The threat of thermonuclear war weapons feels closer now than any time since the Cold War. The devastating consequences for land-based ecosystems are well-understood. But how would the ocean, a haven for life in previous mass-extinction events, fair after a nuclear engagement? For Halloween, Dr Tyler Rohr from the Institute for Marine and Antarctic Studies will be delving into the chilling prospects of massive global cooling following a large nuclear conflict, and how it could endanger ocean life as we know it.