregation and the larger relative contribution of the local PMx with increasing distance from Africa.
PM1–10 and PM2.5–10 measured in Barcelona during African dust outbreaks (ADOs) were 43–46% higher compared to non-ADO days. The continental background contribution prevailed in terms of both PM1–10 and PM2.5–10 during ADO days (62 and 69%, respectively, and 31 and 27% for non-ADO days). The relative contributions of Al2O3/Fe2O3/CaO to PMx fraction showed that Al2O3 is a suitable tracer for African dust in our context; while CaO at the urban site is clearly affected by local resuspension, construction and road dust, and Fe2O3 by dust from vehicle brake discs. The results also provide evidence that PM increases during ADOs are caused not only by the mineral dust load, but by an increased accumulation of locally emitted or co-transported anthropogenic pollutants as compared with non-ADO days. Possible causes for this accumulation are discussed. We recommend that further epidemiological studies should explore independently the potential effects of mineral dust and the anthropogenic PM during ADOs, because, at least over SW Europe, not only mineral dust affects the air quality during African dust episodes.
Display omitted
•African dust transport affects air quality of Spain during 9 (NW Iberia) to 31 (Canary Islands)% of days.•PM10 & PM2.5 levels increase by 9 to 29 and 5 to 29 µg/m3 PM10 and PM2.5 from NW Iberia to the Canary Islands.•PM speciation shows that this increase is due to mineral dust and anthropogenic PM co-transported or locally accumulated.•For epidemiological studies the two fractions have to be studied with regards the evaluation of possible health effects.
Biomass burning is considered a renewable energy source whose household usage is rapidly increasing throughout Europe, largely encouraged by the rising cost of other energy sources. With all the ...advantages that characterize such an energy source, there are several disadvantages mostly from the air quality standpoint, and consequently with regard to the influence it may have on human health and climate change. Considering the side effects of air pollution, it is important to identify the composition and sources of air pollutants precisely. This study investigated the presence of biomass combustion-specific tracers in the air of Zagreb, Croatia, a city affected by increased air pollution mostly during wintertime. Biomass burning markers in terms of anhydrosugars, namely levoglucosan, mannosan, and galactosan were monitored in particulate matter PM10. A sampling of PM10 particulate matter was conducted in parallel at measuring stations in the northern and southern part of the city during 30 days in each season in 2020. The results showed a significant seasonal difference in PM10 and anhydrosugar levels at both measuring stations with the same seasonal trend decreasing as follows: winter, autumn, spring, summer. Both PM10 and anhydrosugar concentrations were higher in the southern compared to the northern station. Average winter PM10 levels were 58 μg m−3 at the southern and 51 μg m−3 at the northern station, while average levoglucosan levels were 3.68 and 1.64 μg m−3 at the southern and northern stations, respectively. An average levoglucosan/PM10 contribution of 6.3 % was determined at the southern, and 3.2 % at the northern measuring station. The differences in contribution can be explained by areas more populated by households using biomass for residential heating, the dominant wind direction in the area, and influences from other districts, including long- or close-range transport. Linear regression indicated a weak correlation (R2 = 0.32) of anhydrosugars between the stations.
•The first data on specific biomass-burning tracers in Zagreb, Croatia were measured.•Higher anhydrosugars levels were measured in the southern part of the city.•The seasonal anhydrosugars trend: winter > autumn > spring > summer.•Levoglucosan was the most dominant anhydrosugar compound.•The LG/MN ratio revealed the use of different types of biomass in different seasons.
PDF
