Next Article in Journal
Seasonal Variations and Chemical Predictors of Oxidative Potential (OP) of Particulate Matter (PM), for Seven Urban French Sites
Next Article in Special Issue
Bacteria as Cloud Condensation Nuclei (CCN) in the Atmosphere
Previous Article in Journal
Statistical Analysis of the Spatiotemporal Distribution of Ozone Induced by Cut-Off Lows in the Upper Troposphere and Lower Stratosphere over Northeast Asia
Previous Article in Special Issue
PM1 in Ambient and Indoor Air—Urban and Rural Areas in the Upper Silesian Region, Poland
Open AccessArticle

On the Impact of Trees on Ventilation in a Real Street in Pamplona, Spain

1
Atmospheric Pollution Division, Environmental Department, CIEMAT, 28040 Madrid, Spain
2
Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, University of Salento, 73100 Lecce, Italy
3
Department of Geography, National University of Singapore 119260, Singapore
*
Authors to whom correspondence should be addressed.
Atmosphere 2019, 10(11), 697; https://doi.org/10.3390/atmos10110697
Received: 4 October 2019 / Revised: 7 November 2019 / Accepted: 8 November 2019 / Published: 12 November 2019
(This article belongs to the Special Issue 10th Anniversary of Atmosphere: Air Quality)
This paper is devoted to the quantification of changes in ventilation of a real neighborhood located in Pamplona, Spain, due to the presence of street trees Pollutant dispersion in this urban zone was previously studied by means of computational fluid dynamic (CFD) simulations. In the present work, that research is extended to analyze the ventilation in the whole neighborhood and in a tree-free street. Several scenarios are investigated including new trees in the tree-free street, and different leaf area density (LAD) in the whole neighborhood. Changes between the scenarios are evaluated through changes in average concentration, wind speed, flow rates and total pollutant fluxes. Additionally, wind flow patterns and the vertical profiles of flow properties (e.g., wind velocity, turbulent kinetic energy) and concentration, horizontally-averaged over one particular street, are analyzed. The approach-flow direction is almost perpendicular to the street under study (prevailing wind direction is only deviated 4º from the perpendicular direction). For these conditions, as LAD increases, average concentration in the whole neighborhood increases due to the decrease of wind speed. On the other hand, the inclusion of trees in the street produces an increase of averaged pollutant concentration only within this street, in particular for the scenario with the highest LAD value. In fact, the new trees in the street analyzed with the highest LAD value notably change the ventilation producing an increase of total pollutant fluxes inward the street. Additionally, pollutant dispersion within the street is also influenced by the reduction of the wind velocity along the street axis and the decrease of turbulent kinetic energy within the vegetation canopy caused by the new trees. Therefore, the inclusion of new trees in a tree-free street should be done by considering ventilation changes and traffic emissions should be consequently controlled in order to keep pollutant concentration within healthy levels. View Full-Text
Keywords: CFD modeling; street ventilation; trees; urban air quality CFD modeling; street ventilation; trees; urban air quality
Show Figures

Figure 1

MDPI and ACS Style

Santiago, J.-L.; Buccolieri, R.; Rivas, E.; Sanchez, B.; Martilli, A.; Gatto, E.; Martín, F. On the Impact of Trees on Ventilation in a Real Street in Pamplona, Spain. Atmosphere 2019, 10, 697.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop