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2018
2018
2018
Interim Annual Assessment Report for 2017. European air quality in 2017.
Copernicus Atmosphere Monitoring Service
2018
2018
BioMed Central (BMC)
2018
Concentrations of organohalogenated contaminants (OHCs) can show significant temporal and spatial variation in the environment and wildlife. Most of the variation is due to changes in use and production, but environmental and biological factors may also contribute to the variation. Nestlings of top predators are exposed to maternally transferred OHCs in the egg and through their dietary intake after hatching. The present study investigated spatial and temporal variation of OHCs and the role of age and diet on these variations in plasma of Norwegian white-tailed eagle (Haliaeetus albicilla) nestlings. The nestlings were sampled at two locations, Smøla and Steigen, in 2015 and 2016. The age of the nestlings was recorded (range: 44 - 87 days old) and stable carbon and nitrogen isotopes (δ13C and δ15N) were applied as dietary proxies for carbon source and trophic position, respectively. In total, 14 polychlorinated biphenyls (PCBs, range: 0.82 - 59.05 ng/mL), 7 organochlorinated pesticides (OCPs, range: 0.89 - 52.19 ng/mL), 5 polybrominated diphenyl ethers (PBDEs, range: 0.03 - 2.64 ng/mL) and 8 perfluoroalkyl substances (PFASs, range: 4.58 - 52.94 ng/mL) were quantified in plasma samples from each location and year. The OHC concentrations, age and dietary proxies displayed temporal and spatial variations. The age of the nestlings was indicated as the most important predictor for OHC variation as the models displayed significantly decreasing plasma concentrations of PCBs, OCPs, and PBDEs with increasing age, while concentrations of PFASs were significantly increasing with age. Together with age, the variations in PCB, OCP and PBDE concentrations were also explained by δ13C and indicated decreasing concentrations with a more marine diet. Our findings emphasise age and diet as important factors to consider when investigating variations in plasma OHC concentrations in nestlings.
Elsevier
2018
Water column distribution of mercury species in permanently stratified aqueous environments
Biogeochemical structures of three permanently stratified waterbodies were studied: a sea water basin (the Black Sea), an estuary (Hunnbunn fjord), and a freshwater lake (Nordbytjernet), with focus on the distributions of methylmercury (MeHg) and total mercury (THg). THg concentrations were similar in the sea water basin (0.2–1.8 ng/L) and the freshwater lake (0.8–1.2 ng/L), but significantly higher in the estuary (0.6–9.4 ng/L). An increase in the MeHg concentration and MeHg/THg ratio were found in the redox zone in all three basins, indicating bacterial production of MeHg in the aqueous phase. In the lake and estuary, the maximum MeHg concentration and MeHg/THg ratio were found in samples located closest to the bottom sediments, likely due to the formation of MeHg in surface sediments and subsequent diffusion to the overlying waters.
Springer
2018
2018
2018
Model development for high-resolution emissions from residential wood combustion
In this report, we describe the MetVed model developed to estimate emissions from residential wood combustion (RWC) at high spatial-temporal resolution. The model uses a downscaling method approach, which builds on bottom-up principles and derive a wood burning potential for each grid based on the housing type, size and heating technology, energy demand and outdoor temperature of each grid. The model builds on the combination of several databases with information at high level of detail. The databases contain geo-localised information about dwelling number and type, energy consumption statistics, fireplace and stove locations, and the available technology for residential heating. The datasets are combined and the dependencies between the different variables are analysed. MetVed includes the time variation for RWC based on the heating degree concept combined with time-variation from consumer statistics, and the vertical distribution based on the RWC shared in apartment buildings versus houses. The results from the MetVed-model have shown to improve the accuracy of dispersion modelling results when compared with predictions based on previous emission inventories.
NILU
2018
In this study we apply two methods for data collection that are relatively new in the field of atmospheric science. The two developed methods are designed to collect essential geo-localized information to be used as input data for a high resolution emission inventory for residential wood combustion (RWC). The first method is a webcrawler that extracts openly online available real estate data in a systematic way, and thereafter structures them for analysis. The webcrawler reads online Norwegian real estate advertisements and it collects the geo-position of the dwellings. Dwellings are classified according to the type (e.g., apartment, detached house) they belong to and the heating systems they are equipped with. The second method is a model trained for image recognition and classification based on machine learning techniques. The images from the real estate advertisements are collected and processed to identify wood burning installations, which are automatically classified according to the three classes used in official statistics, i.e., open fireplaces, stoves produced before 1998 and stoves produced after 1998. The model recognizes and classifies the wood appliances with a precision of 81%, 85% and 91% for open fireplaces, old stoves and new stoves, respectively. Emission factors are heavily dependent on technology and this information is therefore essential for determining accurate emissions. The collected data are compared with existing information from the statistical register at county and national level in Norway. The comparison shows good agreement for the proportion of residential heating systems between the webcrawled data and the official statistics. The high resolution and level of detail of the extracted data show the value of open data to improve emission inventories. With the increased amount and availability of data, the techniques presented here add significant value to emission accuracy and potential applications should also be considered across all emission sectors.
2018
Altitude-temporal behaviour of atmospheric ozone, temperature and wind velocity observed at Svalbard
Elsevier
2018
2018