Earth Tipping Point Study In Nature Journal Predicts Disturbing And Unpredictable Changes


This composite image uses a number of swaths of the Earth’s surface taken on January 4, 2012.

By Stephanie Pappas, LiveScience Senior Writer
Earth is rapidly headed toward a catastrophic breakdown if humans don’t get their act together, according to an international group of scientists.

Writing Wednesday (June 6) in the journal Nature, the researchers warn that the world is headed toward a tipping pointmarked by extinctions and unpredictable changes on a scale not seen since the glaciers retreated 12,000 years ago.

“There is a very high possibility that by the end of the century, the Earth is going to be a very different place,” study researcher Anthony Barnosky told LiveScience. Barnosky, a professor of integrative biology from the University of California, Berkeley, joined a group of 17 other scientists to warn that this new planet might not be a pleasant place to live.

“You can envision these state changes as a fast period of adjustment where we get pushed through the eye of the needle,” Barnosky said. “As we’re going through the eye of the needle, that’s when we see political strife, economic strife, war and famine.” [Top 10 Ways to Destroy Earth]


The danger of tipping

Barnosky and his colleagues reviewed research on climate change, ecology andEarth’s tipping points that break the camel’s back, so to speak. At certain thresholds, putting more pressure on the environment leads to a point of no return, Barnosky said. Suddenly, the planet responds in unpredictable ways, triggering major global transitions.

 The most recent example of one of these transitions is the end of the last glacial period. Within not much more than 3,000 years, the Earth went from being 30 percent covered in ice to itspresent, nearly ice-free condition. Most extinctions and ecological changes (goodbye, woolly mammoths) occurred in just 1,600 years. Earth’s biodiversity still has not recovered to what it was.

Today, Barnosky said, humans are causing changes even faster than the natural ones that pushed back the glaciers — and the changes are bigger. Driven by a 35 percent increase in atmospheric carbon dioxide since the start of the Industrial Revolution, global temperatures are rising faster than they did back then, Barnosky said. Likewise, humans have completely transformed 43 percent of Earth’s land surface for cities and agriculture, compared with the 30 percent land surface transition that occurred at the end of the last glacial period. Meanwhile, the human population has exploded, putting ever more pressure on existing resources. [7 Billion Population Milestones]

“Every change we look at that we have accomplished in the past couple of centuries is actually more than what preceded one of these major state changes in the past,” Barnosky said.


Backing away from the ledge

The results are difficult to predict, because tipping points, by their definition, take the planet into uncharted territory. Based on past transitions, Barnosky and his colleagues predict a major loss of species (during the end of the last glacial period, half of the large-bodied mammal species in the world disappeared), as well as changes in the makeup of species in various communities on the local level. Meanwhile, humans may well be knotting our own noose as we burn through Earth’s resources.

“These ecological systems actually give us our life support, our crops, our fisheries, clean water,” Barnosky said. As resources shift from one nation to another, political instability can easily follow.

Pulling back from the ledge will require international cooperation, Barnosky said. Under business-as-usual conditions, humankind will be using 50 percent of the land surface on the planet by 2025. It seems unavoidable that the human population will reach 9 billion by 2050, so we’ll have to become more efficient to sustain ourselves, he said. That means more efficient energy use and energy production, a greater focus on renewable resources, and a need to save species and habitat today for future generations.

“My bottom line is that I want the world in 50 to 100 years to be at least as good as it is now for my children and their children, and I think most people would say the same,” Barnosky said. “We’re at a crossroads where if we choose to do nothing we really do face these tipping points and a less-good future for our immediate descendents.”


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How not to change a climate sceptic’s mind

The Pandemic of Consumerism

HOW do you get your point across over an issue as contentious as climate change? As a hearing in the US Congress last week showed, the evidence alone is not enough.

At issue was the authority of the Environmental Protection Agency to regulate greenhouse gas emissions. Republicans in the House and Senate are backing bills that would strip the EPA of that right, which is based on findings that rising carbon dioxide levels pose a threat to health and the environment.

