With unprecedented levels of carbon dioxide in the atmosphere, widespread species extinction, habit destruction, and increased levels of nitrogen and phosphorous in the oceans courtesy of polluting fertilizers, the Earth is being pushed to the brink and could one day make it unsafe for the continuation of life.  The rate at which humans are destroying the environment is entirely unprecedented, and with such a devastating effect unseen in the last 11,700 years, life is facing an uncertain future ahead.

"The way to interpret this is as a warning sign," professor of zoology at the University of Wisconsin-Madison, Steve Carpenter says. "We're running up to the biophysical boundaries that enable human civilization as we know it to exist."

In 2009, a group of 28 scientists from around the world came together to create the "planetary boundaries framework," which identified nine processes that need to be monitored in order to maintain life on Earth. The processes were: ozone depletion, biodiversity loss, chemical pollution, climate change, ocean acidification, freshwater composition, land systems change, nitrogen and phosphorous flows, and atmospheric aerosol loading. What researchers uncovered was that crossing the recommended thresholds for any of these processes could generate abrupt and possibly irreversible environmental changes.

And now according to researchers, humans have surpassed the safe threshold levels for all four of these boundaries.  Carbon dioxide levels are at historic highs, hovering around 400 parts per million, a level scientists warn is radically altering the atmosphere and oceans.  Approximately 46,000 to 58,000 square miles of forest are decimated each year, with more and more species going extinct at a rate more than 100 times faster than has occurred historically.  

"Within Earth systems, the boundaries are intertwined," Carpenter says.  "For example, phosphorous and nitrogen cause tremendous harm to freshwater resources. We also know that phosphorous and nitrogen affects the carbon cycle."

Kieran Suckling, Executive Director of the Center for Biological Diversity, says that the study is invaluable in conveying the urgency of changing the ways humans interact with the environment to both the public and the politicians.

"Most of the time people think of environmental problems, like species extinction, in linear steps," Suckling says. "You get the impression that you could dial it back at any time and solve all the problems. But this study shows that the problems are not linear. If you inflict enough damage, you've shifted the planet into a whole new state and the damage spirals out of control."

And on top of that, Suckling believes that the report shows that a much more aggressive environmental policy is necessary to mitigate climate change, before it is too late.