(Phys.org)—A pair of researchers with the University of Cologne in Germany has found that phrasing pro-environmental messages in past-focused ways was received more warmly by people who described themselves as conservatives than messages that warned of future problems. In their paper published in Proceedings of the National Academy of Sciences, Matthew Baldwin and Joris Lammers describe the study they carried out with online volunteers and why they believe their results could have a real-world impact.