Found 9887 publications. Showing page 121 of 396:
2013
Particle number (PNC) and black carbon (BC) in European urban air quality networks. ETC/ACM Technical Paper, 2012/6
2013
2010
2013
Part 3: Trends in aerosol optical properties - forcing How translate European emission reductions? NILU F
2014
2012
2004
Parameterization of convective transport in a Lagrangian particle dispersion model and its evaluation. J. Appl. Meteorol. Climatol.
2007
2017
A comprehensive European dataset on monthly atmospheric NH3, acid gases (HNO3, SO2, HCl), and aerosols (NH+4, NO−3, SO2−4, Cl−, Na+, Ca2+, Mg2+) is presented and analysed. Speciated measurements were made with a low-volume denuder and filter pack method (DEnuder for Long-Term Atmospheric sampling, DELTA®) as part of the EU NitroEurope (NEU) integrated project. Altogether, there were 64 sites in 20 countries (2006–2010), coordinated between seven European laboratories. Bulk wet-deposition measurements were carried out at 16 co-located sites (2008–2010). Inter-comparisons of chemical analysis and DELTA® measurements allowed an assessment of comparability between laboratories.
The form and concentrations of the different gas and aerosol components measured varied between individual sites and grouped sites according to country, European regions, and four main ecosystem types (crops, grassland, forests, and semi-natural). The smallest concentrations (with the exception of SO2−4 and Na+) were in northern Europe (Scandinavia), with broad elevations of all components across other regions. SO2 concentrations were highest in central and eastern Europe, with larger SO2 emissions, but particulate SO2−4 concentrations were more homogeneous between regions. Gas-phase NH3 was the most abundant single measured component at the majority of sites, with the largest variability in concentrations across the network. The largest concentrations of NH3, NH+4, and NO−3 were at cropland sites in intensively managed agricultural areas (e.g. Borgo Cioffi in Italy), and the smallest were at remote semi-natural and forest sites (e.g. Lompolojänkkä, Finland), highlighting the potential for NH3 to drive the formation of both NH+4 and NO−3 aerosol. In the aerosol phase, NH+4 was highly correlated with both NO−3 and SO2−4, with a near-1:1 relationship between the equivalent concentrations of NH+4 and sum (NO−3+ SO2−4),of which around 60 % was as NH4NO3.
Distinct seasonality was also observed in the data, influenced by changes in emissions, chemical interactions, and the influence of meteorology on partitioning between the main inorganic gases and aerosol species. Springtime maxima in NH3 were attributed to the main period of manure spreading, while the peak in summer and trough in winter were linked to the influence of temperature and rainfall on emissions, deposition, and gas–aerosol-phase equilibrium. Seasonality in SO2 was mainly driven by emissions (combustion), with concentrations peaking in winter, except in southern Europe, where the peak occurred in summer. Particulate SO2−4 showed large peaks in concentrations in summer in southern and eastern Europe, contrasting with much smaller peaks occurring in early spring in other regions. The peaks in particulate SO2−4 coincided with peaks in NH3 concentrations, attributed to the formation of the stable (NH4)2SO4. HNO3 concentrations were more complex, related to traffic and industrial emissions, photochemistry, and HNO3:NH4NO3 partitioning. While HNO3 concentrations were seen to peak in the summer in eastern and southern Europe (increased photochemistry), the absence of a spring peak in HNO3 in all regions may be explained by the depletion of HNO3 through reaction with surplus NH3 to form the semi-volatile aerosol NH4NO3. Cooler, wetter conditions in early spring favour the formation and persistence of NH4NO3 in the aerosol phase, consistent with the higher springtime concentrations of NH+4 and NO−3. The seasonal profile of NO−3 was mirrored by NH+4, illustrating the influence of gas–aerosol partitioning of NH4NO3 in the seasonality of these components.
Gas-phase NH3 and aerosol NH4NO3 were the dominant species in the total inorganic gas and aerosol species measured in the NEU network. With the current and projected trends in SO2, NOx, and NH3 emissions, concentrations of NH3 and NH4NO3 can be expected to continue to dominate...
2021
2006
2006
HERIe was used to model the effect of changes to indoor climate on the risk of humidity-induced mechanical damage (cracking and plastic deformation) to wooden panels painted with stiff gesso in two Norwegian medieval stone churches: Kinn (mean relative humidity (RH, %) = 79%) on the humid west coast, and Ringsaker (mean RH = 49%) in the drier eastern part of the country. The risk involved in moving cultural heritage objects (paint on wood) between the churches and a conservation studio with more “ideal”, stable conditions was also modeled. A hypothetical reduction in RH to ~65% and, proportionally, of the climate fluctuations in Kinn, and an increase in the RH in Ringsaker to a more stable value of ~63% via conservation heating, were found to improve (Kinn) and uphold (Ringsaker) the conformity to relevant standards and significantly reduce the risk of damage, except in the scenario of moving objects from Ringsaker to a conservation studio, when the risk would increase. The use of conservation heating could save ~50% of the heating cost. The estimated risk reductions may be less relevant for objects kept in situ, where cracks in the original paint and gesso have developed historically. They may be more relevant when moving original objects away from their proofed climate into a conservation studio for treatment.
MDPI
2023
PAH measurements in air and moss around selected industrial sites in Norway 2015. NILU report
On request from the Norwegian Environment Agency a pilot study of atmospheric deposition of PAH around industrial enterprises in Norway has been carried out. The participation was voluntary and 10 industries located at 10 different sites financed their own participation. The survey is based on analysis of samples of naturally growing moss collected around the enterprises during the summer of 2015. In addition, passive air samplers for collection of volatile PAH were placed around 6 of the participating enterprises. Generally, the PAH level determined in moss collected around industrial sites were considerably higher than the PAH level found in moss collected at background sites. The levels of PAHs found in the air samples was low and often at the same level as found at the closest background site, for all out of two sites, i.e. Sunndal and Kristiansand. There is no clear indication that the industry is the only source to the levels of PAHs in moss. Hence, results from this pilot study, illustrates that moss and air samples together provide a more comprehensive information regarding the spatial distribution of PAH around the industrial sites.
2017
PAH measurements at Lista. January 2020 – December 2020.
On behalf of Aluminiumindustriens Miljøsekretariat (AMS) and Alcoa Lista, NILU – Norwegian institute for air research has
conducted a sampling campaign in the surroundings of the Alcoa Lista aluminium smelter in order to update the knowledge on PAH-concentrations around the smelter today. Samples were taken in the period January – December 2020 and
analysed for particle bound PAHs. As a consequence of reduced emissions compared to earlier measurements, the ambient
concentrations of benzo(a)pyrene (BaP) were reduced. BaP had an annual average concentration below the target value at
both sampling sites. At Huseby, the lower assessment threshold was exceeded. PAH-levels in the area were similar to those observed in Norwegian cities.
NILU
2021
2019