Humankind is facing an imminent threat of extinction, according
to new research released on Wednesday by the science journal Nature.
The report
Approaching a state shift in Earth’s biosphere
reveals that our planet's biosphere is steadily approaching a 'tipping
point', meaning all ecosystems are nearing sudden and irreversible
change that will not be conducive to human life.
"We have reason to believe the change may be abrupt and surprising,"
said co-researcher Arne Mooers, a professor of biodiversity at Simon
Fraser University in Canada's British Columbia. (Photo: Image Science
& Analysis Laboratory , NASA Johnson Space Center) The
authors describe what they see as a fast paced 'state shift' once the
tipping point is reached, which contrasts with the mainstream view that
environmental change will take centuries. "It's a question of whether it
is going to be manageable change or abrupt change. And we have reason
to believe the change may be abrupt and surprising," said co-researcher
Arne Mooers, a professor of biodiversity at Simon Fraser University in
Canada's British Columbia.
"The data suggests that there will be a reduction in biodiversity and
severe impacts on much of what we depend on to sustain our quality of
life, including, for example, fisheries, agriculture, forest products
and clean water. This could happen within just a few generations,"
stated lead author Anthony Barnosky, a professor of integrative biology
at the University of California in Berkeley.
"My colleagues who study climate-induced changes through the Earth's
history are more than pretty worried," he said in a press release. "In
fact, some are terrified," said co-researcher Arne Mooers, a professor
of biodiversity at Simon Fraser University in Canada's British Columbia.
The report, written by 22 scientists from three continents ahead of
this year's Rio+20 summit, claims that the 'state shift' is likely;
however, humans may have a small window to curb over-consumption,
over-population growth and environmental destruction, with drastic
efforts to change the way we live on planet earth through international
cooperation.
* * *
Agence France-Presse:
Environmental collapse now a serious threat: scientists
Climate change, population growth and environmental destruction could
cause a collapse of the ecosystem just a few generations from now,
scientists warned on Wednesday in the journal Nature.
The factors in today's equation include a
world population that is set to rise from seven billion to around 9.3
billion by mid-century and global warming that will outstrip the UN
target of two degrees Celsius (3.6 degrees Fahrenheit).
The paper by 22 top researchers said a "tipping point" by which the
biosphere goes into swift and irreversible change, with potentially
cataclysmic impacts for humans, could occur as early as this century.
[...]
The Nature paper, written by biologists, ecologists, geologists and
palaeontologists from three continents, compared the biological impact
of past episodes of global change with what is happening today.
The factors in today's equation include a world population that is
set to rise from seven billion to around 9.3 billion by mid-century and
global warming that will outstrip the UN target of two degrees Celsius
(3.6 degrees Fahrenheit).
The team determined that once 50-90 percent of small-scale ecosystems
become altered, the entire eco-web tips over into a new state,
characterised especially by species extinctions.
Once the shift happens, it cannot be reversed.
To support today's population, about 43 percent of Earth's ice-free
land surface is being used for farming or habitation, according to the
study.
On current trends, the 50 percent mark will be reached by 2025, a
point the scientists said is worryingly close to the tipping point.
If that happened, collapse would entail a shocking disruption for the
world's food supply, with bread-basket regions curtailed in their
ability to grow corn, wheat, rice, fodder and other essential crops.
"It really will be a new world, biologically, at that point," said
lead author Anthony Barnosky, a professor of integrative biology at the
University of California in Berkeley.
* * *
Montreal Gazette:
Earth reaching an environmental 'state shift': Report
Or, as Canadian co-author Arne Mooers, at Simon Fraser Univeristy in
British Columbia, puts it: "Once the shift occurs, they'll be no going
back."
The "ultimate effects" of a state shift are
unknown, but the researchers suggest it could have severe impact on the
world's fisheries, agriculture, forests and water resources. And they
warn that "widespread social unrest, economic instability and loss of
human life could result."
A shift or tipping point is "speculation at this point," Mooers told Postmedia News.
"But it's one of those things where you say: 'Hey, maybe we better find out,' because if it's true, it's pretty serious." [...]
The climate is warming so fast that the "mean global temperature by
2070 (or possibly a few decades earlier) will be higher than it has been
since the human species evolved," they say.
And to support the current population of seven billion people, about
43 per cent of Earth's land surface has been converted to agricultural
or urban use. The population is expected to hit nine billion by 2045 and
they say current trends suggest that half Earth's land surface will be
altered by humans by 2025.
That's "disturbingly close" to a potential global tipping point,
Barnosky says in a release issued with the report. The study says
tipping points tend to occur when 50 to 90 per cent of smaller
ecosystems have been disrupted.
"I think that if we want to avoid the most unpleasant surprises, we
want to stay away from that 50 per cent mark," Barnosky says.
The "ultimate effects" of a state shift are unknown, but the
researchers suggest it could have severe impact on the world's
fisheries, agriculture, forests and water resources. And they warn that
"widespread social unrest, economic instability and loss of human life
could result."
* * *
Live Science:
Tipping Point? Earth Headed for Catastrophic Collapse, Researchers Warn
Barnosky and his colleagues reviewed research on climate change,
ecology and Earth'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 its present, 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.
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