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Is Earth past the tipping point?

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Biodiversity loss. Land use. Freshwater use. Nitrogen and phosphorus cycles. Stratospheric ozone. Ocean acidification. Climate change. Chemical Pollution. Aerosol loading in the atmosphere.

A team of 30 scientists across the globe have determined that the nine environmental processes named above must remain within specific limits, otherwise the "safe operating space" within which humankind can exist on Earth will be threatened. Amid some controversy, the group has set numeric limits for seven of the nine so far (chemical pollution and aerosol loading are still being pinned down). And the researchers have determined that the world has already crossed the boundary in three cases: biodiversity loss, the nitrogen cycle and climate change.

Jon Foley, director of the University of Minnesota's Institute on the Environment, and a leader of the group, lays out the limits and their implications for human action in an article in Scientific American's April issue.


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He also discusses the issues in a podcast with our own Steve Mirsky.

Foley's team was so moved by the research effort that it put together a compelling video (see below) dramatizing the situation, generated entirely with typography, graphics and energizing music. You can learn more about the team's work at its research site, too.

Mark Fischetti has been a senior editor at Scientific American for 17 years and has covered sustainability issues, including climate, weather, environment, energy, food, water, biodiversity, population, and more. He assigns and edits feature articles, commentaries and news by journalists and scientists and also writes in those formats. He edits History, the magazine's department looking at science advances throughout time. He was founding managing editor of two spinoff magazines: Scientific American Mind and Scientific American Earth 3.0. His 2001 freelance article for the magazine, "Drowning New Orleans," predicted the widespread disaster that a storm like Hurricane Katrina would impose on the city. His video What Happens to Your Body after You Die?, has more than 12 million views on YouTube. Fischetti has written freelance articles for the New York Times, Sports Illustrated, Smithsonian, Technology Review, Fast Company, and many others. He co-authored the book Weaving the Web with Tim Berners-Lee, inventor of the World Wide Web, which tells the real story of how the Web was created. He also co-authored The New Killer Diseases with microbiologist Elinor Levy. Fischetti is a former managing editor of IEEE Spectrum Magazine and of Family Business Magazine. He has a physics degree and has twice served as the Attaway Fellow in Civic Culture at Centenary College of Louisiana, which awarded him an honorary doctorate. In 2021 he received the American Geophysical Union's Robert C. Cowen Award for Sustained Achievement in Science Journalism, which celebrates a career of outstanding reporting on the Earth and space sciences. He has appeared on NBC's Meet the Press, CNN, the History Channel, NPR News and many news radio stations. Follow Fischetti on X (formerly Twitter) @markfischetti

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