AirNow fire map contains data from PurpleAir sensors (that’s what the little circles represent), and Watch Duty, a nonprofit wildfire tracking app, also displays PurpleAir data. However, possibly due to different calculations and processing delays, the air quality index reported by the same sensors can vary significantly from map to map. For so-called PM2.5 pollution, or miniature inhalable particles of smoke and dust, the PurpleAir sensor located south of Los Angeles International Airport simultaneously reported an air quality index of 28 on the AirNow website, 20 on WatchDuty and 5 on the PurpleAir website on Monday . official website.
Each of these values generally indicates vigorous air, but things can get more complicated when other types of data are added to the calculations. That’s exactly what companies like BreezoMeter and Ambee are doing, hoping to provide what they call true “hyperlocal” estimates over many miles between certain sensor locations.
BreezoMeter was founded in Israel and raised tens of millions of dollars in venture capital before Google acquired it in 2022 for more than $200 million, according to data. Israeli media. (Google declined to comment on the value of the deal.) It uses air quality data evident in the Weather app on Apple devices and the Google Maps app. In turn, the Indian startup Ambee is responsible for air quality data in the WeatherBug application, which is one of the most popular weather applications in the world.
Yael Maguire, vice president of geographic sustainability at Google, tells BreezoMeter estimates air quality hourly for a wide range of pollutants and locations, generating more data than many government systems. For calculations, the company uses information collected not only from EPA and PurpleAir sensors, but also from satellites and other sources such as weather and traffic reports. According to the company’s CEO Jaideep Singh Bachher, similar data is incorporated into Ambee’s proprietary algorithm. “We want to make the right data available to people whenever and wherever they need it,” he says.
Volckens says he doesn’t trust these systems. The low-cost PurpleAir sensors they exploit in part are not well suited to the conditions in which they are often used in the U.S., including wildfires, he says. He acknowledges, however, that while raw numbers are usually not true, these sensors can be true about 90 percent of the time in determining the advisory level – that scale from green to burgundy that is often enough for people to make decisions about how protect your health.
Andrew White, a PurpleAir representative, says they are sensors turned out to be accurate and that he has no control over how other services perform calculations using his data. Google’s Maguire says the company “provides industry-leading, highly accurate air quality information,” including “even in areas with limited monitoring.”
Jennifer Richmond-Bryant, an associate professor of forestry and environmental resources at North Carolina State University who has studied PurpleAir sensors, says that for anyone concerned about air quality, the safest bet is to trust the highest number or color level among the various services. “I have more confidence in AirNow’s numbers because I understand them,” he says. But “it doesn’t hurt to be too conservative when it comes to protecting yourself.”