Some of America’s top left-leaning publications are sounding alarm bells after release of a “terrifying” report warning that global warming and overpopulation will soon lead to “mass extinctions” of humanity.

“The situation ‘scares the h– out of me,’ said one author of the [report],” writes “green” blogger Justin Gillis of the New York Times. “‘We’ve created this enormous bubble of population and economy. … It’s either got to be deflated gently, or it’s going to burst.'”

Alexander Abad-Santos of The Atlantic’s “Wired” blog also wrote about the report, which was published in the scientific journal Nature earlier this week, in an entry called “The World as We Know It Is About to End, Say Some Really Frightened Scientists.”

“A new study by 22 biologists and ecologists has found that environmental changes on our planet are reaching a point of no return that leads to mass extinctions,” writes Abad-Santos. “And as The Atlantic’s James Fallows, who pointed out this terrifying study to us, writes, this could be the most important news of 2012.”

The Atlantic then refers back to the Times, quoting: “How soon do these scientists expect the world as we know it to end? Gillis writes, ‘within a few human generations, if not sooner.'”

The heart of the scientists’ claim, as Gillis explains it, is that humans have used up 43 percent of the ice-free land surface on earth, and if that number tops 50 percent, “the ecological web can collapse.”

Gillis concedes that the 22 authors of the report “will be accused of alarmism” and reveals the scientists admitted some of their conclusions are based on guesswork. Nonetheless, Gillis insists, the report comes at an important time for international, political action on “global warming.”

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“In interviews, scientists involved in writing the paper acknowledged that the 50 percent threshold was simply a best guess, based on extrapolating the earlier research,” Gillis writes. “But they said they were deeply concerned about many of the trends on the planet and the seeming inability of the world’s political leadership to grapple with them.”

Gillis then explains the paper was released as part of a package leading up to Rio+20, a “global sustainability summit” held in Rio de Janeiro, 20 years after the “Earth Summit,” a nickname for the United Nations Conference on Environment and Development, held in Rio in 1992.

“At the so-called Earth Summit in Rio 20 years ago, the nations of the world ostensibly committed themselves to broad actions to improve the environmental situation as well as reduce risks to human society,” Gillis writes. “Expectations for the Rio+20 conference, meant as a follow-up to the original, are low, but many environmental groups are pushing for action.”

The first Earth Summit is famous for launching a controversial United Nations action plan called “Agenda 21,” which was labeled by a Republican National Committee resolution earlier this year as “a comprehensive plan of extreme environmentalism, social engineering and global political control.”

“This United Nations Agenda 21 plan of radical so-called ‘sustainable development,'” the RNC resolution insists, “views the American way of life – of private property ownership, single family homes, private car ownership and individual travel choices, and privately owned farms – all as destructive to the environment.”

The resolution describes Agenda 21 as a scheme for the “socialist/communist redistribution of wealth” that deems national sovereignty not only an impediment to its goals, but also “a social injustice.”

“The Republican National Committee recognizes the destructive and insidious nature of United Nations Agenda 21,” the resolution concludes, “and hereby exposes to the public and public policy makers the dangerous intent of the plan.”

Regardless of whether Rio+20 is best described as another phase of Agenda 21’s globalist political agenda or a simply a call to responsible environmentalism, the authors of the report insist their findings demand the world act before it’s too late.

Anthony Barnosky, one of the report’s authors and a professor of Integrative Biology associated with the Berkeley Initiative in Global Change Biology, says, “It’s pretty clear we’re heading for something big.”

In the following video, Barnosky can be seen explaining some of the ramifications of his group’s findings and proclaiming, “We’re at a point in humanity’s history when we need to plan for the future, to plan for the long term and drive the planet in directions that we want it to go.”

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