Tuesday 7 June 2011

Eco-Guardrails: " pLanetary bOundaries "

" We are entering the Anthropocene, a new geological era in which our activities are threatening the earth's capacity to regulate itself. "
- Professor Will Steffen -
-Australian National University (ANU)&ANU Climate Change Institute-

Is it important to designate our epoch as Anthropocene is an ongoing debate and though scientists are divided on the imperative need to baptize our era so, they are not split when it comes to the dire need for recognizing the eco-destruction perpetrated and perpetuated by our species since its ascendancy to dominance in the animal kingdom. Also on the need to search for alternative paradigms to tackle the impending catastrophes if we choose to continue to ride the rollercoaster of indiscriminate consumption of natural resources.

An assembly of 28 leading researchers in a transdisciplinary analysis have proposed that global biophysical boundaries, identified on the basis of the scientific understanding of the earth system, can define a "safe planetary operating space" that will allow humanity to continue to develop and thrive for generations to come. They have identified Earth system processes and potential biophysical thresholds, which, if crossed, could generate unacceptable environmental change for humanity. Their paper 'Rockström et al. A safe operating space for humanity. Nature, 2009" focuses on the alternative paradigm of 'boundaries and thresholds' for a safe operating space for humanity on Earth.

Nine boundaries identified were climate change, stratospheric ozone, land use change, freshwater use, biological diversity, ocean acidification, nitrogen and phosphorus inputs to the biosphere and oceans, aerosol loading and chemical pollution.

"The human pressure on the Earth System has reached a scale where abrupt global environmental change can no longer be excluded. To continue to live and operate safely, humanity has to stay away from critical ‘hard-wired´ thresholds in the Earth´s environment, and respect the nature of the planet's climatic, geophysical, atmospheric and ecological processes," says lead author Johan Rockstrom, Director of the Stockholm Resilience Centre. He opines that as long we do not cross the thresholds, our future is bright; but 'transgressing the planetary boundaries' could be devastating to humanity.


"We are beginning to push the planet out of its current stable Holocene state, the warm period that began about 10,000 years ago and during which agriculture and complex societies, including our own, have developed and flourished. The expanding human enterprise could undermine the resilience of the Holocene state, which would otherwise continue for thousands of years into the future," points out Will Steffen. Our post-Industrial Revolution had expanded human activities on Earth to an unprecedented scale that it has  now 'generated geophysical force equivalent to the great forces of nature' is what scientists reckon as the crux of the matter.

Pointing out that traditional models of casting history of humanity in terms of the rise and fall of great civilizations, wars, and specific human achievements leaves out the important ecological and climate contexts that shaped and mediated these events, co-author Robert Costanza, director of the Gund Institute at the University of Vermont, explains the context of the transdisciplinary framework of planetary boundaries brought forth by the assembly of 28 researchers in Science Daily," Human history and earth system history have traditionally been developed independently, with little interaction among the academic communities. The Nature article provides evidence of the necessities to establish a thorough, long-term historical understanding of the exchange between human societies and the earth system, in order to set standards for safe navigation within planetary boundaries and avoid crossing dangerous thresholds. "

Planetary boundaries is a way of thinking that will not replace politics, economics, or ethics, explained environmental historian Sverker Sörlin of the Stockholm Resilience Centre and the Royal Institute of Technology, Stockholm. "But it will help tell all of us where the dangerous limits are and therefore when it is ethically unfair to allow more emissions of dangerous substances, further reduction of biodiversity, or to continue the erosion of the resource base." 

As 'guardrails', contours of the planetary boundaries as defined by the environmental data are our proactive concepts that help us take meaningful  actions to act safely within boundaries 'at the same securing well-being for all' to quote Professor Sverker Sorlin.
" Transgressing planetary boundaries may be devastating for humanity, but if we respect them we have a bright future for centuries ahead, " cautions Johan Rockstrom.

The group of scientists including Hans Joachim Schellnhuber, Will Steffen, Katherine Richardson, Jonathan Foley and Nobel Laureate Paul Crutzen, have attempted to quantify the safe biophysical boundaries outside which, they believe, the Earth System cannot function in a stable state, the state in which human civilizations have thrived.

The study suggests that three of these boundaries (climate change, biological diversity and nitrogen input to the biosphere) may already have been transgressed. In addition, it emphasizes that the boundaries are strongly connected — crossing one boundary may seriously threaten the ability to stay within safe levels of the others.

Observations of an incipient climate transition include the rapid retreat of summer sea ice in the Arctic Ocean, melting of almost all mountain glaciers around the world, and an increased rate of sea-level rise in the last 10-15 years, says Professor Hans Joachim Schellnhuber - co-author and Director of the Potsdam Institute for Climate Impact Research. "What we now present is a novel framework through which our scientific understanding of the Earth System can potentially be used more directly in the societal decision making process," avers co-author Professor Katherine Richardson of the Earth System Science Center at the University of Copenhagen.

'Planetary Boundaries' concept might not be giving a complete roadmap for now, but reveals the 'thresholds' beyond which our actions would be 'tipping towards the unknown' (to quote the title of the Stockholm Resilinece Centre on the topic). 

" Within these boundaries, humanity has the flexibility to choose pathways for our future development and well-being.  In essence, we are drawing the first — albeit very preliminary — map of our planet´s safe operating zones.  And beyond the edges of the map, we don´t want to go.  Our future research will consider ways in which society can develop within these boundaries — safely, sanely and sustainably,  " says co-author Professor Jonathan Foley, Director of the Institute on the Environment at the University of Minnesota.

Once again top-flight scientists have come together in a bid to not just comprehend the non-linear dynamics of our Earth's ecosytem vis a vis humanity's actions, but attempt to weave a pattern of solutions that would in the long run enable resiliency of environmental and ecological sustainability on Earth.

TxtRef: Rockström et al. A safe operating space for humanity. Nature, 2009; DOI: 10.1038/461472a 
http://www.sciencedaily.com/releases/2009/09/090923143339.htm
Scientists Outline 'Safe Operating Space' for Humanity, ScienceDaily, Sept.24/2009.
http://www.stockholmresilience.org/planetary-boundaries


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