iiinova — where your digital self keeps evolving

Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 15/10/2026

Zwar hoffe ich, dass meine Forschung nie gebraucht wird, aber es freut mich trotzdem, wenn sie mehr Beachtung findet und wir uns dadurch hoffentlich besser auf globale Katastrophen vorbereiten. Heute ist nämlich ein Artikel in der ZEIT erschienen, der […] [Original post on fediscience.org]

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 12/10/2026

What actually makes societies more resilient against collapse? Earlier this year I spoke at the World Adaptation Forum and used the opportunity to compare the major theories of societal collapse: Limits to Growth, Structural Demographic Theory and Goliath's […] [Original post on fediscience.org]

A made up flag combining Uruguay and Norway

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 08/09/2026

After reading a lot of papers about societal collapse, I wanted a different perspective, so I turned to novels. Here's what I learned: * Novels often use collapse only as a backdrop to motivate their protagonist. * Collapse happens at the scale of systems […] [Original post on fediscience.org]

Title of the post with an old, destroyed printing press in the background.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 24/08/2026

What places on Earth are most resilient to global catastrophic risk? Our new review in Global Challenges is the first study to look at this across nuclear war, near-Earth objects, large volcanic eruptions, cyberattacks, high altitude electromagnetic pulse […] [Original post on fediscience.org]

Visual abstract of the paper that shows a Venn Diagram of which resilience factors are relevant to what kind of global catastrophe.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 21/08/2026

The failure of the food system is what gets you in almost every global catastrophe scenario. Research on making it resilient is underfunded relative to that importance. I spoke about this at the World Adaptation Forum in Budapest earlier this year. The […] [Original post on fediscience.org]

Two people sitting at a table, talking to each other during an interview.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 29/07/2026

You might remember the warnings about the ozone hole, about skin cancer and eye damage on a huge scale. You don't hear about it anymore because it largely worked. Almost all ozone depleting substances have been phased out and the ozone layer is on track to […] [Original post on fediscience.org]

An old, grainy image of a stony beach at dusk.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 01/07/2026

What happens to Europe if the AMOC collapses? The potential for much colder winters, loss of a significant part of maize and wheat agriculture, UK farmland reverting to grassland. The IPCC's confidence that this won't happen this century has decreased. In my […] [Original post on fediscience.org]

An old picture of a snowed in garden in France.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 03/06/2026

You are likely familiar with visions of doom. When I look at the news, at blog posts, at conference abstracts, all everyone ever talks about is some shade of the world ending. And I would not even necessarily disagree with them. Many things are not […] [Original post on fediscience.org]

An old locomotive that had been destroyed during the First World War.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 18/05/2026

Nuclear war is horrible and I hope it never happens. Yet, there are only a few countries that actually have nuclear weapons and the power to use them is concentrated in just a few individuals. This means the vast majority of the global population has no say […] [Original post on fediscience.org]

A world map where the countries are colored by how much of their wheat imports they would loose due a nuclear winter.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 06/05/2026

Take a guess at how many civil protection bunkers currently exist in working condition in Germany. See the first comment for the answer. The reason I'm asking is that I wrote a summary on the state of civil protection bunkers in Germany, which you can find […] [Original post on fediscience.org]

A french gun emplacement in the First World War. The soldiers are posing for the picture in their blue uniforms.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 08/04/2026

New update post for my living literature review on societal collapse: existentialcrunch.substack.com/p/ap… This means I go back to the old posts and add new papers I found, to make sure that everything stays as up to date as possible […] [Original post on fediscience.org]

An old picture of a church. The picture itself is cracked and slightly discolored in green around the cracks.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 30/03/2026

New preprint! We reviewed global catastrophic risks: nuclear war, volcanic eruptions, asteroid impacts, cyberattacks, EMP, geomagnetic storms, and pandemics. Which places on Earth are most resilient? The short answer: nowhere is safe from everything […] [Original post on fediscience.org]

Three subplots. Each showing a global map, with those countries highlighted which are resilient to different kinds of global catastrophic risk. Australia and New Zealand are the only countries present in all three risk categories.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 13/03/2026

New preprint! Global inequality is on the rise, and so is global catastrophic risk. These two problems are not independent: inequality drives societal instability and increases catastrophic risk. We show this by drawing on historical and empirical research […] [Original post on fediscience.org]

A diagram summarizing the main arguments from the paper.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 11/03/2026

Who actually shapes global risk? One common answer is to focus on individual apocalyptic actors, like terrorists aiming to end the world. But are these groups really what we should be on the lookout for most? Or should we not also consider institutional […] [Original post on fediscience.org]

Old picture from Greece of two police men who have a captured brigand with them.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 18/02/2026

New post about the state of research around nuclear war and nuclear winter, with a focus on the food system. This one's a bit different, as it was originally an invited contribution to the United Nations Independent Scientific Panel on the Effects of Nuclear […] [Original post on fediscience.org]

