“Approaching a State-Shift in Earth’s Biosphere”by Rohit on Sep, 04 2012
A large team of scientists and researchers, many of them from Berkeley, have recently published a landmark paper in the prestigious science journal Nature, entitled “Approaching a State Shift in Earth’s Biosphere.” This is the abstract from the paper:
Localized ecological systems are known to shift abruptly and irreversibly from one state to another when they are forced across critical thresholds. Here we review evidence that the global ecosystem as a whole can react in the same way and is approaching a planetary-scale critical transition as a result of human influence. The plausibility of a planetary-scale ‘tipping point’ highlights the need to improve biological forecasting by detecting early warning signs of critical transitions on global as well as local scales, and by detecting feedbacks that promote such transitions. It is also necessary to address root causes of how humans are forcing biological changes.
At first, this may seem like nothing terribly new; especially at places like Berkeley it seems fairly common knowledge that industrial civilization is steadily pushing global ecology into a very nasty direction. But this notion of a “steady push” is precisely what this paper argues against. The terrifying point being made is that the process of ecological change and human disruption might not be steady at all – and instead, might end up snapping into a radically new state once a certain threshold for disruption is reached.
Ecological state-shifts are almost always accompanied by mass extinctions and a complete overhaul in the food chains and energy balances of the world. The last – which was considered to be one of the more minor state-shifts – occurred at the end of the last Ice Age, a little more than 10,000 years ago, and lead to a collapse in a number of species and a re-organization of environments in the spaces that were no longer covered by glaciers.
But while the state-shift associated with the end of the Ice Age was triggered by the natural variation in the Earth’s orbit, the current changes in Earth’s ecosystems are almost entirely attributed to the continued growth of industrial-capitalist civilization. In addition – and perhaps due to the very fact that the current changes are the result of a sentient species – the rate of change in Earth’s ecology is far more rapid than during any other state-shift in Earth’s multi-billion year history. For example, the withdrawal of the glaciers during the end of the Ice Age took place over several millennia, and this directly changed the composition of about 30% of Earth’s land. But today, human’s have completely taken over and transformed about 43% of Earth’s land, the bulk of which was accomplished in a little over 300 years, ten times faster than the retreat of the glaciers. Other examples of rapid changes caused by humans is the disturbing rate of ocean acidification, and the increase in global temperatures; both of which are caused by carbon emissions, and both of which are occurring faster than during any of the pre-state-shift eras of the past.
All of this leads to a much more drastic picture of ecological changes that we are typically accustomed to seeing in the day-to-day news. As the paper states:
Although the ultimate effects of changing biodiversity and species compositions are still unknown, if critical thresholds of diminishing returns in ecosystem services were reached over large areas and at the same time global demands increased (as will happen if the population increases by 2,000,000,000 within about three decades), widespread social unrest, economic instability and loss of human life could result.
Another important point to note is the idea of reversibility – or lack thereof. In the typical visualization of steady ecological change, one has the notion that the changes are slow, steady, and reversible, and that a few reforms here and there can bring back the ecosystem to the good old days (I would speculate that this is the attitude that drives much of the current apathy toward ecological collapse). However, incorporating state-shift theory means chucking this fantasy of reversibility out the window. Once a state-shift occurs, the new system is the norm. Reversing a state-shift would mean to be able to not only understand, but to engineer the thousands of relationships and feedback cycles that compose the incredibly complex mechanisms of the biosphere, a feat far beyond anything that humanity has ever done or will do in the next few centuries.
In any case, this new type of analysis means that the urgency of re-evaluating and re-structuring our political economy has taken on new dimensions. The time-frame for the rapid destruction of biological systems on Earth has been infused with an unnerving degree of mystery; as the paper states in its concluding remarks:
Comparison of the present extent of planetary change with that characterizing past global-scale state shifts, and the enormous global forcings we continue to exert, suggests that another global-scale state shift is highly plausible within decades to centuries, if it has not already been initiated.
What might these mean for how we choose to respond to the threat that industrial capitalism – and indeed, the activities we of the First World take for granted – pose to the smooth functioning of Earth’s ecosystems, and the lives of billions of our fellow humans? It increasingly goes without saying that the current trends in sustainable development and environmentally-friendly practices are essentially negligible when compared to the continued hegemony of business-as-usual. Does this mean that those who are really serious about protecting nature and human lives must embark on a far more radical path than that which is typically praised in contemporary society? Only time will tell. And unfortunately, we seem to be running out of just that.