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Florian U. Jehn

@florianjehn.fediscience.org.ap.brid.gy
13 followers 1 following 53 posts

Aggressively agreeable | currently exploring the overlap of #ExistentialRisk, #FoodSecurity, #NuclearWinter and #Collapse | also quite interested in […] 🌉 bridged from fediscience.org/@florianjehn on the fediverse by fed.brid.gy

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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
qbi @qbi.freie-re.de.ap.brid.gy · 29/08/2026
Ich feiere das Video von Wayne #Carpendale gerade sehr. #AfD #noafd
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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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.
121
Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
Joe Roe @joeroe.archaeo.social.ap.brid.gy · 09/02/2026
‘AltMetric’-style services, which track citations to academic papers outside of academic literature—so in the news, social media, etc.—have been quick to incorporate #BlueSky posts, but I’ve yet to see one that includes the #fediverse I can see that (real) decentralisation makes it harder to […]
archaeo.social
Original post on archaeo.social
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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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
Bruce Lawson ✅ ♫ ♿ ✌️♂️✊ @brucelawson.vivaldi.net.ap.brid.gy · 31/10/2025
"In August 2025, Google announced that starting next year, it will no longer be possible to develop apps for the Android platform without first registering centrally with Google." What tis means for your rights, and how you can help: keepandroidopen.org
keepandroidopen.org
Keep Android Open
Advocating for Android as a free, open platform for everyone to build apps on.
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Reposted by Florian U. Jehn
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 · 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 · 11/10/2025
I have written a new draft for my blog about the potential damages that can be caused by a #GeomagneticStorm. I am looking for someone familiar with this topic to review it for accuracy. If this is you, please write me a message. If this is not you, please consider boosting this message.
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Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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 · 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.
111
Reposted by Florian U. Jehn
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 · 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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Reposted by Florian U. Jehn
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]
Abandoned trenches in the desert.
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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]
Abandoned trenches in the desert.
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Reposted by Florian U. Jehn
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 · 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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