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Relative impacts of sea ice loss and atmospheric internal variability on winter Arctic to East Asian surface air temperature based on large-ensemble simulations with NorESM2

He, Shengping; Drange, Helge; Furevik, Tore; Wang, Hui-Jun; Fan, Ke; Graff, Lise Seland; Orsolini, Yvan Joseph Georges Emile G.

Science Press


Challenges in using EO to characterise vegetation fires in the Global Fire Assimilation System of CAMS

Kaiser, Johannes W; Stebel, Kerstin; Tørseth, Kjetil; Parrington, Mark; Di Tomaso, Enza


Interpolation, Satellite-Based Machine Learning, or Meteorological Simulation? A Comparison Analysis for Spatio-temporal Mapping of Mesoscale Urban Air Temperature

Hassani, Amirhossein; Sousa Santos, Gabriela; Schneider, Philipp; Castell, Nuria

Fine-resolution spatio-temporal maps of near-surface urban air temperature (Ta) provide crucial data inputs for sustainable urban decision-making, personal heat exposure, and climate-relevant epidemiological studies. The recent availability of IoT weather station data allows for high-resolution urban Ta mapping using approaches such as interpolation techniques or machine learning (ML). This study is aimed at executing these approaches and traditional numerical modeling within a practical and operational framework and evaluate their practicality and efficiency in cases where data availability, computational constraints, or specialized expertise pose challenges. We employ Netatmo crowd-sourced weather station data and three geospatial mapping approaches: (1) Ordinary Kriging, (2) statistical ML model (using predictors primarily derived from Earth Observation Data), and (3) weather research and forecasting model (WRF) to predict/map daily Ta at nearly 1-km spatial resolution in Warsaw (Poland) for June–September and compare the predictions against observations from 5 meteorological reference stations. The results reveal that ML can serve as a viable alternative approach to traditional kriging and numerical simulation, characterized by reduced complexity and higher computational speeds within the domain of urban meteorological studies (overall RMSE = 1.06 °C and R2 = 0.94, compared to ground-based meteorological stations). The results have implications for identifying the urban regions vulnerable to overheating and evidence-based urban management in response to climate change. Due to the open-sourced nature of the applied predictors and input parsimony, the ML method can be easily replicated for other EU cities.


Atmospheric Microplastic in the Arctic and the Norwegian mainland

Herzke, Dorte; Evangeliou, Nikolaos; Bjørnsen, Astrid E.; Eckhardt, Sabine


Impacts of a warming climate on concentrations of organochlorines in a fasting high arctic marine bird: Direct vs. indirect effects?

Bustnes, Jan Ove; Bårdsen, Bård-Jørgen; Moe, Børge; Herzke, Dorte; Ballesteros, Manuel; Fenstad, Anette; Borgå, Katrine; Krogseth, Ingjerd Sunde; Eulaers, Igor; Skogeng, Lovise Pedersen; Gabrielsen, Geir Wing; Hanssen, Sveinn Are

The present study examined how climate changes may impact the concentrations of lipophilic organochlorines (OCs) in the blood of fasting High Arctic common eiders (Somateria mollissima) during incubation. Polychlorinated biphenyls (PCBs), 1-dichloro-2,2-bis (p-chlorophenyl) ethylene (p,p′-DDE), hexachlorobenzene (HCB) and four chlordane compounds (oxychlordane, trans-chlordane and trans- and cis-nonachlor) were measured in females at chick hatching (n = 223) over 11 years (2007–2017). Firstly, median HCB and p,p′-DDE concentrations increased ~75 % over the study period, whereas median chlordane concentrations doubled (except for oxychlordane). PCB concentrations, in contrast, remained stable over the study period. Secondly, both body mass and clutch size were negatively associated with OC levels, suggesting that females with high lipid metabolism redistributed more OCs from adipose tissue, and that egg production is an important elimination route for OCs. Thirdly, the direct climate effects were assessed using the mean effective temperature (ET: air temperature and wind speed) during incubation, and we hypothesized that a low ET would increase redistribution of OCs. Contrary to expectation, the ET was positively correlated to most OCs, suggesting that a warmer climate may lead to higher OCs levels, and that the impact of ET may not be direct. Finally, potential indirect impacts were examined using the Arctic Oscillation (AO) in the three preceding winters (AOwinter 1–3) as a proxy for potential long-range transport of OCs, and for local spring climate conditions. In addition, we used chlorophyll a (Chla) as a measure of spring primary production. There were negative associations between AOwinter 1 and HCB, trans-chlordane and trans-nonachlor, whereas oxychlordane and cis-chlordane were negatively associated with Chla. This suggests that potential indirect climate effects on eiders were manifested through the food chain and not through increased long-range transport, although these relationships were relatively weak.



