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Today on the program, we have a look at what's called regenerative farming and how applying those practices to raising cattle may or may not help counter climate change. Right now, though, the 800-pound bull in the room. Cities around the world are responsible for 70% of planet-warming gas emissions, mostly from transportation and keeping buildings comfortable.
As cities try to change things to prevent the worst effects of climate change, they need a reliable way to check their progress. Here in the U.S., that's typically done with estimations published just once a year and which researchers have found may be too low. Well, scientists at UC Berkeley are now pitching a new way to track emissions in the same way smog is tracked - in real time using sensors. Member station KQED's Kevin Stark got up close and personal with a CO2 sensor in the Bay Area.
KEVIN STARK, BYLINE: I'm assuming - are we going up this ladder here?
NAOMI ASIMOW: We're going up this ladder, yeah.
STARK: Here, you go first.
I'm climbing onto the roof of a research building near UC Berkeley's campus with Naomi Asimow. She's a graduate student studying climate change, which is mainly driven by carbon dioxide from human activity.
ASIMOW: Our job as researchers is to figure out where that CO2 is coming from.
STARK: It's invisible to the naked eye but detectable in concentration by sensors like the one right here. Asimow points to a white cylinder. It's the size of a small thermos.
All right, wow. Look at this in here. So tell me about what's inside here.
ASIMOW: A little mini circuit board, and it has an SD card in it that's collecting the data.
STARK: This device is part of a network of sensors on roofs around the bustling Bay Area. In order to meet its climate goals, the U.S. uses expensive research towers to provide a zoomed-out national picture of CO2 emissions. But cities also need more specific information to know if they're meeting their individual climate goals. Right now, oil refineries, for example, or other industrial facilities, report how much fuel they use to regulators, who then calculate their emissions based on the average of what would be contained in a gallon of gasoline. Asimow says her sensors could be useful to cities by providing constant granular feedback that may be more accurate.
ASIMOW: My dream is that there's a ground-based network like this in every city and that cities can reliably quantify their emissions.
STARK: Cities could place these sensors downwind of one of those refineries to monitor if the emissions are as expected. This way, they could see if a company under-reports or if equipment is leaching greenhouse gas into the atmosphere that would otherwise be missed. Many cities already use sensors to track different kinds of pollution, like smog. Daniel Hamilton is Oakland's sustainability director.
DANIEL HAMILTON: Getting these sensors in place in as many places as possible will help us identify where the hot spots are so that we can take action.
STARK: He says the impacts can vary down to the block level. Cities could use the CO2 sensors in a similar way.
HAMILTON: Sensors have a huge role to play in this because we're understanding more that localized impacts are really important in terms of setting policy.
STARK: But air regulators point out that they aren't perfect. David Ridley studies emerging technology for the California Air Resources Board. He says they can be imprecise, although...
DAVID RIDLEY: There's strength in numbers that you can deploy 50-plus of these sensors across a wider area, and then if you've got careful calibration and quality control, you can start to then see patterns.
STARK: If regulators place the sensors along highways, for example, and they find CO2 concentrations are consistently higher than they expect, then they know their estimates are wrong. That could lead to a better understanding of their carbon footprint. Los Angeles, Providence, R.I., and Glasgow, Scotland, are using Berkeley's network, and the White House says they want to adopt these kinds of sensors as part of a national monitoring system.
For NPR News, I'm Kevin Stark in San Francisco. Transcript provided by NPR, Copyright NPR.
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