A picture from the First World War, showing snow covered trees, who have been damaged by explosions.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 04/02/2026

New paper is out! We identified the worst crop shock every country experienced since 1961: the global average was −29%, with Botswana even losing 80% in a single year. Climate—especially drought—was the leading cause, although conflict is also a major […] [Original post on fediscience.org]

A global map with countries being colored by the severity of their worst crop production shocks. Especially, in Africa many countries experienced severe shocks, but on other continents as well.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 29/01/2026

Had a great conversation with Samuel Arbesman on the podcast "The Orthogonal Bet" about all things collapse. If you are curious about the interdisciplinary nature of collapse studies, how it connects history to global catastrophic risk, and how societal […] [Original post on fediscience.org]

An old church, partly collapse due to bombing in the First World War.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 14/01/2026

One important factor to understanding the impact of global catastrophes is economics. How might agricultural prices rise? What are the general economic outlooks? In the next post in my living literature review I try to explore exactly this. The literature is […] [Original post on fediscience.org]

An old French poster to sell national bonds after the First World War. Golden statue in the background, ruins in the foreground.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 17/12/2025

Next round of updates for my #LivingLiteratureReview. This means I go back to the old posts and add new papers I found, to make sure that everything stays as up to date as possible. Posts which got updated this time: * Mapping out collapse research ( […] [Original post on fediscience.org]

Baguettes spread out on a table. These symbolize the bread rations in France in WW1.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 30/11/2025

For #GlobalWarming it seems that we are on a pathway to be clearly above 1.5°C and arguably also clearly above 2°C. In my new post I summarize research that highlights why this is the case and also how much of these higher temperatures ranges we really have […] [Original post on fediscience.org]

A orange tinted, old picture from an old house near a river. There are snow capped mountains in the background.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 29/10/2025

Remember the beautiful auroras last year? These occur when solar particles interact with Earth's magnetic field. When #Earth is hit by large amounts of these particles, this is called a #GeomagneticStorm. Geomagnetic storms can induce currents into the […] [Original post on fediscience.org]

A dark and small alley with houses high up on both sides. In the middle of the picture is a street lamp which is hit by sun light from the side and casts an interesting shadow on one of the buildings.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 01/10/2025

New post on my blog. I summarized Peter Turchin's book "End Times: Elites, Counter-Elites, and the Path of Political Disintegration". The post gives an overview of how #StructuralDemographicTheory works and how this explains the present political and social […] [Original post on fediscience.org]

A large, dark blue curtain halfway hiding a large, somewhat modern looking iron gate. An out of focus person is standing at the edge of the curtain.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 30/09/2025

(2/4) Even when two catastrophes cause similar global yield losses, their effects on trade are dramatically different. Abrupt sunlight reduction (#NuclearWar, #supervolcano) concentrates damage in high-latitude major exporters → severe trade disruption […] [Original post on fediscience.org]

Global map showing the distribution of relative food import losses for abrupt sunlight reduction scenarios and global catastrophic infrastructure loss. Northern Hemisphere countries in nuclear war scenario loose most.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 30/09/2025

(1/4) We modeled how global food trade would collapse after catastrophic events like nuclear war or infrastructure loss. It matters enormously where damage occurs, not just how much. Especially, in nuclear winter many countries would loose the majority of […] [Original post on fediscience.org]

A three panel figure showing the distribution of wheat trading communities now, after a nuclear war and after a loss of industrial production. The impacts of the nuclear war are considerably larger with many countries having to switch their trade community.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 04/09/2025

New preprint: "The Largest Crop Production Shocks: Magnitude, Causes and Frequency" Large #CropFailures happen regularly around the world, threatening #FoodSecurity. We analyzed sixty years of global crop production data and found that every country has […] [Original post on fediscience.org]

World map that shows the largest crop production shocks. These range from around -10 % in countries like China and up to -80% in some parts of Africa. The dataset is from 1961-2023.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 03/09/2025

#ClimateChange, #NuclearWinter, and #StratosphericAerosolInjection are all human-made interventions in the climate system. They share the potential to be massively disruptive to the habitability of this planet. Usually, we see them as separate catastrophes […] [Original post on fediscience.org]

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 06/08/2025

New theory on how #SocietalCollapse works just dropped. In his book "Goliath’s Curse: The History and Future of Societal Collapse”, @lukekemp describes how human societies repeatedly fall into the same trap: when resources become easily controlled and people […] [Original post on fediscience.org]

A worn out path vanishing into the distance. Two large elephant statues are left and right of it. In the distance you can see some mountains with a large complex at the base of them.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 24/07/2025

Have been doing some nature photography for the last two years or so. Was thinking about sharing a few here. Starting with one of my favorites. This very cute little #mouse. #Nature #Photography

