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Overvåkning av klimagasser og partikler på Svalbard og Birkenes i 2023. Årsrapport
No full textThis annual report for 2023 summarizes the activities and results of the greenhouse gas monitoring at the Zeppelin Observatory, situated on Svalbard, during the period 2001-2023, and the greenhouse gas monitoring and aerosol observations from Birkenes for 2009-2023.Denne årsrapporten for 2023 presenterer aktiviteter og måleresultater fra klimagassovervåkingen ved Zeppelinobservatoriet på Svalbard for årene 2001-2023 og klimagassmålinger og klimarelevante partikkelmålinger fra Birkenes for 2009-2023.publishedVersio
Undersøkelse av snødrevet deponering av sykliske siloksaner i et Arktisk miljø
No full textcVMS are high production volume chemicals that are used for a wide range of industrial and domestic applications. Given the high volatility of cVMS, emissions occur mainly to the atmosphere, and cVMS are present in the Arctic atmosphere, e.g. at the Zeppelin Observatory near Ny Ålesund, Svalbard, suggesting potential for long-range atmospheric transport. A study to investigate whether cVMS have the potential to deposit to surface media, and thereby represent a potential risk to the terrestrial or marine environment in polar and Arctic regions was carried out. Overall, cVMS levels in samples of vegetation, soil, sediment and marine biota were low. D4 was detected in most samples at concentrations above LOD, but below LOQ, while D5 and D6 were generally not detected. The low cVMS concentrations in soil, vegetation, sediments, and fish are in line with most current research on cVMS in remote regions, which together suggest that input of cVMS from atmospheric deposition and snow melt is likely not a major contributing source.VMS er kjemikalier med høyt produksjonsvolum som brukes til et bredt spekter av industrielle og husholdningsapplikasjoner. Gitt den høye flyktigheten til cVMS, skjer utslipp hovedsakelig til atmosfæren, og cVMS er til stede i den arktiske atmosfæren, for eksempel ved Zeppelinobservatoriet nær Ny-Ålesund, Svalbard, noe som antyder potensial for langtransport i atmosfæren. En studie for å undersøke om cVMS har potensial til å avsettes til overflatemedia, og dermed representere en potensiell risiko for det terrestriske eller marine miljøet i polar- og arktiske regioner ble derfor utført. Totalt sett var cVMS-nivåene i prøver av vegetasjon, jord, sediment og marine organismer lave. D4 ble påvist i de fleste prøvene ved konsentrasjoner over LOD, men under LOQ, mens D5 og D6 generelt ikke ble påvist. De lave cVMS-konsentrasjonene i jord, vegetasjon, sedimenter og fisk er i tråd med de fleste tidligere studier på cVMS i avsidesliggende områder, som sammen antyder at tilførsel av cVMS fra atmosfærisk avsetning og snøsmelting sannsynligvis ikke er en stor bidragskilde.publishedVersio
Status report 2024. National reference laboratory for air quality monitoring
No full textDenne rapporten oppsummerer oppgavene til Nasjonalt referanselaboratorium for luftkvalitetsmålinger (NRL), delkontrakt 1b, for første halvår 2024.This status report summarizes the work of National reference laboratory for air quality monitoring (NRL), subcontract 1b, for the first half year of 2024.publishedVersio
Polychlorinated alkanes in indoor environment: A review of levels, sources, exposure, and health implications for chlorinated paraffin mixtures
Get PDFPolychlorinated n-alkanes (PCAs) are the main components of chlorinated paraffins (CPs) mixtures, that have been commonly grouped into short-chain (SCCPs, C10–13), medium-chain (MCCPs, C14–17), and long-chain (LCCPs, C18-30) CPs. PCAs pose a significant risk to human health as they are broadly present in indoor environments and are potentially persistent, bioaccumulative, and toxic. The lack of specific terminology and harmonization in analytical methodologies for PCA analysis complicates direct comparisons between studies. The present work summarizes the different methodologies applied for the analysis of PCAs in indoor dust, air, and organic films. The large variability between the reviewed studies points to the difficulties to assess PCA contamination in these matrices and to mitigate risks associated with indoor exposure. Based on our review of physicochemical properties of PCAs and previously reported sum of measurable S/M/LCCPs levels, the homologue groups PCAs–C10–13 are found to be mostly present in the gas phase, PCAs–C14–17 in particulate matter and organic films, and PCAs–C≥18 in settled