The paper in Nature Sustainability is available here: http://go.nature.com/2D4FHNj
Many life situations can be characterized as a social dilemma: we have to balance what is in our own interests against the interests of others and society at-large. If everyone helps sustain life on earth, we'd all be better off, but if no one does, we're all significantly worse off. Unfortunately, the dilemma is that at the individual level, the incentive is often to act in our own self-interest.
Given this dilemma, economists frequently struggle to explain why people help others, especially when helping comes at a significant personal cost. James Andreoni first used the term "warm-glow" to denote the fuzzy warm feeling people experience when they give to charity or help others in need. In fact, he suggested that the warm-glow of doing good stands in contrast to the cold-prickle of doing something bad!
Much has been written about when and why people behave altruistically. For example, most of us experience empathy when we recognize sadness and suffering in others. But what about more abstract issues such as concern for the planet itself? Or future generations of strangers who haven't been born yet? Why would we incur a personal cost now, to help save a stranger from future global warming? These are the intriguing but difficult questions I am interested in.
There is some reason to be optimistic: recent research shows that people often feel good after helping the environment. Yet, this fact does not tell us whether people help the environment because they anticipate that it will make them feel good, especially when doing so may be difficult and costly.
To investigate this, I asked a nationally representative cohort of adults how positive or negative they would feel about helping to reduce climate change. Four weeks later, I followed up with the same individuals and asked them to report on a wide range of green behaviors, from buying local produce and switching off lights to buying green energy and insulating one's home. What I found was that the anticipated warm-glow from helping to save the planet does in fact predict green behavior four weeks later! This was true for both liberals and conservatives. However, a closer examination revealed that this correlation was much stronger for low-cost, easier actions, and much weaker for more effortful, high-cost behavior changes. For example, recycling may help people feel good about being sustainable, but practically, it's not the most impactful behavior (e.g. compared to buying green energy).
Nonetheless, the finding that people derive and anticipate internal pleasure from helping to save the planet is important for public policy. If people act green because they desire a warm-glow from engaging in a virtuous moral behavior, extrinsic economic incentives, such as financial rewards, could dilute the purity of the prosocial act and in fact, be counterproductive at times. Not to mention the fact that extrinsic incentives are costly and difficult to maintain. If people derive positive emotions from acting sustainably, they are arguably more likely to continue that behaviour on their own because it is internally rewarding.
In my study, I did not experimentally evaluate whether intrinsic motivation to help the planet actually sustains behaviour change longer than extrinsic policy incentives, but I would strongly invite future experimental work to tackle this important question.
"Warm glow is associated with low- but not high-cost sustainable behaviour"
Sander van der Linden (2018) is published in Nature Sustainability 1, 28-30. DOI:10.1038/s41893-017-0001-0