Civilisation could collapse within decades because of unsustainable resources exploration and unequal wealth distribution, a NASA study claims.
The Guardian reports that scientists, sponsored by Nasa's Goddard Space Flight Centre, developed a model of how a "perfect storm" of crises could unravel global civilisation.
The study looked at the dynamics of human-nature at the time of past cases of collapse, identifying population, climate, water, agricultural and energy factors which may help determine the risk of collapse.
According to The Guardian, the research was based on a new cross-disciplinary Human and Nature DYnamical (HANDY) model, led by applied mathematician Safa Motesharri of the US National Science Foundation-supported National Socio-Environmental Synthesis Centre, in association with a team of natural and social scientists. The study based on the HANDY model has been accepted for publication in the peer-reviewed Elsevier journal, Ecological Economics.
The study found that according to historical records, even advanced, complex civilisations were susceptible to collapse, raising questions about the sustainability of modern civilisation.
"The fall of the Roman Empire, and the equally (if not more) advanced Han, Mauryan, and Gupta Empires, as well as so many advanced Mesopotamian Empires, are all testimony to the fact that advanced, sophisticated, complex, and creative civilizations can be both fragile and impermanent," Dr Motesharri said. "These factors can lead to collapse when they converge to generate two crucial social features."
Currently, high levels of economic stratification are linked directly to overconsumption of resources, The Guardian reports.
The study reportedly challenges those who argue that technology will resolve these challenges by increasing efficiency.
Technological change can raise the efficiency of resource use, but it also tends to raise both per capita resource consumption and the scale of resource extraction, so that, absent policy effects, the increases in consumption often compensate for the increased efficiency of resource use, researchers claim.
Productivity increases in agriculture and industry over the last two centuries has come from "increased (rather than decreased) resource throughput" despite dramatic efficiency gains over the same period.
Modelling a range of different scenarios, Dr Motesharri and his colleagues concluded that under conditions "closely reflecting the reality of the world today... we find that collapse is difficult to avoid".
According to The Guardian article, the first scenario shows overconsumption resulting in a famine among "commoners" that eventually causes the collapse of society. "It is important to note that this Type-L collapse is due to an inequality-induced famine that causes a loss of workers, rather than a collapse of Nature," researchers say.
Another scenario focuses on the role of continued resource exploitation, finding that "with a larger depletion rate, the decline of the Commoners occurs faster, while the elites are still thriving, but eventually the Commoners collapse completely, followed by the elites."
"While some members of society might raise the alarm that the system is moving towards an impending collapse and therefore advocate structural changes to society in order to avoid it, Elites and their supporters, who opposed making these changes, could point to the long sustainable trajectory 'so far' in support of doing nothing," the study reveals.
However scientists told The Guardian that the worst-case scenarios weren't inevitable and suggested that appropriate policy and structural changes could avoid collapse.
The two key solutions are to reduce economic inequality so as to ensure fairer distribution of resources, and to dramatically reduce resource consumption by relying on less intensive renewable resources and reducing population growth, they said.