Prof. Stefan Rahmstorf
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rahmstorf.bsky.social
Prof. Stefan Rahmstorf
@rahmstorf.bsky.social

Climate scientist, professor of Physics of the Oceans in Potsdam. Opinions my own.

Stefan Rahmstorf is a German oceanographer and climatologist. Since 2000, he has been a Professor of Physics of the Oceans at Potsdam University. He studied physical oceanography at Bangor University and received his Ph.D. in oceanography from Victoria University of Wellington (1990). His work focuses on the role of ocean currents in climate change. He was one of the lead authors of the IPCC Fourth Assessment Report. .. more

Environmental science 46%
Geology 21%

Giving in to authoritarianism rather than sticking up for free speech. What has become of the BBC?
I wish I didn’t have to share this. But the BBC has decided to censor my first Reith Lecture.

They deleted the line in which I describe Donald Trump as “the most openly corrupt president in American history.” /1

It should be obvious by now that we cannot make the future of human civilisation dependent on whether the fossil fuel vendors vote for ending fossil fuel use.
Rather, it is up to those who buy fossil fuels to end their lethal addiction fast, before it is too late.
My latest: #COP30, global climate politics, and what happens next — for @theguardian.com

www.theguardian.com/commentisfre...

I wish I didn’t have to share this. But the BBC has decided to censor my first Reith Lecture.

They deleted the line in which I describe Donald Trump as “the most openly corrupt president in American history.” /1

Reposted by Stefan Rahmstorf

My latest: #COP30, global climate politics, and what happens next — for @theguardian.com

www.theguardian.com/commentisfre...

When a government speaks responsibly about climate risks. Iceland's climate minister Jóhannsson:
"We believe that confronting climate tipping points and the risks they pose openly is not a sign of 'pessimism' or 'alarmism' but a sign of realism and responsibility."
youtu.be/B-0eQnEEsYA?...
After COP30 Fire and Floods: AMOC Shutdown
YouTube video by International Cryosphere Climate Initiative
youtu.be

The sea surface is not horizontal; its slope is influenced by ocean currents and the density distribution.

The sea surface is not horizontal; its slope is influenced by ocean currents and the density distribution.

“… because ignoring systemic risk is unacceptable!”
Iceland’s climate minister in Belém on the risk of major #AMOC changes.
“Prevention remains our first duty.”
Listen to him (and my talk 🌊) here:
youtu.be/B-0eQnEEsYA?...
The first 2 mins show how the live stream was ended by a 🔥.
After COP30 Fire and Floods: AMOC Shutdown
YouTube video by International Cryosphere Climate Initiative
youtu.be

And of course there’s the extra sea-level rise, by half a meter or more. bsky.app/profile/rahm...
It further shows a similar sea-level rise pattern after #AMOC shutdown as we found in Levermann et al. 2005, with the dynamic rise extending down into the South Atlantic. (That would be added to any global rise caused by climate warming.) 🧵
➡️ agupubs.onlinelibrary.wiley.com/doi/full/10....

Reposted by Peter Stoett

Many people think about cold in Northern Europe if the Atlantic Ocean current system #AMOC fails. But that wouldn’t be the only problem for Europe by far.
This new study shows that severe drought is another one. 🌊
📢 New paper on the impacts of AMOC collapse on European hydroclimate. 🌊

We find an AMOC collapse would exacerbate drought conditions across Europe, linked to reduced precipitation. In combination with climate change droughts are expected to become more frequent and severe.

doi.org/10.5194/hess...
Changing European hydroclimate under a collapsed AMOC in the Community Earth System Model
Abstract. The Atlantic Meridional Overturning Circulation (AMOC) is expected to weaken or even collapse under anthropogenic climate change. Given the importance of the AMOC in the present-day climate,...
doi.org

📢 New paper on the impacts of AMOC collapse on European hydroclimate. 🌊

We find an AMOC collapse would exacerbate drought conditions across Europe, linked to reduced precipitation. In combination with climate change droughts are expected to become more frequent and severe.

doi.org/10.5194/hess...
Changing European hydroclimate under a collapsed AMOC in the Community Earth System Model
Abstract. The Atlantic Meridional Overturning Circulation (AMOC) is expected to weaken or even collapse under anthropogenic climate change. Given the importance of the AMOC in the present-day climate,...
doi.org

Hey Murdoch fake-news media! The study you report on here
1. Predicts nothing but is about the past.
2. Is not about Gulf Stream but #AMOC.
3. An AMOC collapse wouldn’t cause an Ice Age.
Incompetence or intent to confuse?
The study by Ren et al shows AMOC has weakened: www.nature.com/articles/s43...

