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Quantitative chemical analysis of airborne particulate matter (PM) is vital for the understanding of health effects in indoor and outdoor environments, as well as for enforcing EU air quality regulations. Typically, airborne particles are sampled over long time periods on filters, followed by lab-based analysis, e.g., with inductively coupled plasma mass spectrometry (ICP-MS). During the EURAMET EMPIR AEROMET project, cascade impactor aerosol sampling is combined for the first time with on-site total reflection X-ray fluorescence (TXRF) spectroscopy to develop a tool for quantifying particle element compositions within short time intervals and even on-site. This makes variations of aerosol chemistry observable with time resolution only a few hours and with good size resolution in the PM10 range. The study investigates the proof of principles of this methodological approach. Acrylic discs and silicon wafers are shown to be suitable impactor carriers with sufficiently smooth and clean surfaces, and a non-destructive elemental mass concentration measurement with a lower limit of detection around 10 pg/m3 could be achieved. We demonstrate the traceability of field TXRF measurements to a radiometrically calibrated TXRF reference, and the results from both analytical methods correspond satisfactorily.
MDPI
2021
An optimized low volume sampler was developed to determine both gas- and particle bound concentrations of short and medium-chain chlorinated paraffins (S/MCCPs). Background contamination was limited by the sampler design, providing method quantification limits (MQLs) at least two orders of magnitude lower than other studies within the gas (MQL: 500 pg (ΣSCCPs), 1.86 ng (ΣMCCPs)) and particle (MQL: 500 pg (ΣSCCPs), 1.72 ng (ΣMCCPs) phases. Good repeatability was observed between parallel indoor measurements (RSD ≤ 9.3% (gas), RSD ≤ 14% (particle)) with no breakthrough/saturation observed after a week of continuous sampling. For indoor air sampling, SCCPs were dominant within the gas phase (17 ± 4.9 ng/m3) compared to MCCPs (2.7 ± 0.8 ng/m3) while the opposite was observed in the particle bound fraction (0.28 ± 0.11 ng/m3 (ΣSCCPs) vs. 2.7 ± 1.0 ng/m3 (ΣMCCPs)). Only SCCPs in the gas phase could be detected reliably during outdoor sampling and were considerably lower compared to indoor concentrations (0.27 ± 0.10 ng/m3). Separation of the gas and particle bound phase was found to be crucial in applying the appropriate response factors for quantification based on the deconvoluted S/MCCP sample profile, thus avoiding over- (gas phase) or underestimation (particle phase) of reported concentrations. Very short chain chlorinated paraffins (vSCCPs, C5-C9) were also detected at equal or higher abundance compared to SCCP congener groups (C10-C13) congener groups, indicating an additional human indoor inhalation risk.
Elsevier
2021
Although it has been suggested that plastic may act as a vector for pollutants into the tissue of seabirds, the bioaccumulation of harmful contaminants, such as polybrominated diphenyl ethers (PBDEs), released from ingested plastics is poorly understood. Plastic ingestion by the procellariiform species northern fulmar (Fulmarus glacialis) is well documented. In this study, we measured PBDEs levels in liver tissue of northern fulmars without and with (0.13–0.43 g per individual) stomach plastics. PBDE concentrations in the plastic sampled from the same birds were also quantified. Birds were either found dead on beaches in southern Norway or incidentally caught in longline fisheries in northern Norway. PBDEs were detected in all birds but high concentrations were only found in liver samples from beached birds, peaking at 2900 ng/g lipid weight. We found that body condition was a significant factor explaining the elevated concentration levels in livers of beached birds. BDE209 was found in ingested plastic particles and liver tissue of birds with ingested plastics but was absent in the livers of birds without ingested plastics. This strongly suggests a plastic-derived transfer and accumulation of BDE209 to the tissue of fulmars, levels of which might prove useful as a general indicator of plastic ingestion in seabirds.
Elsevier
2021
A comprehensive European dataset on monthly atmospheric NH3, acid gases (HNO3, SO2, HCl), and aerosols (NH+4, NO−3, SO2−4, Cl−, Na+, Ca2+, Mg2+) is presented and analysed. Speciated measurements were made with a low-volume denuder and filter pack method (DEnuder for Long-Term Atmospheric sampling, DELTA®) as part of the EU NitroEurope (NEU) integrated project. Altogether, there were 64 sites in 20 countries (2006–2010), coordinated between seven European laboratories. Bulk wet-deposition measurements were carried out at 16 co-located sites (2008–2010). Inter-comparisons of chemical analysis and DELTA® measurements allowed an assessment of comparability between laboratories.
