Lucy Carpenter on how our oceans are destroying ozone

In this episode of The Life Scientific, host Jim Al-Khalili interviews Professor Lucy Carpenter, an experimental atmospheric chemist from the University of York, about her groundbreaking work revealing that the ocean actively shapes atmospheric chemistry—challenging the long-held view that only human activity affects ozone. Carpenter discusses her pioneering research at the Cape Verde Atmospheric Observatory, established in 2006 on the remote island of São Vicente, where she discovered that marine halogens—released by seaweed and ocean biology—drive significant ozone destruction in the tropical Atlantic, accounting for up to 15% of global ozone loss. This discovery, published in Nature in 2008, reshaped climate models by introducing marine halogen chemistry as a critical factor. Carpenter also reflects on her journey from a childhood fascination with chemistry demonstrations to becoming co-chair of the scientific assessment panel for the Montreal Protocol, the global treaty protecting the ozone layer. She highlights both the successes of the Protocol and ongoing challenges, particularly with potent greenhouse gases like HFC-23, which are increasing despite international efforts. Beyond science, Carpenter shares her passion for duathlons, drawing parallels between athletic endurance and the long-term resilience required in scientific research. Her message to young scientists is one of hope: short-lived pollutants can be reversed quickly, and curiosity-driven, collaborative science can drive meaningful global change. Key takeaways include: 1) The ocean is not just affected by the atmosphere—it actively alters it through halogen emissions; 2) Marine chemistry, especially from seaweed, plays a major role in ozone destruction and cloud formation; 3) The Montreal Protocol is a success story, but new challenges like HFC-23 require urgent global action; 4) Short-lived pollutants can be cleaned up rapidly if emissions stop, as seen during the COVID-19 lockdowns; 5) Scientific progress thrives on curiosity, collaboration, and persistence; 6) Personal resilience—whether through sport or passion—can sustain long-term scientific careers; 7) Climate solutions exist, and they are within reach if political will follows scientific evidence; 8) Long-term atmospheric monitoring sites like Cape Verde are vital for understanding global change.