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2013
2011
Shipping emissions in the port of Oslo: inventory, mitigation strategies and future scenario. NILU F
2014
2017
SHIPMATE - Ship traffic particulate matter emissions. Final project report. NILU report
I SHIPMATE-prosjektet er det gjennomført målinger av en rekke forurensningskomponenter og aerosoler på Mt. Zeppelin observatoriet i løpet av 2014 og 2015. Målet for prosjektet var 1) å kartlegge hvor mye skipstrafikken bidrar til de observerte svevestøv-nivåene og 2) identifisere tidsrom i eksisterende tidsserier som i betydelig grad er påvirket av lokale utslipp fra skipstrafikken. Det siste er viktig for at tidsserien skal kunne benyttes for å studere regionale trender for ulike forurensningskomponenter i atmosfæren. Basert på en vurdering av gunstig vindretning mot målestasjonen med samtidige skipsanløp til Ny-Ålesund, er det identifisert alt åtte 3-dagers episoder hvor utslipp fra skipsfart påvirker datagrunnlaget. I disse episodene bidro utslipp fra skipstrafikken med ca. 50% av konsentrasjoner av følgende tungmetaller: Cu, Ni, Zn og Cd. Disse resultatene understøttes av en berikelsesfaktoranalyse av prøvene. Forekomst av episoder hvor skipstrafikk påvirker målingene ved målestasjonen på Mt. Zeppelin forekommer derimot sjeldent.
2016
Per- and polyfluoroalkyl substances (PFAS) have gained significant global attention due to their extensive industrial use and harmful effects on various organisms. Among these, perfluoroalkyl acids (PFAAs) are well-studied, but their diverse precursors remain challenging to monitor. The Total Oxidizable Precursor (TOP) assay offers a powerful approach to converting these precursors into detectable PFAAs. In this study, the TOP assay was applied to samples from the East Asian-Australian Flyway, a critical migratory route for millions of shorebirds. Samples included shellfish from China's coastal mudflats, key stopover sites for these birds, and blood and liver samples from shorebirds overwintering in Australia. The results showed a substantial increase in perfluorocarboxylic acids (PFCAs) across all sample types following the TOP assay, with the most significant increases in shorebird livers (Sum PFCAs increased by 18,156 %). Intriguingly, the assay also revealed unexpected increases in perfluorosulfonic acids (PFSAs), suggesting the presence of unidentified precursors. These findings highlight the need for further research into these unknown precursors, their sources, and their ecological impacts on shorebirds, other wildlife, and potential human exposure. This study also provides crucial insights into the TOP assay’s strengths and limitations in studying PFAS precursor dynamics in biological matrices.
Elsevier
2025
Sheath formation time for spherical Langmuir probes
The formation time of the surrounding sheath of Langmuir probes in an ionospheric plasma has been studied to better understand the constraints this puts on the sampling frequency of a probe. A fully kinetic three-dimensional particle-in-cell model is used to simulate the temporal effects in the electron saturation region as the sheath forms. The stability of the probe current and the stability of the ion and electron density in the vicinity of the probe have been used to evaluate when the sheath was formed. Simulated results were compared with theoretical models and are in good agreement with the theoretical results. This shows that theoretical models can be used as guidance to estimate the formation time and to determine the sampling rate for a swept bias Langmuir system. Our results also show that the formation time is less affected by the plasma temperature and bias voltage as we move into the thick sheath regime, and will instead be determined by the plasma density. The presented results also show that applying a step function to the probe could be used to characterise ions species composition, or to estimate the ion density.
Cambridge University Press
2023
SF6 as a greenhouse gas: An assessment of Norwegian global sources and the global warming potential. NILU OR
1993
2011
This paper presents the validation results of Aerosol Optical Depth (AOD) retrieved from the Spinning Enhanced Visible Infrared Radiometer (SEVIRI) data using the near-real-time algorithm further developed in the frame of the Satellite-based Monitoring Initiative for Regional Air quality (SAMIRA) project. The SEVIRI AOD was compared against multiple data sources: six stations of the Aerosol Robotic Network (AERONET) in Romania and Poland, three stations of the Aerosol Research Network in Poland (Poland–AOD) and Moderate Resolution Imaging Spectroradiometer (MODIS) data overlapping Romania, Czech Republic and Poland. The correlation values between a four-month dataset (June–September 2014) from SEVIRI and the closest temporally available data for both ground-based and satellite products were identified. The comparison of the SEVIRI AOD with the AERONET AOD observations generally shows a good correlation (r = 0.48–0.83). The mean bias is 0.10–0.14 and the root mean square error RMSE is between 0.11 and 0.15 for all six stations cases. For the comparison with Poland–AOD correlation values are 0.55 to 0.71. The mean bias is 0.04–0.13 and RMSE is between 0.10 and 0.14. As for the intercomparison to MODIS AOD, correlations values were generally lower (r = 0.33–0.39). Biases of −0.06 to 0.24 and RMSE of 0.04 to 0.28 were in good agreement with the ground–stations retrievals. The validation of SEVIRI AOD with AERONET results in the best correlations followed by the Poland–AOD network and MODIS retrievals. The average uncertainty estimates are evaluated resulting in most of the AOD values falling above the expected error range. A revised uncertainty estimate is proposed by including the observed bias form the AERONET validation efforts.
MDPI
2021
2009
SESS report 2018. The State of Environmental Science in Svalbard – an annual report.
Svalbard Integrated Arctic Earth Observing System (SIOS)
2019
Separation of volcanic ash and sulfur dioxide from the Eyjafjallajökull eruption, April-May 2010. NILU F
2010
1999
2014
2022
2024
2000
2011