Global tipping point not backed by science, study finds

Feb 28, 2013

(Phys.org)—A group of international ecological scientists led by the University of Adelaide have rejected a doomsday-like scenario of sudden, irreversible change to the Earth's ecology.

In a paper published today in the journal Trends in , the scientists from Australia, US and UK argue that global-scale ecological are unlikely and that over large areas seem to follow a more gradual, smooth pattern.

This opposes recent efforts to define 'planetary tipping points' - critical levels of biodiversity loss or land-use change that would have global effect - with important implications for science and policy-makers.

"This is good news because it says that we might avoid the doom-and-gloom scenario of abrupt, irreversible change," says Professor Barry Brook, lead author of the paper and Director of at the University of Adelaide. "A focus on planetary tipping points may both distract from the vast ecological transformations that have already occurred, and lead to unjustified about the catastrophic effects of tipping points.

"An emphasis on a point of no return is not particularly helpful for bringing about the conservation action we need. We must continue to seek to reduce our impacts on the without undue attention on trying to avoid arbitrary thresholds."

A tipping point occurs when an ecosystem attribute such as species abundance or responds rapidly and possibly irreversibly to a human pressure like land-use change or climate change.

Many local and regional-level ecosystems, such as lakes and grasslands, are known to behave this way. A planetary tipping point, the authors suggest, could theoretically occur if ecosystems across Earth respond in similar ways to the same human pressures, or if there are strong connections between continents that allow for rapid diffusion of impacts across the planet.

"These criteria, however, are very unlikely to be met in the real world," says Professor Brook. "First, ecosystems on different continents are not strongly connected. Second, the responses of ecosystems to human pressures like climate change or land-use change depend on local circumstances and will therefore differ between localities."

The scientists examined four principal drivers of terrestrial ecosystem change - climate change, land-use change, habitat fragmentation and biodiversity loss - and found they were unlikely to induce global tipping points.

Explore further: The future of global agriculture may include new land, fewer harvests

More information: www.sciencedirect.com/science/… ii/S0169534713000335

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Grallen
2.8 / 5 (8) Feb 28, 2013
Who has been focusing on tipping points? The 2 degree mark was "acceptable losses" by what I understood.

Maybe the was to make it sound new and make people pay attention?

Well, at least the title will attract denialists to an article that doesn't support them.
antialias_physorg
3.8 / 5 (16) Feb 28, 2013
In a paper published today in the journal Trends in Ecology and Evolution, the scientists from Australia, US and UK argue that global-scale ecological tipping points are unlikely and that ecological change over large areas seem to follow a more gradual, smooth pattern.

As long as there are buffer systems (ice caps, oceanic concentration of carbonic acid, etc.) you get smooth changes. But buffer systems do have limits. So OF COURSE do we currently see smooth changes because the buffer systems have (thankfully) not reached their limits yet.

It's like a bucket - as long as you have space in a bucket nothing spills. But as soon as the bucket is full spillage jumps from 0 to 100%.
Disproselyte
3.5 / 5 (11) Feb 28, 2013
Precisely, and what about changing patterns in the global ocean currents etc. Those changes do impact all ecosystems, and are most likely non linear phenomena. How far can you disturb a near stationary system, until it's dynamical equilibrium bifurcates ireverrsibly via unpredictable processes to unknown and probably undesirable new regimes.
Take care, urgently, because we do not have a second chance and it is definitely a one way ticket.
Infinite Fractal Consciousness
1 / 5 (8) Feb 28, 2013
Who needs bees, anyway.
The Alchemist
1.3 / 5 (7) Mar 01, 2013
@Antialias, however did we get off on the wrong foot?
Awesome! Perfect. I can't agree more! You have stated exactly the environmental change problem.
And part of it is, even though we may see the ant-& arctic ice melting, for example, "it doesn't affect **UhSs**."
Yet...
antialias_physorg
4.5 / 5 (8) Mar 01, 2013
however did we get off on the wrong foot?


Does it matter? I have no problem ripping into someone I agree with on other subjects when they post BS. I also have no problem agreeing with someone who is usually in the "crazy-camp" when they make a post with real substance and valid arguments.

On this site (and in science in general) I judge by content - not person. And that judgement is determined by each post individually.
A_Paradox
2.3 / 5 (3) Mar 01, 2013
Well I would love for these researchers to be right. I think however that the world we now inhabit is different in at least one significant respect from all times past, and that is because our species has discovered scientific method [SM].

SM like all powerful things may have negative results as well as positive. It is up to us to make sure that what transpires is good for everybody, and the only way we can succeed at that is by communicating openly and truthfully.

Points for thought:
1/ I haven't seen any economist say anything helpful about the vast resource of frozen organic matter in the permafrost regions of Eurasia and North America. Are we just going to let them defrost without confining the methane?
2/ USA and other countries want to become independent of Arab controlled oil supplies, so shale oil and gas is to become the 'life saver' of dysfunctional consumer capitalism. Are we going to let 'cheap' fracked gas double the CO2 load of the atmosphere?
Disproselyte
1.5 / 5 (4) Mar 01, 2013
@ A_Paradox: "Communicating openly and truthfully": I totally agree and formulated years ago a

Universal Cybernetic Manifesto

Keep on formulating and publishing your goals.
Keep on discussing and adjusting your goals.
Keep on respecting your engagements.

If you're interested in the motivation for this, have a look to "From Knowledge Integration to Worldview" = METApproach.blogspot.com

Think Globally, Act Consciously!