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2019
2019
Europe's urban air quality — re-assessing implementation challenges in cities
This report analyses the implementation of EU air quality legislation at the urban level and identifies some of the reasons behind persistent air quality problems in Europe's cities. It is produced in cooperation with 10 cities involved in a 2013 Air Implementation Pilot project: Antwerp (Belgium), Berlin (Germany), Dublin (Ireland), Madrid (Spain), Malmö (Sweden), Milan (Italy), Paris (France), Plovdiv (Bulgaria), Prague (Czechia) and Vienna (Austria).
European Environment Agency
2019
2019
Two years of continuous in situ measurements of Arctic low‐level clouds have been made at the Mount Zeppelin Observatory (78°56′N, 11°53′E), in Ny‐Ålesund, Spitsbergen. The monthly median value of the cloud particle number concentration (Nc) showed a clear seasonal variation: Its maximum appeared in May–July (65 ± 8 cm−3), and it remained low between October and March (8 ± 7 cm−3). At temperatures warmer than 0 °C, a clear correlation was found between the hourly Nc values and the number concentrations of aerosols with dry diameters larger than 70 nm (N70), which are proxies for cloud condensation nuclei (CCN). When clouds were detected at temperatures colder than 0 °C, some of the data followed the summertime Nc to N70 relationship, while other data showed systematically lower Nc values. The lidar‐derived depolarization ratios suggested that the former (CCN‐controlled) and latter (CCN‐uncontrolled) data generally corresponded to clouds consisting of supercooled water droplets and those containing ice particles, respectively. The CCN‐controlled data persistently appeared throughout the year at Zeppelin. The aerosol‐cloud interaction index (ACI = dlnNc/(3dlnN70)) for the CCN‐controlled data showed high sensitivities to aerosols both in the summer (clean air) and winter–spring (Arctic haze) seasons (0.22 ± 0.03 and 0.25 ± 0.02, respectively). The air parcel model calculations generally reproduced these values. The threshold diameters of aerosol activation (Dact), which account for the Nc of the CCN‐controlled data, were as low as 30–50 nm when N70 was less than 30 cm−3, suggesting that new particle formation can affect Arctic cloud microphysics.
2019
2019
2019
Air quality assessment and management in Europe and Norway: History, current status and future plans
2019
2019
2019
2019
Norwegian Scientific Committee for Food and Environment (VKM)
2019
Målet med studien er å vurdere effekten av tilskudd til utskifting av gamle vedovner til nye rentbrennende ovner, og i hvilken grad ordningen har påvirket det totale partikkelutslippet og luftkonsentrasjoner i Oslo kommune. NILU har utført tre beregninger; 1) utslippsmodellering og spredningsberegninger for 4 ulike scenarioer; 2) utslippsreduksjon fra tilskuddsordningen i Oslo kommune; og 3) vurdering av tidsutvikling av vedfyringsutslipp, vedforbruk og utslippsfaktorer for kommuner med og uten tilskuddsordning. Modellering og vurdering av den potensielle utslippsreduksjonen som kan tilskrives tilskuddsordningen, viser at tilskuddsordningen potensielt har en stor effekt på reduksjon av partikkelutslipp og konsentrasjoner av PM2.5 og PM10. Beregnigene viser at tilskuddsordningen i Oslo kommune gir betydelig redusert utslippsfaktor over tid, men effekten på totalt PM-utslipp er liten.
NILU
2019
Anodes fabricated from a single source coke were used for investigations of effect of porosity and surface roughness on the electrochemical performance in laboratory scale cells. In order to fabricate anodes differing in porosity, the production parameters were varied with two levels of mixing temperatures (150 and 210 °C) and three baking levels (underbaking at 1150°E, normal baking at 1260°E, overbaking at 1350°E). °E denotes the equivalent temperature which is a function of both the temperature the anode sees, and the time kept at this temperature. The low mixing anodes were more inhomogeneous with respect to both micro- and macroporosity, which can be attributed to the wetting between pitch and coke. After electrolysis, the real surface area of the low mixing anodes was about 13% higher than the high mixing anodes. Also, the low mixing electrodes had slightly larger electrochemically active surface area after electrolysis compared to the high mixing electrodes, as evidenced by higher capacitance measured at low current densities. Still, the mixing and equivalent baking temperatures did not affect the electrochemical overpotential at 1 A/cm2 to any significant extent. This could be understood from the 3D computed tomography images, which also showed that the electrolyte does not generally penetrate into the pores on the surface, penetration will depend on the size and shape of the pore.
