As the effects of climate change are increasingly being felt around the world, the need to transition away from fossil fuels is becoming more urgent. An electrified world requires more batteries, which in turn means the demand for metals, such as nickel, is rising. Mining those metals can often have devastating consequences for ecosystems, destroying and polluting vast landscapes. But there is another way to get these metals—from the floor of the Pacific Ocean. an area over 4km below the ocean’s surface offers an alternative. The companies proposing to harvest these metals argue that mining the deep sea would be less environmentally damaging than land-based mining. But many ecologists disagree.  The Economist’s Hal Hodson explores the diversity of deep-sea ecology by visiting Adrain Glover’s lab at the Natural History Museum in London. Gerard Barron, the boss of The Metals Company, outlines the case for mining the ocean floor. Lisa Levin of Scripps Institution of Oceanography and Anna Metaxas, an oceanographer at Dalhousie University, share their concerns over the lack of evidence of the impact of deep-sea mining. Plus, Sue-Lin Wong, The Economist’s South East Asia correspondent, reports on the destruction that traditional land-based mining in Indonesia causes to the country’s rainforests. Alok Jha, The Economist’s science and technology editor, hosts. For full access to The Economist’s print, digital and audio editions subscribe at economist.com/podcastoffer and sign up for our weekly science newsletter at economist.com/simplyscience. Hosted on Acast. See acast.com/privacy for more information.