Training a scientific workforce in order to mitigate the impacts of climate change drives an international need for climate science education, including in Ghana. How preservice teachers understand climate change, and the often misunderstood relationship between ozone depletion and global warming, critically impacts the students they will teach. This mixed method, descriptive study explores preservice teachers' climate change and ozone depletion knowledge, and documents the sources of their ideas. Elementary preservice science teachers from three colleges of education in Ghana completed a survey (N = 255) and interview (n = 30). Exploratory factor analysis yielded six factors related to ozone depletion and four related to climate change knowledge. Survey and interview responses revealed that the preservice teachers could explain that stratospheric ozone is a layer of gas in the atmosphere that prevents ultraviolet radiation from reaching Earth. Yet, they could not describe how ozone forms and the mechanism of ozone destruction. The preservice teachers confused climate change with changes in weather and seasons, but could explain how anthropogenic activities like deforestation and burning fossil fuels contribute to climate change. About 88% of the participants thought climate change and ozone depletion were causally linked -- either ozone depletion caused climate change, or climate change caused ozone depletion. The participating preservice teachers identified textbooks (80%), instructors (64%), and the media (62%) as the main sources of their ozone depletion and climate change knowledge. We identified a mix of knowledge gaps and coherent ideas that offer scaffolds on which to improve teachers' knowledge of climate change and ozone depletion.