Uptake of organic contaminants from car tire microplastics in Arctic marine species

Halsband, Claudia; Hägg, Fanny; Galtung, Kristin; Herzke, Dorte; Nikiforov, Vladimir; Sperre, Kristine Hopland; Sørensen, Lisbet; Egeness, Mari Jystad; Booth, Andy

Car tire particles represent an important environmental challenge that is difficult to alleviate. The particles stem from abrasion during driving, so-called tire wear particles (TWPs), down-cycled end-oflife tire crumb rubber (CR) granulate that is used widely as low-cost infill on sports fields, or degradation products from discarded tires. The material contains a variety of additives and chemical residues from the manufacturing process, including metals, especially high concentrations of zinc, polycyclic aromatic hydrocarbons (PAHs), and benzothiazoles (Halsband et al., 2020), but also paraphenylenediaminesb (PPDs) and numerous other organic chemicals. In urbanized areas, TWPs arebemitted from vehicles, while CR is dispersed from artificial sports fields and other urban surfaces to the environment. This suggests that particulate and chemical runoff to coastal systems is likely and represents a route of exposure to marine organisms. In the Arctic, even small human settlements can represent local sources of TWPs and CR granulate emissions. Here, we summarize recent experimental studies examining the responses of different marine animals to tire rubber particle or leachate exposure, focusing on toxicity and the uptake kinetics of tire-related organic chemicals into organs and tissues. We present data for different ecological functional groups relevant to the Arctic, including copepods, shrimps, crabs, and fish, representing different body sizes, marine habitats, and feeding modes, and thus varying exposure scenarios. Our findings from GC-HRMS SIM chromatography demonstrate that several tire additives are taken up into tissues. Although the available data indicates many tire-derived organic chemicals do not seem to bioaccumulate, mapping of tire rubber particle and chemical distributions in Arctic coastal systems, dose-response toxicity testing and risk assessments of environmental concentrations are warranted, also with a view to potential trophic transfer within the Arctic marine food chain.


Method for retrieval of aerosol optical depth from multichannel irradiance measurements

Sztipanov, Milos; Li, Wei; Dahlback, Arne; Stamnes, Jakob J.; Svendby, Tove Marit; Stamnes, Knut

We present, to the best of our knowledge, a new method for retrieval of aerosol optical depth from multichannel irradiance measurements. A radiative transfer model is used to simulate measurements to create the new aerosol optical depth retrieval method. A description of the algorithm, simulations, proof of principle, merits, possible future developments and implementations is provided. As a demonstration, measurements in the New York City area are simulated based on the specific channel configuration of an existing multichannel irradiance instrument. Verification of the method with irradiance measurement data is also provided.

Optical Society of America


Arctic Tropospheric Ozone Trends

Law, Kathy S.; Hjorth, Jens Liengaard; Pernov, Jakob B.; Whaley, Cynthia; Skov, Henrik; Coen, Martine Collaud; Langner, Joakim; Arnold, Stephen R.; Tarasick, David; Christensen, Jesper; Deushi, Makoto; Effertz, Peter; Faluvegi, Greg; Gauss, Michael; Im, Ulas; Oshima, Naga; Petropavlovskikh, Irina; Plummer, David; Tsigaridis, Kostas; Tsyro, Svetlana; Solberg, Sverre; Turnock, Stephen