dust. However, we emphasized that mapping PCA sources and distribution in the indoors is highly dependent on the individual homologues. To further comprehend indoor PCA distribution, we described the uses of PCA in building materials and household products to apportion important indoor sources of emissions and pathways for human exposure. The greatest risk for indoor PCAs were estimated to arise from dermal absorption and ingestion through contact with dust and CP containing products. In addition, there are several factors affecting indoor PCA levels and exposure in different regions, including legislation, presence of specific products, cleaning routines, and ventilation frequency. This review provides comprehensive analysis of available indoor PCA data, the physicochemical properties, applied analytical methods, possible interior sources, variables affecting the levels, human exposure to PCAs, as well as need for more information, thereby providing perspectives for future research studies.publishedVersio
Two Stage Feature Engineering to Predict Air Pollutants in Urban Areas
Get PDFAir pollution is a global challenge to human health and the ecological environment. Identifying the relationship among pollutants, their fundamental sources and detrimental effects on health and mental well-being is critical in order to implement appropriate countermeasures. The way forward to address this issue and assess air quality is through accurate air pollution prediction. Such prediction can subsequently assist governing bodies in making prompt, evidence-based decisions and prevent further harm to our urban environment, public health, and climate, all of which co-benefit our economy. In this study, the main objective is to explore the strength of features and proposed a two stage feature engineering approach, which fuses the advantage of influential factors along with the decomposition approach and generates an optimum feature combination for five major pollutants including Nitrogen Dioxide (NO 2 ), Ozone (O 3 ), Sulphur Dioxide (SO 2 ), and Particulate Matter (PM2.5, and PM10). The experiments are conducted using a dataset from 2015 to 2020 which is publicly available and is collected from Belfast-based air quality monitoring stations in Northern Ireland, UK. In stage-1, using the dataset new features such as trigonometric and statistical features are created to capture their dependency on the target pollutant and generated correlation-inspired best feature combinations to improve forecasting model performance. This is further enhanced in stage-2 by an optimum feature combination which is an integration of stage-1 and Variational Mode Decomposition (VMD) based features. This study employed a simplified Long Short Term Memory (LSTM) neural network and proposed a single-step forecasting model to predict multivariate time series data. Three performance indicators are used to evaluate the effectiveness of forecasting model: (a) root mean square error (RMSE), (b) mean absolute error (MAE), and (c) R-squared (R 2 ). The results demonstrate the effectiveness of proposed approach with 13% improvement in performance (in terms of R 2 ) and the lowest error scores for both RMSE and MAE.publishedVersio
Contribution of fluorescent primary biological aerosol particles to low-level Arctic cloud residuals
Get PDFMixed-phase clouds (MPCs) are key players in the Arctic climate system due to their role in modulating solar and terrestrial radiation. Such radiative interactions rely, among other factors, on the ice content of MPCs, which is regulated by the availability of ice-nucleating particles (INPs). While it appears that INPs are associated with the presence of primary biological aerosol particles (PBAPs) in the Arctic, the nuances of the processes and patterns of INPs and their association with clouds and moisture sources have not been resolved. Here, we investigated for a full year the abundance of and variability in fluorescent PBAPs (fPBAPs) within cloud residuals, directly sampled by a multiparameter bioaerosol spectrometer coupled to a ground-based counterflow virtual impactor inlet at the Zeppelin Observatory (475 m a.s.l.) in Ny-Ålesund, Svalbard. fPBAP concentrations (10−3–10−2 L−1) and contributions to coarse-mode cloud residuals (0.1 to 1 in every 103 particles) were found to be close to those expected for high-temperature INPs. Transmission electron microscopy confirmed the presence of PBAPs, most likely bacteria, within one cloud residual sample. Seasonally, our results reveal an elevated presence