Could civilization collapse? NASA-funded study looks at framework for how, when

A new study partially funded by NASA suggests heavy demands on the world's natural resources and extreme economic imbalances could spell a premature end for modern human civilization.

The research paper, titled "Human and nature dynamics (HANDY): modelling inequality and use of resources in the collapse or sustainability of societies," was published this month in the journal Ecological Economics.

Led by Dr. Safa Motesharrei, a mathematician at the University of Maryland, the study's authors applied human factors such as wealth, economic disparities and use of natural resources to a scientific model typically used to study the interaction of animal populations.

With this model, the researchers say they are able to estimate a human society's "carrying capacity," which is a method, they say, for determining its overall destruction.

UMD professor and study co-author Eugenia Kalnay says the model shows that sustained exploitation of natural resources can eventually lead to a catastrophic societal breakdown.

"And if inequality continues such that the rich consume far more than the poor, the system eventually collapses," Kalnay said.

However, the authors emphasize that HANDY is "not a forecasting model," and is not intended to explain any specific societies' collapse, "but rather to provide a general framework that allows carrying out 'thought experiments' for the phenomenon of collapse and to test changes that would avoid it."

Says Motesharrei: "It cannot be used to predict the future of any society. It can, however, help us understand the possible underlying mechanisms in the evolution of society."

Putting a positive spin on the study's results, the authors says that human societies are able to reach a sustainable state when they avoid economic inequality and limit resource use.

"We can, as humans, make critical choices that can change the long-term path that our social system will take, and we can optimize such choices using scientific models," said study co-author Jorge Rivas, of the Institute of Global Environment and Society.

The study was sponsored by NASA's Goddard Space Flight Center.