AMOC 2025 this is a big climate issue

The mean of the bootstrapped estimates of the tipping time is 〈t c〉 = 2050, and the 95% confidence interval is 2025–2095.

https://www.nature.com/articles/s41467-023-39810-w

My comments the last AMOC process 12k years ago happened quickly in a four year period.

The AMOC is a major trauma to the gulf stream and the circulation of waters in the Atlantic.

Side note I think the Europeans issuing visas for entry will cut air flights to Europe dramatically. I think the design to head off global warming.

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This is the confidence of one paper from one analysis technique. They might be right, or maybe not. Stefan Rahmstorf has a summary at realclimate.org and concludes:

Timing of the critical AMOC transition is still highly uncertain, but increasingly the evidence points to the risk being far greater than 10 % during this century – even rather worrying for the next few decades. The conservative IPCC estimate, based on climate models which are too stable and don’t get the full freshwater forcing, is in my view outdated now.

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Deja vu all over again. We did this thread topic just two weeks ago. Where is our institutional memory?

From the CNN article on the paper:
“Scientists uninvolved with this study told CNN the exact tipping point for the critical system is uncertain, and that measurements of the currents have so far showed little trend or change.

And speaking of little trend, Fraser and Cunningham reconstructed the AMOC (Atlantic Meridional Overturning Circulation) back to 1900. Looking at their Figure 3, it can be seen that the current strength is now where it was in 1910 and stronger than it was in 1900 and 1970.

120 Years of AMOC Variability Reconstructed From Observations Using the Bernoulli Inverse
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2021GL093893

DB2

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Bob,

There is no point in cherry picking things to make a denial.

We all know you will do that to muddy the waters.

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Referencing 120+ years of AMOC history is hardly ‘cherry picking’.

DB2

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The authors are clear that their method has large uncertainties and explicitly say the work is not evidence against a weakening AMOC:

Thus, although our results do not resolve AMOC weakening over the last century, they should not be interpreted as evidence to the contrary.

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So, no resolution on the condition of the AMOC. Certainly not ‘settled science’. The current has large interdecadal variability.

Jackson et al. found that “the observed decrease in the overturning circulation is consistent with a recovery following a previous increase.”
https://www.nature.com/articles/ngeo2715
DB2

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Here’s what we know:

  • The AMOC has large variability.
  • The AMOC has a tipping point.
  • In the distant past, the AMOC crossed the tipping point, causing large climate changes.
  • Predicting the exact location of tipping points, in climate and pretty much every field of science, is very hard and is the subject of intense research.
  • Human caused climate change is pushing us closer to the tipping point, but we don’t know how far away we still are.
  • Large, rapid changes in the AMOC are a serious risk but not a certainty.

In the words of the famous philosopher, Harry Callahan,

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Clearly, you shot 6 bullets. I’m not worried. :rofl:

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IIRC, that was due to the sudden emptying of an enormous glacial lake in Canada, Lake Agassiz, larger than the Black Sea. I don’t see anything like that at present.

DB2

You fill your bushel of cherries faster than any of us.

I can not see 400 pbb CO2 either…quite literally can not see it. But it is bigger than a glacial lake in Canada.

According to Wikipedia, the Black Sea has 547,000 cubic km of water. The Greenland ice sheet has about 3,000,000 cubic km of ice. That’s about 8% of the global supply of fresh water.

Does that make it more plausible?

Greenland’s average annual melt from 2017 to 2020 was 20% more a year than at the beginning of the decade and more than seven times higher than its annual shrinkage in the early 1990s.
'Devastating' melt of Greenland, Antarctic ice sheets found | AP News

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