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2021
2021
Atmospheric composition in the European Arctic and 30 years of the Zeppelin Observatory, Ny-Ålesund,
2021
Reliable quantification of the sources and sinks of greenhouse gases, together with trends and uncertainties, is essential to monitoring the progress in mitigating anthropogenic emissions under the Paris Agreement. This study provides a consolidated synthesis of CH4 and N2O emissions with consistently derived state-of-the-art bottom-up (BU) and top-down (TD) data sources for the European Union and UK (EU27 + UK). We integrate recent emission inventory data, ecosystem process-based model results and inverse modeling estimates over the period 1990–2017. BU and TD products are compared with European national greenhouse gas inventories (NGHGIs) reported to the UN climate convention UNFCCC secretariat in 2019. For uncertainties, we used for NGHGIs the standard deviation obtained by varying parameters of inventory calculations, reported by the member states (MSs) following the recommendations of the IPCC Guidelines. For atmospheric inversion models (TD) or other inventory datasets (BU), we defined uncertainties from the spread between different model estimates or model-specific uncertainties when reported. In comparing NGHGIs with other approaches, a key source of bias is the activities included, e.g., anthropogenic versus anthropogenic plus natural fluxes. In inversions, the separation between anthropogenic and natural emissions is sensitive to the geospatial prior distribution of emissions. Over the 2011–2015 period, which is the common denominator of data availability between all sources, the anthropogenic BU approaches are directly comparable, reporting mean emissions of 20.8 Tg CH4 yr−1 (EDGAR v5.0) and 19.0 Tg CH4 yr−1 (GAINS), consistent with the NGHGI estimates of 18.9 ± 1.7 Tg CH4 yr−1. The estimates of TD total inversions give higher emission estimates, as they also include natural emissions. Over the same period regional TD inversions with higher-resolution atmospheric transport models give a mean emission of 28.8 Tg CH4 yr−1. Coarser-resolution global TD inversions are consistent with regional TD inversions, for global inversions with GOSAT satellite data (23.3 Tg CH4 yr−1) and surface network (24.4 Tg CH4 yr−1). The magnitude of natural peatland emissions from the JSBACH–HIMMELI model, natural rivers and lakes emissions, and geological sources together account for the gap between NGHGIs and inversions and account for 5.2 Tg CH4 yr−1. For N2O emissions, over the 2011–2015 period, both BU approaches (EDGAR v5.0 and GAINS) give a mean value of anthropogenic emissions of 0.8 and 0.9 Tg N2O yr−1, respectively, agreeing with the NGHGI data (0.9 ± 0.6 Tg N2O yr−1). Over the same period, the average of the three total TD global and regional inversions was 1.3 ± 0.4 and 1.3 ± 0.1 Tg N2O yr−1, respectively. The TD and BU comparison method defined in this study can be operationalized for future yearly updates for the calculation of CH4 and N2O budgets both at the EU+UK scale and at the national scale. The referenced datasets related to figures are visualized at https://doi.org/10.5281/zenodo.4590875 (Petrescu et al., 2020b)
2021
The historical (1835–2020) deposition of major air pollutants (SO2, NOx, O3 and PM2.5) indoors, as represented by the monumental Edvard Munch paintings (c. 220 m2) installed in 1916 in the Oslo University Aula in Norway, were approximated from the outdoor air concentrations, indoor to outdoor concentration ratios and dry deposition velocities. The annual deposition of the pollutants to the paintings was found to have been 4–25 times lower than has been reported to buildings outdoors in the urban background in the centre of Oslo. It reflected the outdoor deposition but varied less, from 0.3 to 1.2 g m−2 a−1. The accumulated deposition since 1916, and then not considering the regularly performed cleaning of the paintings, was found to have been 43 ± 13 g m−2, and 110 ± 40 g m−2 in a similar situation since 1835. The ozone deposition, and the PM2.5 deposition before the 1960s, were a relatively larger part of the accumulated total indoor (to the paintings) than reported outdoor deposition. About 18 and 33 times more O3 than NOx and PM2.5 deposition was estimated to the paintings in 2020, as compared to the about similar reported outdoor dry deposition of O3 and NOx. The deposition of PM2.5 to the paintings was probably reduced with about 62% (50–80%) after installation of mechanical filtration in 1975 and was estimated to be 0.011 (± 0.006) g m−2 in 2020.
2022
2022
Monitoring of the atmospheric ozone layer and natural ultraviolet radiation. Annual report 2021.
This report summarizes the results from the Norwegian monitoring programme on stratospheric ozone and UV radiation measurements. The ozone layer has been measured at three locations since 1979: In Oslo/Kjeller, Tromsø/Andøya and Ny-Ålesund. The UV-measurements started in 1995. The results show that there was a significant decrease in stratospheric ozone above Norway between 1979 and 1997. After that, the ozone layer stabilized at a level ~2% below pre-1980 level. The year 2021 was characterized by low total ozone values in June and July, whereas “normal” ozone values were measured during winter and spring.
