Episodes

In this Climate Chat episode, we interview The Lightsmith Group co-founder and Managing Director Sanjay Wagle about his firm's focus on investing in climate adaptation and resilience opportunities. Sanjay Wagle is co-founder and Managing Director of The Lightsmith Group, a private equity firm investing in growth-stage technology companies that address critical societal needs, with a current focus on climate change adaptation and resilience. Sanjay is also a member of the board of the Woodwell Cl...

In this Climate Chat episode, Climate Chat hosts Dan Miller and Leon Simons discuss the unintended consequences of reducing fossil fuel emissions and the problems of pursuing a "emissions reduction only" approach to addressing climate change. Leon Simons' 2023 LinkedIn post: "Unintended consequences of cleaning up our mess": https://www.linkedin.com/pulse/unintended-consequences-cleaning-up-our-mess-leon-simons/?trackingId=qavCmSFGQWiYHfM%2FV1t%2FhQ%3D%3Dhttps%3A%2F%2Fwww.linkedin.com%2Fpulse%2F...

In this Climate Chat episode, We interview Andrew Hultgren about his recent paper in the journal Nature, "Impacts of climate change on global agriculture accounting for adaptation." The paper concludes that there will be significant drops in agriculture productivity under global warming even with adaption measures. Surprisingly, negative impacts are larger in developed countries with advanced agriculture practices. Andrew Hultgren is an environmental and Industrial Organization economist studyin...

In this Climate Chat episode, We interview Ben Carey, the co-founder of the Utopia Bureau, a climate communications lab, prototyping innovative ways to trigger climate action urgently and at scale. Its approach is to help tip social norms across multiple fronts. Its founders are Ben Carey and Henrik Delehag, authors and ex-advertising creative directors. They draw on a wide network of strategic, creative, production, media, and activist help depending on the project. Work so far has featured on ...

In this Climate Chat episode, We interview Shantanu Agarwal, the CEO of Mati Carbon which was the Grand Prize winner of the Carbon Removal XPrize. Mati spreads crushed basalt rocks on farmer fields in the global south which improves soil quality and the crushed rock absorbs CO2 which earns carbon removal credits. Shanatanu Agarwal is an experienced climate tech serial entrepreneur with more than 20 years of industry experience. He has founded multiple successful startups and nonprofits in the en...

In this Climate Chat episode, Climate Chat hosts Dan Miller and Leon Simons discuss the upcoming report: "Indicators of Global Climate Change 2024: annual update of key indicators of the state of the climate system and human influence" which is in pre-print for the journal Earth System Science Data (ESSD). We will also discuss climate change indicators that are not included in the report. Link to pre-print: https://essd.copernicus.org/preprints/essd-2025-250/ Please Like and Subscribe! Dan Mille...

In this Climate Chat episode, we interview University of Michigan Professor Kaitlin Raimi about her research on public perception of climate change and climate solutions such as carbon capture and sunlight reflection methods (SRM). Kaitlin Raimi is an associate professor of public policy at the University of Michigan Ford School. As a social/environmental psychologist, her interests center on how individuals can promote or prevent sustainable behaviors and policies. She has three broad areas of ...

In this Climate Chat episode, we answer viewer questions. Please post your questions ahead of the live program on X/Twitter or Bluesky. During the livestream, you can post questions via the YouTube comments (please preface your question with "Question:"). Please Like and Subscribe! Dan Miller has been giving talks around the world on the need for urgent climate action for over 20 years. He is co-founder of The Roda Group, a climate-tech venture capital group, and he serves as an advisor for othe...

In this Climate Chat episode, we interview returning guest René van Westen on his latest Atlantic Meridional Overturning Circulation (AMOC) research. Dr. Westen is a postdoctoral researcher at Utrecht University in the Netherlands. René is the author of a number of recent scientific papers on AMOC including the following: Substantial Risk of 21st Century AMOC Tipping even under Moderate Climate Change: https://arxiv.org/abs/2407.19909 Collapse of the Atlantic Meridional Overturning Circulation i...

In this Climate Chat episode, hosts Dan Miller & Leon Simons discuss warming trends and what they say about when the Earth will cross the 2ºC warming threshold. We will also discuss the latest communications from climate scientist James Hansen on cloud feedbacks and what that means for near-term global warming. Link to James Hansen's communication: "Large Cloud Feedback Confirms High Climate Sensitivity": https://www.columbia.edu/~jeh1/mailings/2025/CloudFeedback.13May2025.pdf Please Like and Su...

In this Climate Chat episode, Dan Miller presents the second half of a lecture he gave recently at the Middlebury Institute of International Studies in Monterey. This talk is on why climate policies fail and highlights the mistakes made when developing climate policies and ends with a set of policies that would seriously address the climate crisis. Please Like and Subscribe! Link to first half of the lecture: Climate Science Update (abridged): https://youtu.be/W0Maq2HeJSI Related Climate Chat pr...

In this Climate Chat episode, Leon Simons reports on the European Geosciences Union (EGU) 2025 General Assembly meeting that ended Friday. Please Like and Subscribe! Link to EGU 2025 website: https://www.egu25.eu Leon Simons is a climate scientist based in the Netherlands. He was a co-author with James Hansen on the 2023 "Global Warming in the Pipeline" paper that discussed the recent acceleration in global warming. Leon's work has focused recently on changes in aerosol emissions from ships and ...

