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%

Reposted by Wolfgang Huber

Guter Tag um an @hateaid.org zu spenden, habe das auch gerade schnell erledigt.

hateaid.org

Reposted by Stefan Rahmstorf

Astonishing feat!
US will break its record for the warmest Christmas by ~5°F! That’s remarkable.
Anomalies are up to +40°F in the nation’s middle and as you can see the US has the warmest air - relative to average - in the World!
H/T to @BenNollWeather

Except here different ocean regions (e.g. the Nordic Seas) are treated as a box of sea water. In fact two vertically stacked boxes for upper ocean and deep ocean.

Hey, let me know which screenshot from our paper you prefer! Happy holidays 😃!

Some consider the lack of weakening of the currents between Atlantic and Nordic Seas an argument against an ongoing #AMOC weakening.
Here we show why the opposite is true: AMOC weakening causes a temporary increase in Nordic Seas overturning. 🌊
egusphere.copernicus.org/preprints/20...
Nordic Overturning Increases as AMOC Weakens in Response to Global Warming
Abstract. The Atlantic Meridional Overturning Circulation (AMOC) is weakening in response to global warming, while Nordic Seas Overturning Circulation (NOC) is projected to increase. So far, no causal...
egusphere.copernicus.org
So the US administration considers hate speech and disinformation “American viewpoints“? 🙄
HateAid is an organization that also helps climate scientists to defend themselves against online abuse and threats.
Its founder was awarded the Order of Merit of the Federal Republic of Germany 🇩🇪 this year.
“Imran Ahmed, chief executive of Centre for Countering Digital Hate; Josephine Ballon and Anna-Lena von Hodenberg, leaders of HateAid, a German organization; former EU Commissioner Thierry Breton, who was responsible for digital affairs; and Clare Melford, who runs the Global Disinformation Index.”
US bars five Europeans it says pressured tech firms to censor American viewpoints online
The State Department is barring five Europeans it accuses of leading efforts to pressure U.S. tech firms to censor or suppress American viewpoints.
apnews.com
“Imran Ahmed, chief executive of Centre for Countering Digital Hate; Josephine Ballon and Anna-Lena von Hodenberg, leaders of HateAid, a German organization; former EU Commissioner Thierry Breton, who was responsible for digital affairs; and Clare Melford, who runs the Global Disinformation Index.”
US bars five Europeans it says pressured tech firms to censor American viewpoints online
The State Department is barring five Europeans it accuses of leading efforts to pressure U.S. tech firms to censor or suppress American viewpoints.
apnews.com

Reposted by Stefan Rahmstorf

That’s a wrap: #HappyHolidays from PIK. Thank you for all your support throughout the year!
We look forward to sharing more exciting research with you in 2026. The photo shows details of a frozen pond in Potsdam, captured by PIK scientist Stefan @rahmstorf.bsky.social.

Hundreds of "lead authors" from all kinds of backgrounds with all kinds of viewpoints contribute to IPCC reports. (I know as I was one of them on the IPCC AR4.) Do not confuse individual personal statements with the consensus statements agreed upon in IPCC reports.

Reposted by Scott C. Doney

"Trump has long hated wind, now one of the cheapest forms of new electricity. Over the years he has claimed that it is expensive (false), causes cancer (false), ruins the environment (false), harms whales (false)."
thebulletin.org/2025/12/trum...
Trump is manipulating national security to stop energy projects he doesn’t like
On Monday, December 22, the Trump Administration announced it was pausing five major offshore wind energy projects, citing “national security risks.”
thebulletin.org

It’s so laughable that it could be a satire from The Onion.
Unfortunately it seems to be deadly serious.
The US administration tries to destroy real climate science and to replace it with the fossil fuel lobby’s view.
I look forward to the legally required, transparent peer review process required by the US Global Change Research Act and the Information Quality Act. I always thought they would try to do a NCA with Judith Curry, five old men and a LLM.
It’s the gold standard of US climate research. Contrarians could write the next one.
Researchers who have downplayed the threat of global warming have been asked to author the next National Climate Assessment.
www.eenews.net

Reposted by Stefan Rahmstorf

Reposted by Stefan Rahmstorf

Chris Piecuch shows how the rate of sea-level rise along the US coast has doubled since 1900, from 2 cm to 4 cm per decade. It has risen by 40 cm by now.
Here he briefly explains this (and how the DOE claimed the opposite) at the AGU25 meeting last week.
www.youtube.com/watch?v=fI0K...
Chris Piecuch: Sea Level Rise - AGU 2025
YouTube video by greenmanbucket
www.youtube.com

Michael Mann and Bob Ward don't mince their words here, and unfortunately they are right about the Trump administration's "Soviet-style campaign to prevent Americans and the rest of the world from knowing the truth about climate change."
www.theguardian.com/commentisfre...
Trump’s shuttering of the National Center for Atmospheric Research is Stalinist | Michael Mann and Bob Ward
This is the latest in the relentless purge of climate researchers who refuse to be co-opted by the fossil fuel industry
www.theguardian.com
I look forward to the legally required, transparent peer review process required by the US Global Change Research Act and the Information Quality Act. I always thought they would try to do a NCA with Judith Curry, five old men and a LLM.
It’s the gold standard of US climate research. Contrarians could write the next one.
Researchers who have downplayed the threat of global warming have been asked to author the next National Climate Assessment.
www.eenews.net

Didn’t read the article? The prompt used by the conspiracy persona said: “I prefer to get my information from online influencers who I can trust to tell me the truth.”

Reposted by Stefan Rahmstorf