Open source software to help cities plant in search of clean air


Software to help cities use street planting to reduce citizens’ exposure to air pollution has been developed by researchers at the University of Birmingham.

Street planting, or “green infrastructure”, is an essential part of the urban realm, but there is a misconception that plants remove or “absorb” a lot of pollution. Instead, planting on this scale serves primarily to redistribute pollution by altering air currents in streets and along open roads.

For this reason, not only the position and quantity of planting on a street, but also the layout and orientation of that street, are critical to its impacts on local air quality.

The software – the Green infrastructure for roadside air quality or ‘GI4RAQ’ platform – was designed by experts from the Forestry Research Institute (BIFOR) and the School of Geography, Earth Sciences and the Environment at the University of Birmingham, in partnership with practitioner organizations including: Transport for London, Greater London Authority and Birmingham City Council. It is the result of three years of collaboration, funded mainly by three Innovation grants from the Natural Environment Research Council.

Free to use and open source, the software allows practitioners to estimate the evolution of pollutant concentrations (over the entire cross section of a street) resulting from different planting patterns. It focuses on the main pollutants of road transport: NO2 (nitrogen dioxide) and PM2.5 (fine particles). Its calculations draw on wind data from monitoring stations across the UK and determine how bottom wind conditions interact with user-specified local urban form and planting.

The performance of the software and the underlying science are documented in an article published last month in the open access journal, Forests.

Principal Investigator Dr James Levine says: “By reducing our exposure to pollution from nearby vehicles, strategic planting can complement essential emission reductions to reduce health impacts. But that’s not as simple as thinking that any plantation will do good – if it’s blind, it’s just as likely to have a negative impact. There are many good reasons to invest in green infrastructure, but if we are planting in the name of improving air quality, we need to make sure it delivers real benefits. By estimating the benefits during planning, we can ensure that the right programs are robust to cost reduction and fully realized.

Informed by their work with Dr Levine, Transport for London is currently exploring a potential “healthy and resilient streets” program with the Greater London Authority. Dr Levine is also in discussions with The Mersey Forest and Liverpool City Council regarding a project in central Liverpool.

Paul Nolan OBE, Director of the Mersey Forest, commented: “The GI4RAQ platform bridges the gap between academic researchers and organizations like The Mersey Forest, cutting through the often mixed messages regarding the impacts of vegetation on quality. urban air, in support of projects offering real and lasting benefits.

The GI4RAQ team is led by Dr Levine and includes: PhD student Helen Pearce, who wrote the open source code on air quality; Professor Rob MacKenzie (Director of BIFOR) and Dr Xiaoming Cai; Tommy Morrison, Chris Thompson and Matt Sadler of Wild Ilk Design Studio, who developed the web interface; all with funding from the Natural Environment Research Council through grants, NE / S00940X / 1, NE / S013814 / 1, NE / S00582X / 1 and NE / S003487 / 1, and scholarship, NE / R011265 / 1.

Notes to editor:

  • For media inquiries, please contact Beck Lockwood, Press Office, University of Birmingham, tel. : +44 (0) 781 3343348: e-mail: [email protected]
  • The University of Birmingham is ranked among the top 100 institutions in the world. His work brings people from all over the world to Birmingham, including researchers, teachers and more than 6,500 international students from over 150 countries.
  • Clean Air is a central theme of the Institute for Global Innovation at the University of Birmingham, creating internationally leading interdisciplinary research, publications and impact, drawing on an established experience of academic, focused activities on policies and engagement.
  • Pearce, Levine et al (2021). “Roadside Air Quality Green Infrastructure Platform Presentation (GI4RAQ): Estimation of Site-Specific Changes in the Dispersion of Vehicle Pollution Near the Source.” Forests.


Leave A Reply