ELi5: What does air quality mean on the weather app and how do they calculate it?



ELi5: What does air quality mean on the weather app and how do they calculate it?

In: Earth Science

It’s a measure of foreign particulates in the air that can effect your respiratory system. It can be measured by air samples as well as being predicted by using meoterolgical analysis by looking how formations of polluted air are moving.

It’s a measure of pollutants in the air, different countries use different types of scales and generate an easy to interpret number or band/grade for you.

Most common are PM2.5 and PM10, PM stands for Particulate Matter, measured in micrometers.

They may also measure other sources of pollution such as carbon dioxide, carbon monoxide, nitrogen dioxide and sulphur dioxide.

To add, for most of the US, at least, most people don’t have to think about air quality. Where does it matter most? The west coast. We have forest fires out here, and if you’re down wind, air quality can be bad enough that you’re advised to not travel, keep your house sealed shut, try not to breathe the outside air. We get days or weeks where the sun is blocked by smoke, the sky turns red, and it smells like a fireplace everywhere all the time. It could be as bad as smoking a couple packs of cigarettes just by breathing. We own air filters that will screen 2.5 micron particles, but many of those odorless, tasteless gasses can be of sufficient concentration you feel light headed, dizzy, vision becomes unsteady… Just this summer the smoke from California alone washed over the whole country, to where parts of the east coast had air quality bad enough outdoor activity was considered unhealthy.