The form and concentrations of the different gas and aerosol components measured varied between individual sites and grouped sites according to country, European regions, and four main ecosystem types (crops, grassland, forests, and semi-natural). The smallest concentrations (with the exception of SO2−4 and Na+) were in northern Europe (Scandinavia), with broad elevations of all components across other regions. SO2 concentrations were highest in central and eastern Europe, with larger SO2 emissions, but particulate SO2−4 concentrations were more homogeneous between regions. Gas-phase NH3 was the most abundant single measured component at the majority of sites, with the largest variability in concentrations across the network. The largest concentrations of NH3, NH+4, and NO−3 were at cropland sites in intensively managed agricultural areas (e.g. Borgo Cioffi in Italy), and the smallest were at remote semi-natural and forest sites (e.g. Lompolojänkkä, Finland), highlighting the potential for NH3 to drive the formation of both NH+4 and NO−3 aerosol. In the aerosol phase, NH+4 was highly correlated with both NO−3 and SO2−4, with a near-1:1 relationship between the equivalent concentrations of NH+4 and sum (NO−3+ SO2−4),of which around 60 % was as NH4NO3.
Distinct seasonality was also observed in the data, influenced by changes in emissions, chemical interactions, and the influence of meteorology on partitioning between the main inorganic gases and aerosol species. Springtime maxima in NH3 were attributed to the main period of manure spreading, while the peak in summer and trough in winter were linked to the influence of temperature and rainfall on emissions, deposition, and gas–aerosol-phase equilibrium. Seasonality in SO2 was mainly driven by emissions (combustion), with concentrations peaking in winter, except in southern Europe, where the peak occurred in summer. Particulate SO2−4 showed large peaks in concentrations in summer in southern and eastern Europe, contrasting with much smaller peaks occurring in early spring in other regions. The peaks in particulate SO2−4 coincided with peaks in NH3 concentrations, attributed to the formation of the stable (NH4)2SO4. HNO3 concentrations were more complex, related to traffic and industrial emissions, photochemistry, and HNO3:NH4NO3 partitioning. While HNO3 concentrations were seen to peak in the summer in eastern and southern Europe (increased photochemistry), the absence of a spring peak in HNO3 in all regions may be explained by the depletion of HNO3 through reaction with surplus NH3 to form the semi-volatile aerosol NH4NO3. Cooler, wetter conditions in early spring favour the formation and persistence of NH4NO3 in the aerosol phase, consistent with the higher springtime concentrations of NH+4 and NO−3. The seasonal profile of NO−3 was mirrored by NH+4, illustrating the influence of gas–aerosol partitioning of NH4NO3 in the seasonality of these components.
Gas-phase NH3 and aerosol NH4NO3 were the dominant species in the total inorganic gas and aerosol species measured in the NEU network. With the current and projected trends in SO2, NOx, and NH3 emissions, concentrations of NH3 and NH4NO3 can be expected to continue to dominate...
2021
Unexpected nascent atmospheric emissions of three ozone-depleting hydrochlorofluorocarbons
Global and regional atmospheric measurements and modeling can play key roles in discovering and quantifying unexpected nascent emissions of environmentally important substances. We focus here on three hydrochlorofluorocarbons (HCFCs) that are restricted by the Montreal Protocol because of their roles in stratospheric ozone depletion. Based on measurements of archived air samples and on in situ measurements at stations of the Advanced Global Atmospheric Gases Experiment (AGAGE) network, we report global abundances, trends, and regional enhancements for HCFC-132b (CH2ClCClF2), which is newly discovered in the atmosphere, and updated results for HCFC-133a (CH2ClCF3) and HCFC-31 (CH2ClF). No purposeful end-use is known for any of these compounds. We find that HCFC-132b appeared in the atmosphere 20 y ago and that its global emissions increased to 1.1 Gg⋅y−1 by 2019. Regional top-down emission estimates for East Asia, based on high-frequency measurements for 2016–2019, account for ∼95% of the global HCFC-132b emissions and for ∼80% of the global HCFC-133a emissions of 2.3 Gg⋅y−1 during this period. Global emissions of HCFC-31 for the same period are 0.71 Gg⋅y−1. Small European emissions of HCFC-132b and HCFC-133a, found in southeastern France, ceased in early 2017 when a fluorocarbon production facility in that area closed. Although unreported emissive end-uses cannot be ruled out, all three compounds are most likely emitted as intermediate by-products in chemical production pathways. Identification of harmful emissions to the atmosphere at an early stage can guide the effective development of global and regional environmental policy.
2021
DNA repair gene polymorphisms and chromosomal aberrations in healthy, nonsmoking population
Elsevier
2021
Changes in black carbon emissions over Europe due to COVID-19 lockdowns
Following the emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for COVID-19 in December 2019 in Wuhan (China) and its spread to the rest of the world, the World Health Organization declared a global pandemic in March 2020. Without effective treatment in the initial pandemic phase, social distancing and mandatory quarantines were introduced as the only available preventative measure. In contrast to the detrimental societal impacts, air quality improved in all countries in which strict lockdowns were applied, due to lower pollutant emissions. Here we investigate the effects of the COVID-19 lockdowns in Europe on ambient black carbon (BC), which affects climate and damages health, using in situ observations from 17 European stations in a Bayesian inversion framework. BC emissions declined by 23 kt in Europe (20 % in Italy, 40 % in Germany, 34 % in Spain, 22 % in France) during lockdowns compared to the same period in the previous 5 years, which is partially attributed to COVID-19 measures. BC temporal variation in the countries enduring the most drastic restrictions showed the most distinct lockdown impacts. Increased particle light absorption in the beginning of the lockdown, confirmed by assimilated satellite and remote sensing data, suggests residential combustion was the dominant BC source. Accordingly, in central and Eastern Europe, which experienced lower than average temperatures, BC was elevated compared to the previous 5 years. Nevertheless, an average decrease of 11 % was seen for the whole of Europe compared to the start of the lockdown period, with the highest peaks in France (42 %), Germany (21 %), UK (13 %), Spain (11 %) and Italy (8 %). Such a decrease was not seen in the previous years, which also confirms the impact of COVID-19 on the European emissions of BC.
