Of climate models and trust

Of climate models and trust

Today’s episode dives into one of the biggest questions in climate science: How much can we trust future climate projections? Climate models are powerful tools, but they’re not crystal balls. To understand what they can tell us, and also where their limits lie, we explore how these models work, why uncertainty is built into them, and what that means for interpreting their results. We break down the key sources of uncertainty, from the chaotic nature of the Earth system to the assumptions scientists must make about future emissions, land use, and population growth. These choices shape the scenarios that models simulate, and ultimately the futures they reveal. But don't you worry! When all these factors are accounted for, our climate models are a great resource to understand our possible futures. Don't hesitate to contact us in case you have questions, or with suggestions for further research and podcast episodes on the topic (lennard.montag@uol.de [(lennard.montag@uol.de], www.linkedin.com/in/lennard-montag) [https://www.linkedin.com/in/lennard-montag]). RESOURCES: CarbonBrief's climate modelling explainers: * History of climate modelling https://www.carbonbrief.org/timeline-history-climate-modelling/ [https://www.carbonbrief.org/timeline-history-climate-modelling/] * How do climate models work? https://www.carbonbrief.org/qa-how-do-climate-models-work/ [https://www.carbonbrief.org/qa-how-do-climate-models-work/] * Can we trust models: https://www.carbonbrief.org/can-we-trust-climate-models/ [https://www.carbonbrief.org/can-we-trust-climate-models/] Model comparison against observations – RealClimate posts by Gavin Schmidt and colleagues: https://www.realclimate.org/index.php/archives/2019/12/how-good-have-climate-models-been-at-truly-predicting-the-future/ [https://www.realclimate.org/index.php/archives/2019/12/how-good-have-climate-models-been-at-truly-predicting-the-future/] https://www.realclimate.org/index.php/climate-model-projections-compared-to-observations/ [https://www.realclimate.org/index.php/climate-model-projections-compared-to-observations/] Information about CMIP6 Geoengineering and Carbon Removal Model Intercomparison Project (MIP): Keller, D. P., Lenton, A., Scott, V., Vaughan, N. E., Bauer, N., Ji, D., Jones, C. D., Kravitz, B., Muri, H., and Zickfeld, K.: The Carbon Dioxide Removal Model Intercomparison Project (CDR-MIP): Rationale and experimental protocol for CMIP6, Geosci. Model Dev., https://doi.org/10.5194/gmd-2017-168 [https://doi.org/10.5194/gmd-2017-168], 2018. Kravitz, B., Robock, A., Tilmes, S., Boucher, O., English, J. M., Irvine, P. J., Jones, A., Lawrence, M. G., MacCracken, M., Muri, H., Moore, J. C., Niemeier, U., Phipps, S. J., Sillmann, J., Storelvmo, T., Wang, H., and Watanabe, S.: The Geoengineering Model Intercomparison Project Phase 6 (GeoMIP6): simulation design and preliminary results, Geosci. Model Dev., 8, 3379-3392, doi:10.5194/gmd-8-3379-2015, 2015 Lennartz, S. T., Keller, D. P., Oschlies, A., Blasius, B., & Dittmar, T. (2024). Mechanisms underpinning the net removal rates of dissolved organic carbon in the global ocean. Global Biogeochemical Cycles, 38, e2023GB007912. https://doi.org/10.1029/2023GB007912 [https://doi.org/10.1029/2023GB007912] Information about the emission scenarios – old and new: https://open.substack.com/pub/theclimatebrink/p/on-the-death-of-rcp85?utmcampaign=post-expanded-share&utmmedium=web [https://open.substack.com/pub/theclimatebrink/p/on-the-death-of-rcp85?utm_campaign=post-expanded-share&utm_medium=web]

Of super(duper)models and 'l@s nin@s'