At the hearing, House Democrats hoped to counter these moves by calling a cast of climatologists to explain the weight of scientific evidence for climate change. A meeting of minds it was not. The effort seemed only to harden Republican scepticism.

For Dan Kahan of the Cultural Cognition Project at Yale University, the result was predictable. He has previously shown that simply explaining the science behind contentious issues drives the two sides further apart. But Kahan’s work also suggests how warring parties can move towards consensus.

Kahan grades people on two scales of cultural belief: individualists versus communitarians, based on the different importance people attach to the public good when balanced against individual rights; and hierarchists versus egalitarians, based on their views on the stratification of society. Republicans are more likely to be hierarchical-individualist, while Democrats are more often egalitarian-communitarian.

People’s views on contentious scientific issues tend to reflect their position on these scales. For example, egalitarian-communitarians tend to accept the evidence that climate change is a threat, while hierarchical-individualists reject it.

Yet people’s views do change if the right person is offering the evidence. Kahan investigated attitudes for and against giving the human papillomavirus (HPV) vaccine to schoolgirls to prevent cervical cancer – another divisive issue. After he presented people with both sides of the argument, he found that 70 per cent of egalitarian-communitarians thought it was safe, compared with 56 per cent of hierarchical-individualists.

When the “pro” argument was presented as coming from an expert painted as being in the egalitarian-communitarian camp, and the “anti” view came from a hierarchical-individualist, the split widened to 71 versus 47 per cent. But strikingly, swapping the experts around caused a big shift: 61 per cent of hierarchical-individualists then rated the vaccine as safe, compared to 58 per cent of egalitarian-communitarians. In short, evidence from someone you identify with sways your view.

In practice, it is hard to find experts who will give “unexpected” testimony. But when the evidence was presented by experts with a variety of backgrounds, views were not so starkly polarised, with 65 per cent of egalitarian-communitarians and 54 per cent of hierarchical-individualists agreeing that the vaccine is safe.


The Pandemic of Consumerism

The Pandemic of ConsumerismSPECIAL CLIMATE CHANGE ISSUE "To Protect Succeeding Generations"

Periods of global warming are not in and of themselves a human invention. But humans have invented ways of turning a natural cycle into an abnormality whose severity can exceed the tragedy of one atomic bomb or even of several atomic bombs. However, we cannot see the explosion because we live in it, because it seems to be an evident freak of nature to which we must all resign ourselves.

The world’s governments are too busy trying to save humanity from the “great crisis” —the economic crisis— by stimulating the same consumption that is leading us to unmitigated disaster. If the level of global destruction has not yet reached the dreaded status of full-blown catastrophe, it is only because consumerism has not yet reached its supposedly desired levels.

In this collective delusion, development is confused with consumerism, wastefulness with success, and growth with fattening. The pandemic is considered a sign of good health. Its “success” has been so overwhelming that there is no ideology or political system in the world that is not bent upon reproducing and multiplying it.

New technologies could help to reduce carbon dioxide emissions, but it is unlikely that this would be sufficient in a world that is just at the beginning of its capacity to consume, to squander, and to destroy. Trying to reduce environmental pollution without reducing consumerism is like combatting drug trafficking without reducing the drug addiction.

Wasteful and irrational consumerism has no limits; it has not prevented the death of millions of children from hunger, but it has endangered the existence of the entire biosphere. If “successful” consumerism is not replaced by the forgotten values of austerity, soon we will choose between war and misery, hunger and epidemics.

It is in hands of governments and in hands of each of us either to organize the salvation or accelerate the destruction of our own world. The Climate Change Conference in Copenhagen is a new opportunity to prevent the greatest calamity humanity has ever faced. Let us not have another opportunity missed, because we certainly do not have all the time in the world.

Jorge Majfud

August 2009

Lincoln University

UN Chronicle >>

UN Chronicle Review. Special Climate Change Issue.