2021
Svalbard Integrated Arctic Earth Observing System (SIOS) is an international partnership of research institutions studying the environment and climate in and around Svalbard. SIOS is developing an efficient observing system, where researchers share technology, experience, and data, work together to close knowledge gaps, and decrease the environmental footprint of science. SIOS maintains and facilitates various scientific activities such as the State of the Environmental Science in Svalbard (SESS) report, international access to research infrastructure in Svalbard, Earth observation and remote sensing services, training courses for the Arctic science community, and open access to data. This perspective paper highlights the activities of SIOS Knowledge Centre, the central hub of SIOS, and the SIOS Remote Sensing Working Group (RSWG) in response to the unprecedented situation imposed by the global pandemic coronavirus (SARS-CoV-2) disease 2019 (COVID-19). The pandemic has affected Svalbard research in several ways. When Norway declared a nationwide lockdown to decrease the rate of spread of the COVID-19 in the community, even more strict measures were taken to protect the Svalbard community from the potential spread of the disease. Due to the lockdown, travel restrictions, and quarantine regulations declared by many nations, most physical meetings, training courses, conferences, and workshops worldwide were cancelled by the first week of March 2020. The resumption of physical scientific meetings is still uncertain in the foreseeable future. Additionally, field campaigns to polar regions, including Svalbard, were and remain severely affected. In response to this changing situation, SIOS initiated several operational activities suitable to mitigate the new challenges resulting from the pandemic. This article provides an extensive overview of SIOS’s Earth observation (EO), remote sensing (RS) and other operational activities strengthened and developed in response to COVID-19 to support the Svalbard scientific community in times of cancelled/postponed field campaigns in Svalbard. These include (1) an initiative to patch up field data (in situ) with RS observations, (2) a logistics sharing notice board for effective coordinating field activities in the pandemic times, (3) a monthly webinar series and panel discussion on EO talks, (4) an online conference on EO and RS, (5) the SIOS’s special issue in the Remote Sensing (MDPI) journal, (6) the conversion of a terrestrial remote sensing training course into an online edition, and (7) the announcement of opportunity (AO) in airborne remote sensing for filling the data gaps using aerial imagery and hyperspectral data. As SIOS is a consortium of 24 research institutions from 9 nations, this paper also presents an extensive overview of the activities from a few research institutes in pandemic times and highlights our upcoming activities for the next year 2021. Finally, we provide a critical perspective on our overall response, possible broader impacts, relevance to other observing systems, and future directions. We hope that our practical services, experiences, and activities implemented in these difficult times will motivate other similar monitoring programs and observing systems when responding to future challenging situations. With a broad scientific audience in mind, we present our perspective paper on activities in Svalbard as a case study.
Earth observation; Remote sensing; COVID-19; Svalbard; Earth System Science; SIOS
MDPI
2021
Using the Super Dual Auroral Radar Network observations (clustered around 60°N) and NCAR CESM2.0 extended Whole Atmosphere Community Climate Model nudged with reanalyzes, we examine the climatology of semidiurnal tides in meridional wind associated with the migrating component (SW2) and non‐migrating components of wavenumbers 1 (SW1) and 3 (SW3). We then illustrate their composite response to major sudden stratospheric warmings (SSWs). Peaking in late summer and winter, the climatological SW2 amplitude exceeds SW1 and SW3 except around late Fall and Spring. The winter climatological peak is absent in the model perhaps due to the zonal wind bias at the observed altitudes. The observed SW2 amplitude declines after SSW onset before enhancing ∼10 days later, along with SW1 and SW3. Within the observed region, the simulated SW2 only amplifies after SSW onset, with minimal SW1 and SW3 responses. The model reveals a stronger SW2 response above the observed location, with diminished amplitude before and enhancement after SSW globally. This enhancement appears related to increased equatorial ozone heating and background wind symmetry. The strongest SW1 and SW3 growth occurs in the Southern Hemisphere before SSW. SW2 and quasi‐stationary planetary wave activities are temporally collocated during SSW suggesting that their interactions excite SW1 and SW3. After SSW, the model also reveals (1) semidiurnal‐tide‐like perturbations generated possibly by the interactions between SW2 and westward‐traveling disturbances and (2) the enhancement of migrating semidiurnal lunar tide in the Northern Hemisphere that exceeds non‐migrating tidal and semidiurnal‐tide‐like responses. The simulated eastward‐propagating semidiurnal tides are briefly examined.
American Geophysical Union (AGU)
2021
Royal Society of Chemistry (RSC)
2021