PNAS Science Sessions

Modeling extreme heat waves Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Kai Kornhuber explains how and why climate models struggle to reproduce extreme heat wave trends. In this episode, we cover: •[00:00] Introduction •[00:53] Extreme weather climatologist Kai Kornhuber explains why modeling heat waves is important. •[01:38] He talks about how the study modeled hotspots of anomalous heat wave activity. •[03:01] Kornhuber tells where the hotspots are located. •[04:17] He explains how well climate models reproduce these trends. •[06:43] He talks about ways climate modelers can improve model representation of heat waves. •[07:48] Kornhuber describes the caveats and limitations of the study.  •[09:08] He enumerates the key takeaways. •[10:18] Conclusion. About Our Guest: Kai Kornhuber Senior Research Scholar International Institute for Applied Systems Analysis View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2411258121 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Reconsidering the social cost of carbon Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Frances Moore presents a re-analysis of how the social costs of carbon emissions are quantified. In this episode, we cover: •[00:00] Introduction •[00:50] Climate economist Frances Moore explains the “social cost of carbon.” •[02:21] She describes the background of the study.  •[03:35] She talks about the methods of the study, which included a survey of experts. •[05:18] Moore presents the results, including underestimation of the social cost of carbon. •[07:02] She talks about the policy implications of the study. •[08:35] Moore discusses the caveats and limitations of the study. •[09:21] Conclusion. About Our Guest: Frances Moore Associate professor University of California, Davis View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2410733121 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

How hula hoops stay aloft Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Olivia Pomerenk reveals the physics of hula hooping. In this episode, we cover: •[00:00] Introduction •[00:49] Applied mathematician Olivia Pomerenk talks about the history of hula hooping. •[01:52] Pomerenk explains the fascinating nature of hula hoop motion as well as her own personal experiences with the children’s toy. •[02:44] She describes the experimental setup with robotic hula hoopers, as well as the mathematical model that arose from experiments. •[04:44] Pomerenk enumerates the forces needed for successful hula hooping.  •[05:51] She explains how body shape affects hula hooping. •[07:17] She explores potential applications of the findings. •[08:01] Pomerenk discusses the caveats and limitations of the study. •[08:44] Conclusion. About Our Guests: Olivia Pomerenk PhD Candidate Courant Institute of Mathematical Sciences, New York University View related content here: https://www.pnas.org/doi/10.1073/pnas.2411588121 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook  LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Erosion, subsidence, and sea level rise on Arctic coastlines Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Roger Creel describes how compounding forces could reshape a thawing Arctic coastline. In this episode, we cover: •[00:00] Introduction •[00:57] Sea level geophysicist Roger Creel introduces the importance of subsidence in Arctic coastline erosion.  •[02:04] Creel describes his firsthand experiences seeing how erosion, subsidence, and sea level rise are impacting Alaskan communities. •[03:43] He explains how his model of coastline impacts was constructed. •[05:49] He describes the results of the study. •[06:43] Creel talks about the risks to coastal infrastructure. •[08:10] He lists the caveats and limitations of the study. •[08:54] Creel says that the coastline impacts may differ in different parts of the Arctic, depending on glacial history. •[09:25] He explains the takeaways from the study. •[10:39] Conclusion. About Our Guests: Roger Creel Postdoctoral scholar Woods Hole Oceanographic Institution View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2409411121 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

How brains and AI systems process moving images Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Hollis Cline describes how neuroscience informed development of an artificial intelligence movie recognition system. In this episode, we cover: •[00:00] Introduction •[00:55] Neuroscientist Hollis Cline introduces the background of the study. •[01:49] Cline talks about the current limitations of artificial intelligence movie recognition. •[02:58] She explains why Xenopus tadpoles were used as subjects in this study. •[03:29] Cline talks about the experimental setup and procedure. •[05:53] She explains the results of tadpole neurological monitoring. •[06:32] Cline adds findings about neural plasticity and learning. •[07:53] She describes how the findings led to an artificial intelligence system and the system’s capabilities. •[09:53] Caveats and limitations of the study. •[10:22] Conclusion. About Our Guests: Hollis Cline Professor Scripps Research Institute View related content here: https://www.pnas.org/doi/10.1073/pnas.2412260121 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up the Highlights newsletter

