The weather app and weather widget in iOS 12 display a new weather category: air quality.
This is immediately noticeable because the air Berlin is directly indicated as “unhealthy”. The fact that the air in a big city is much worse than in the country is probably clear due to the high volume of traffic with combustion engines. However, the categorisation as unhealtyh is a bit surprising.
The AQI (Air Quality Index) consists of according to Wikipedia measured values of ozone, particulate matter, nitrogen dioxide, sulphur dioxide and carbon monoxide. The 16 stations that record the measured values for Berlin are known as Berliner Luftgüte-Messnetz (BLUME). Now you might ask yourself how to measure the air of a city of 900 square kilometers with 16 stations. As usual it will be like always: you measure what you measure and extrapolate. There will be areas where the air is fresh like spring and measuring points where one truck after the other drives through.
One thing the weather app now shows us, however, might be the most important characteristic: that the air is affected to a great extent by human use. As usual, the environment itself should be completely indifferent to this – it simply falls back on us.
