The Earth System, the Anthropocene and global tipping points

“Treating ‘humans’ as a single, monolithic whole, ignores the fact that the Great Acceleration has, until very recently, been almost entirely been driven by a small fraction of the human population, those in developed countries.”

“The most striking insight is that most of the population growth has been in the non-OECD world but the world’s economy (GDP) is still strongly dominated by the OECD world. Despite the shift of global production, traditionally based within OECD countries, towards the BRICS nations, the bulk of economic activity, and with it, the lion’s share of consumption, remain largely within the OECD countries.

In 2010 the OECD countries accounted for 74% of global GDP but only 18% of the global population. Insofar as the imprint on the Earth System scales with consumption, most of the human imprint on the Earth System is coming from the OECD world.

This points to the profound scale of global inequality, which distorts the distribution of the benefits of the Great Acceleration and confounds efforts to deal with its impacts on the Earth System.”

“In addition, the effects of the Great Acceleration on the functioning of the Earth System are cumulative over time, most clearly evident in the climate system, and the historic inequalities embedded in the origin and trajectory of the Great Acceleration continue to plague negotiations to deal with its consequences.”

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In this excellent talk, Professor Steffen talks about the science of measuring humanity’s effect on the planet. Using tangible, real measures, he shows us the profound change in the planet since the Industrial Revolution and argues that now, more than at any other time, humanity is the single most influential factor in global changes; so much so that we should recognise that now is the age of mankind – The Anthropocene.

Human pressures on the planet as a whole – the ‘Earth System’ – have now become so great that scientists have proposed that we have left the Holocene, the 11,700-year geologic epoch that has been humanity’s accommodating home, and have entered a new geologic epoch, the Anthropocene, characterised by extremely rapid changes to the climate system driven primarily by human emissions of greenhouse gases and growing degradation of the planet’s biosphere, driven by a range of direct and indirect human pressures.

Where is the Anthropocene headed? The current trajectory of the Earth System is a rapid exit from the Holocene, accelerating towards a much hotter climate system and a degraded, ill-functioning biosphere. Perhaps most concerning is a possible ‘fork in the road’ beyond which lies ‘Hothouse Earth’.

The key element of this trajectory is a ‘tipping cascade’, in which a series of interlinked tipping points – the melting of polar ice, the conversion of forest biomes to grasslands or savannas, changes in ocean and atmospheric circulation – take control of the trajectory of the Earth System and move it to a much hotter, biodiversity-impoverished, but stable state. Professor Will Steffen (Climate Council of Australia, Australian National University) argues that avoiding this possible tipping cascade requires fundamental changes to human societies. These changes include not only advances in technologies but also more fundamental changes in societal structures and core values.

Click below to view video:

Read scientific paper: Will Steffen, et al, The Trajectory of the Anthropocene: The Great Acceleration, The Anthropocene Review, March 2015

https://www.researchgate.net/publication/272418379_The_Trajectory_of_the_Anthropocene_The_Great_Acceleration