⏰ Reminder: Tomorrow I’ll join @climtip.bsky.social to discuss the future of the AMOC.

Our Nature study suggests collapse is unlikely this century — but the risks remain critical.

🗓️ 2 Sept, 14:00–15:00 CEST
👉 tum-conf.zoom.us/j/6933421034...

We find it’s highly unlikely in today’s climate. But the risk grows as the AMOC nears a tipping point.

🔗 iopscience.iop.org/article/10.1...

But most CMIP6 models underestimate this variability, which may limit how well they capture ENSO & global ocean heat uptake.

🔗 journals.ametsoc.org/view/journal...

1️⃣ Zonal wind stress & Pacific heat uptake:
📄 New Journal of Climate study led by Mike Bell!

We show zonal wind stress explains up to 80% of interannual variability in equatorial Pacific heat uptake (NSHF).

Could Southern Ocean winds sustain the future AMOC—and might Pacific circulation shifts decide its fate? Insights from our recent @nature.com study on AMOC resilience 🌊

Join me tomorrow morning (08:40 — Room 1.34) at #EGU25.

Talk details ➡️ meetingorganizer.copernicus.org/EGU25/EGU25-...

4/ Our study has also received wider media coverage — here’s a snapshot of the headlines.
Thanks to all the journalists helping bring attention to AMOC and its role in the climate system.

3/ Thanks to the journalists and editors from the science magazines and media outlets who helped highlight our work.
Links to science magazine articles: tinyurl.com/yc3pzned

🧵🌊 It’s been a month since our AMOC study came out. Stefan Rahmstorf questioned why the media framed it as showing “less severe” outcomes.

The framing wasn’t off—it reflected the broader context. Here’s why the headlines were pretty accurate.

📄 www.nature.com/articles/s41...

3/ By balancing Southern Ocean upwelling, the PMOC may have enabled past AMOC collapses. A closed Bering Strait could have strengthened it—but past climates had many other factors at play: different base state climates, ice sheet size, and shifting Southern Ocean winds 🌍

2/ 🔍 Evidence of a PMOC during the Last Glacial Period & Pliocene suggests it may have played a role in past AMOC weakening or collapses.

8/ 🔍 Our study reveals a key knowledge gap: the Pacific circulation influences the AMOC more than we thought.

Changes in the Pacific could disrupt marine ecosystems 🐟, alter carbon storage, and trigger unexpected climate shifts 🌎

There’s still so much to uncover❗️

6/ Models reveal further resilience: Even under extreme climate change 🌡️, the PMOC doesn’t get strong enough to trigger a total AMOC shutdown by 2100—and it’s absent under realistic scenarios.

5/ Enter the Pacific overturning circulation (PMOC). When the PMOC strengthens 🔁, it increases water sinking in the Pacific ⬇️, helping to balance water rising in the Southern Ocean ⬆️—this weakens the AMOC. The twist?

4/ 💨 Southern Ocean winds work like a powerful pump, pulling deep waters to the surface. This upwelling keeps the AMOC running as the planet warms 🌍—and models show these winds will only strengthen. But that’s not the full story…

3/ 🚨 One recent study warns the AMOC could collapse as soon as 2025; others predict later this century.

However, CMIP6 climate models show persistent Southern Ocean winds prevent a total collapse—even under extreme climate change scenarios 🌡️. Here’s how 👇

2/ What is AMOC (Atlantic overturning circulation)? Think of it as an ocean conveyor belt 🔁, moving warm waters north 🔥 and cold waters south ❄️

Its collapse could trigger freezing European winters, devastating weather shifts, and accelerated sea level rise.

🌊 Today in @nature.com: Is the AMOC on the brink of collapse?

Unlikely before 2100—but the risks are real 🚨

We find Southern Ocean winds keep this vital ocean "heat engine" running, even under extreme #climatechange. But the Pacific holds a surprise…

tinyurl.com/yt6u4e7d
Let’s explore 🧪👇

1/ This is incorrect (an easy mistake), else it would indeed be very worrying. ORAS5 reanalysis overestimates AMOC strength before 2000 (~30Sv) and thus shows an exaggerated weakening. My figure on subpolar North Atlantic AMOC strength highlights this issue. Details below 👇