Search results for "POLLUTION"
showing 10 items of 2765 documents
Air pollution in European countries and life expectancy—modelling with the use of neural network
2019
Abstract The present paper discusses a novel methodology based on neural network to determine air pollutants’ correlation with life expectancy in European countries. The models were developed using historical data from the period 1992–2016, for a set of 20 European countries. The subject of the analysis included the input variables of the following air pollutants: sulphur oxides, nitrogen oxides, carbon monoxide, particulate matters, polycyclic aromatic hydrocarbons and non-methane volatile organic compounds. Our main findings indicate that all the variables significantly affect life expectancy. Sensitivity of constructed neural networks to pollutants proved to be particularly important in …
Aviation Contrail Cirrus and Radiative Forcing Over Europe During 6 Months of COVID‐19
2021
Abstract The COVID‐19 pandemic led to a 72% reduction of air traffic over Europe in March–August 2020 compared to 2019. Modeled contrail cover declined similarly, and computed mean instantaneous radiative contrail forcing dropped regionally by up to 0.7 W m−2. Here, model predictions of cirrus optical thickness and the top‐of‐atmosphere outgoing longwave and reflected shortwave irradiances are tested by comparison to Meteosat‐SEVIRI‐derived data. The agreement between observations and modeled data is slightly better when modeled contrail cirrus contributions are included. The spatial distributions and diurnal cycles of the differences in these data between 2019 and 2020 are partially caused…
Development of a simulation chamber for the evaluation of dermal absorption of volatile organic compounds
2020
Abstract An exposition chamber has been designed and developed for the production of contaminated atmospheres with fixed and known concentration of volatile organic compounds. The proposed chamber has been evaluated for the determination of in-vitro diffusion parameters, such as flux and lag time for benzene, toluene, ethylbenzene, and xylenes (BTEX). Polydimethylsiloxane (PDMS) and Strat-M® membranes were evaluated, including the effect of membrane thickness, from 0.5 to 3.0 mm, on the diffusion parameters. The obtained flux values and lag times, ranged from 0.2 to 1.5 μg cm−2 h−1 and from 10 to 130 min, respectively, for studies performed at a BTEX concentration of 51 μg L−1 in air. Diffe…
Origin of atmospheric aerosols at the Pierre Auger Observatory using studies of air mass trajectories in South America
2014
The Pierre Auger Observatory is making significant contributions towards understanding the nature and origin of ultra-high energy cosmic rays. One of its main challenges is the monitoring of the atmosphere, both in terms of its state variables and its optical properties. The aim of this work is to analyze aerosol optical depth $\tau_{\rm a}(z)$ values measured from 2004 to 2012 at the observatory, which is located in a remote and relatively unstudied area of the Pampa Amarilla, Argentina. The aerosol optical depth is in average quite low - annual mean $\tau_{\rm a}(3.5~{\rm km})\sim 0.04$ - and shows a seasonal trend with a winter minimum - $\tau_{\rm a}(3.5~{\rm km})\sim 0.03$ -, and a sum…
The Effect of the Covid-19 Lockdown on Air Quality in Three Italian Medium-Sized Cities
2020
Despite the societal and economic impacts of the COVID-19 pandemic, the lockdown measures put in place by the Italian government provided an unprecedented opportunity to increase our knowledge of the effect transportation and industry-related emissions have on the air quality in our cities. This study assessed the effect of reduced emissions during the lockdown period, due to COVID-19, on air quality in three Italian cities, Florence, Pisa, and Lucca. For this study, we compared the concentration of particulate matter PM10, PM2.5, NO2, and O3 measured during the lockdown period, with values obtained in the same period of 2019. Our results show no evidence of a direct relationship between th…
δ13C variations in tree rings as an indication of severe changes in the urban air quality
2002
Abstract Annual growth rings sampled from three free-standing trees (Platanus hybrida sp.), grew in the metropolitan area of Palermo (Italy) and covering a 118 years time span (1880–1998), have been studied for their 13C/12C carbon isotope ratios. It has been found that the 13C/12C tree ring record, during the study time interval, decreased of −3.6‰, from −26.4‰ in 1880 to −30‰ in 1998. Such a progressive depletion has been attributed to the addition of anthropogenic 13C depleted carbon dioxide to the local atmosphere. The observed 13C/12C decrease has been used to infer some possible pathways of atmospheric CO2 change in the study urban area.
Outdoor, indoor and personal distribution of BTEX in pregnant women from two areas in Spain - Preliminary results from the INMA project
2010
Volatile organic compounds (VOCs), which are habitually found in both outdoor and indoor environments, may represent a significant health risk. In this context, pregnancy is a critical period since foetuses are more vulnerable than adults to exposure to toxic compounds. The objective of this study is to present the preliminary results of a series of measurements of outdoor (O), indoor (I) and personal exposure (P) to benzene, toluene, ethylbenzene, o-xylene and m,p-xylene (BTEX) in 107 pregnant women from two areas in Spain, namely Valencia and Sabadell. BTEX samplers were installed for 48 hours both inside and outside of the women’s homes, along with personal samplers. In addition, the tes…
Study on ambient concentrations of PM10, PM10-2.5, PM2.5 and gaseous pollutants. Trace elements and chemical speciation of atmospheric particulates
2010
Abstract This study provides the first comprehensive report on mass concentrations of particulate matter of various sizes, inorganic and organic gas concentrations monitored at three sampling sites in the city of Palermo (Sicily, Italy). It also provides information on the water-soluble species and trace elements. A total of 2054 PM10 (1333) and PM2.5 (721) daily measurements were collected from November 2006 to February 2008. The highest mass concentrations were observed at the urban stations, average values being about two times higher than those at the suburban (control) site. Time variations in PM10 and also PM10–2.5 were observed at the urban stations, the highest concentrations being …
Spatial distribution of aerosol microphysical and optical properties and direct radiative effect from the China Aerosol Remote Sensing Network
2019
Multi-year observations of aerosol microphysical and optical properties, obtained through ground-based remote sensing at 50 China Aerosol Remote Sensing Network (CARSNET) sites, were used to characterize the aerosol climatology for representative remote, rural, and urban areas over China to assess effects on climate. The annual mean effective radii for total particles (ReffT) decreased from north to south and from rural to urban sites, and high total particle volumes were found at the urban sites. The aerosol optical depth at 440 nm (AOD440 nm) increased from remote and rural sites (0.12) to urban sites (0.79), and the extinction Ångström exponent (EAE440–870 nm) increased fro…
Mass levels, crustal component and trace elements in PM10 in Palermo, Italy.
2007
Abstract Results concerning the levels and elemental compositions of daily PM 10 samples collected at four air quality monitoring sites in Palermo (Italy) are presented. The highest mean value of PM 10 concentrations (46 μg m −3 , with a peak value of 158 μg m −3 ) was recorded at the Di Blasi urban station, and the lowest at Boccadifalco station (25 μg m −3 ), considered as a sub-urban background station. Seventeen elements (Al, As, Ba, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Sb, Sr, U, V, Zn) were measured by ICP-MS. Al and Fe showed the highest concentrations, indicating the significant contribution of soil and resuspended mineral particles to atmospheric PM 10 . Ba, Cr, Cu, Mn, Mo, Ni, Pb, …