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Time trends of persistent organic pollutants (POPs) and Chemicals of Emerging Arctic Concern (CEAC) in Arctic air from 25 years of monitoring
Get PDFThe long-term time trends of atmospheric pollutants at eight Arctic monitoring stations are reported. The work was conducted under the Arctic Monitoring and Assessment Programme (AMAP) of the Arctic Council. The monitoring stations were: Alert, Canada; Zeppelin, Svalbard; Stórhöfði, Iceland; Pallas, Finland; Andøya, Norway; Villum Research Station, Greenland; Tiksi and Amderma, Russia. Persistent organic pollutants (POPs) such as α- and γ-hexachlorocyclohexane (HCH), polychlorinated biphenyls (PCBs), α-endosulfan, chlordane, dichlorodiphenyltrichloroethane (DDT) and polybrominated diphenyl ethers (PBDEs) showed declining trends in air at all stations. However, hexachlorobenzene (HCB), one of the initial twelve POPs listed in the Stockholm Convention in 2004, showed either increasing or non-changing trends at the stations. Many POPs demonstrated seasonality but the patterns were not consistent among the chemicals and stations. Some chemicals showed winter minimum and summer maximum concentrations at one station but not another, and vice versa. The ratios of chlordane isomers and DDT species showed that they were aged residues. Time trends of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) were showing decreasing concentrations at Alert, Zeppelin and Andøya. The Chemicals of Emerging Arctic Concern (CEAC) were either showing stable or increasing trends. These include methoxychlor, perfluorohexane sulfonic acid (PFHxS), 6:2 fluorotelomer alcohol, and C9-C11 perfluorocarboxylic acids (PFCAs). We have demonstrated the importance of monitoring CEAC before they are being regulated because model calculations to predict their transport mechanisms and fate cannot be made due to the lack of emission inventories. We should maintain long-term monitoring programmes with consistent data quality in order to evaluate the effectiveness of chemical control efforts taken by countries worldwide.publishedVersio
Rapport fra sammenligning av måleinstrumenter for PM10/PM2.5 i Norge, gjennomført i Oslo 2015-2016 og 2018
Get PDFThe purpose of the comparison was to test for equivalence and establish calibration functions for automatic PM-analysers commonly used in Norway. The reference laboratory performed a field test at three different locations in Oslo during summer and winter conditions in the periods September 2015 to July 2016 and February to March 2018. Participating analysers were Palas Fidas 200, Grimm EDM 180, TEI TEOM 1405 DF, TEI FH 62 I-R, and R&P TEOM 1400AB. The report proposes a system to carry out ongoing verification of equivalence in the Norwegian monitoring network and how to calibrate analyser data.Formålet med sammenligningen var å ekvivalensteste og etablere kalibreringsfaktorer for de vanligste automatiske PM-målere som er i bruk i Norge. For å etablere faktorene utførte Referanselaboratoriet en feltstudie på tre steder i Oslo under sommer- og vinterforhold i periodene september 2015 til juli 2016 og februar til mars 2018. Måleinstrumentene som deltok var Palas Fidas 200, Grimm EDM 180, TEI TEOM 1405 DF, TEI FH 62 I-R, og R&P TEOM 1400AB. Rapporten beskriver et mulig system for kontinuerlig verifikasjon av kalibreringsfaktorene i de norske målenettene og hvordan analysedata skal kalibreres.publishedVersio
Why is the city's responsibility for its air pollution often underestimated? A focus on PM2.5
Get PDFWhile the burden caused by air pollution in urban areas is well documented, the origin of this pollution and therefore the responsibility of the urban areas in generating this pollution are still a subject of scientific discussion. Source apportionment represents a useful technique to quantify the city's responsibility, but the approaches and applications are not harmonized and therefore not comparable, resulting in confusing and sometimes contradicting interpretations. In this work, we analyse how different source apportionment approaches apply to the urban scale and how their building elements and parameters are defined and set. We discuss in particular the options available in terms of indicator, receptor, source, and methodology. We show that different choices for these options lead to very large differences in terms of outcome. For the 150 large EU cities selected in our study, different choices made for the indicator, the receptor, and the source each lead to an average difference of a factor of 2 in terms of city contribution. We also show that temporal- and spatial-averaging processes applied to the air quality indicator, especially when diverging source apportionments are aggregated into a single number, lead to the favouring of strategies that target background sources while occulting actions that would be efficient in the city centre. We stress that methodological choices and assumptions most often lead to a systematic and important underestimation of the city's responsibility, with important implications. Indeed, if cities are seen as a minor actor, plans will target the background as a priority at the expense of potentially effective local actions.publishedVersio
Overvåking av langtransporterte atmosfæriske miljøgifter i luft og nedbør, årsrapport 2020.
