You’ve probably heard about the plague of plastic trash in the oceans. You’ve seen YouTube videos of sea turtles with drinking straws in their noses, or whales with stomachs full of marine litter. But how much plastic is out there? Where is it coming from? We don’t really know, because we haven’t measured it. “There’s a paucity of data,” says Marcus Eriksen, cofounder of the 5 Gyres Institute, a nonprofit focused on ending plastic pollution.

Marine litter isn’t the only hazard whose contours we can’t fully see. The United Nations has 93 indicators to measure the environmental dimensions of “sustainable development,” and amazingly, the UN found that we have little to no data on 68 percent of them—like how rapidly land is being degraded, the rate of ocean acidification, or the trade in poached wildlife. Sometimes this is because we haven’t collected it; in other cases some data exists but hasn’t been shared globally, or it’s in a myriad of incompatible formats. No matter what, we’re flying blind. “And you can’t manage something if you can’t measure it,” says David Jensen, the UN’s head of environmental peacebuilding.

In other words, if we’re going to help the planet heal and adapt, we need a data revolution. We need to build a “digital eco­system for the environment,” as Jensen puts it.

The good news is that we’ve got the tools. If there’s one thing tech excels at (for good and ill), it’s surveillance, right? We live in a world filled with cameras and pocket computers, titanic cloud computing, and the eerily sharp insights of machine learning. And this stuff can be used for something truly worthwhile: studying the planet.

“If a vessel is spending its time in an area that has little tuna and a lot of sharks, that’s questionable.”

There are already some remarkable cases of tech helping to break through the fog. Consider Global Fishing Watch, a nonprofit that tracks the world’s fishing vessels, looking for overfishing. They use everything from GPS-like signals emitted by ships to satellite infrared imaging of ship lighting, plugged into neural networks. (It’s massive, cloud-scale data: over 60 million data points per day, making the AI more than 90 percent accurate at classifying what type of fishing activity a boat is engaged in.)

“If a vessel is spending its time in an area that has little tuna and a lot of sharks, that’s questionable,” says Brian Sullivan, cofounder of the project and a senior program manager at Google Earth Outreach. Crucially, Global Fishing Watch makes its data open to anyone­­­—so now the National Geographic Society is using it to lobby for new marine preserves, and governments and nonprofits use it to target illicit fishing.

If we want better environmental data, we’ll need for-profit companies with the expertise and high-end sensors to pitch in too. Planet, a firm with an array of 140 satellites, takes daily snapshots of the entire Earth. Customers like insurance and financial firms love that sort of data. (It helps them understand weather and climate risk.) But Planet also offers it to services like Global Forest Watch, which maps deforestation and makes the information available to anyone (like activists who help bust illegal loggers). Meanwhile, Google’s skill in cloud-based data crunching helps illuminate the state of surface water: Google digitized 30 years of measurements from around the globe—extracting some from ancient magnetic tapes—then created an easy-to-use online tool that lets resource-poor countries figure out where their water needs protecting.

Tech can empower ordinary people too. To tackle the marine litter mystery, Eriksen and other antipollution groups built an app that hundreds of volunteers used to map the banks of the Los Angeles River, where trash was entering the marine ecosystem. Now cities can use that data to do surgical interventions, like identifying hot spots that need more trash cans or more frequent cleanup.

“It’s totally scalable,” Eriksen says, and groups from Ecuador to Hawaii plan to use the app for their own surveys. The citizen-­involvement angle has serious legs: In China, 300 million people use an app made by Alipay that lets them donate money to plant forests and then monitor their growth via satellite and land-camera imagery. (They’ve planted over 13 million trees already.) This participation by everyday folks, as Jensen argues, builds crucial political support for environmental action.

Now, I don’t want to soft-pedal the task at hand. We’re way behind where we should be on nearly every environmental goal. But for once, tech offers a rare all-good-news story. When you’re fumbling around in the dark, the first step is to turn on the lights.