Observed trends in tropospheric ozone, an important air pollutant and short-lived climate forcer (SLCF), are estimated using available surface and ozonesonde profile data for 1993–2019, using a coherent methodology, and compared to modeled trends (1995–2015) from the Arctic Monitoring Assessment Program SLCF 2021 assessment. Increases in observed surface ozone at Arctic coastal sites, notably during winter, and concurrent decreasing trends in surface carbon monoxide, are generally captured by multi-model median trends. Wintertime increases are also estimated in the free troposphere at most Arctic sites, with decreases during spring months. Winter trends tend to be overestimated by the multi-model medians. Springtime surface ozone increases in northern coastal Alaska are not simulated while negative springtime trends in northern Scandinavia are not always reproduced. Possible reasons for observed changes and model performance are discussed including decreasing precursor emissions, changing ozone dry deposition, and variability in large-scale meteorology.

American Geophysical Union (AGU)


Biological Uptake of Organic Contaminants from Car Tire Particles

Halsband, Claudia; Hägg, Fanny; Galtung, Kristin; Herzke, Dorte; Booth, Andrew Michael; Nikiforov, Vladimir


Moisture transport into the Arctic in a past and future climate

Eckhardt, Sabine; Svendby, Tove Marit; Steensen, Birthe Marie Rødssæteren; Myhre, Gunnar; Gjermundsen, Ada; Oliviè, Dirk Jan Leo


Skogens helsetilstand i Norge. Resultater fra skogskadeovervåkingen i 2022

Timmermann, Volkmar; Børja, Isabella; Clarke, Nicholas; Gohli, Jostein; Hietala, Ari Mikko; Jepsen, Jane Uhd; Krokene, Paal; Lislegård, Harald Haga; Nagy, Nina Elisabeth; Nyeggen, Hans; Solberg, Sverre; Solheim, Halvor; Solvin, Thomas Mørtvedt; Svensson, Arvid; Tollefsrud, Mari Mette; Vindstad, Ole Petter Laksforsmo; Økland, Bjørn; Aas, Wenche

Skogens helsetilstand påvirkes i stor grad av klima og værforhold, enten direkte ved tørke, frost og vind, eller indirekte ved at klimaet påvirker omfanget av soppsykdommer og insektangrep. Klimaendringene og den forventede økningen i klimarelaterte skogskader gir store utfordringer for forvaltningen av framtidas skogressurser. Det samme gjør invaderende skadegjørere, både allerede etablerte arter og nye som kan komme til Norge i nær framtid. I denne rapporten presenteres resultater fra skogskadeovervåkingen i Norge i 2022 og trender over tid for følgende temaer:
(i) Landsrepresentativ skogovervåking;
(ii) Intensiv skogovervåking;
(iii) Overvåking av bjørkemålere i Troms og Finnmark;
(iv) Barkbilleovervåkingen;
(v) Furuvednematode;
(vi) Askeskuddsyke;
(vii) Andre spesielle skogskader i 2022.



Local organic pollutants in the Arctic: Sentinels for polar environmental change

Kallenborn, Roland; Ali, Aasim Musa Mohamed; Drotikova, Tatiana; Hartz, William Frederik


The atmospheric fate of 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH): spatial patterns, seasonal variability, and deposition to Canadian coastal regions

Oh, Jenny; Shunthirasingham, Chubashini; Lei, Ying Duan; Zhan, Faqiang; Li, Yuening; Dalpé Castilloux, Abigaëlle; Ben Chaaben, Amina; Lu, Zhe; Lee, Kelsey; Gobas, Frank A. P. C.; Eckhardt, Sabine; Alexandrou, Nick; Hung, Hayley; Wania, Frank