Today's episode is all about the El Niño Southern Oscillation (ENSO), a recurring pattern in the tropical Pacific. It is characterised by a cyclic pattern of warm and cold events, El Niño and La Niña. These have globally felt impacts, necessitating good predictions and a better understanding of its processes. This is the topic of Lennard's master thesis in which an interactively coupled modelling system, also referred to as a Supermodel, is evaluated for its ability to simulate the ENSO. Update: ENSO is for this year again projected to develop into a strong El Niño event. The NOAA expects an El Niño with ca. 60% probability and even 25% for a strong El Niño for the late year 2026. Don't hesitate to contact Lennard in case you have questions, or with suggestions for further research and podcast episodes on the topic (lennard.montag@uol.de [(lennard.montag@uol.de], www.linkedin.com/in/lennard-montag) [https://www.linkedin.com/in/lennard-montag]). RESOURCES: Information about ENSO … Bayr, T., & Latif, M. (2023). ENSO atmospheric feedbacks under global warming and their relation to mean-state changes. Climate Dynamics, 60(9-10), 2613–2631. https://doi.org/10.1007/s00382-022-06454-3 [https://doi.org/10.1007/s00382-022-06454-3] McPhaden, M. J., Santoso, A., & Cai, W. (2020). Introduction to El Niño Southern Oscillation in a Changing Climate: 1. In El Niño Southern Oscillation in a Changing Climate (pp. 1–19). American Geophysical Union (AGU). https://doi.org/10.1002/9781119548164.ch1 [https://doi.org/10.1002/9781119548164.ch1] Williams, A., Santoro, C. M., Smith, M. A., & Latorre, C. (2008). THE IMPACT OF ENSO IN THE ATACAMA DESERT AND AUSTRALIAN ARID ZONE: EXPLORATORY TIME-SERIES ANALYSIS OF ARCHAEOLOGICAL RECORDS . Chungara: Revista de Antropología Chilena, 40, 245–259. http://www.jstor.org/stable/27802523 [http://www.jstor.org/stable/27802523] … and the SuMo: Counillon, F., Keenlyside, N., Wang, S., Devilliers, M., Gupta, A., Koseki, S., & Shen, M.-L. (2023). Framework for an Ocean–Connected Supermodel of the Earth System. Journal of advances in modeling earth systems, 15(3). https://doi.org/10.1029/2022MS003310 [https://doi.org/10.1029/2022MS003310] Duane, G. S., & Shen, M.-L. (2023). Synchronization of Alternative Models in a Supermodel and the Learning of Critical Behavior. Journal of the Atmospheric Sciences, 80(6), 1565–1584. https://doi.org/10.1175/JAS-D-22-0113.1 [https://doi.org/10.1175/JAS-D-22-0113.1] Schevenhoven, F., Keenlyside, N., Counillon, F., Carrassi, A., Chapman,W. E., Devilliers, M., Gupta, A., Koseki, S., Selten, F. M., Shen, M.-L., Wang, S., Weiss, J. B., Wiegerinck, W., & Duane, G. S. (2023). Supermodeling: Improving Predictions with an Ensemble of Interacting Models. Bulletin of the American Meteorological Society, 104(9), E1670–E1686. https://doi.org/10.1175/BAMS-D-22-0070.1 [https://doi.org/10.1175/BAMS-D-22-0070.1]

Of sea-ice models and phytoplankton

In this episode, Charlotte walks us through her research on how differences in sea ice models affect the biological processes in an Arctic ocean model. She breaks down how sea ice influences phytoplankton dynamics in the real world and in numerical model simulations. If you're navigating your own thesis project or feeling the pressure of an approaching deadline, the episode closes with a dose of support and motivation to help you keep going! Update: As the planet keeps turning, NOAA’s latest Arctic Report Card (December 2025) revealed that March 2025 marked the lowest annual Arctic maximum sea ice extent in the 47 years of available satellite record. Don't hesitate to contact Charlotte in case you have questions, or with suggestions for further research and podcast episodes on the topic (a83350@ualg.pt [(a83350@ualg.pt], www.linkedin.com/in/charlotte-walter-6930791aa) [https://www.linkedin.com/in/charlotte-walter-6930791aa]). RESOURCES **Arctic amplification ** Rantanen, M., Karpechko, A. Y., Lipponen, A., Nordling, K., Hyvärinen, O., Ruosteenoja, K., Vihma, T., & Laaksonen, A. (2022). The Arctic has warmed nearly four times faster than the globe since 1979. Communications Earth & Environment, 3, 168. doi:10.1038/s43247-022-00498-3. **Arctic sea ice extent ** NOAA Arctic Report Card 2024: Sea Ice. Meier, W. N., Petty, A., Hendricks, S., Bliss, A., Kaleschke, L., Divine, D., Farrell, S., Gerland, S., Perovich, D., Ricker, R., Tian-Kunze, X., Webster, M. https://doi.org/10.25923/aksk-7p66 [https://doi.org/10.25923/aksk-7p66]. NOAA Arctic Report Card 2025: Sea Ice. Meier, W. N., Petty, A., Hendricks, S., Bliss, A., Kaleschke, L., Divine, D., Farrell, S., Gerland, S., Perovich, D., Ricker, R., Tian-Kunze, X., Webster, M. https://doi.org/10.25923/mmxf-0r86 [https://doi.org/10.25923/mmxf-0r86]. **Increase in Arctic biomass production ** Lewis, K. M., Van Dijken, G. L., & Arrigo, K. R. (2020). Changes in phytoplankton concentration now drive increased Arctic Ocean primary production. Science, 369, 198–202. doi:10.1126/science.aay8380. Timmermans, M.-L., & Marshall, J. (2020). Understanding Arctic Ocean Circulation: A Review of Ocean Dynamics in a Changing Climate. Journal of Geophysical Research: Oceans, 125, e2018JC014378. doi:10.1029/2018JC014378. **Sea ice models ** Ólason, E., Boutin, G., Williams, T., Korosov, A., Regan, H., Rheinlænder, J., Rampal, P., Flocco, D., Samaké, A., Davy, R., Spain, T., & Chua, S. (2025). (PREPRINT) The next generation sea-ice model neXtSIM, Version 2. doi:10.5194/egusphere-2024-3521. Hunke, E. C., Lipscomb, W. H., Turner, A. K., Jeffery, N., & Elliott, S. (2015). CICE: The Los Alamos Sea Ice Model Documentation and Software User’s Manual Version 5.1 (LA-CC-06-012).