2019
DNA double‐strand breaks in Arctic char (Salvelinus alpinus) from Bjørnøya in the Norwegian Arctic
High levels of organochlorine contaminants (OCs) have been found in arctic char (Salvelinus alpinus) from Lake Ellasjøen, Bjørnøya (Norwegian Arctic). The aim of the present study was to investigate the potential genotoxic effect of environmental organochlorine contaminant exposure in arctic char from Ellasjøen compared with arctic char from the low‐contaminated Lake Laksvatn nearby. Blood was analyzed using agarose gel electrophoresis and image data analysis to quantify the fraction of total DNA that migrated into the gel (DNA‐FTM) as a relative measure of DNA double‐strand breaks (DSBs). Analysis by GC‐MS of muscle samples showed an average 43 times higher concentration of ΣOCs in arctic char from Ellasjøen (n = 18) compared with Laksvatn char (n = 21). Char from Lake Ellasjøen had a much higher frequency of DSBs, as measured by DNA‐FTM, than char from Lake Laksvatn. Principal component analysis and multiple linear regressions show that there was a significant positive relationship between DSBs and levels of organochlorine contaminants in the char. In addition, DSBs were less frequent in reproductively mature char than in immature char. The results suggest that organochlorine contaminants are genotoxic to arctic char.
2019
Snow initialization has been previously investigated as a potential source of predictability atthe subseasonal‐to‐seasonal (S2S) timescale in winter and spring, through its local radiative,thermodynamical, and hydrological feedbacks. However, previous studies were conducted with low‐topmodels over short periods only. Furthermore, the potential role of the land surface‐stratosphere connectionupon the S2S predictability had remained unclear. To this end, we have carried out twin 30‐memberensembles of 2‐month (November and December) retrospective forecasts over the period 1985–2016, witheither realistic or degraded snow initialization. A high‐top version of the Norwegian Climate PredictionModel is used, based on the Whole Atmosphere Community Climate Model, to insure improved couplingwith the stratosphere. In a composite difference of high versus low initial Eurasian snow, the surfacetemperature is strongly impacted by the presence of snow, and wave activityfluxes into the stratosphere areenhanced at a 1‐month lag, leading to a weakened polar vortex. Focusing further on 7 years characterized bya strongly negative phase of the Arctic Oscillation, wefind a weak snow feedback contributing to themaintenance of the negative Arctic Oscillation. By comparing the twin forecasts, we extracted the predictiveskill increment due to realistic snow initialization. The prediction of snow itself is greatly improved, andthere is increased skill in surface temperature over snow‐covered land in thefirst 10 days, and localized skillincrements in the mid‐latitude transition regions on the southernflanks of the snow‐covered land areas, atlead times longer than 30 days.
2019
Eggs of snow buntings (Plectrophenax nivealis) were applied as a bio-indicator to examine differences in exposure to legacy persistent organic pollutants (POPs) and perflouroalkyl subtances (PFAS) from the terrestrial environment surrounding the settlements of Longyearbyen, Barentsburg and Pyramiden on Svalbard, Norway. Significantly higher concentrations of summed polychlorinated biphenyls (sumPCB7) in eggs collected from Barentsburg (2980 ng/g lipid weight (lw)) and Pyramiden (3860 ng/g lw) compared to Longyearbyen (96 ng/g lw) are attributed to local sources of PCBs within these settlements. Similar findings were observed for p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE) where higher median concentrations observed in Pyramiden (173 ng/g lw) and Barentsburg (75 ng/g lw) compared to Longyearbyen (48 ng/g lw) may be influenced by guano inputs from breeding seabird populations, although other point sources cannot be ruled out. Concentrations of perfluorooctane sulphonate (PFOS) and several perfluorinated carboxylic acids (PFCAs) in snow bunting eggs were found to be statistically higher in the populated settlements of Longyearbyen and Barentsburg compared to the abandoned Pyramiden. Narrow foraging ranges of snow buntings during breeding season was useful in assessing point sources of exposure for PCBs and PFAS at particular sites with extreme differences observed between nest locations. SumPCB7 concentrations ranged from 2 μg/g ww to below detection limits between nest sites located less than a kilometer from each other in Pyramiden. Similar findings were observed in Longyearbyen, where several PFCAs ranged from 2 to 55 times higher between nest sites with similar spatial distances. These findings indicate that snow buntings can be a useful bio-indicator offering high spatial resolution for contaminant source apportionment in terrestrial environments on Svalbard.
2019