of fPBAPs within cloud residuals in summer. Parallel water vapor isotope measurements point towards a link between summer clouds and regionally sourced air masses. Low-level MPCs were predominantly observed at the beginning and end of summer, and one explanation for their presence is the existence of high-temperature INPs. In this study, we present direct observational evidence that fPBAPs may play an important role in determining the phase of low-level Arctic clouds. These findings have potential implications for the future description of sources of ice nuclei given ongoing changes in the hydrological and biogeochemical cycles that will influence the PBAP flux in and towards the ArcticpublishedVersio
Evaluation of modelled versus observed non-methane volatile organic compounds at European Monitoring and Evaluation Programme sites in Europe
Get PDFAtmospheric volatile organic compounds (VOCs) constitute a wide range of species, acting as precursors to ozone and aerosol formation. Atmospheric chemistry and transport models (CTMs) are crucial to understanding the emissions, distribution, and impacts of VOCs. Given the uncertainties in VOC emissions, lack of evaluation studies, and recent changes in emissions, this work adapts the European Monitoring and Evaluation Programme Meteorological Synthesizing Centre – West (EMEP MSC-W) CTM to evaluate emission inventories in Europe. Here we undertake the first intensive model–measurement comparison of VOCs in 2 decades. The modelled surface concentrations are evaluated both spatially and temporally, using measurements from the regular EMEP monitoring network in 2018 and 2019, as well as a 2022 campaign. To achieve this, we utilised the UK National Atmospheric Emissions Inventory to derive explicit emission profiles for individual species and employed a tracer method to produce pure concentrations that are directly comparable to observations. The degree to which the modelled and measured VOCs agree varies depending on the specific species. The model successfully captures the overall spatial and temporal variations of major alkanes (e.g. ethane, n-butane) and unsaturated species (e.g. ethene, benzene) but less so for propane, i-butane, and ethyne. This discrepancy underscores potential issues in the boundary conditions for the latter species and in their primary emissions from, in particular, the solvent and road transport sectors. Specifically, potential missing propane emissions and issues with its boundary conditions are highlighted by large model underestimations and smaller propane-to-ethane ratios compared to the measurement. Meanwhile, both the model and measurements show strong linear correlations among butane isomers and among pentane isomers, indicating common sources for these pairs of isomers. However, modelled ratios of i-butane to n-butane and i-pentane to n-pentane are approximately one-third of the measured ratios, which is largely driven by significant emissions of n-butane and n-pentane from the solvent sector. This suggests issues with the speciation profile of the solvent sector, underrepresented contributions from transport and fuel evaporation sectors in current inventories, or both. Furthermore, the modelled ethene-to-ethyne and benzene-to-ethyne ratios differ significantly from measured ratios. The different model performance strongly points to shortcomings in the spatial and temporal patterns and magnitudes of ethyne emissions, especially during winter. For OVOCs, the modelled and measured concentrations of methanal and methylglyoxal show a good agreement, despite a moderate underestimation by the model in summer. This discrepancy could be attributed to an underestimation of contributions from biogenic sources or possibly a model overestimation of their photolytic loss in summer. However, the insufficiency of suitable measurements limits the evaluation of other OVOCs. Finally, model simulations employing the CAMS inventory show slightly better agreements with measurements than those using the Centre on Emission Inventories and Projections (CEIP) inventory. This enhancement is likely due to the CAMS inventory's detailed segmentation of the road transport sector, including its associated sub-sector-specific emission profiles. Given this improvement, alongside the previously mentioned concerns about the model's biased estimations of various VOC ratios, future efforts should focus on a more detailed breakdown of dominant emission sectors (e.g. solvents) and the refinement of their speciation profiles to improve model accuracy.publishedVersio
