Thousands of scientists issue bleak ‘second notice’ to humanity

In late 1992, 1,700 scientists from around the world issued a dire “warning to humanity.” They said humans had pushed Earth’s ecosystems to their breaking point and were well on the way to ruining the planet. The letter listed environmental impacts like they were biblical plagues — stratospheric ozone depletion, air and water pollution, the collapse of fisheries and loss of soil productivity, deforestation, species loss and catastrophic global climate change caused by the burning of fossil fuels.

“If not checked,” wrote the scientists, led by particle physicist and Union of Concerned Scientists cofounder Henry Kendall, “many of our current practices put at serious risk the future that we wish for human society and the plant and animal kingdoms, and may so alter the living world that it will be unable to sustain life in the manner that we know.”

But things were only going to get worse.

To mark the letter’s 25th anniversary, researchers have issued a bracing follow-up. In a communique published Monday in the journal BioScience, more than 15,000 scientists from 184 countries assess the world’s latest responses to various environmental threats. Once again, they find us sorely wanting.

“Humanity has failed to make sufficient progress in generally solving these foreseen environmental challenges, and alarmingly, most of them are getting far worse,” they write.

This letter, spearheaded by Oregon State University ecologist William Ripple, serves as a “second notice,” the authors say: “Soon it will be too late to shift course away from our failing trajectory.”

Global climate change sits atop the new letter’s list of planetary threats. Global average temperatures have risen by more than half a degree Celsius since 1992, and annual carbon dioxide emissions have increased by 62 percent.