Justin Gillis, the New York Times' alarmist environmental reporter, was at it again in a post to the paper's "Green" blog, "Are We Nearing a Planetary Boundary? [1]" 
Gillis's preoccupation with the alleged dangers of overpopulation and overuse of natural resources are reminscent of the alarmism created by Paul Erlich's book The Population Bomb, which notoriously predicted in 1968 that 65 millions Americans would die of starvation in the 1970s (more like dieting).
Gillis, a true believer, proudly admitted his "climate change" activism in an April interview [2] with the Columbia Journalism Review. His Wednesday worrying was based on a new report from the environmental journal Nature.
The earth could be nearing a point at which sweeping environmental changes, possibly including mass extinctions, would undermine human welfare, 22 prominent biologists and ecologists warned on Wednesday.
Acknowledging in a new paper that both the likelihood and timing of such a planetary “state shift” were uncertain, the scientists nonetheless described warning signs that it could arrive within a few human generations, if not sooner.
The problems are familiar by now: they include a planetary warming that, while slow on the scale of a human lifetime, is extremely rapid on a geologic time scale, the scientists said. And human population growth and economic expansion continue to demand new resources like energy and food, to claim new land and to cut natural landscapes into disconnected patchworks.
Humans have already converted about 43 percent of the ice-free land surface of the planet to uses like raising crops and livestock and building cities, the scientists said. Studies on a smaller scale have suggested that when more than 50 percent of a natural landscape is lost, the ecological web can collapse. The new paper essentially asks, what are the chances that will prove true for the planet as a whole?
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. 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 explained that the article is one of a package from "the journal Nature as part of the lead-up to Rio+20, a global sustainability summit meeting in Rio de Janeiro." He defensively admitted that apocalypse skeptics would accuse the paper's authors of "alarmism," then supported the group's findings.
The United States has taken only minimal steps on climate change, for instance, and global emissions have soared, not fallen, in the 20 years since the Earth Summit. 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 Nature special issue was under wraps until Wednesday afternoon, and most scientists have not seen it yet. Based on history, there is little doubt that the authors of the new paper about a planetary “state shift” will be accused of alarmism.
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Yet the authors marshal clear examples of ecological disasters that have already had serious effects on human society: the collapse of cod fisheries in the North Atlantic, for instance, and the outbreaks of mountain pine beetles that are devastating forests in the West. As humans continue to push planetary limits, are we due for a lot more of this sort of thing, and on a broader scale?