The Conversation Weekly

Nadir Jeevanjee, a physical scientist at NOAA's Geophysical Fluid Dynamics Laboratory, shares insights on the history of climate models. He highlights Syukuro Manabe's groundbreaking work and his 1967 predictions about CO2-induced warming. Jeevanjee explains how early models accurately forecasted phenomena like polar amplification and stratospheric cooling. He also discusses the alarming threats to climate data collection due to recent funding cuts, emphasizing the importance of these foundational models in today's climate science and discussions.

Robert Muggah, founder of the Igarapé Institute and a researcher at Princeton's Brazil LAB, dives into the deep-rooted issue of organized crime in Brazil. He explains how groups like the Commando Vermelho have expanded from prisons into various sectors like mining and fintech. Muggah discusses the recent violent police raid in Rio, its political implications, and the public's mixed reactions. He also suggests that heavy-handed tactics often exacerbate the problem and emphasizes the need for community-focused policing and financial strategies to combat crime effectively.

Penelope Geng, an associate professor of English at Macalester College, dives into 16th-century fears surrounding witches and demons. She recounts James VI's terrifying royal journey and his witchcraft fears, prompting him to write ‘Daemonologie.’ Explore the clash between Protestantism and ghostly beliefs, and how this shaped societal views on supernatural entities. Geng also discusses the lingering impact of these beliefs in modern culture, contrasting the fear of demons with the nostalgia for ghosts.

Larisa Yarovaya, Director of the Centre for Digital Finance at the University of Southampton, dives into the world of corporate cryptocurrency. She discusses how MicroStrategy's bold Bitcoin purchases sparked a trend among public companies, holding over $114 billion in Bitcoin. Yarovaya highlights the risks of volatility and liquidity that come with this strategy, warns of potentially overcrowded treasury markets, and emphasizes the need for cautious engagement with crypto. She also sheds light on why institutions are turning to stablecoins for stability.

As one of the birthplaces of the industrial revolution, the River Mersey in northern England is no stranger to pollution flowing into its waters. Now it's got a new problem: monitoring shows the amount of forever chemicals, also known as PFAS, entering the Mersey catchment area is among some of the highest in the world.In this episode we speak to water scientist Patrick Byrne at Liverpool John Moores University in the UK about why so many per- and polyfluoroalkyl substances (PFAS), are still making it into our rivers, many from sources that are lying hidden. Identifying these sources of pollution, can help prioritise how to clean them up. This episode was produced by Mend Mariwany, Katie Flood and Gemma Ware. Sound design and mixing by Michelle Macklem and theme music by Neeta Sarl. Read the full credits for this episode and sign up here for a free daily newsletter from The Conversation.If you like the show, please consider donating to The Conversation, an independent, not-for-profit news organisation.You can be exposed to PFAS through food, water, even swimming in lakes – new maps show how risk from ‘forever chemicals’ variesAustralia has banned 3 ‘forever chemicals’ – but Europe wants to ban all 14,000 as a precautionHow I tracked the biggest hidden sources of forever chemical pollution in UK rivers – new study

Back in the 1980s, when Shimon Sakaguchi was a young researcher in immunology, he found it difficult to get his research funded. Now, his pioneering work which explains how our immune system knows when and what to attack, has won him a Nobel prize.Sakaguchi, along with American researchers Mary Brunkow and Fred Ramsdell, were jointly awarded the 2025 Nobel prize in physiology or medicine for the work on regulatory T-cells, known as T-regs for short, a special class of immune cells which prevent our immune system from attacking our own body.In this episode Sakaguchi tells The Conversation about his journey of discovery and the potential treatments it could unlock.This episode was produced by Mend Mariwany, Katie Flood and Gemma Ware. Sound design and mixing by Michelle Macklem and theme music by Neeta Sarl. Read the full credits for this episode and sign up here for a free daily newsletter from The Conversation.If you like the show, please consider donating to The Conversation, an independent, not-for-profit news organisation.Metal-organic frameworks: Nobel-winning tiny ‘sponge crystals’ with an astonishing amount of inner spaceNobel physics prize awarded for pioneering experiments that paved the way for quantum computersHow does your immune system stay balanced? A Nobel Prize-winning answerNobel medicine prize: how a hidden army in your body keeps you alive – and could help treat cancer

As Donald Trump gives oxygen to unproven theories about what might be behind a recent rise in autism cases, experts repeatedly point to the changing nature of how autism is diagnosed and viewed.A key moment in the history of autism diagnosis was the publication in 1994 of a new version of the Diagnostic and Statistical Manual of Mental Disorders. It's a reference book of psychiatric conditions and how to diagnose them, used by psychiatrists and psychologists around the world. In this episode, Andrew Whitehouse, a professor of autism research at the University of Western Australia, explains why this shift in autism diagnosis happened in the 1990s, what impact it had, and what it's meant for the support autistic people get. This episode was produced by Katie Flood, Mend Mariwany and Gemma Ware. Sound design and mixing by Michelle Macklem and theme music by Neeta Sarl. Read the full credits for this episode and sign up here for a free daily newsletter from The Conversation.If you like the show, please consider donating to The Conversation, an independent, not-for-profit news organisation.

Donald Trump is not letting up pressure on the US Federal Reserve. He's taken efforts to fire one of its governors, all the way up to the US Supreme Court. Trump's clash with the Fed echoes pressure that Richard Nixon put on the central bank in the 1970s to lower interest rates. In this episode, Cristina Bodea, professor of political science at Michigan State University, why that moment – and the inflation spike that followed – became a cautionary tale about what can happen if politicians threaten the independence of central banks. This episode was written and produced by Katie Flood and Gemma Ware with assistance from Mend Mariwany. Sound design and mixing by Eloise Stevens and theme music by Neeta Sarl. Read the full credits for this episode and sign up here for a free daily newsletter from The Conversation.If you like the show, please consider donating to The Conversation, an independent, not-for-profit news organisation.

With France, the UK, Australia and Canada expected to recognise an independent Palestinian state at UN General Assembly in New York, what are the origins of the state they plan to recognise? In this episode, Palestinian-American historian Maha Nassar from the University of Arizona describes the events leading up to the original declaration of Palestinian independence in 1988, including the compromises made within the Palestinian liberation movement. Nassar then traces how  we've got to the point where more than 150 countries will recognise an independent Palestinian state – a move that she believes is more of a symbolic gesture than a meaningful route to Palestinian sovereignty.This episode was written and produced by Mend Mariwany and Gemma Ware with assistance from Katie Flood. Sound design and mixing by Eloise Stevens and theme music by Neeta Sarl. Read the full credits for this episode and sign up here for a free daily newsletter from The Conversation.If you like the show, please consider donating to The Conversation, an independent, not-for-profit news organisation.

Police in Australia are continuing a huge manhunt in the mountains for Dezi Freeman, a man accused of killing two police officers and injuring a third in late August. Freeman identifies as a sovereign citizen, someone who believes they aren't subject to the law.In this episode we speak to criminologist Keiran Hardy from Griffith University about the origins of the sovereign citizen movement in the US, how it spread to Australia and was taken up by the self-styled Prince Leonard in the 1970s, and why the movement grew during Covid-19. This episode was written and produced by Mend Mariwany and Gemma Ware with assistance from Katie Flood and editing help from Ashlynee McGhee. Sound design and mixing by Eloise Stevens and theme music by Neeta Sarl. Read the full credits for this episode and sign up here for a free daily newsletter from The Conversation.If you like the show, please consider donating to The Conversation, an independent, not-for-profit news organisation.