In the debate on climate change commentators often express pessimistic or optimistic views. We see this mainly in the media and popular literature, but also in various academic fields. The aim of this paper is to investigate different kinds of pessimistic and optimistic views put forward in this debate and suggest explanations of the diversity of views. The paper concludes that pessimism and optimism may concern, for example, climate change as an unmitigated or poorly mitigated process, mitigation of climate change or specific measures of mitigation. These aspects are important to distinguish, because a person can be pessimist concerning climate change as an unmitigated or poorly mitigated process and optimist concerning mitigation of climate change, and be pessimist concerning one specific mitigation measure and optimist concerning another. It is suggested that the diversity of pessimistic and optimistic views is due to the uncertainty of scientific climate models and the influence of evaluative and ideological assumptions.

在关于气候变化的辩论中，评论员经常表达悲观或乐观的观点。我们主要在媒体和通俗文学中看到这一点，但在各个学术领域也看到了这一点。本文的目的是调查在这场辩论中提出的不同类型的悲观和乐观观点，并就观点的多样性提出解释。该论文的结论是，悲观主义和乐观主义可能涉及，例如，气候变化作为一个未缓解或缓解不佳的过程、气候变化的缓解或具体的缓解措施。区分这些方面很重要，因为一个人可能对气候变化作为一个未缓解或缓解不佳的过程持悲观态度，对气候变化的缓解持乐观态度，对一项具体的缓解措施持悲观态度，对另一项具体缓解措施持乐观态度。