Rendering Greenhouse Gases Visible

Through datamining, modeling, and top-down measurement, scientists can pinpoint climate change actors

2 min read
Rendering Greenhouse Gases Visible

Natural gas has no odor, but you can smell a leak thanks to the addition of an odorific mercaptam compound. Do carbon dioxide and other similarly odorless greenhouse gases (GHGs) require some analogous device to make their presence known and thus prompt evasive action? Yes, and for these ubiquitous gases, it will be a visual cue indicating the source and quantity of GHGs.

Consider the software unveiled this month by researchers at Arizona State University, which estimates GHG emissions in cities at the level of individual road segments and buildings. According to their report in the journal Environmental Science and Technology, the system mines public databases for broader statistics on energy use, local air pollution and traffic flows, then feeds those to traffic simulators and a set of building-by-building energy-consumption models. The resulting high-resolution maps present GHG emissions in a format that's both useful to policymakers  and comprehensible to the public.

“Cities have had little information with which to guide reductions in greenhouse gas emissions—and you can’t reduce what you can’t measure,” says Kevin Gurney, a senior scientist with ASU's Global Institute of Sustainability. “We can provide cities with a complete, three-dimensional picture of where, when and how carbon dioxide emissions are occurring.”

So far, maps for Indianapolis are complete and work is ongoing for Los Angeles and Phoenix. Ultimately the scientists hope to map CO2 emissions for all major cities across the United States.

ASU's effort to pinpoint emissions is part of a broader trend that I profiled in July for Earthzine, an online Earth observation journal, earlier this year. I noted a forerunner to ASU's software that has been operating for several years in Finland, where environmental consulting firm Benviroc’s CO2-raportti news portal presents weekly estimates of Finland's emissions by province and, increasingly, by city.

There are also more sophisticated systems that attempt to directly observe rather than estimate localized GHG emissions. Last year, for example, researchers at the Swiss Federal Laboratories for Materials Science and Technology used ground station detection data to model how much trifluoromethane (a gas whose 100-year warming impact is 15 000-times greater than that of CO2) were being released from each country in Western Europe. Their findings differed substantially from the emissions levels reported to the U.N. by several countries; Italy's reports appear to be 10 times too low, likely due to undeclared emissions from a refrigerants factory near Milan.

Such top-down reporting thus does more than simply raise consciousness about sources and causes of GHGs. It provides an independent means of verifying GHG emissions, something that could be critical to reignite diplomatic efforts to control and ultimate drive down GHGs. As ASU's Gurney puts it: “These results may also help overcome current barriers to the United States joining an international climate change treaty.”

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Smokey the AI

Smart image analysis algorithms, fed by cameras carried by drones and ground vehicles, can help power companies prevent forest fires

7 min read
Smokey the AI

The 2021 Dixie Fire in northern California is suspected of being caused by Pacific Gas & Electric's equipment. The fire is the second-largest in California history.

Robyn Beck/AFP/Getty Images

The 2020 fire season in the United States was the worst in at least 70 years, with some 4 million hectares burned on the west coast alone. These West Coast fires killed at least 37 people, destroyed hundreds of structures, caused nearly US $20 billion in damage, and filled the air with smoke that threatened the health of millions of people. And this was on top of a 2018 fire season that burned more than 700,000 hectares of land in California, and a 2019-to-2020 wildfire season in Australia that torched nearly 18 million hectares.

While some of these fires started from human carelessness—or arson—far too many were sparked and spread by the electrical power infrastructure and power lines. The California Department of Forestry and Fire Protection (Cal Fire) calculates that nearly 100,000 burned hectares of those 2018 California fires were the fault of the electric power infrastructure, including the devastating Camp Fire, which wiped out most of the town of Paradise. And in July of this year, Pacific Gas & Electric indicated that blown fuses on one of its utility poles may have sparked the Dixie Fire, which burned nearly 400,000 hectares.

Until these recent disasters, most people, even those living in vulnerable areas, didn't give much thought to the fire risk from the electrical infrastructure. Power companies trim trees and inspect lines on a regular—if not particularly frequent—basis.

However, the frequency of these inspections has changed little over the years, even though climate change is causing drier and hotter weather conditions that lead up to more intense wildfires. In addition, many key electrical components are beyond their shelf lives, including insulators, transformers, arrestors, and splices that are more than 40 years old. Many transmission towers, most built for a 40-year lifespan, are entering their final decade.

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