ECOPs and numerical modeling

During this weeks episode, we are meeting you on a personal note, talking about our educational backgrounds and paths to become ECOPs. Why did we choose to study the marine environment? How did we manage so far? And what are we planning to do next? We will share some experiences on how to find master thesis topics and funding for research internships abroad. And yes, we go there: we will share how we describe numerical modelling to our families, and how models can be very cool! A tiny spoiler: this won’t be the last time you hear us talk about them. Helpful links: • Nansen Environmental and Remote Sensing Center (https://nersc.no/ [https://nersc.no/]; last accessed: 10.12.2025) • Webpage for M.Sc. Environmental Modelling at Carl-von-Ossietzky University Oldenburg (https://uol.de/ummo-msc [https://uol.de/ummo-msc]; last accessed: 08.01.2026) • Webpage Marine and Coastal Systems, University of Algarve (https://www.ualg.pt/en/curso/1740 [https://www.ualg.pt/en/curso/1740]; last accessed: 08.01.2026) • "All models are wrong but some are useful."; Box, G.E.P. "Robustness in the Strategy of Scientific Model Building." Robustness in Statistics, edited by Robert L. Launer and Graham N. Wilkinson, Academic Press, 1979, pp. 201- 36. ScienceDirect. Contact: Lennard: * Lennard.montag@uol.de [Lennard.montag@uol.de] * www.linkedin.com/in/lennard-montag [https://www.linkedin.com/in/lennard-montag] Charlotte * a83350@ualg.pt [a83350@ualg.pt] * www.linkedin.com/in/charlotte-walter-6930791aa [https://www.linkedin.com/in/charlotte-walter-6930791aa]

Ocean Myths, Legends and Tales

No matter where you go, there will always be a tale about the ocean; whether it is to warn you about danger, to share the story of the community or to teach a lesson, ocean storytelling has always been present in the heart of our coastal societies. On this episode of GenSea, Joelle, Charlotte, Lennard and Gilbers sit around to share different stories coming from very different parts of the world like Greece, Japan, Scotland and the pacific ocean to illustrate that everywhere on the world, there will always be an ocean story to be told, you just to ask about it. First, Charlotte will talk to us about Greek myths and how they influenced Mediterranean cultures and what is known as western society. Who hasn’t heard of Poseidon and the oceanids ? Then, Joelle takes us to the other side of the world to share with us how Japanese folklore found an explanation to the catastrophic earthquakes and tsunamis they sustained thanks to an enormous fish that doesn’t come often to the surface. Afterwards, Lennard tells us about how Polinesian people explained the phenomenon of a vanished island on the pacific ocean. Atlantis, is that you ?. Lastly, Gilbers takes us to Scotland and Ireland, where the tale of the selkie people came to be. If you see a seal, be aware, because you might fall in love with its human version. As the episode is wrapped up, the importance of storytelling is brought to the table as well the importance of keeping myths, legends and tales alive as they define a society, specially a coastal one. This episode is a handover episode to let the floor to your new host for the next months, Lennard and Charlotte, two great scientists with a lot of great new topics to bring to the table. Joelle and Gilbers will come back later in the year and thank every single listener they have had over the last few months as well as all their invites. Keep connected for more!