Background: It is now essential for students to learn in the science classroom about climate change and the part they can play in ameliorating its consequences. This requires science teachers to have a secure understanding of climate change. Purpose: The aim of this study is to investigate the effectiveness of a two-day outdoor educational workshop on preservice teachers' awareness of climate change and the role of forests in mitigating the effects of climate change. Participants: 20 pre-service teachers voluntarily participated in the workshop. Design and method: A one-group pre-and post-test design was used to investigate the changes in preservice teachers' cognitive structures after attending the workshop. Data were collected using a word association test (pre and post) and participants' reflection forms (post). The cut-off technique was used in analysing the word association test and thematic analysis was used in analysing participants' reflection forms. Results: The results indicated that the workshop stimulated preservice teachers' cognitive structures and conceptual understandings of climate change. Moreover, they generally had positive opinions about the workshop activities, emphasizing that these increased their awareness and empathy skills. However, they also indicated a small range of negative factors including a lack of time, materials, and opportunity to debate, and being tired. Conclusions: Non-formal outdoor learning programmes can promote learning and increase preservice teachers' awareness with respect to climate change.