Using dispersion models at microscale to assess long-term air pollution in urban hot spots: A FAIRMODE joint intercomparison exercise for a case study in Antwerp.

In the framework of the Forum for Air Quality Modelling in Europe (FAIRMODE), a modelling intercomparison exercise for computing NO2 long-term average concentrations in urban districts with a very high spatial resolution was carried out. This exercise was undertaken for a district of Antwerp (Belgium). Air quality data includes data recorded in air quality monitoring stations and 73 passive samplers deployed during one-month period in 2016. The modelling domain was 800 × 800 m2. Nine modelling teams participated in this exercise providing results from fifteen different modelling applications based on different kinds of model approaches (CFD - Computational Fluid Dynamics-, Lagrangian, Gaussian, and Artificial Intelligence). Some approaches consisted of models running the complete one-month period on an hourly basis, but most others used a scenario approach, which relies on simulations of scenarios representative of wind conditions combined with post-processing to retrieve a one-month average of NO2 concentrations. The objective of this study is to evaluate what type of modelling system is better suited to get a good estimate of long-term averages in complex urban districts. This is very important for air quality assessment under the European ambient air quality directives. The time evolution of NO2 hourly concentrations during a day of relative high pollution was rather well estimated by all models. Relative to high resolution spatial distribution of one-month NO2 averaged concentrations, Gaussian models were not able to give detailed information, unless they include building data and street-canyon parameterizations. The models that account for complex urban geometries (i.e. CFD, Lagrangian, and AI models) appear to provide better estimates of the spatial distribution of one-month NO2 averages concentrations in the urban canopy. Approaches based on steady CFD-RANS (Reynolds Averaged Navier Stokes) model simulations of meteorological scenarios seem to provide good results with similar quality to those obtained with an unsteady one-month period CFD-RANS simulations.

Integrated assessment of traffic impact in an Alpine region.

This paper reports the results of an integrated assessment of traffic impact on a tourist-popular high altitude region which includes mountain passes and road tunnels. A modeling system for air quality assessment and management has been established and revised. The system has been used to evaluate the impact of traffic due to the re-opening of the Mont Blanc tunnel: the increase in NO(x) concentrations ranges from 50% at the bottom of the upper valley to 150% near to tunnel entrance.

[Acquired systemic amyloidosis associated with monoclonal gammopathy]. / L'amiloidosi sistemica acquisita con gammapatia monoclonale.

A case of acquired systemic amyloidosis with monoclonal gammopathy in a woman aged 67 years is reported. Clinical features included macroglossia, restrictive cardiomyopathy, cutaneous purpura and carpal-tunnel syndrome. A short review on amyloidosis appears in the case discussion.

Microscale modelling simulations for the site characterization of air quality stations in an urban environment.

The presence of natural or artificial barriers placed near the air quality measuring stations located in an urban environment poses some problems in the assessment of their siting and significance. The atmospheric flow distortion induced by these structures can create situations that affect the concentration levels of measured pollutants. A modelling study at microscale of the pollutant dispersion in an urban environment has been performed to quantify these possible effects on measurements. The target domain is located in a central section of the city of Turin (northern Italy) around via della Consolata, near the location of an existing station of the regional monitoring network. The study involved the use of the modelling system Micro-Swift-Spray, which takes into account the presence of complex topographical barriers, including street canyons and squares surrounded by buildings. Two entire days have been simulated, to characterise both a critical and a more standard condition, with reconstruction of average flow, turbulence and hourly ground-level pollutant concentrations. Contributions from both traffic and building-heating sources have been considered and a comparison with measured concentrations has been performed to verify the representativeness of the measuring station with respect to both average conditions and spatial variability inside the considered region, otherwise very difficult to asses through a single and isolated measuring point.