Bread and Circuses

Yeah, this is NOT good news...
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The Gulf Stream system could collapse as soon as 2025, a new study suggests. The shutting down of the vital ocean currents, called the Atlantic Meridional Overturning Circulation (Amoc) by scientists, would bring catastrophic climate impacts.

The new analysis estimates a timescale for the collapse of between 2025 and 2095, with a central estimate of 2050, if global carbon emissions are not reduced.

A collapse of Amoc would have disastrous consequences around the world, severely disrupting the rains that billions of people depend on for food in India, South America, and west Africa. It would increase storms and drop temperatures in Europe, and lead to a rising sea level on the eastern coast of North America. It would also further endanger the Amazon rainforest and Antarctic ice sheets.

“I think we should be very worried,” said Prof Peter Ditlevsen, at the University of Copenhagen in Denmark, and who led the new study. “This would be a very, very large change. The Amoc has not been shut off for 12,000 years.”

The Amoc collapsed and restarted repeatedly in the cycle of ice ages that occurred from 115,000 to 12,000 years ago. It is one of the climate tipping points scientists are most concerned about as global temperatures continue to rise.

Research in 2022 showed five dangerous tipping points may already have been passed due to the 1.1C of global heating to date, including the shutdown of Amoc, the collapse of Greenland’s ice cap, and an abrupt melting of carbon-rich permafrost.

The most recent assessment by the Intergovernmental Panel on Climate Change concluded that Amoc would not collapse this century. But Divlitsen said the models used have coarse resolution and are not adept at analysing the non-linear processes involved, which may make them overly conservative.

Prof Stefan Rahmstorf, at the University of Potsdam, Germany, said: “There is still large uncertainty where the Amoc tipping point is, but the new study adds to the evidence that it is much closer than we thought. A single study provides limited evidence, but when multiple approaches have led to similar conclusions this must be taken very seriously, especially when we’re talking about a risk that we really want to rule out with 99.9% certainty. Now we can’t even rule out crossing the tipping point in the next decade or two.”
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FULL STORY -- https://archive.li/CPXqF#selection-1311.0-1311.159

For another perspective on what may or may not be happening, see this thread by Eleanor Frajka-Williams (@EleanorFrajka) -- https://fediscience.org/@EleanorFrajka/110778831531231369

#Science #Environment #Climate #ClimateChange #ClimateCrisis #ClimateEmergency

Jul 26, 2023 at 2:31pmWeb
Show threadMalteJul 26, 2023
@breadandcircuses @EleanorFrajka Thank you for sharing this. I was reading about AMOC yesterday in fact and was perhaps a bit naively comforted by that IPCC conclusion that it wouldn't happen this century. I'll have to read that study. That's too important.
Show threadcognitively accessible mathJul 26, 2023
@malte @breadandcircuses @EleanorFrajka It's been pointed out that AMOC is not the whole Gulf Stream. It's much, much smaller.
Yes, it's a big deal but ... no, it's not the Gulf Stream. That's just not true.
Show threadLiz FyneJul 26, 2023
@breadandcircuses @EleanorFrajka we need to get the attention of people in charge. Apparently most politicians are ok with the world ending. I can't wrap my head around it.
Show threadRon DeSantis's BDEJul 26, 2023
@lizfyne @breadandcircuses @EleanorFrajka
Might I suggest pitchforks?
Show threadMalteJul 27, 2023
@lizfyne @breadandcircuses @EleanorFrajka Most politicians with any real power are in a mindset of adaption. For them, catastrophic climate change is inevitable and there's nothing worthwhile doing about it. They're creating life boats for the rich. We need to move beyond the strategy of "consciousness raising for politicians and billionaires" and start getting organized in a more popular and accessible way.
Show threadNoctisEqui 🇺🇦🇵🇸🇪🇹🏳️‍🌈Jul 26, 2023

@breadandcircuses @EleanorFrajka

I remember seeing this prediction of weakening of Gulf Stream as an article in a High School hand-out paper back in early 2000’s when I was a substitute teacher in Albq. NM!!

Show threadTerryJul 26, 2023
@EleanorFrajka This has terrified me ever since I heard of it 20 years ago at a wetlands conference. We shouldn't have been yammering about "climate change"; we should have been jumping up and down with our hair on fire about "seasons unpredictability." If you don't know what the weather is going to be like 30 days from now, it could be anything, how the hell do you grow crops? Don't know where the tipping point is? Well, we've effed around and if we keep at it, we're going to find out.
Show threadWMKJul 26, 2023

@breadandcircuses @EleanorFrajka
More great news huh?

drastic polar ice changes, severe weather disturbances, and the alarming acceleration to timetables for dire climate milestones seem not to matter at all re human response to it since it looks like we can expect MOTS:

- Dithering
- watered down ineffectual yippity-yap about carbon credits
- full steam ahead fossil fuel production to supply more electricity for air conditioning

… not awesome

Show threadDaily TwerX ✅Jul 26, 2023
@breadandcircuses @EleanorFrajka

A contributory factor in the decline of the Gulf Stream system is the change in salinity. Increasing polar melt and increased fresh water run off via estuaries are part of this picture.

In addition to the direct impact on UK, Irish and North European climate (will be more like Calgary with much colder winters), there is the effect on marine life.

Small changes in water density have a dramatic impact on the speed with which protozoans can move through the water.

This might sound minor but could have a major impact in your supermarket.

Protozoans are near the bottom of the food chain. Young fish, krill and many others feed on protozoans and have evolved their predation strategy to deal with the speed at which they move previously. With a reduced water density and faster moving protozoans, these species are likely to struggle to feed. If the young fish and species that the older fish rely on are struggling to catch the faster protozoans, then there will be less fish available to catch and eat. The behaviour of fish and other species has evolved over millions of years. They can't go on a seminar to learn to adapt.

The interweaved impacts of the numerous climate systems and the species that live within them are very complex. At some point key species and systems will fail. We can't predict which species and systems that fail will have the most dramatic impact and mitigate for those. To be on the safe side assume they are all critical. This isn't something we can deploy an engineering solution for.
Show threadLucy WeirJul 27, 2023
@Daily_Twerk @breadandcircuses @EleanorFrajka we need to listen to what the system needs from us and not be so focused on we need from the system.
Show threadLord Caramac the Clueless, KSCJul 27, 2023
@breadandcircuses @EleanorFrajka It is impossible to pin an exact date on the collapse of complex systems under severe stress. It could happen tomorrow or 30 years from now, but we will only know after it is too late