Sustainability of plant-based meat alternatives Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, researchers discuss the environmental, health, and economic tradeoffs that limit the potential benefits of plant-based meat alternatives. In this episode, we cover: •[00:00] Introduction •[01:19] Rodolphe Barrangou explains the potential opportunities and challenges for plant-based meat alternatives to help mitigate the environmental impact of meat. •[03:18] Marco Springmann compares plant-based meat and milk alternatives with both animal-sourced foods and unprocessed plant-based foods across multiple metrics. •[05:16] Bill Aimutis highlights the potential environmental impact of producing plant-based proteins. •[07:04] Ute Weisz finds significant variability in the amino acid scores and functional properties of commercially available plant protein ingredients. •[08:51] Zachary Neuhofer analyzes trends in plant-based meat alternative consumption, based on two years of grocery store scanning data. •[10:16] Evelyne Selberherr analyzes the microbial communities found in plant-based meat alternative products.  •[11:56] Matin Qaim analyzes the impact of animal-sourced foods on child nutrition in five Sub-Saharan African countries. •[13:59] Final thoughts and conclusion. About Our Guests: Rodolphe Barrangou  Todd R. Klaenhammer Distinguished Professor North Carolina State University Marco Springmann Senior Researcher | Professorial Research Fellow University of Oxford | University College London Bill Aimutis  Executive Director North Carolina Food Innovation Lab Ute Weisz  Professor Technical University of Munich Zachary Neuhofer  PhD Candidate Purdue University Evelyne Selberherr  Assistant Professor  University of Veterinary Medicine Vienna Matin Qaim  Schlegel Professor of Agricultural Economics University of Bonn View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2400495121 https://www.pnas.org/doi/full/10.1073/pnas.2319010121 https://www.pnas.org/doi/full/10.1073/pnas.2319003121 https://www.pnas.org/doi/full/10.1073/pnas.2319019121 https://www.nature.com/articles/s41598-022-16996-5 https://www.nature.com/articles/s41538-024-00269-8 https://www.pnas.org/doi/full/10.1073/pnas.2319009121 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

How Snowball Earth melted Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Shuhai Xiao explores how the Earth emerged from a planetwide glaciation called Snowball Earth. In this episode, we cover: •[00:00] Introduction •[00:48] Geobiologist Shuhai Xiao introduces us to Snowball Earth. •[01:58] Xiao introduces the “plumeworld” hypothesis that describes the end of Snowball Earth. •[03:41] He explains how lithium isotopes in rocks can confirm the plumeworld hypothesis. •[05:54] Xiao explains why dolostone deposits in China were suitable for studying this hypothesis. •[06:53] He talks about the results of the study. •[07:39] He talks about the implications of the study results. •[08:26] Caveats and limitations of the study. •[10:06] Conclusion. About Our Guests: Shuhai Xiao Professor Virginia Tech View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2407419121 Follow us on Spotify, Apple Podcasts, YouTube, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Reverse development in a comb jelly Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Joan Soto and Patel Burkhardt introduce us to a comb jelly with the ability to reverse its development to an earlier stage of life. In this episode, we cover: •[00:00] Introduction •[00:54] Marine biologist Joan-Josep Soto recounts the history of research into reverse development. •[02:27] Soto and evolutionary biologist Burkhardt introduce the comb jelly Mnemiopsis leidyi and its life stages. •[04:04] Burkhardt explains why the researchers became interested in Mnemiopsis. •[04:48] Soto describes how the researchers induced reverse development in Mnemiopsis. •[06:13] Burkhardt explores hypotheses regarding why reverse development occurs. •[07:13] Soto talks about the lessons yet to be learned from Mnemiopsis. •[09:35] Burkhardt summarizes the caveats and limitations of the study. •[10:12] Conclusion. About Our Guests: Joan-Josep Soto-Angel  Postdoctoral Scholar University Museum of Bergen Pawel Burkhadt     Group Leader Michael Sars Center, University of Bergen View related content here: https://www.pnas.org/doi/10.1073/pnas.2411499121 Follow us on Spotify, Apple Podcasts, YouTube, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Francesca Dominici, a Harvard T.H. Chan School of Public Health professor specializing in environmental health, joins researcher Luca Merlo to discuss their groundbreaking study on air pollution's impact on economic mobility. They uncover how childhood exposure to PM2.5 pollution can significantly hinder upward mobility in adulthood. The conversation reveals stark regional disparities, particularly affecting marginalized communities. They advocate for stricter air quality regulations and emphasize the need for policies that link environmental health to economic opportunities.

Kai Chen, an Associate Professor at the Yale School of Public Health, discusses the alarming health impacts of wildfire smoke pollution. He reveals that fine particulate matter (PM2.5) from these fires contributes to over 11,000 deaths annually in the U.S. Chen highlights how rising smoke levels aren't just a local issue, affecting air quality nationwide. He also examines how climate change exacerbates these health risks, particularly for vulnerable populations, underscoring the necessity for public health measures to combat this growing threat.