Those physically realistic models predict subpolar gyre tipping around 2040-2050. This would lead to a local cooling of 1-2 degrees in 10 to 20 years. The Nordic seas would warm, the jet stream shift northward and in summer high pressure over Scandinavia could lead to more (intense) heat waves.

Mechanism: Strengthening of the gyre circulation directly leads to divergence and lower salinity, but on longer timescales it increases salinity due to transport by eddies. An increase in salinity causes convection, changing the density in the water column. This density change strengthens the gyre.

In some climate models abrupt cooling in the subpolar gyre region is found, corresponding to a collapse of convection. Such tipping of the subpolar gyre might already occur around 2040 and could impact the stability of the AMOC.

For an analysis of abrupt shifts see: doi.org/10.1111/nyas...

The subpolar gyre is a wind-driven ocean circulation through the Irminger and Labrador seas. Warm and salty water from the Gulf Stream enters the gyre, where it cools down. This increases the density of the salty waters and leads to convection; the mixing of surface waters with those at depth.

It was a pleasure giving a seminar at the VU today in the Water & Climate Risk group. I enjoyed the great questions and discussion, given me lots of new ideas :)

I discussed subpolar gyre variability mechanisms, links with the AMOC and impacts of an AMOC collapse on European precipitation.

It was a pleasure having such brilliant participants at the 'Introduction to Complex Systems' Summer School @ccss-uu.bsky.social #utrechtsummerschool. This week has flown by and I thoroughly enjoyed seeing them all learn and have fun getting their head around the many #complex phenomena discussed.

And we're off! The 'Introduction to Complex Systems' summer school has started with a great lecture by Ammy Vogtlander: "Uncertainty is the essence of diversity." And it is that diversity we need for resilience. @ccss-uu.bsky.social #utrechtsummerschool #complexity

Enjoyed presenting my poster on the mechanisms of subpolar gyre (SPG) variability in CMIP6 models last week at the #GlobalTippingPointsConference!

Interesting questions, great discussions. I came back even more motivated to improve our understanding of SPG tipping and its impacts.

Great talks and discussions yesterday in the first part of our session on "Forecasting & Governing Tipping Points in the SPG, AMOC and GIS" at the #GTPConference @gsiexeter.bsky.social. We learned about the uncertainty in #AMOCtipping. Looking forward to the second part this afternoon!

Most abrupt shifts are found in the polar regions, but also in the Amazon rainforest and Tibetan plateau. The global warming level at which these shifts occur indicates that there is a substantial risk of abrupt shifts in the subpolar gyre and Barents sea ice already this century.

Amazing day out running the #Klimaatmarathon with my colleagues #IMAU today! Running from the KNMI to Hilversum and back wearing the climate stripes #ShowYourStripes. Great to see so many people out there that care about climate change and want to act.

Last week we got together with a great group of scientists, in Utrecht and online, to discuss everything subpolar gyre. Is it bistable? What are the important variables and mechanisms? How does it link to the AMOC? I'm looking forward to building on the ideas and insights from the workshop.