Get PDFThis report presents environmental monitoring data from 2020 and time-trends for the Norwegian programme for Long-range atmospheric transported contaminants. The results cover 200 organic compounds (regulated and non-regulated), 11 heavy metals, and organic chemicals of potential Arctic concern.Denne rapporten inkluderer miljøovervåkningsdata fra 2020 og tidstrender for programmet Langtransporterte atmosfæriske miljøgifter. Resultatene omfatter 200 organiske miljøgifter (regulerte og ennå ikke regulerte), 11 tungmetaller og et utvalg organiske kjemikalier som potensielt er av bekymring for Arktisk miljø.publishedVersio
Fluorescent Nanocomposites: Hollow Silica Microspheres with Embedded Carbon Dots
Get PDFIntrinsically fluorescent carbon dots may form the basis for a safer and more accurate sensor technology for digital counting in bioanalytical assays. This work presents a simple and inexpensive synthesis method for producing fluorescent carbon dots embedded in hollow silica particles. Hydrothermal treatment at low temperature (160 °C) of microporous silica particles in presence of urea and citric acid results in fluorescent, microporous and hollow nanocomposites with a surface area of 12 m2/g. High absolute zeta potential (−44 mV) at neutral pH demonstrates the high electrosteric stability of the nanocomposites in aqueous solution. Their fluorescence emission at 445 nm is remarkably stable in aqueous dispersion under a wide pH range (3–12) and in the dried state. The biocompatibility of the composite particles is excellent, as the particles were found to show low genotoxicity at exposures up to 10 μg/cm2.publishedVersio
Mikrosensorer og målenett
Get PDFThe increase of the commercial availability of low-cost sensor technology to monitor atmospheric composition is contributing to the rapid adoption of such technology by both public authorities and self-organized initiatives (e.g. grass root movements, citizen science, etc.). Low-cost sensors (LCS) can provide real time measurements, in principle at lower cost than traditional monitoring reference stations, allowing higher spatial coverage than the current reference methods. However, data quality from LCS is lower than the one provided by reference methods. Also, the total cost of deploying a dense sensor network needs to consider the costs associated not only to the sensor platforms but also the costs associated for instance with deployment, maintenance and data transmission. This report aims to give an overview of the current status of LCS technology in relation to commercialization, measuring capabilities and data quality, with especial emphasis on the challenges associated to the use of this novel technology, and the opportunities they open when correctly used.Denne rapporten går igjennom status innen mikrosensorteknologien. Den vurderer tilgjengelighet av produkter på markedet, målte parametere og datakvalitet, samt hvilke muligheter sensorene åpner for når de blir brukt riktig.publishedVersio
Air quality monitoring in the border areas of Norway and Russia, annual report 2020
Get PDFSmelteverkene i nordvest-Russland slapp ut store mengder svoveldioksid (SO2) og tungmetaller. Utslippene påvirket luft- og nedbørkvalitet i grenseområdene. Miljøovervåkingen viser at grenseverdier for SO2 er overholdt i kalenderåret 2020, samt for vinter 2019/20. Smelteverket i Nikel stengte ned 23. desember 2020 og dette er ventet å gi stor nedgang i forurensningen i grenseområdene. Målsettingsverdier for Ni, As og Cd er overholdt.The nickel smelters in northwest-Russia emitted large quantities of sulphur dioxide (SO2) and heavy metals. These emissions lead to enhanced concentrations of environmental pollutants in the border areas. The monitoring programme shows that air quality in the border areas was in compliance with Norwegian critical levels for SO2 for the calendar year 2020, as well as for seasonal mean for the winter 2019/20. The smelter in Nikel ceased operation on 23 December 2020. This will give less pollution in the border areas in the future. Target values for Ni, As and Cd were not exceeded.publishedVersio
