January 24 2013, 7.24pm
Our impact on the earth has brought on a new geographical epoch – The Age of Humans.AAP/Damien Shaw
In response to the heatwave that set a new Australia-wide
January 24 2013, 7.24pm
Our impact on the earth has brought on a new geographical epoch – The Age of Humans.AAP/Damien Shaw
In response to the heatwave that set a new Australia-wide record on 7 January, when the national average maximum reached 40.33°C, the Bureau of Meteorology issued a statement that, on reflection, sounds the death knell for all of the social sciences taught in our universities.
“Everything that happens in the climate system now”, the manager of climate monitoring at the Bureau said, “is taking place on a planet which is a degree hotter than it used to be.”
Eminent US climate scientist, Kevin Trenberth, made the same point more fully last year:
The answer to the oft-asked question of whether an event is caused by climate change is that it is the wrong question. All weather events are affected by climate change because the environment in which they occur is warmer and moister than it used to be.
Trenberth’s commentary calls on us to reframe how we think about human-induced climate change. We can no longer place some events into the box marked “Nature” and some into the box marked “Human”.
The invention of these two boxes was the defining feature of modernity, an idea founded on Cartesian and Kantianphilosophies of the subject. Its emergence has also been tracked by science studies in the contradiction between purified science and the messy process of knowledge creation, leading to Bruno Latour’s troubling claim that the separation of Human and Nature was an illusion, and that “we have never been modern”.
Climate science is now telling us that such a separation can no longer be sustained, that the natural and the human are mixed up, and their influences cannot be neatly distinguished.
This human-nature hybrid is true not just of the climate system, but of the planet as a whole, although it would be enough for it to be true of the climate system. We know from the new discipline of Earth system science that changes in the atmosphere affect not just the weather but the Earth’s hydrosphere (the watery parts), the biosphere (living creatures) and even the lithosphere (the Earth’s crust). They are all linked by the great natural cycles and processes that make the planet so dynamic. In short, everything is in play.
Apart from climatic change, it is apparent that human activity has transformed the Earth in profound ways. Every cubic metre of air and water, every hectare of land now has a human imprint, from hormones in the seas, to fluorocarbons in the atmosphere and radioactivity from nuclear weapons tests in the soil.
Each year humans shift ten times more rock and soil around the Earth than the great natural processes of erosion and weathering. Half of the land surface has been modified by humans. Dam-building since the 1930s has held back enough water to keep the oceans three centimetres lower than otherwise. Extinctions are now occurring at a rate 100 times faster than the natural one.
So profound has been the influence of humans that Earth scientists such as Will Steffen have recently declared that the Earth has entered a new geological epoch, an epoch defined by the fact that the “human imprint on the global environment has now become so large and active that it rivals some of the great forces of Nature in its impact on the functioning of the Earth system”. Known as the Anthropocene, the Age of Humans, it marks the end of the Holocene, the 10,000-year period of remarkable climatic stability and clemency that allowed civilisation to flourish.
The modern social sciences — sociology, psychology, political science, economics, history and, we may add, philosophy — rest on the assumption that the grand and the humdrum events of human life take place against a backdrop of an inert nature. Only humans have agency. Everything worthy of analysis occurs in the sealed world of “the social”, and where nature does make itself felt – in environmental history, sociology or politics – “the environment” is the Umwelt, the natural world “over there” that surrounds us and sometimes intrudes on our plans, but always remains separate.
What was distinctive of the “social