1. Summary
Since 2004, podcasts have emerged as a decentralised medium for science communication to the global public. However, to-date, there have been no large-scale quantitative studies of the production and dissemination of science podcasts. This study identified 952 English language science podcasts available between January and February 2018 and analysed online textual and visual data related to the podcasts to classify key production parameters. The total number of science podcast series available grew linearly between 2004 and 2010, and then exponentially between 2010 and 2018. 65% of science podcast series were hosted by scientists and 77% were targeted to public audiences. Although a wide range of primarily single-subject science podcasts series were noted, 34% of science podcast series were not dedicated to single subject. Compared to biology and physics, chemistry may be under-represented by science podcasts. Only 24% of science podcast series had any overt financial income. 62% of science podcast series were affiliated to an organisation; producing a greater number of episodes (median = 24, average = 96) than independent podcast series (median = 24, average = 96). This study provides a fundamentally new ‘snapshot’ of how science podcasts are being used to communicate science with global public audiences.