Ballooning 10 billion world population drives moderate-to-high worries, study finds

Providing rare empirical evidence on the increasingly vital question of how the public perceives global population growth (GPG) risks, the study comes at a time when scholars are finding that individuals' risk perceptions can motivate precautionary behaviors, including their willingness to support government measures to reduce related risks.

"When the global human population reached seven billion in late 2011, it attracted a lot of media attention and generated a wealth of related discourse among academics," says Associate Professor Ian Dawson of the University of Southampton Business School, Centre for Risk Research, United Kingdom, who together with colleague Professor Johnnie Johnson conducted the new study. Although much discussion was held about GPG's potentially adverse effects, "I wasn't aware of any studies that had attempted to assess the extent to which the public shared these concerns," Dawson adds. With a grant from University of Southampton's Annual Adventures in Research fund, in 2014 the authors undertook a study of public risk perceptions regarding GPG.

In their study, "Does Size Matter? A Study of Risk Perceptions of Global Population Growth," the authors present findings from a telephone survey of 300 residents of England, Northern Ireland, Scotland, and Wales ages 18 and older. Their 47-question survey was designed to collect information about public perceptions and knowledge of GPG, the willingness of individuals to adopt mitigation/precautionary behaviors, and the underlying reasons for variations in these factors. The study was published in the online version of Risk Analysis, a publication of the Society for Risk Analysis.

A key finding was that "the individuals who perceived greater levels of risk from population growth were generally those who indicated a greater willingness to embrace mitigation behaviors and support preventative actions," says Dawson. The findings "are particularly important as they suggest that greater concern about the potential adverse effects of global population growth might act as an important catalyst for behavioral changes that could help humanity better manage some of the related challenges, such as conserving valuable resources and mitigating human-induced climate change."

The foremost concerns of respondents who perceive medium-to-high risks were the greater likelihood of ecological damage, resource shortages, and violent conflict, the study found. In addition, the worst effects from a more crowded world are likely to occur in the mid-21st century, respondents felt, and most likely to be experienced by the world's poorest people. Approximately half of respondents (50.3%) believed that governments rather than individuals or communities had the greatest ability to influence global population levels, and most agreed national governments were not doing enough to tackle GPG.

"Discussions about global population growth are often absent from modern political discourse," perhaps because there are social taboos, scientific uncertainties, it is a polarizing topic, or other reasons, Dawson notes. "In democratically representative politics, this is at odds with the finding that public concern about global population growth is relatively high. Hence, it could be argued that there is a need for policymakers to take greater steps towards openly discussing global population growth and to make greater efforts to gauge and respond to the public's related concerns," he adds. In Dawson's view, such open discussions could play an important part in helping people to develop a better understanding of GPG and its potential effects and, in response, "to work collectively towards proportionate responses that enable humanity to capitalize on any associated benefits while carefully managing any related risks." The study found that individuals lacked a good understanding of GPG statistics, such as the projected size of the population across the 21st Century.

Among those surveyed, older respondents with relatively low risk perceptions were the least willing to change their behavior. "While the present study found that many younger people perceived the risk of global population growth as relatively high," Dawson says, "it could be seen as reassuring that the study found that these younger people, who stand to inherit and occupy a more populated world, are those that tended to be most willing to adopt mitigation actions."