Earth System Analysis, Potsdam Institute for Climate Impact Research, Member of the Leibniz Association, 14473 Potsdam, Germany;
Complexity Science, Potsdam Institute for Climate Impact Research, Member of the Leibniz Association, 14473 Potsdam, Germany.
Proc Natl Acad Sci U S A. 2020 Jun 9;117(23):12915-12922. doi: 10.1073/pnas.1916545117. Epub 2020 May 20.
We will need collective action to avoid catastrophic climate change, and this will require valuing the long term as well as the short term. Shortsightedness and uncertainty have hindered progress in resolving this collective action problem and have been recognized as important barriers to cooperation among humans. Here, we propose a coupled social-ecological dilemma to investigate the interdependence of three well-identified components of this cooperation problem: 1) timescales of collapse and recovery in relation to time preferences regarding future outcomes, 2) the magnitude of the impact of collapse, and 3) the number of actors in the collective. We find that, under a sufficiently severe and time-distant collapse, how much the actors care for the future can transform the game from a tragedy of the commons into one of coordination, and even into a comedy of the commons in which cooperation dominates. Conversely, we also find conditions under which even strong concern for the future still does not transform the problem from tragedy to comedy. For a large number of participating actors, we find that the critical collapse impact, at which these game regime changes happen, converges to a fixed value of collapse impact per actor that is independent of the enhancement factor of the public good, which is usually regarded as the driver of the dilemma. Our results not only call for experimental testing but also help explain why polarization in beliefs about human-caused climate change can threaten global cooperation agreements.
我们需要采取集体行动来避免灾难性的气候变化,而这需要重视长期和短期利益。短视和不确定性阻碍了解决这一集体行动问题的进展,被认为是人类合作的重要障碍。在这里,我们提出了一个耦合的社会生态困境来研究合作问题的三个明确组成部分的相互依存关系:1)与未来结果的时间偏好相关的崩溃和恢复的时间尺度,2)崩溃的影响程度,3)集体中的参与者数量。我们发现,在足够严重和时间遥远的崩溃下,参与者对未来的关注程度可以将博弈从公地悲剧转变为协调博弈,甚至变为合作占主导地位的公地喜剧。相反,我们也发现了即使是强烈关注未来也不能将问题从悲剧转变为喜剧的条件。对于大量参与的参与者,我们发现,这些博弈规则变化发生的关键崩溃影响收敛到每个参与者的崩溃影响的固定值,该值独立于公共利益的增强因子,而公共利益通常被认为是困境的驱动因素。我们的研究结果不仅呼吁进行实验测试,还帮助解释了为什么对人类引起的气候变化的信念的两极化会威胁到全球合作协议。