Prof. Hans-Otto Poertner is a physiologist and marine biologist at the Alfred Wegener Institute Helmholtz Centre. He explores the impact of climate change on ecosystems and physiology, with a focus on polar and marine regions. He is currently Co-Chair of the IPCC's Working Group II and was previously Coordinating Lead Author of Oceans Systems Chapter. Hans-Otto joins to discuss the relation between humans and ecosystems, the climate change implementation gap, and the need to rapidly transform society away from fossil fuels.