NILU
2022
Clean air policies are key for successfully mitigating Arctic warming
A tighter integration of modeling frameworks for climate and air quality is urgently needed to assess the impacts of clean air policies on future Arctic and global climate. We combined a new model emulator and comprehensive emissions scenarios for air pollutants and greenhouse gases to assess climate and human health co-benefits of emissions reductions. Fossil fuel use is projected to rapidly decline in an increasingly sustainable world, resulting in far-reaching air quality benefits. Despite human health benefits, reductions in sulfur emissions in a more sustainable world could enhance Arctic warming by 0.8 °C in 2050 relative to the 1995–2014, thereby offsetting climate benefits of greenhouse gas reductions. Targeted and technically feasible emissions reduction opportunities exist for achieving simultaneous climate and human health co-benefits. It would be particularly beneficial to unlock a newly identified mitigation potential for carbon particulate matter, yielding Arctic climate benefits equivalent to those from carbon dioxide reductions by 2050.
2022
2022
On behalf of Aluminiumindustriens Miljøsekretariat (AMS), NILU – Norwegian Institute for Air Research reviewed existing data on ambient air quality around aluminium smelters from the period 1992 – 2020. Changes in production technologies and treatment technologies have been implemented in this time period. Emissions to air and ambient concentrations of most compounds typically measured (PAHs, fluorides, sulphur dioxide, particulate matter, heavy metals) have decreased since the beginning of the 1990s as a result of improvement of the production technology.
NILU
2022
2022
Frontiers Media S.A.
2022
Numerical Study of Non-Linear Effects for a Swept Bias Langmuir Probe
We present a numerical study disclosing non-linear effects and hysteresis loops for a swept bias Langmuir probe. A full kinetic particle in cell (PIC) model has been used to study the temporal sheath effects and the probe current. Langmuir "close to steady state" condition is required to characterize the plasma. However, during operations above frequencies normally used, capacitive and non-linear resistive effects are being unveiled. We demonstrate how ion and electron density and temperature change properties of the probe-plasma system. We also show that a swept Langmuir probe exhibits essential properties described as the "fingerprint of memristors" and how a Langmuir probe can be identified as a transversal memristor. Understanding non-linear processes might enable new ways to operate Langmuir probes with higher sampling rates and better accuracy.
2022
2022
2022
2022
Hazard identification and safety assessment of the huge variety of nanomaterials (NMs), calls for robust and validated toxicity screening tests in combination with cheminformatics approaches to identify factors that can drive toxicity. Cytotoxicity and genotoxicity of seventeen JRC repository NMs, derived from titanium dioxide, zinc oxide, silver and silica, were tested in vitro using human lung alveolar epithelial cells A549. Cytotoxicity was assessed with the AlamarBlue (AB) and colony forming efficiency (CFE) assays, and genotoxicity by the enzyme-linked version of the comet assay. Nanoparticle tracking analysis (NTA) was used to measure size of the NMs in stock and in cell culture medium at different time points. Categorization and ranking of cytotoxic and genotoxic potential were performed (EU-NanoREG2 project approach). Descriptors for prediction of NMs toxicity were identified by quantitative structure-activity relationship (QSAR) analysis. Our results showed that ZnO NMs (NM-110 and NM-111), and Ag NMs (NM-300K and NM-302) were cytotoxic, while the TiO2 and SiO2 NMs were non-cytotoxic. Regarding genotoxicity, TiO2 NM-100, ZnO NM-110, SiO2 NM-203 and Ag NM-300K were categorized as positive. Cheminformatics modeling identified electron properties and overall chemical reactivity as important descriptors for cytotoxic potential, HOMO-LUMO energy parameter, ionization potential, pristine size for the NMs´ genotoxic potential, and presence of surface coating as descriptor for induction of DNA oxidized base lesions.
2022
2022
Plastic burdens in northern fulmars from Svalbard: looking back 25 years
The northern fulmar Fulmarus glacialis ingests a larger number of (micro)plastics than many other seabirds due to its feeding habits and gut morphology. Since 2002, they are bioindicators of marine plastics in the North Sea region, and data are needed to extend the programme to other parts of their distribution areas, such as the Arctic. In this study, we provide data on ingested plastics by fulmars collected in 1997 in Kongsfjorden, Svalbard. An extraction protocol with KOH was used and for half of the birds, the gizzard and the proventricular contents were analysed separately. Ninety-one percent of the birds had ingested at least one piece of plastic with an average of 10.3 (±11.9 SD) pieces. The gizzards contained significantly more plastics than the proventriculus. Hard fragments and polyethylene were the most common characteristics. Twelve percent of the birds exceeded the EcoQO value of 0.1 g.
2022