Why is the air sometimes worse in the country side?
Sometimes I get questions like: “The aircheckr widget is telling me now that the air is better away from the big road than on the big road itself. How is that possible?” I have to agree, this sounds counter-intuitive, but still it is possible in specific circumstances. Here is why:
Sometimes the Air Quality Index is better away from a big road than on the road itself. This sounds counter-intuitive, but still this is possible.
First of all, it is important to know that aircheckr is considering different pollutants. The aircheckr Air Quality Index (AQI) is an indication of the air quality based on the individual values of these pollutants. In fact, the AQI is mainly defined by the pollutant(s) with the worst concentrations at that moment. As the different pollutants have different (local) sources and are formed in a different way, this means that for two locations at a specific time a different (main) pollutant can be responsible for the AQI value.
Aspecific case where such counter-intuitive outputs are often occurring is when the pollutant ozone comes into play. Ground level ozone is a secondary pollutant. While other pollutants like NO2 or PM are directly emitted by specific sources like traffic, ozone is not. It is formed by chemical reaction of volatile organic compounds (VOCs) and NOx in the presence of sunlight. As a result, the highest levels of ozone pollution occur during periods of sunny weather.
Ozone cannot only be ‘produced’ in specific circumstances, but can also be degraded easily again. The latter happens more often in urbanized areas and close to the proximity of roads (traffic) due to the higher presence of NO in these areas. This means that ozone concentrations are often higher in the countryside. When concentration of ozone are very high and ozone is the main pollutant affecting our health due to its high concentrations, you can have the strange effect of a worse AQI in the countryside or further away from big roads then in the city center or on these roads.
Ozone can be degraded easily again and this happens more often in urbanized areas and close to the proximity of roads.
Of course, also other pollutants (like NO2 or PM) influence our health. Close to a big road the chances are high that the NO2 pollution will be worse than further away. But as “peaks” of high concentrations are very important for the short term effects on our health, the overall very high concentration of ozone is overruling the locally higher (but compared to ozone lower) concentration of the other pollutants.
You can read more about the ‘ozone paradox’ in this article of IRCELINE.
Air pollution causes 467.000 deaths in Europe each year. Once a silent and underestimated killer, it is now recognized as the single biggest environmental health risk. But there is hope. Scientific research has shown that reducing your exposure to air pollution is effectively helping. But how to do that? aircheckr provides detailed outside air quality information and tools needed to effectively reduce your exposure. It empowers people to actively or passively make better decisions and take actions in order to breathe better air. People are no longer defenseless. Improving the air at home/office or car, or reducing your exposure during biking or exercising is now possible. Together with its partners, aircheckr is working hard to integrate air quality information into a wide range of services, applications or devices.
You want to try aircheckr yourself? Check www.aircheckr.com or even better sign up here.
