The complexity of climate change mitigation: an experiment with large groups

Abstract

We have studied the problem of climate change mitigation in large groups by means of a series of experiments with 1785 people. Our participants included both young university students and people of relevance in different organizations, in particular, those attending the presentation of the annual report on innovation by Fundación COTEC (Spain). In the experiment, the participants, distributed in groups of more than 100 people, faced a dilemma: to avoid a global catastrophe that destroys any possibility of making profits, a certain collective sacrifice has to be made by contributing to reach a global threshold. When the threshold was low, the students reached the amount of overall contribution necessary to avoid it. But in the case of a high threshold, none of the populations reached the threshold. In fact, they were far from it. In this sense, the collective behavior of the students and of people of relevance was fundamentally the same. The majority of participants in the high-risk case fell into four categories: those who did not contribute (around 10%), those who contribute half of their means (15%) but less than the fair share required to reach the threshold, those who contributed the fair share (10%), and those who contributed everything they had, so that their personal benefit was zero. In the case of students this last percentage was 10%, but in the other sample it reached almost 30%. We also found that individuals could be classified as being optimistic or pessimistic, and in general they behaved accordingly with regard to their contributions. Our results highlight the complexity of mitigating climate change in large groups and specially the difficulty in communicating the issue to foster action in a general population.