In the coming century, average temperatures are predicted to increase by 2.5 to ten degrees Fahrenheit as a result of climate change. Yet citizens around the world vary in their perceptions of how serious the threat of rising temperatures is. I argue that variation in the perceived seriousness of climate change reflects the degree to which individuals internalize the welfare of others in society besides themselves. I describe and two models of “other-regarding” preferences - social welfare maximization and inequity aversion - and test their predictions using data from the World Values Survey. I employ genetic matching and a difference-in-difference design in order to mitigate potential endogeneity. I also explore behavioral implications of the theory using original data on climate change-related web searches. The empirical tests support the argument: individuals who exhibit high levels of other-regarding preferences are more likely to express serious concern - and seek out new information - about global warming.