Interactive Map Lets You See the Air Quality of 1,000 Places Around the Globe

Quick, name a city around the globe with terrible air pollution problems. If smog-plagued Los Angeles or Beijing comes to mind, you’d be on the right track—the air quality in both cities is notoriously poor. It’s been so smoggy in Beijing over the past few years that a fake sun was set up because no one could see the real one, and gas masks have become a fashion statement.

So it’s no wonder that a Beijing-based environmental nonprofit, Air Quality Index China, is behind an interactive map that reveals real-time air pollution levels for 1,000 places worldwide.

There are smartphone apps that measure air quality but this map compiles data from official government agencies on the amount of ground-level ozone, particle pollution, carbon monoxide, sulfur dioxide, and nitrogen dioxide. All data for those five pollutants is assessed using the U.S. Environmental Protection Agency’s air quality index scale, and new readings are uploaded to the map every 15 minutes.

A bird’s-eye view of the map shows icons with different colors on them, using the EPA’s traditional color coding. A green symbol means the air quality is “good”; yellow indicates the air is “moderate”—it’s acceptable to everyone but people who are unusually sensitive to pollutants.

(Map: Courtesy waqi.info)

However, places that are orange are “unhealthy for sensitive groups”—think folks with asthma. Red locations are considered “unhealthy,” purple is “very unhealthy,” and maroon indicates air that is “hazardous” to people’s health.

On Tuesday afternoon, most of the United States had healthy air but the worst air pollution in the nation was—surprise, surprise—in the Los Angeles area. Reseda, a suburb in the San Fernando Valley with a bad reputation for smog, had an AQI ranking of 89, which is considered moderate but is just 11 points shy of the benchmark for unhealthy.

That’s not great but it’s certainly better than the air in Shahre Rey, a community on south side of Tehran, Iran. It had an AQI ranking of 238 on Tuesday afternoon—firmly in the “very unhealthy zone.” And then there’s Palangkaraya, Indonesia, which had a ranking of 999, according to the index. Haze from forest fires in the Southeast Asian country had blanketed the city.

About 7 million people die every year from the ill effects of airborne particulate matter, according to the World Health Organization. And although this map shows air pollution for most of the world, a savvy user will notice that there's little information for large swaths of the Global South. Given the rapid industrialization and development across Africa, getting that data—and then doing something about it—certainly seems like it should be a priority.