“NOAA provides imagery that basically says, ‘We think the pixels in this image are on fire right now,’” says Ryan Galleher, engineering program manager in Google’s Search and Crisis Response division. “They’re using their own fire detection algorithm that runs every five minutes, 24/7. We ingest that data, we run our own fire delineation algorithm against that to sort of draw a boundary around those hot pixels as the fire grows out.”

The result is a squiggly line that marks the wildfire’s perimeter in Google Maps. Galleher says the updates happen roughly every hour. That’s perhaps a little too slow to help people at ground zero of a devastatingly rapid firestorm like 2018’s Camp Fire, but it’s helpful for tracking slower blazes.

The product doesn’t really offer any kind of predictive information, so it won’t suggest where the fire may be spreading next if you’re trying to figure out your best evacuation route. Google says it has ambitions to add this guidance in the future, but right now it’s focused on detection and not forecasting. And when it comes to especially remote rural areas, there may still be information gaps there, particularly in areas so underdeveloped that the roads don’t really show up on maps in the first place. In those situations, reliable cell service might also be an issue, so Google’s only real proposal for now is to download offline maps in advance if you can.

Google first started building emergency response information into its services about a decade ago, when Googlers in Haifa, Israel, spotted a massive fire blazing in the distance and wondered about its exact location. The lack of easily parsable information online about this event, which was the Mount Carmel forest fire, led them to build what was the company’s first crisis alert product.

Several years later, Google started showing Android users “SOS” alerts, notifications that a natural or man-made hazard was happening nearby. Clicking on the notification takes users to a search results page with a giant red banner on top and information from local agencies collated below it. It’s this same SOS tech infrastructure that’s been used to send out Covid-19 alerts this year, Google says. And even more recently, the company started using Android phones as mini-seismometers to detect earthquakes. (Because, again, 2020.)

Google’s aggressive collection of data and search market dominance—and the way it is increasingly showing search results in the form of “Google cards” instead of directing users to other websites—has come under scrutiny in recent months. But when it comes to emergency services, the intended audience might just be a little too busy to pause and consider the implications.

More Great WIRED Stories