Brominated flame retardants (BFRs) that are gradually being phased out are being replaced by emerging BFRs. Here, we report the concentration of the α- and β-isomers of 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH; also known as DBE-DBCH) in over 300 air, water, and precipitation samples collected between 2019 and 2022 using active air and deposition sampling as well as networks of passive air and water samplers. The sampling region includes Canada's most populated cities and areas along the St. Lawrence River and Estuary, Quebec, as well as around the Salish Sea, British Columbia. TBECH was detected in over 60 % of air samples at levels comparable to those of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47). Concentrations of TBECH and BDE-47 were typically higher in urban areas, with stronger correlations with population density during warmer deployments. Uniform α-  β-TBECH ratios across space, time, and environmental media indicate the highly similar atmospheric fate of the two isomers. Although TBECH air concentrations were strongly related to temperature in urban Toronto and a remote site on the east coast, the lack of such dependence at a remote site on the west coast can be explained by the small seasonal temperature range and summertime air mass transport from the Pacific Ocean. Despite there being no evidence that TBECH has been produced, or imported for use, in Canada, it is now one of the most abundant gaseous BFRs in the Canadian atmosphere. The recorded spatial and temporal variability of TBECH suggest that its emissions are not constrained to specific locations but are generally tied to the presence of humans. The most likely explanation for its environmental occurrence in Canada is the release from imported consumer products containing TBECH. Chiral analysis suggests that despite its urban origin, at least some fraction of TBECH has experienced enantioselective processing, i.e., has volatilized from reservoirs where it has undergone microbial transformations. Microbial processes in urban soils and in marine waters may have divergent enantioselectivity.


Image-Text Connection: Exploring the Expansion of the Diversity Within Joint Feature Space Similarity Score

Mohammadi, Mahsa; Eftekhari, Mahdi; Hassani, Amirhossein

Cross-modal representation learning aims to learn a shared representation space where data from multiple modalities can be effectively compared, fused, and understood. This paper investigates the role of increased diversity in the similarity score matrix in enhancing the performance of the CLIP (Contrastive Language-Image Pretraining), a multi-modal learning model that establishes a connection between images and text within a joint embedding space. Two transforming approaches, sine and sigmoid (including two versions), are incorporated into the CLIP model to amplify larger values and diminish smaller values within the similarity matrix (logits). Hardware limitations are addressed using a more compact text encoder (DistilBERT) and a pre-trained ResNet50 image encoder. The proposed adaptations are evaluated on various benchmarks, including image classification and image/text retrieval tasks, using 10 benchmark datasets such as Food101, Flickr30k, and COCO. The performance of the adapted models is compared to the base CLIP model using Accuracy, mean per class, and Recall@k metrics. The results demonstrate improvements in Accuracy (up to 5.32% enhancement for the PatchCamelyon dataset), mean per class (up to 14.48% enhancement for the FGVCAircraft dataset), and retrieval precision (with an increase of up to 45.20% in Recall@1 for the COCO dataset), compared to the baseline algorithm (CLIP).

IEEE (Institute of Electrical and Electronics Engineers)


Monitoring of environmental contaminants in air and precipitation. Annual report 2022.

Halvorsen, Helene Lunder; Pfaffhuber, Katrine Aspmo; Nipen, Maja; Bohlin-Nizzetto, Pernilla; Berglen, Tore Flatlandsmo; Nikiforov, Vladimir; Hartz, William Frederik

This report presents air monitoring data from 2022 for the Norwegian monitoring programme "Atmospheric contaminants". The results cover 260 organic compounds (regulated and non-regulated) and 16 compound groups, 14 heavy metals, and a selection of organic chemicals of concern.



Monitoring of environmental contaminants in freshwater food webs (MILFERSK) 2022

Jartun, Morten; Økelsrud, Asle; Bæk, Kine; Rundberget, Thomas; Øxnevad, Sigurd; Ruus, Anders; Grung, Merete; Enge, Ellen Katrin; Hanssen, Linda; Harju, Mikael; Johansen, Ingar

Norsk institutt for vannforskning


Environmental Contaminants in an Urban Fjord, 2022

Ruus, Anders; Grung, Merete; Jartun, Morten; Bæk, Kine; Rundberget, Thomas; Beylich, Bjørnar; Hanssen, Linda; Borgå, Katrine; Helberg, Morten

Norsk institutt for vannforskning


Monitoring of POPs and CECs in air at the Zeppelin observatory, Ny-Ålesund

Halvorsen, Helene Lunder; Nipen, Maja; Bohlin-Nizzetto, Pernilla; Nikiforov, Vladimir; Hartz, William Frederik