In this Climate Chat episode, Cornell climate scientist -- and returning guest -- Douglas MacMartin discusses a research paper he co-authored that says Sunlight Reflection Methods (a.k.a, solar radiation management - SRM) can stop the weakening of the Atlantic Meridional Overturning Circulation (AMOC), which is the ocean "conveyor belt" that transports warm water from the tropics to northern Europe. Link to pre-print paper: "Stratospheric Aerosol Injection could prevent future Atlantic Meridiona...

In this Climate Chat episode, Dan Miller presents an update on the latest climate science, with an emphasis on the recent research from climate scientist James Hansen as well as NASA scientist George Tselioudis. This presentation is based on a lecture that Dan gave recently at the Middlebury Institute of International Studies at Monterey. Note: This abridged version does not include Q&A at the end. See the unabridged version if you want to hear the Q&A: https://youtube.com/live/MYUuzNkXxYE Relat...

In this Climate Chat episode, we talk with Dana Fisher, author of "Saving Ourselves: From Climate Shocks to Climate Action," about what it will take to get the public to demand climate action and get policymakers to listen to them. Dana R. Fisher is the Director of the Center for Environment, Community, & Equity and Professor in the School of International Service at American University. She currently serves as a Non Resident Senior Fellow in the Governance Program at the Brookings Institution, ...

In this Climate Chat episode, Leon Simons and Dan Miller will discuss how the IPCC treats CO2 and aerosol emissions differently and how that leads to an underestimation of climate impacts. Link to posts on this subject: https://bsky.app/profile/leonsimons.bsky.social/post/3lljyjnclts2a https://x.com/ryankatzrosene/status/1905326300363194478 Many other Climate Chat programs on accelerated warming, AMOC collapse, SRM, etc.: https://www.youtube.com/@climatechat/streams Please Like and Subscribe! Le...

In this Climate Chat episode, we interview Climate Defiance founder and executive director Michael Greenberg on the organization's goals, tactics, and successes, and how their strategy may change given the current administration's attacks on climate action and science. Michael Greenberg is the founder and executive director of Climate Defiance. His work focuses on resisting new fossil fuel infrastructure and making climate change a top issue in American politics. Michael and the team’s work has ...

In this Climate Chat episode, we interview Dr. Vincent Gauci on how reducing air pollution results in increased atmospheric methane concentrations. Vincent Gauci is professor of Geography and Environmental Sciences and a Birmingham Professorial Fellow at the University of Birmingham in the UK. Professor Gauci investigates how the biosphere interacts with the atmosphere and he explores questions relating to how these interactions respond to various drivers of global change. Article in The Convers...

In this Climate Chat episode, we interview Dr. Peter Gleick on the impact that climate change is having, and will have, on water, including water availability, floods, droughts, extreme rainfall, water-driven conflict, and "peak water." Dr. Peter Gleick is a leading scientist, innovator, and communicator on water and climate issues. He co-founded the Pacific Institute in Oakland,California in 1987, one of the most innovative, independent non-governmental research centers, creating and advancing ...

In this Climate Chat episode, we discuss the issue of ecological footprint overshoot and climate change with Professor William E. Rees. William Rees is a bio-ecologist, ecological economist, former Director and Professor Emeritus of the University of British Columbia’s School of Community and Regional Planning. His early research focused on environmental assessment but gradually extended to the biophysical requirements for sustainability and the implications of global ecological trends. Along th...

In this Climate Chat episode, I will interview returning guest David Fenton, a Climate Communications Expert & Activist, about the failure of the climate community to engage the public and how we can get the public to demand action on climate change. David founded the largest Public Relations firm focused on social causes, Fenton Communications. After retiring from the firm, David is dedicating his efforts to engaging the public and policymakers on climate change. Over the years, David's clients...

In this Climate Chat episode, Leon Simons and I will discuss the new communication by James Hansen titled "The Acid Test: Global Temperature in 2025" In his message, Hansen discusses what current temperatures say about his theory on why the global temperature has accelerated in recent years. Leon and I will also make an announcement about upcoming enhancements to the Climate Chat channel. Link to Hansen's "The Acid Test: Global Temperature in 2025" communication: https://www.columbia.edu/~jeh1/m...

In this Climate Chat episode, we speak with Citizens' Climate Lobby's (CCL) Research Coordinator, Dana Nuccitelli, about what CCL does and how it is going to navigate the political environment that is moving away from climate action and science in general. Citizens’ Climate Lobby is a nonprofit, nonpartisan, grassroots advocacy climate change organization focused on national policies to address the national and global climate crisis. Dana Nuccitelli is an environmental scientist and climate jour...

In this Climate Chat episode, Leon Simons and I will discuss the new paper by James Hansen, et al, titled "Global Warming Has Accelerated: Are the United Nations and the Public Well-Informed?" In the paper, Hansen discusses how the recent IMO regulations on ship emissions were a significant contributor to the recent acceleration in global warming. The paper more broadly shows that aerosols are a significant factor in climate change and their impact is underestimated by the United Nations Intergo...