Differentiation of coarse-mode anthropogenic, marine and dust particles in the High Arctic islands of Svalbard
Get PDFUnderstanding aerosol–cloud–climate interactions in the Arctic is key to predicting the climate in this rapidly changing region. Whilst many studies have focused on submicrometer aerosol (diameter less than 1 µm), relatively little is known about the supermicrometer aerosol (diameter above 1 µm). Here, we present a cluster analysis of multiyear (2015–2019) aerodynamic volume size distributions, with diameter ranging from 0.5 to 20 µm, measured continuously at the Gruvebadet Observatory in the Svalbard archipelago. Together with aerosol chemical composition data from several online and offline measurements, we apportioned the occurrence of the coarse-mode aerosols during the study period (mainly from March to October) to anthropogenic (two sources, 27 %) and natural (three sources, 73 %) origins. Specifically, two clusters are related to Arctic haze with high levels of black carbon, sulfate and accumulation mode (0.1–1 µm) aerosol. The first cluster (9 %) is attributed to ammonium sulfate-rich Arctic haze particles, whereas the second one (18 %) is attributed to larger-mode aerosol mixed with sea salt. The three natural aerosol clusters were open-ocean sea spray aerosol (34 %), mineral dust (7 %) and an unidentified source of sea spray-related aerosol (32 %). The results suggest that sea-spray-related aerosol in polar regions may be more complex than previously thought due to short- and long-distance origins and mixtures with Arctic haze, biogenic and likely blowing snow aerosols. Studying supermicrometer natural aerosol in the Arctic is imperative for understanding the impacts of changing natural processes on Arctic aerosol.publishedVersio
Knowledge architecture for the wise governance of sustainability transitions
Get PDFThe need for sustainability transitions is widely recognised, along with a concurrent need for the evolution of knowledge systems to inform more effective policy action. Although there are many new policy targets relating to net zero emissions and other sustainability challenges, cities, regional and national governments are struggling to rapidly develop transformational policies to achieve them. As academics and practitioners who work at the science-policy interface, we identify specific knowledge and competency needs for governing sustainability transitions related to the interlinked phases of envisioning, implementing and evaluating. In short, coordinated reforms of both policy and knowledge systems are urgently needed to address the speed and scale of sustainability challenges. These include embedding systems thinking literacy, mainstreaming participatory policy making, expanding the capacity to undertake transdisciplinary research, more adaptive governance and continuous organisational learning. These processes must guide further knowledge development, uptake and use as part of an iterative and holistic process. Such deep-seated change in policy-knowledge systems will be disruptive and presents challenges for traditional organisational models of knowledge delivery, but is essential for successful sustainability transformations.publishedVersio
Eastward-Propagating Planetary Waves Prior to the January 2009 Sudden Stratospheric Warming
Get PDFEastward-propagating planetary waves (EPWs) were investigated prior to the boreal January 2009 major sudden stratospheric warming (SSW) event simulated by the National Center for Atmospheric Research's Whole Atmosphere Community Climate Model with specified dynamics. About 22 days before SSW onset, a background flow with jet maxima around the upper polar stratosphere and subtropical mesosphere developed due to the net forcing by gravity and planetary waves. The mesospheric wind structure was largely unstable and supported a wave geometry conducive to overreflection. With a zonal phase speed of ∼10 m s−1, EPWs appeared near their turning and critical layers as wavenumber-2 perturbations in the stratosphere and mesosphere. Accompanied by upward EPW activity from the lower stratosphere, EPW growth exhibited characteristics of wave instability and overreflection.publishedVersio