With billions of data points streamed daily from satellites and monitoring stations, a stunning, interactive map shows just how bad pollution has become in real time. Its heat display of dangerous red blobs bleeding from global capitals and industrial areas show how air pollution is a major concern for populations of cities.
The map was launched by french startup AirVisual to coincide with the end of the COP22 climate discussions in Marrakech. Its creators wanted to demonstrate our collective failure to meet our health standards while also equipping citizens with the tools to keep track of air pollution themselves. AirVisual also produces three-day pollution forecasts for more than 5,000 cities – weather reports fit for the Anthropocene.
The state of the air is plotted against the Air Quality Index (AQI), an American standard of documenting a cocktail of harmful particles – carbon monoxide, sulfur dioxide, ground-level ozone, nitrogen dioxide and particle pollution. Especially dangerous is a form of particle pollution called PM2.5. This type of particulate matter is small (less than 2.5 micrometers) and can penetrate deep into human lungs and bloodstreams, causing health issues such as heart disease and asthma. According to the World Health Organization’s latest estimates, such related health problems cause the deaths of seven million people every year.
PM2.5 is thought by the WHO to be the best indicator of the level of health risks, and it considers a concentration greater than ten micrograms per cubic metre to qualify as a hazard. So, while the red clouds above cities are the most alarming, beware the greens too. For example, while it is unsurprising to see warm colours over India and eastern China, it is perhaps more worrying to see how far these plumes extend out to sea. Meanwhile, the accompanying wind speeds and directional arrows give an idea of how these pollutants are spreading from their emitters, most often from factories, car exhausts and from burning wood.