Data Fusion for Enhancing Urban Air Quality Modeling using Large-Scale Citizen Science
Get PDFRapid urbanization has led to many environmental issues, including poor air quality. With urbanization set to continue, there is an urgent need to mitigate air pollution and minimize its adverse health impacts. This study aims to advance urban air quality management by integrating a dispersion model output with large-scale citizen science data, collected over a 4-week period by 642 participants in Cork City, Ireland. The dispersion model enabled the identification of major sources of NO2 air pollution while also addressing gaps in regulatory monitoring efforts. Integrating the diffusion tube data with the dispersion model output, we developed a data fusion model that captured localized fluctuations in air quality, with increases of up to 22μg/m3 observed at major road intersections. The data fusion model provided a more accurate representation of NO2 concentrations, with estimates within 1.3μg/m3 of the regulatory monitoring measurement at an urban traffic location, an improvement of 11.7μg/m3 from the priori dispersion model. This enhanced accuracy enabled a more precise assessment of the population exposure to air pollution. The data fusion model showed a higher population exposure to NO2 compared to the dispersion model, providing valuable insights that can inform environmental health policies aimed at safeguarding public health.acceptedVersio
Widespread Pesticide Distribution in the European Atmosphere Questions their Degradability in Air
Get PDFRisk assessment of pesticide impacts on remote ecosystems makes use of model-estimated degradation in air. Recent studies suggest these degradation rates to be overestimated, questioning current pesticide regulation. Here, we investigated the concentrations of 76 pesticides in Europe at 29 rural, coastal, mountain, and polar sites during the agricultural application season. Overall, 58 pesticides were observed in the European atmosphere. Low spatial variation of 7 pesticides suggests continental-scale atmospheric dispersal. Based on concentrations in free tropospheric air and at Arctic sites, 22 pesticides were identified to be prone to long-range atmospheric transport, which included 15 substances approved for agricultural use in Europe and 7 banned ones. Comparison between concentrations at remote sites and those found at pesticide source areas suggests long atmospheric lifetimes of atrazine, cyprodinil, spiroxamine, tebuconazole, terbuthylazine, and thiacloprid. In general, our findings suggest that atmospheric transport and persistence of pesticides have been underestimated and that their risk assessment needs to be improved
New insights from an eight-year study on per- and polyfluoroalkyl substances in an urban terrestrial ecosystem
Get PDFPer- and polyfluoroalkyl substances (PFAS) were analysed in a high number of terrestrial samples of soil, earthworm, bird eggs and liver from red fox and brown rat in an urban area in Norway from 2013 to 2020. PFOS and the long chain PFCAs were the most dominating compounds in all samples, proving their ubiquitous distribution. Other less studied compounds such as 6:2 FTS were first and foremost detected in earthworm. 8:2 FTS was found in many samples of fieldfare egg, sparrowhawk egg and earthworm, where the eggs had highest concentrations. Highest concentrations for both 6:2 FTS and 8:2 FTS were detected at present and former industry areas. FOSA was detected in many samples of the species with highest concentrations in red fox liver and brown rat liver of 3.3 and 5.5 ng/g ww. PFAS concentrations from the urban area were significantly higher than from background areas indicating that some of the species can be suitable as markers for PFAS emissions in an urban environment. Fieldfare eggs had surprisingly high concentrations of PFOS and PFCA concentrations from areas known to be or have been influenced by industry. Biota-soil-accumulation factor and magnification calculations indicate accumulation and magnification potential for several PFAS. Earthworm and fieldfare egg had average concentrations above the Canadian and European thresholds in diet for avian wildlife and predators. For earthworms, 18 % of the samples exceeded the European threshold (33 ng/g ww) of PFOS in prey for predators, and for fieldfare eggs, 35 % of the samples were above the same threshold. None of the soil samples exceeded a proposed PNEC of PFOS for soil living organisms of 373 ng/g dw.publishedVersio