Found 9759 publications. Showing page 231 of 391:
2009
Modelled sources of airborne microplastics collected at a remote Southern Hemisphere site
Airborne microplastics have emerged in recent years as ubiquitous atmospheric pollutants. However, data from the Southern Hemisphere, and remote regions in particular, are sparse. Here, we report airborne microplastic deposition fluxes measured during a five-week sampling campaign at a remote site in the foothills of the Southern Alps of New Zealand. Samples were collected over 24-hour periods for the first week and for 7-day periods thereafter. On average, atmospheric microplastic (MP) deposition fluxes were six times larger during the 24-hour sampling periods (150 MP m−2 day−1) than during the 7-day sampling periods (26 MP m−2 day−1), highlighting the importance of sampling frequency and deposition collector design to limit particle resuspension. Previous studies, many of which used weekly sampling frequencies or longer, may have substantially underestimated atmospheric microplastic deposition fluxes, depending on the study design. To identify likely sources of deposited microplastics, we performed simulations with a global dispersion model coupled with an emissions inventory of airborne microplastics. Modelled deposition fluxes are in good agreement with observations, highlighting the potential for this method in tracing sources of deposited microplastics globally. Modelling indicates that sea-spray was the dominant source when microplastics underwent long-range atmospheric transport, with a small contribution from road dust.
Elsevier
2024
2014
2014
Modellering av vulkanaske i norsk luftfrom. Pkt. 1.3 Enkle forbedringer av utslippsestimat. NILU OR
The report describes how a transport model is used to simulate the emission of ash from volcanic eruptions and how the ash emissions can be described in the model. A number of methods for calculating ash emissions are presented and the development of improved ash emissions by manual analysis of satellite data is presented.
2013
2017
Modelling and mapping of degradation of built environment from available data and GIS based information tools. Umwelt-bundesamt. Texte 24/99
1999
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2009
This report was requested by the Norwegian Public Roads Administration (Statens vegvesen) to provide information concerning non-exhaust traffic emissions in Oslo and the impact of changes in environmental speed limits on these emissions. This report provides the results of calculations made with the dispersion model EPISODE coupled to the NORTRIP road dust emission model, a recently developed emission model for calculating non-exhaust emissions. The change in modelled emissions due to changes in environmental speed limit are calculated for two different speed scenarios, where 'speed limit' and 'realistic speed' changes are compared. In addition the impact of the environmental speed limit is compared to other road dust control measures involving studded tyre share and heavy duty vehicle reduction, taken from a previous report.
2013