A team of UBC researchers has developed a way to measure greenhouse gas emissions at street level in cities.

UBC professor Andreas Christen and UBC geography graduate Joseph Lee created small sensors that attach to vehicles and measure carbon dioxide levels as they move around the city.

"We see major arterial roads, we see neighbourhoods where there are more emissions, such as downtown Vancouver," said Christen, an associate professor at UBC.

"We also see areas where there's some uptake of CO2 happening — for example, in large parks."

Christen said this allows them to collect data about how much carbon dioxide we emit and where emissions are the highest. They plan to use their data to make a map of where emissions are the highest in Vancouver.

The sensor attaches near the roof of the car, but is light enough to mount on a wider variety of vehicles like bikes and busses. (Joseph Lee/UBC)

Sensors tested on car share vehicles

To test the sensors, Christen and Lee drove Car2Go vehicles outfitted with the sensors around Vancouver for over three hours.

They found the highest emissions were in downtown Vancouver and on some arterial roads.

However to get a more accurate measurement of greenhouse gas emissions, Christen said they would need to roll them out on a much larger scale,

"We found you would need about 200 of these mobile sensors to map a city like Vancouver," he said. "A good way to do it would be to mount them continuously on things like taxis, buses, car-shares, even rental bikes."

The UBC team compared the data they gathered, to data collected from a tower above the City of Vancouver. (Joseph Lee/UBC)

Use in urban planning

Christen said being able to know how much and where greenhouse gas emissions are emitted in the city is important for urban planning strategies.

He said governments typically model emissions-based testing on large scales, but rarely at the levels of individual streets, blocks and neighbourhoods.

"Currently, we really only know how much CO2 we emit based on how much fuel we consume," said Christen.

"Urban planners would have a lot of use for this information … if we keep mapping and sampling over time, we can see how emissions change so we can measure if emissions-reducing strategies have been effective over time."

With files from Matt Meuse