While the Reuters report says an AMOC shutdown "could trigger a modern-day ice age", this is not what we scientists call an ice age. Rather, it is a regional cooling, plus other severe impacts on sea level, rainfall patterns, weather extremes, marine ecosystems and ocean carbon uptake.
Iceland Climate Minister Johannsson: "It is a direct threat to our national resilience and security. (This) is the first time a specific climate-related phenomenon has been formally brought before the National Security Council as a potential existential threat."
www.reuters.com/sustainabili...
Iceland deems possible Atlantic current collapse a security risk
Iceland has designated the potential collapse of a major Atlantic Ocean current system a national security concern and an existential threat, enabling its government to strategize for worst-case scenarios, the country's climate minister told Reuters.
www.reuters.com

A funny postscript: when I was a young postdoc in the 1990s I was told by a professor that using colour graphics wasn't serious science.
And that only bad scientists speak to journalists.

A little reminder of science history: air temperature change after a shutdown of the Atlantic overturning circulation #AMOC, as simulated in climate models 36 years apart.
Suki Manabe went on to win the physics Nobel prize in 2021 jointly with his colleagues Klaus Hasselmann and Giorgio Parisi.

Reposted by Stefan Rahmstorf

I wouldn't board an aircraft, a bus, a train, a ship or even get in a car that had a 5% chance of crashing. Now AMOC collapse is closing in on over 25% probability we are all being boarded to a mad future.
Excellent eye opener of a presentation. Educate yourself, watch it.
youtu.be/ULJXqOZuY-8
Is the Atlantic Ocean circulation close to tipping?
YouTube video by Earth System Analysis - Potsdam Institute
youtu.be

Reposted by Stefan Rahmstorf

I found the link for your article mentioned at the end of your presentation, which details further possible consequences of AMOC shutdown. Thank you for your hard work.
tos.org/oceanography...
tos.org

The government of Iceland now considers this a national security threat. www.arctictoday.com/iceland-sees...
And the Foreign Intelligence Service of Germany together with other German institutions published a National Climate Risk Assessment this year.
Here is what it says about #AMOC tipping risk.
Is the Atlantic Ocean circulation close to tipping?
Hear the latest science as I presented it last month at the ATLAS25 event in Helsinki.
Let me know if anything is unclear, or if you see good reasons why your government shouldn't immediately act on this. 🌊
youtu.be/ULJXqOZuY-8
Is the Atlantic Ocean circulation close to tipping?
YouTube video by Earth System Analysis - Potsdam Institute
youtu.be

Reposted by Peter M. Cox

In 2024, renewable energy accounted for over 90% of global power capacity expansion. That is because it makes economic sense. IRENA_DAT_RE_Capacity_Highlights_2025-1.pdf

Reposted by Jože P. Damijan

Reposted by Stefan Rahmstorf

Starke Rede, danke auch für die Quellen!

Hier ein direkt klickbarer Link:

www.pik-potsdam.de/~stefan/FFFD...
www.pik-potsdam.de

Reposted by Stefan Rahmstorf

#Klimakatastrophe #UK now:

#flood#storm#uk#claudiastorm#wales#birmingham#nottingham

A powerful surge of heavy rain from Storm Claudia has swept across the United Kingdom, triggering widespread flooding from Wales to the Midlands.

youtu.be/XfObiOczPA8?...
Chaos in the UK Today: Storm Claudia Causes Severe Flooding in Wales, Birmingham and Nottingham!
YouTube video by NDH Weather
youtu.be