New measurements of the air quality in Copenhagen show high levels of ultrafine particles

The results from the project ‘Copenhagen Air View’, that has been carried out in collaboration with Google and Utrecht University, have just now been published


For two years, a Google Street View car with advanced air quality measuring equipment has been driving around all the streets of Copenhagen. The Google car has measured the levels of nitrogen dioxide (NO2), ultrafine particles (UFP) and soot (Black Carbon), all of which are characterized by being formed during or just after combustion and therefore provide insight into the local emissions of air pollution. The project has now been completed, and the City of Copenhagen, Google, and Utrecht University can therefore today publish the final maps of air pollution in the city, which the citizens can also study closely.

According to several researchers, the air pollution - including ultrafine particles –is causing many Copenhageners to die prematurely every year. However, ultrafine particles are not included in official statistics, as the EU has not set formal limit values for them. With Copenhagen Air View, it is the first time that the ultrafine particles concentration is measured down to street level - and along with other measurements of air pollution point results evident that there is need to act to make the city healthier, thinks technical and environmental mayor Ninna Hedeager Olsen (EL):

“It’s the first time we get a fine-meshed network showing pollution right down to street-level and on all roads in all of Copenhagen. The differences become very clear and it gives us an important knowledge about where we should concentrate our efforts to plan the city in a better way in order to protect the Copenhageners against the dangerous particles”, she says

In general, the air quality has become much better in Copenhagen over the last couple of years, but this trend does not seem to count for the big approach roads. The highest concentrations on the maps are seen at the city's major access roads such as Ågade, Lyngbyvejen and Folehaven, where there is a lot of car traffic. Air pollution on a busy street with lots of traffic is about three times as high compared to a quiet street with little traffic. In addition, there are significant ultrafine particle emissions from the airport. Vesterbro and the City Centre have higher measured levels of air pollution than other parts of the city that on the face of it can not be described by traffic alone. The lowest measurements have been conducted on residential streets on Frederiksberg.

According to Ninna Hedeager Olsen, the municipality must first and foremost use the conclusions to put pressure on national politicians, so that the municipality can do something real about the polluting cars in the city:

“Christiansborg must give us the tools we need to ensure the health of Copenhageners. Give us the opportunity to regulate traffic, not only on the basis of C0 2 emissions, but also on the basis of criteria on which car types emit the most harmful particles”, she says, referring to the possibility of introducing a detailed system for road pricing and expanding the environmental zones, which today only include lorries and vans, to also apply to private cars.

Until that happens, she will work to limit motoring and thus emissions through, for example, speed reductions and fewer parking spaces - and then the Copenhagen politicians must try to plan the city wiser, for example by offering the soft road users more green bike and walking routes away from car traffic or by locating new day care centers away from polluting roads.

Copenhagen Air View has been created by Google, the City of Copenhagen, and researchers from Utrecht University, in collaboration with Aarhus University (DCE - National Center for Environment and Energy). Google's Danish director, Malou Aamund, is pleased to be able to contribute to increasing understanding of the challenges associated with air pollution:

“Air pollution in Copenhagen is a problem that needs to be addressed. But action presupposes knowledge. That's why we at Google are really happy to have helped create completely new insights into the Copenhagen air and make them available to researchers, politicians - and the citizens themselves. It also shows how advanced technology can help solve some of the biggest challenges of the time when public authorities and private actors work well together”, says Malou Aamund.

The results of Google's measurements are plotted on three maps for respectively nitrogen dioxide (NO2), ultrafine particles (UFP) and soot (Black Carbon)

  • Click here for interactive maps
  • Click here for the maps in file format

Facts about the project:

  • Copenhagen Air View has been created by Google, the City of Copenhagen, and researchers from Utrecht University, in collaboration with Aarhus University (DCE - National Center for Environment and Energy).
  • Copenhagen Air View, as the project is called, was the first of its kind in Europe, since then London and Amsterdam have also joined.
  • The car's measuring equipment has been able to make measurements for every second and has made about 6 million measurements per measurement device.
  • Measurements made with the Street View car are sampled in the middle of the roadway and are therefore different from previously developed maps and measurements, mostly measured at the side of the road or at facades of buildings.
  • Utrecht University has been the scientific lead on the project and has been responsible for measuring equipment and data collection. The criteria for driving the Google Street View car have been determined together with Aarhus University (DCE) and the University of Copenhagen. The final data processing, validation of results and design of maps has been carried out by Utrecht University in close collaboration with Aarhus University DCE.
  • The Department of Public Health at the University of Copenhagen has also contributed to qualifying the data collection in relation to the use of the collected data in health research.
  • In general, air quality has improved in Copenhagen in recent years, but this trend does not seem to apply to motorways and major access roads, according to Google Street View car's measurements of NO2 . It is also on the approaches that the concentration of ultrafine particles and soot is worst.