How Researchers in LA Are Tackling Air Pollution in Neighborhoods with PurpleAir

How can you help contribute to air quality science every day? 

Well, thanks to one group of researchers in Los Angeles (LA), it’s easier than you might think.

In recent years, high-quality and precise air quality monitors have become far more affordable than they were in the past. And this has paved the way for community scientists to contribute to academic study of air quality, as well as know their air quality in their own home. 

In today’s blog, we’re diving deep into the history of air quality in LA. Then, we’ll highlight how researchers are using PurpleAir’s air quality monitors to study air pollution today. 

The History of Air Quality in Los Angeles 

Throughout the city’s history, Los Angeles has had a lot of difficulty with air pollution. Back in 1903, the haze from industrial smoke was so thick many residents mistook it for an eclipse. Shortly after that incident, city officials implemented various measures to reduce factory emissions. 

You can see how dense it was in this photo from the library collection from the University of California Los Angeles (UCLA) :  

Image from UCLA Library 


Despite these efforts, the air quality suffered again a few decades later in the 1940s-50s as vehicle use increased—also causing higher levels of particulate matter. With so much harmful air, many residents would carry small cloths or wear masks to avoid inhaling excessive pollution.  

The air quality in LA was so bad that it even affected the local airport as pilots struggled to see the runway when landing. Due to the geography of the region, temperature inversions were also common as they trapped the toxic air over the city.

All of these factors made LA’s air quality notoriously bad. 

Fast forward to today, and now the city has various organizations run by air pollution officials who implement stricter regulations to reduce air pollution in Los Angeles.  

Over the years, the city has improved air quality through all kinds of strategies like: 

Now, air pollution in Los Angeles is a lot better than it was in the past, but we can always strive to improve our air quality. And so, a group of researchers is working on developing a network of air quality monitors to do just that. 

How Researchers Are Using PurpleAir in LA 

In 2020, academic researchers in Los Angeles had a simple question. How could the city of LA better monitor particulate matter (PM2.5) in local neighborhoods hourly?

The challenge preventing this historically was that government air quality monitors were too sparse. In addition, residential air quality monitors were too costly or inaccurate. 

However, with the increased use and affordability of air quality monitors like PurpleAir, they believed that this would pose an opportunity for better data in combination with local monitoring systems used by other agencies. 

And so, the researchers started measuring air quality in one local neighborhood that incorporated both PurpleAir data and network data from LA county. They created a machine learning model which then allowed them to accurately predict particulate matter throughout the week. By combining both types of data, their readings of PM2.5 were far more precise than they were before. 

To conclude their findings, researchers determined that the increased use of PurpleAir monitors was a huge step towards empowering community scientists. We’re thrilled to see more research that helps everyone better understand the dangers of air pollution in our cities and neighborhoods.  

By making air quality data accessible for everyone, we can all make more informed decisions on our local air quality policies. We hope more cities take after Los Angeles by investing in air quality technology or by using the PurpleAir Map to see their city’s air quality in real time. 

Connect With PurpleAir 

At PurpleAir, there are tons of organizations and researchers around the world using our data—from Google to the EPA. We’re thrilled to see research like this being used to help local neighborhoods, and we look forward to seeing plenty more in the future. 

Are you a technology company or institution looking to work with PurpleAir? 

We’d love to connect and see how we can help you. Whether you’re interested in our air quality monitors or using our air quality data for your projects, feel free to reach out.