Google

In the next decade or so, more than 6,000 cities, states, and provinces around the world will try to do something that has eluded humanity for 25 years: reduce their emissions of greenhouse gases, which warm the atmosphere and cause climate change.

The city-level leaders overseeing this task won’t have the same tools available to their national peers. Most of them won’t have an Environmental Protection Agency (or its equivalent), a meteorological bureau, a team of military engineers, or NASA. So where will they start? Never mind how to reduce their city’s greenhouse-gas emissions; how will they know what’s spewing carbon dioxide in the first place?

Maybe Google will do it for them. Or, at least, do it with them.

Google has started estimating greenhouse-gas emissions for individual cities, part of what it recently described as an ambitious new plan to deploy its hoard of geographic information on the side of climate-concerned local leaders.

“The first step toward taking climate action is creating an emissions inventory,” says Saleem Van Groenou, a program manager at Google Earth. “Understanding your current situation at the city scale, and understanding what you can do to it—that’s an information problem, and that’s a good place for Google to sit.”

So far, the company has only released estimates for five cities, including Pittsburgh, Buenos Aires, and Mountain View, California. It plans to expand the program gradually to cover municipalities worldwide, but has declined to provide more specific plans. “What we envision is an open search bar for users to search for their own city in the future,” Van Groenou told me.

As part of this initiative, Google says it will also release its proprietary estimates of a city’s annual driving, biking, and transit ridership, generated from information collected by its popular mapping apps, Google Maps and Waze. The company has never released this kind of aggregate transportation data to the public before, and it says it may share even more specific types of data with individual local governments.

“This information has historically been really hard to get a hold of,” Van Groenou said. “But this is precise data, like looking at the ‘red-yellow-green’ traffic in Google Maps and aggregating it up for an entire year.”

Google made the announcement earlier this month as part of the Global Climate Action Summit in San Francisco. The summit, organized in part by California Governor Jerry Brown, was meant to encourage states and cities that have advanced climate policy since President Donald Trump took office. These local programs do much, but they have not replaced climate policies revoked by Trump: A recent report from Yale and a number of European think tanks found that these “subnational” programs could make up about half of the United States’ pledged carbon cuts under the Paris Agreement.

Google has framed the new project, called the Environmental Insights Explorer, as a way for leaders to focus and improve local climate programs.

The explorer remains a better tool for getting a glancing sense of a city’s carbon emissions than it is for making meticulous policy. Right now, it can only estimate carbon emissions from electricity and transportation—two important sources of pollution, but not the only ones. Heavy industry and agriculture, for instance, generate roughly a third of U.S. emissions. Google is also hampered by the age and quality of some data: To estimate how much carbon is emitted to power a given city, it must use a six-year-old data set from the EPA.

But it can still provide useful information. In Pittsburgh, for instance, it estimates that the power grid drives more than three times the emissions as the transportation sector. The situation is reversed in Buenos Aires, where cars and trucks produce twice the pollution created by the electricity grid.

“This is not sufficient information to decide whether to build another tunnel underneath the Hudson. We don’t know that yet. But we can say that in Buenos Aires, you should probably focus on transportation as opposed to building emissions,” Van Groenou said.

The tool can further help would-be city planners imagine a more eco-friendly city. If Pittsburghers took an extra 1 million trips a year by bike instead of by car, they would prevent almost 700,000 tons of carbon dioxide from spewing into the atmosphere. The project also integrates some data from Project Sunroof, a Google program that aims to make it easier to install rooftop solar panels.

Local governments may be most excited about Google’s plan to release some ridership data. This will be the first time that Google has publicly estimated how many car trips occur to, from, or within a city every year. (There are about 547 million total in Pittsburgh.)

Mike Gardner-Sweeney, the transportation director for the city of Boulder, Colorado—one of the few cities in the country with a carbon tax—said there was “definitely a lot of interest” from municipal managers in getting this type of Google data. Though Boulder uses a variety of technologically advanced methods to estimate travel time, the Google Maps and Waze data would augment both its real-time and more long-term sense of road use, he said. (Boulder is not working with Google at the moment.)

The EPA prepares the gold-standard estimates of greenhouse-gas emissions for the United States. But these figures do not extend to the local level. Google is “not here to compete with the EPA in any way,” Van Groenou said. In fact, the company cannot duplicate U.S.-level carbon estimates right now, because it would double-count all trips between two municipalities. But Van Groenou told me he hopes that Google can help cities better understand their own climate situation—particularly since having a shared method of estimating emissions would let cities in different countries compare their climate policies.

“The bottom line is that this is not something that Google can do alone,” Van Groenou said. “This is a communal thing. This is something we have to come together to make any change on.”

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