Sewage Is A Biological Necessity, And A Methane Minefield

In most cities, once you flush a toilet, the water and waste flows through the sewage system to a water treatment plant. Once it’s there, it goes through a series of chemical and biological processes which clean it up and make the water safe to drink again. But a recent paper in the journal Environmental Science & Technology finds that some of those sewage plants may be having a greater impact on the climate than previously thought.

The anaerobic decomposition of organic material in the waste stream at sewage plants produces methane, a potent greenhouse gas. The researchers used an electric car fitted with a suite of atmospheric gas sensors to sniff the emissions downwind of 63 sewage treatment plants at different times and during different seasons. They found that the wastewater treatment process may release amounts of methane nearly twice that estimated by the Intergovernmental Panel on Climate Change and the U.S. Environmental Protection Agency. In a related study, other researchers analyzed data from published monitoring of wastewater treatment facilities around the globe—and arrived at a similar estimate of the methane production.

Mark Zondlo, a professor of civil and environmental engineering at Princeton University, and one of the authors of the methane-sniffing research, talks with guest host Shahla Farzan about the studies, and about what might be done to mitigate the methane impact of treating our cities’ sewage.

Meet The Activist Reimagining Climate Education

As a high school student, Sage Lenier remembers being frustrated with the way she was taught about climate change. It left her feeling helpless, contending with the gloomy predictions for a doom-filled future. Despite talking about the problems, she wasn’t learning anything about solutions. A year later at the University of California, Berkeley, Sage took it upon herself to create the course she wished she had—one focused on solutions and hope. Nearly 2,000 students have taken her course since, and she recently founded Sustainable & Just Future, a youth-led educational non-profit. Guest host Kathleen Davis talks with Sage about her experiences, why we’ve gotten climate education all wrong, and how we need to be thinking about our future.

The First Fully Mapped Animal Brain Is The Larva Of A Fruit Fly

Understanding how a brain works is one of the most challenging tasks in science. One of the ultimate goals in brain research is to develop brain maps, which catalog which neurons are connected to others, and where. If researchers have a brain map, they can better understand neurological conditions like addiction, and develop more effective treatments. It may even help scientists understand more abstract concepts, like consciousness. The catch? Mapping millions, or even billions, of tiny little neurons is an extremely challenging and expensive task.

But a team of researchers at Johns Hopkins University recently completed a 12-year effort to map the entire brain of a fruit fly larva, which is the size of a grain of salt, and contains 3,000 neurons and 500,00 connections. Their results were published in the journal Science. Joining guest host Shahla Farzan is the paper’s senior author Joshua Vogelstein, an associate professor of biomedical engineering at Johns Hopkins University. They talk about how exactly his team completed this task, when a human brain map might be completed, and how this could be a meaningful step in understanding how enlightenment works.

National Audubon Society Sticks With Its Name, Despite Namesake’s Racism

For more than a year, the National Audubon Society—one of the largest bird conservation groups—mulled over a big decision: whether or not they should rename the organization. Its namesake, John James Audubon, is known as the founding father of American birding. But Audubon and his family were anti-abolition and they enslaved nine people in their home. He also actively harmed and looted from Indigenous people. Earlier this month, the National Audubon Society announced its decision to keep “Audubon” in its name, saying that it’s important in allowing the organization to keep protecting birds. The open letter also says the organization represents “much more than the work of one person.”

The decision to stick with the Audubon name has been met with intense backlash, from birders, local branches, and even its own employees. A handful of locally-run Audubon branches, from New York City to Madison, Wisconsin, plan to change their names to nix the word Audubon. Seattle’s branch is renaming itself “Birds Connect Seattle,” and Washington D.C.’s Audubon Naturalist Society is now “Nature Forward.” Guest host Kathleen Davis speaks with Stuart Wells, executive director of Portland Audubon and conservation scientist Corina Newsome about their reactions to the National Audubon Society keeping its name, and how changes are happening locally, including in places like Portland.

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

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