Publications

Impact of Medium-Energy Electron Precipitation on the Middle Atmosphere and on Climate in Decadal Simulations

Orsolini, Yvan J.; Guttu, Sigmund; Stordal, Frode

Observation of the EPP indirect effect by Odin/SMR following the two latest northern SSW events

Pérot, Kristell; Orsolini, Yvan J.

The Atlantic Multidecadal Variability phase-dependence of teleconnection between the North Atlantic Oscillation in February and the Tibetan Plateau in March

Li, Jingyi; Li, Fei; He, Shengping; Wang, Huijun; Orsolini, Yvan J.

American Meteorological Society

Error Prediction of Air Quality at Monitoring Stations Using Random Forest in a Total Error Framework

Lepioufle, Jean-Marie; Marsteen, Leif; Johnsrud, Mona

Instead of a flag valid/non-valid usually proposed in the quality control (QC) processes of air quality (AQ), we proposed a method that predicts the p-value of each observation as a value between 0 and 1. We based our error predictions on three approaches: the one proposed by the Working Group on Guidance for the Demonstration of Equivalence (European Commission (2010)), the one proposed by Wager (Journal of Machine Learning Research, 15, 1625–1651 (2014)) and the one proposed by Lu (Journal of Machine Learning Research, 22, 1–41 (2021)). Total Error framework enables to differentiate the different errors: input, output, structural modeling and remnant. We thus theoretically described a one-site AQ prediction based on a multi-site network using Random Forest for regression in a Total Error framework. We demonstrated the methodology with a dataset of hourly nitrogen dioxide measured by a network of monitoring stations located in Oslo, Norway and implemented the error predictions for the three approaches. The results indicate that a simple one-site AQ prediction based on a multi-site network using Random Forest for regression provides moderate metrics for fixed stations. According to the diagnostic based on predictive qq-plot and among the three approaches used in this study, the approach proposed by Lu provides better error predictions. Furthermore, ensuring a high precision of the error prediction requires efforts on getting accurate input, output and prediction model and limiting our lack of knowledge about the “true” AQ phenomena. We put effort in quantifying each type of error involved in the error prediction to assess the error prediction model and further improving it in terms of performance and precision.

MDPI

Real-time measurement of radionuclide concentrations and its impact on inverse modeling of 106Ru release in the fall of 2017

Tichý, Ondřej; Hýza, Miroslav; Evangeliou, Nikolaos; Šmídl, Václav

Concentrations and endocrine disruptive potential of phthalates in marine mammals from the Norwegian Arctic

Routti, Heli Anna Irmeli; Harju, Mikael; Lühmann, Katharina; Aars, Jon; Ask, Amalie; Goksøyr, Anders; Kovacs, Kit M.; Lydersen, Christian

Ftalater er organiske stoffer som hovedsakelig brukes til å gjøre plast mykere, særlig i PVC. Produksjonen av disse forbindelsene er ikke regulert på globalt nivå. Vi undersøkte nivåer av 12 ftalater i fett/spekk fra blåhval, finnhval, grønlandshval og isbjørn fra norsk Arktis. I tillegg målte vi nivåer av nedbrytningsprodukter av ftalater i plasma fra isbjørn. Bis(2-etylhexyl) ftalat (DEHP) var den eneste ftalat-forbindelsen som ble kvantifisert i prøvene. DEHP var til stede i de fleste hvalprøvene og nivåene i blå- og finnhvalspekk var lik nivåer av kjente miljøgifter som PCBer og organiske plantevernmidler. Nedbrytningsprodukter av ftalater ble funnet i lave konsentrasjoner i noen få isbjørnprøver. I tillegg undersøkte vi ftalaters potensial til å forstyrre finnhvalenes kjernereseptorer. Kjernereseptorer er proteiner som regulerer gener. De studerte reseptorene er viktige for å regulere blant annet metabolisme, stressresponser og energibalanse. Vi fant at DEHP både kan øke og hemme aktiviteten til skjoldbruskkjertelhormonreseptor, men da i høyere konsentrasjoner enn det som ble målt i spekk-/fettprøvene. Siden de studerte finnhvalreseptorene er helt eller nesten like de som finnes hos mange andre arter inkludert blåhval, vågehval, spekkhoggere, hvithval, isbjørn og mennesker, er resultatene også relevante for disse artene. Dette studiet bidrar til å øke kunnskapen om plastrelaterte stoffer og deres potensial til å forstyrre hormonsystemet hos marine pattedyr fra norsk Arktis.

Elsevier

Trick or treat? Ingestion of biofouled plastic fibres by sea urchins

Halsband, Claudia; Abrahams, Alexandra Kate; Bourgeon, Sophie; Herzke, Dorte

SEVIRI Aerosol Optical Depth Validation Using AERONET and Intercomparison with MODIS in Central and Eastern Europe

Ajtai, Nicolae; Mereuta, Alexandru; Stefanie, Horatiu; Radovici, Andrei; Botezan, Camelia; Zawadzka-Manko, Olga; Stachlewska, Iwona S.; Stebel, Kerstin; Zehner, Claus

MDPI

Low-cost sensors and networks. Overview of current status by the Norwegian Reference Laboratory for Air Quality.

Castell, Nuria

Denne rapporten går igjennom status innen mikrosensorteknologien. Den vurderer tilgjengelighet av produkter på markedet, målte parametere og datakvalitet, samt hvilke muligheter sensorene åpner for når de blir brukt riktig.

NILU

Ingested plastics in northern fulmars (Fulmarus glacialis): A pathway for polybrominated diphenyl ether (PBDE) exposure?

Neumann, Svenja; Harju, Mikael; Herzke, Dorte; Anker-Nilssen, Tycho; Christensen-Dalsgaard, Signe; Langset, Magdalene; Gabrielsen, Geir W.

Elsevier

Unexpected nascent atmospheric emissions of three ozone-depleting hydrochlorofluorocarbons

Vollmer, Martin K; Mühle, Jens; Henne, Stephan; Young, Dickon; Rigby, Matthew; Mitrevski, Blagoj; Park, Sunyoung; Lunder, Chris Rene; Rhee, Tae Siek; Harth, Christina M.; Hill, Matthias; Langenfelds, Ray L.; Guillevic, Myriam; Schlauri, Paul M.; Hermansen, Ove; Arduini, Jgor; Wang, Ray H. J.; Salameh, Peter K.; Maione, Michela; Krummel, Paul B.; Reimann, Stefan; O'Doherty, Simon; Simmonds, Peter G.; Fraser, Paul J.; Prinn, Ronald G.; Weiss, Ray F.; Steele, L. Paul

Life Cycle Assessment for renewable energy systems

Bouman, Evert Alwin

Målinger av PM10 i Lohavn. April og mai 2020.

Hak, Claudia; Tønnesen, Dag

On behalf of Hav Eiendom, NILU – Norwegian Institute for Air Research carried out measurements of particulate matter (PM10) in Lohavn in Oslo. The area will be developed into a new urban area with residential buildings, school, outdoor areas and businesses. The PM-concentration was measured at three locations in Lohavn to map the PM-distribution and possible sources. The measurement project took place in spring 2020. Possible effects of Covid-shutdown, variations in amount of traffic in the area and meteorological variations on the PM concentration are discussed.

The measurement results show a lower PM-concentration than in the measurement period 2016/17. The reason was probably the disappearance of temporary sources which led to periodically high concentrations in 2016/17. The highest PM10-concentrations were observed with winds from the south-southwest (which dominates during the day).

NILU