27 Potential Impact of a Low Emission Zone on Street-Level Air …
175
concentration peak found in observations (136.5 µg m
−3 ) is better reproduced by
street-scale (128.7 µg m
−3 ) than by mesoscale (72.4 µg m
−3 ). It is also remarkable
the improvement of CALIOPE-Urban during the central hours of the day.
With regard to NO 2 sensitivity to a 15% decrease in NO x emissions, we see
that NO 2 levels systematically decrease following the same dynamics as the streetscale model with full NO x emissions. Furthermore, on a simulation executed for the
entire period of April and May 2013 we find an average difference between the NO 2
concentration outputs of these two model configurations of 5 µg m
−3 producing
lower concentration values with the reduced emission configuration, a significant
reduction of NO 2 levels taking into account the limitation that CMAQ was executed
with full emissions and used for background concentrations in both model runs.
27.4 On Going Work
Next steps are directed to decrease the emission uncertainties by integrating in the
system new emission and traffic data that has been collected in Barcelona, permitting
the inclusion of more realistic emission factors, traffic composition and intensity.
Then, we will apply this new emission inventory to assess the potential impact on NO 2
concentration levels of the LEZ in Barcelona by simulating the effect of restricting
the entrance to the ring-road to the banned vehicles. We will integrate the emissions
in both the mesoscale and the local scale model runs.
Acknowledgements BSC researchers acknowledge the grants CGL2013-46736-R, CGL201675725-R and COMRDI15-1-0011-04 of the Spanish Government. Jaime Benavides PhD work
is funded with a grant from the FPI Programme by the Spanish Ministry of the Economy and
Competitiveness, call 2014, with reference EEBB-I-17-12296.
References
1. Agència de Salut Pública, Avaluació de la qualitat de l’aire a la ciutat de Barcelona. Technical
report, Agència de Salut Pública, Barcelona (2016)
2. F. Amato, A. Karanasiou, P. Cordoba, A. Alastuey, T. Moreno, F. Lucarelli, S. Nava, G. Calzolai,
X. Querol, Effects of road dust suppressants on PM levels in a mediterranean urban area. Environ.
Sci. Tech. 48(14), 8069–8077 (2014)
3. M. Azzi, G. Johnson, An introduction to the generic reaction set photochemical smog mechanism, in Proceedings of the 11th International Clean Air Conference, August 1992 (1992),
pp. 451–462
4. Barcelona City Council, Mesura de govern: Programa de mesures contra la contaminació atmosfèrica. Technical report (2016)
5. M. Guevara, F. Martínez, G. Arévalo, S. Gassó, J.M. Baldasano, An improved system for modelling Spanish emissions: HERMESv2.0. Atmos. Environ. 81, 209–221 (2013)
6. C. Holman, R. Harrison, X. Querol, Review of the efficacy of low emission zones to improve
urban air quality in European cities. Atmos. Environ. 111, 161–169 (2015)
175
concentration peak found in observations (136.5 µg m
−3 ) is better reproduced by
street-scale (128.7 µg m
−3 ) than by mesoscale (72.4 µg m
−3 ). It is also remarkable
the improvement of CALIOPE-Urban during the central hours of the day.
With regard to NO 2 sensitivity to a 15% decrease in NO x emissions, we see
that NO 2 levels systematically decrease following the same dynamics as the streetscale model with full NO x emissions. Furthermore, on a simulation executed for the
entire period of April and May 2013 we find an average difference between the NO 2
concentration outputs of these two model configurations of 5 µg m
−3 producing
lower concentration values with the reduced emission configuration, a significant
reduction of NO 2 levels taking into account the limitation that CMAQ was executed
with full emissions and used for background concentrations in both model runs.
27.4 On Going Work
Next steps are directed to decrease the emission uncertainties by integrating in the
system new emission and traffic data that has been collected in Barcelona, permitting
the inclusion of more realistic emission factors, traffic composition and intensity.
Then, we will apply this new emission inventory to assess the potential impact on NO 2
concentration levels of the LEZ in Barcelona by simulating the effect of restricting
the entrance to the ring-road to the banned vehicles. We will integrate the emissions
in both the mesoscale and the local scale model runs.
Acknowledgements BSC researchers acknowledge the grants CGL2013-46736-R, CGL201675725-R and COMRDI15-1-0011-04 of the Spanish Government. Jaime Benavides PhD work
is funded with a grant from the FPI Programme by the Spanish Ministry of the Economy and
Competitiveness, call 2014, with reference EEBB-I-17-12296.
References
1. Agència de Salut Pública, Avaluació de la qualitat de l’aire a la ciutat de Barcelona. Technical
report, Agència de Salut Pública, Barcelona (2016)
2. F. Amato, A. Karanasiou, P. Cordoba, A. Alastuey, T. Moreno, F. Lucarelli, S. Nava, G. Calzolai,
X. Querol, Effects of road dust suppressants on PM levels in a mediterranean urban area. Environ.
Sci. Tech. 48(14), 8069–8077 (2014)
3. M. Azzi, G. Johnson, An introduction to the generic reaction set photochemical smog mechanism, in Proceedings of the 11th International Clean Air Conference, August 1992 (1992),
pp. 451–462
4. Barcelona City Council, Mesura de govern: Programa de mesures contra la contaminació atmosfèrica. Technical report (2016)
5. M. Guevara, F. Martínez, G. Arévalo, S. Gassó, J.M. Baldasano, An improved system for modelling Spanish emissions: HERMESv2.0. Atmos. Environ. 81, 209–221 (2013)
6. C. Holman, R. Harrison, X. Querol, Review of the efficacy of low emission zones to improve
urban air quality in European cities. Atmos. Environ. 111, 161–169 (2015)