Human activity, predominantly the global economic system, is now the prime driver of change in the Earth System - the sum of our planet's interacting physical, chemical, biological and human processes. This is the conclusion made visible in a set of 24 global indicators, or a "planetary dashboard", published in the latest issue of Anthropocene Review, 16 January 2015.
The research charts the "Great Acceleration" in human activity from the start of the industrial revolution in 1750 to 2010, and the subsequent changes in the Earth System – e.g. greenhouse gas levels, ocean acidification, deforestation and biodiversity deterioration.
The original 24 indicators were published in the first synthesis of the International Geosphere-Biosphere Programme (IGBP) in 2004, when Professor Will Steffen was their Executive Director. Today he is a researcher at the Australian National University and the Stockholm Resilience Centre.
"It is difficult to overestimate the scale and speed of change. In a single lifetime humanity has become a geological force at the planetary-scale," says Will Steffen, who is lead author of the new study, which is the result of a joint project between the Centre and IGBP.
Indicators of people and planet
Twelve indicators depict human activity, for example economic growth (GDP); population; foreign direct investment; energy consumption; telecommunications; transportation and water use.
Another twelve indicators show changes in major environmental components of the Earth System, for example the carbon cycle; the nitrogen cycle and biodiversity. This new "planetary dashboard" highlights how the trajectories of Earth and human development are now tightly bound.
"When we first aggregated these datasets, we expected to see major changes but what surprised us was the timing. Almost all graphs show the same pattern. The most dramatic shifts have occurred since 1950. We can say that around 1950 was the start of the Great Acceleration," says Steffen.
"After 1950 we can see that major Earth System changes became directly linked to changes largely related to the global economic system. This is a new phenomenon and indicates that humanity has a new responsibility at a global level for the planet"
Will Steffen, lead author
One success story
"Of all the socio-economic trends only construction of new large dams seems to show any sign of the bending of the curves – or a slowing of the Great Acceleration," says co-author Lisa Deutsch, Senior Lecturer at the Centre.
"Only one Earth System trend indicates a curve that may be the result of intentional human intervention – the success story of ozone depletion. The levelling off of marine fisheries capture since the 1980s is unfortunately not due to marine stewardship, but to overfishing," she continues.
The findings provide strong evidence that in recent decades key components of the Earth System have moved beyond the natural variability exhibited in the last 12,000 years, a period geologists call the Holocene. The Holocene, Latin for "entirely recent", began at the end of the last ice age and provided the stability for agriculture to develop, leading eventually to townships and cities to flourish.
The Great Acceleration trends support the proposal that Earth has entered a new geological epoch, the Anthropocene.
The new paper argues that: "Of all the candidates for a start date for the Anthropocene, the beginning of the Great Acceleration is by far the most convincing from an Earth System science perspective. It is only beyond the mid-20th century that there is clear evidence for fundamental shifts in the state and functioning of the Earth System that are beyond the range of variability of the Holocene, and driven by human activities and not by natural variability."
The new study also concludes that the bulk of economic activity, and so too, for now, the lion's share of consumption, remain largely within the OECD countries, which in 2010 accounted for about 74% of global GDP but only 18% of the global population. This points to the profound scale of global inequality, which distorts the distribution of the benefits of the Great Acceleration and confounds international efforts, for example climate agreements, to deal with its impacts on the Earth System.
However, the paper shows that recently, global production, traditionally based within OECD countries, has shifted towards BRICS nations – Brazil, Russia, India, China and South Africa. Moreover, the mushrooming middle classes in BRICS nations are driving greater consumption here too.
About one half of the global population now lives in urban areas and about third of the global population has completed the transition from agrarian to industrial societies. This shift is evident in several indicators. Most of the post-2000 rise in fertilizer consumption, paper production and motor vehicles has occurred in the non-OECD world.