Origin of fine particles in sharper focus with free website

23 Oct 2018

Fine particles are bad for your health, causing respiratory and cardiovascular diseases plus premature death. Reliable data on their origin is desperately needed. TNO’s web application TOPAS provides policymakers and other stakeholders in over 200 European cities with free, up-to-date insight into the origin and sources of fine particles. The data provided are no more than 24 hours old with the option to look back to up to six weeks.

Where do fine particles come from?

Visit web application TOPAS and get direct insight into your local sources.


Insight into the origin of fine particles is necessary for effective policy

Fine particles are produced by fuel combustion, wear and tear and the processing of materials. Natural sources such as sea salt and Saharan sand also contribute to the amount of fine particles in the air. "For effective air quality policy, it is important to know the sources of fine particles in an area so that measures can be developed on the basis of this. Until recently, the so-called source allocation of fine particles was, to a certain extent, guesswork for policymakers. With our TOPAS tool, this can now be done more reliably and simply," says Martijn Schaap, a TNO researcher who has co-developed the web application with his team.

Built on TNO model and European knowledge

TOPAS was built on the basis of TNO knowledge, such as the atmospheric transport model LOTOS-EUROS. This model is supplied for TOPAS with information from weather models of the European Copernicus Atmospheric Monitoring System (CAMS). Schaap: "TOPAS provides the user with a thorough picture of the development of fine particles over the preceding six weeks. This way you can see for your own city the countries from which the particulate matter concentration originate. In addition, we make evident which sector contributes to the fine particles and to what extent. Users see the relationship between, among other things, industrial origin, large-scale energy generation, traffic and natural sources. The data are updated every 24 hours, and are offered free of charge."


The current free version is limited to six weeks of data. For policymakers who need more data, it is possible to receive additional data. TNO will continue to develop the current beta version in the coming months so that the level of detail of the data displayed is expanded. Martijn Schaap: "At the moment, the application only shows geographical origin at country level. We want to refine this to a provincial level, for example. We would also like to make rapid use of the data generated by Tropomi (TROPOspheric Monitoring Instrument) from Earth orbit. It will then be possible to identify emission sources even more precisely and quantify their impact."

This TNO project supports the following Sustainable Development Goals


Climate, Air and Sustainability

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