Curbing Climate Change

Scientists widely agree that humans are the dominant cause of rising global temperatures. Now, a new study shows that people’s perceived risk from extreme events associated with climate change can influence them to alter behaviors in ways that reduce greenhouse gas emissions.

Conducted by a joint synthesis team of researchers on human risk perception and climate change from the National Socio-Environmental Synthesis Center (SESYNC) at the University of Maryland and the National Institute for Mathematical and Biological Synthesis (NIMBioS) at the University of Tennessee, the study used a new joint model that couples a widely used climate change prediction model, known as C-ROADS, with a social model of human behavioral change.

“Our model results suggest that simultaneously addressing a set of human social processes is key to understanding mitigation behaviors and curbing future climate change,” the multi-disciplinary, multi-institution team of researchers wrote in a study published on January 2 in the journal Nature Climate Change.

By combining climate projections and social processes, their new model predicts a global temperature change ranging from 3.4 to 6.2 degrees Celsius (6.12 to 11.2 degrees Fahrenheit) by the year 2100, compared to the 4.9 degrees Celsius change predicted by the climate model alone.

Due to the complexity of the physical processes that determine climate, climate models have uncertainties in global temperature prediction. And the new model found that temperature uncertainty associated with the social component was of a similar magnitude to that of the physical processes. This implies that a better understanding of the human social component is important but often overlooked in modeling climate change.

“SESYNC was excited to support this project because our core mission is to promote interactions between social and environmental sciences just like those in this research team. Environmental problems are inherently linked to social dynamics and this work shows that recognizing and studying these linkages in interdisciplinary teams can reveal potential pathways to solutions that will benefit both people and ecological systems,” said Margaret Palmer, director of SESYNC and Distinguished University Professor at the University of Maryland.

Based in Annapolis, SESYNC brings together researchers studying the science of the natural world with those studying the science of human behavior and decision making to find solutions to complex environmental problem.

The new study found that long-term, less easily reversed behavioral changes, such as insulating homes or purchasing hybrid cars, had by far the most impact in mitigating greenhouse gas emissions and reducing climate change, versus more short-term modifications, such as adjusting thermostats or driving fewer miles.

“A better understanding of the human perception of risk from climate change and the behavioral responses are key to curbing future climate change,” said lead author Brian Beckage, a professor of plant biology and computer science at the University of Vermont.

NIMBioS Director Louis J. Gross, who co-authored the paper and co-organized the working group said: “It is easy to lose confidence in the capacity for societies to make sufficient changes to reduce future temperatures. When we started this project, we simply wanted to address the question as to whether there was any rational basis for ‘hope’—that is a rational basis to expect that human behavioral changes can sufficiently impact climate to significantly reduce future global temperatures.

“Climate models can easily make assumptions about reductions in future greenhouse gas emissions and project the implications, but they do this with no rational basis for human responses,” Gross said. “The key result from this paper is that there is indeed some rational basis for hope.”

That basis for hope can be the foundation which communities can build on in adopting policies to reduce emissions, said co-author Katherine Lacasse, an assistant professor of psychology at Rhode Island College.

“We may notice more hurricanes and heat waves than usual and become concerned about climate change, but we don’t always know the best ways to reduce our emissions,” Lacasse said. “Programs or policies that help reduce the cost and difficulty of making long-term changes or that bring in whole communities to make long-term changes together can help support people to take big steps that have a meaningful impact on the climate.”

The National Socio-Environmental Synthesis Center (SESYNC) at the University of Maryland and the National Institute for Mathematical and Biological Synthesis (NIMBioS) at the University of Tennessee are both supported by the National Science Foundation.