A mouse hiding in leaves. Some small plants sprouting around it.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 22/07/2025

New paper is out: The State of Global Catastrophic Risk Research: A Bibliometric Review. I am quite happy with this one. I think the paper gives a nice overview of what people in the global catastrophic risk community think about and what their research […] [Original post on fediscience.org]

Visual abstract of the paper: 1) Collecting all GCR/ER papers from OpenAlex. 2) Connect them based on their reference list 3) Cluster them by similarity 4) Overview of the results

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 16/07/2025

Time for updates on my blog again. However, not only the articles, but also the infrastructure. Thanks to @rogue_scholar now every post has a DOI and can be cited. Also, to make things look nicer, every post now has its on fitting picture at the start. When […] [Original post on fediscience.org]

An old, large, iron bridge stretching in the distance over a very wide river. Lots of small boats in the foreground.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 19/06/2025

To prepare you need to know what you might face. This is true for an individual, as well as a society. To make it a bit easier to figure this out on a societal level, I aggregated a number of sources that try to assess what challenges humanity might face […] [Original post on fediscience.org]

A once beautiful, but not destroyed little church in France. Around it you can see a simple graveyard and some small houses in the background.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 21/05/2025

Preventing a #crisis is better than solving one after it happens. The challenge lies in recognizing signs early and knowing how to intervene. The latest entry in my living literature review explores three key questions: How can we detect crises before they […] [Original post on fediscience.org]

The ruins of the Roman Forum. Léon, Auguste. (1921). Italie, Rome, Forum Romain [Photograph]. Public Domain (CC-0). Inventory number: A25515S.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 16/04/2025

Time for another update in my living literature review about societal collapse: existentialcrunch.substack.com/p/ap… This time I mainly updated the posts #trade and democratic resilience (but there are more updates as well). One of my […] [Original post on fediscience.org]

Very old picture of the harbor in Constantinople. The picture is taken from up high and you can see the houses around the harbor and the large sailing ships anchoring there. Reference for the picture: Passet, Stéphane. (1912). Constantinople (actuelle Istanbul), Turquie: La Corne d'Or prise de la tour de Galata vers le port de commerce [Photograph]. Public Domain (CC-0). Inventory number: A1125.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 19/03/2025

In the research around #SocietalCollapse, once you get to the 18th century, revolutions start to pop up as a topic. To better understand the ideas and concepts important for revolutions, I read and summarized Hannah Arendt's "On #Revolution". In this she […] [Original post on fediscience.org]

Picture of a historic looking building made of white stone and a large cupola.

Passet, Stéphane. (1914). Paris VIe arr., France L'Institut de France depuis le pont des Arts [Photograph]. Public Domain (CC-0). Inventory number: A7488.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 19/02/2025

#SystemicRisk and #polycrisis are terms that are used more and more, especially in discussions around #ClimateChange. However, at least to me, they sometimes feel a bit vague and hard to pin down. So, I sat down, read a bunch of papers, and tried to create a […] [Original post on fediscience.org]

An empty conference room with old and majestic furniture design. More information about the origin of the picture: Passet, Stéphane. (1929, August 18). La Haye, Pays-Bas Binnenhof, la salle de la Conférence de la Paix [Photograph]. Public Domain (CC-0). Inventory number: A61808.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 15/01/2025

During my research around #SocietalCollapse, one thing that comes up again and is economic #inequality. It seems that there is something about it that makes societies inherently less stable and less able to tackle challenges ahead. To explore this more, I […] [Original post on fediscience.org]

A view on the port in Algier. Photo cred: "Alger , Algérie Vue panoramique du port" by Jules Gervais-Courtellemont (1909-1911). Source: Musée Départemental Albert-Kahn. CC-00- Public Domain.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 14/01/2025

In the last few days the news focused a lot on the fact that #2024 was the first year where we went above #1.5°C. This made me want to highlight a paper again where I was the main author in 2022. In this paper we looked at what temperatures the #IPCC reports […] [Original post on fediscience.org]

Scientific figure which shows for each assessment report since 1990 how it focused on temperatures in the range between 0.5°C and 10 °C. The figure shows that the first four reports had a similar focus, with lots of research on higher temperatures, but that this trend shifted with the last two reports and is now mostly focused on 1.5°C and 2°C.

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Florian U. Jehn @florianjehn.fediscience.org.ap.brid.gy · 04/12/2024

Happy to share our new #preprint—the first-ever #SystematicReview on global catastrophic risk. 🌍 We explores the growing field of #GlobalCatastrophicRisk and #ExistentialRisk, which focus on global threats like #NuclearWar. This bibliometric analysis shows […] [Original post on fediscience.org]

A visual summary of the preprint, which highlights how the methods were done and what the main findings are. It contains the same information as the abstract of the preprint.

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