Rapport

National Mercury Assessment – An Evaluation of the Effectiveness of Norwegian Mercury Regulations and Policies

Braaten, Hans Fredrik Veiteberg; Pfaffhuber, Katrine Aspmo; Routti, Heli Anna Irmeli; Knutsen, Helle Katrine; Bank, Michael; Travnikov, Oleg; Enge, Caroline; Gundersen, Cathrine Brecke; Eckhardt, Sabine; Tørseth, Kjetil; Vejrup, Kristine; Brantsæter, Anne Lise

The National Mercury (Hg) Assessment in Norway evaluates the connections among: (a) national, regional and global Hg policies and regulations, (b) emissions, releases, uses and exposure pathways of Hg, and (c) concentrations of Hg in the environment, biota, and humans, measured during 2000-2020. Our findings suggest that the key changes of Hg in humans and the environment are highly dependent on the quality of the datasets, yet connections both to national and regional sources, as well as climate related drivers could be made for some data sets.

Norwegian Environment Agency

Monitoring of the atmospheric ozone layer and natural ultraviolet radiation. Annual report 2021.

Svendby, Tove Marit; Hansen, Georg H.; Bernet, Leonie; Bäcklund, Are; Nilsen, Anne-Cathrine; Schulze, Dorothea; Johnsen, Bjørn

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

Integrated assessment of noise and air quality in European cities. Methodology.

Peris, Eulàlia; Öztürk, Evrim Dogan; Gsella, Artur; Blanes, Núria; Sáinz de la Maza, Miquel; Domingues, Francisco; Soares, Joana; Guerreiro, Cristina; Horálek, Jan

The resulting index provides spatial information on the areas most affected combining noise and air pollution across European urban areas. This information can build on and contribute to the EEA’s integrated assessments and it is going to be used to disseminate information on the European environment to policy makers and to European citizens.

ETC/ATNI

Revising PM2.5 emissions from residential combustion, 2005–2019. Implications for air quality concentrations and trends.

Simpson, David; Kuenen, Jeroen; Fagerli, Hilde; Heinesen, Daniel; Benedictow, Anna Maria Katarina; Denier van der Gon, Hugo A.C.; Visschedijk, Antoon; Klimont, Zbigniew; Aas, Wenche; Lin, Yong; Yttri, Karl Espen; Paunu, Ville-Veikko

Condensable primary organic aerosol (CPOA) emissions are a class of organic compounds that are vapour phase at stack conditions, but which can undergo both condensation and evaporation processes as the stack air is cooled and diluted upon discharge into ambient air. Emission factors may misrepresent, and even miss, the amount of particulate matter (PM) or gas that actually enters the atmosphere, depending on the emission measurement techniques used. In the current emission reporting to EMEP/CLRTAP there is no clear definition of whether condensable organics are included or not, and, if included, to what extent.

In this study, new residential combustion emission estimates have been made for the years 2005-2019 (called TNO Ref2_v2.1) in a consistent manner, with improved estimation of fuel consumption (in particular wood) and emission factors, as well as an updated split of fuel use over different appliances and technologies. For these two elements, data were taken primarily from the Eurostat fuel statistics and the IIASA GAINS model. Three scenarios have been defined: a “typical” case, which is our best estimate, an alternative “ideal” case which excludes the impact of “bad combustion”, and a “high EF” scenario in which higher emission factors are assumed than in the typical scenario. Total emissions in the typical scenario are around 40% higher than in the ideal case (in 2019), whereas resulting emissions in the “high EF” scenario are around 90% higher than in the typical scenario.

The Ref2_v2.1 inventory was used in a series of modelling studies which aimed to assess the importance of condensable organics for current air quality, for trends over time (2010–2019), and for source-receptor calculations.

Including condensables in a consistent way for all countries gave model results (concentrations, trends and bias) in better agreement with observations for OC and PM2.5 than when using the EMEP emissions which have condensables for some countries but not others. However, the model results were sensitive to the choice of Ref2_v2.1 scenario, and also to the assumptions concerning volatility of the CPOA emissions, and assumptions about extra intermediate-volatility volatile organic compounds (IVOC) associated with such emissions.

No single setup performed best for each site. There are many factors that can contribute to such mixed results (activity data, emissions factors, assumed combustion conditions, large and small scale spatial distributions issues in emissions, dispersion and CPOA/IVOC assumptions in the modelling), and much further work (and with other observational data-sets) will be needed to disentangle the reasons for model-measurement discrepancies, and to draw conclusions on how realistic the new emissions are.

Assumptions about volatility seem to be important for both the country-to-itself contribution, and for impacts of each country on others. In the few cases investigated so far, assuming inert CPOA provides results which generally lie within the range of the more complex VBS scenarios. Given the many uncertainties associated with the emissions and the modelling of POA and SOA, these results indicates that the inert CPOA assumptions provide a reasonable first approach for handling POA emissions, which can hopefully be improved once our understanding of the sources and processing of these compounds improves.

The new emission data-base, combined with increasing availability of measurements of organic and other components, should provide the best available basis for future improvements in both the emission inventories and model formulations. Much analysis and further tests remain, both with the other model setups, and ideally with alternative secondary organic aerosol schemes to get a better idea of the sensitivity of the results to the various assumptions concerning both emissions and atmospheric processing of POA.

Nordic Council of Ministers

Re-evaluation and Homogenization of Aerosol Optical Depth Observations in Svalbard (ReHearsol). RCN Project No: 311250/E40 - ReHearsol Final Report

Hansen, Georg H.; Zielinski, Tymon; Pakszys, Paulina; Ritter, Christoph; Gilardoni, Stefania; Eleftheriadis, Konstantinos; Kouremeti, Natalia; Mateos, David; Herrero, Sara; Kazadzis, Stelios; Mazzola, Mauro; Stebel, Kerstin

The aim of this project was to collect, integrate and analyse observations of climate-relevant aerosol parameters (aerosol optical depth (AOD), Ångstrøm exponent (AE), black carbon (BC)) in and around Svalbard. These observations have been performed at different places and with different instrument types, the analysis procedures of which follow different protocols. Annual merged datasets of AOD, AE and BC have been provided to the SIOS Data Management System and are now available for network-wide use in, e.g., Arctic climate and pollution studies. The analysis of the 2002-2020 data have confirmed earlier results showing a good correlation between measurements in Ny-Ålesund and Hornsund, but not a high degree of short-term agreement due to aerosol variability arising from geographical locations and local conditions. There is also a clear link between the columnar AOD/AE-measurements and in-situ aerosol measurements at Gruvebadet Observatory, while a comparison of in-situ measurements at Gruvebadet and Zeppelin Observatory shows deviations varying with season.

NILU