A 4500-year reconstruction of sea surface temperature variability at decadal time-scales off North Iceland
By Paul Homewood
Sometimes I get old scientific papers emailed to me. This one is from 2008, but I have not come across it before, and it is still highly relevant:
Below is the key finding:
There has been a marked decline in SSTs since the MWP, with them dropping to the lowest in the 4500 year series.
It should be pointed out that this particular core is expressed as years before 1950.
Another core gives more recent data, clearly showing the Great Salinity Anomaly (GSA) in the 1960s, which marked the shift to a drastically colder climate in Iceland at the time:
Although this study only looks at one small area off the North Iceland coast, it is one which is important in understanding Arctic climate, as it a place where various major ocean currents interact. It is therefore instrumental in the advance or retreat of the polar front.
These findings support conclusions from many other sources. that the Arctic climate is not unusually warm now, indeed by historical standards it is colder than normal. Our perception is skewed because we are viewing it through the lens of the Little Ice Age.
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NOT A LOT OF PEOPLE KNOW THAT 
Now ‘experts’ are claiming the AMOC is slowing and, you guessed it, this could be ‘bad for the climate’.
As for why the AMOC is slowing, global warming may be to blame
https://phys.org/news/2022-11-experts-ocean-currents.html
So yet another circular argument. It fits.
Given the massively greater thermal capacity of large bodies of water in comparison with air has anyone conjectured that variations in the AMOC might affect the Global temperature, rather than the other way about?
Are they putting the cart before the horse – again?
Ah, but it’s all our fault, right?
An earlier study found ‘natural variations are still dominant’…but then claims that ‘Improved observation systems could help detect human influences on the current system at an early stage.’
The threshold between natural Atlantic current system fluctuations and a climate change-driven evolution
APRIL 29, 2022
According to the researchers, part of the North Atlantic is cooling—a striking contrast to the majority of ocean regions. All evaluations indicate that since the beginning of the 20th century, natural fluctuations have been the primary reason for this cooling. Nonetheless, the studies indicate that the AMOC has started to slow down in recent decades.
https://phys.org/news/2022-04-threshold-natural-atlantic-current-fluctuations.html
– – –
So human-caused warming of the air is supposedly the problem, but the AMOC slowdown has occurred during natural cooling of the ocean. Figure that one out.
During the MWP, ships sailed through ice-free waters all the way round from Northern Russia to the Pacific – Documented historical fact. However, with the onset of the Little Ice Age, this trading route was shut off for most of the year.
The failure of so called climate modellers to take account of documentary climate evidence or, explain it, shows that their models do not contain the correct variables and therefore cannot predict the future with any acceptable accuracy. The crude ‘eigenfactor’ steady state basis used in computer modelling can predict the situation at an epoch but its extrapolation towards valid time series using summation, has little basis in physical fact. It can predict some futures within a range, but without better physics, it must diverge from reality.
The AMO Index chart seems to correlate well with the global cooling up until 1975 as well as the following warming until the 1997-98 ENSO…and with the “hiatus” since then. None of which correlates with AGW CO2.
The rate of warming at 1000 BP into the MWP looks to be…..”unprecedented”?
As does the cooling out of the MWP about 600 years BP. It looks to have been “downhill” ever since then into the LIA.
Sicre Yiou et al speculate that the northern Icelandic waters SST series obtained from alkenone proxies ‘ reflect changes of the Meridional Overturning Circulation induced by increased ENSO activity ” .. The black diamonds studding the 4500 SST reconstruction signify tephra [ volcanic ash ] deposits . and they do not strike me as a comprehensive dataset as volcanic ash may be a regional marker contingent on air currents whereas sulfate is more widely dispersed in the atmosphere
..Understand they are tephra – not sulfate signposts – and the eruption circa 1362 could not have precipitated the abrupt temperature plunge as the deuterium based good resolution North Atlantic SST reconstruction shows a steep North Atlantic SST downturn and discernably ‘altered character ” commencing in the 1320’s and recurring 1333 – 1336. The 1320’s event just so happens to coincide with the latter stage of the European ‘Great Famine ” the start of temperature reductions observable in the [ Scandinavian ] Fennoscandian pine series – and a merged 13 site European oak chronology. This underscores the fraught nature of highlighting a two location oceanic proxy study although the NA SST 1320’s event corresponds well with the sharp temperature decline visible in the northern Iceland SST series above However It must be said this reconstruction does not corroborate the Greenland temperature reconstructions such as the Alley / Kobashi series which accurately show the Roman and Minoan Optimums as substantially warmer than the MWP – and resurgent warming after 1870 – whereas the alkenone proxy graph reveals a disparate temperature variation trendline with the Homeric Dark Age cold period [ circa 800 BC] implausibly warmer than the [ 1300 BC ] Minoan Optimum
That drop in salinity coincides with the “Sea Ice Years” for Iceland?
You really need to stop adding to the hundreds of papers that clearly show r the MWP was 2 deg hotter than 1959, or there even was such a thing. It makes it very difficult and rather overtly false on the facts for the IPCC to claim there was no natural change for the 2Ka up to 1850 and so all change now is human caused. Not natural. Wrong in the facts of observation. Again. But they keep doing it. Very strange behaviour.
Brian the northern Iceland ocean core series shows the MWP and the Homeric Dark Age cooling phase [ 800 – 700 BC ] warmer than the middle Roman Optimum 2000 – 1800 BP and the 1450 – 1250 BP Minoan Optimum …..This is a dissonant peak and trough time series to the Greenland temperature reconstructions …..Wrong in the facts indeed
Brian:
Not strange at all The IPCC is in the business of lying in its teeth; as it is Communist inspired with Mantra of: “The End Justifies the Means”
No it isn’t “dissonant”. Its regional so varies according to global regional climate effects. But it shows the ne general cycles as variously seen around the World, and their rate , range and periods. These have also been well defined in the periodic power spectrum by Ludecke and Weiss, and others, very probably as the signature cycles of the cyclically b varying solar winds, not insolation. AS measured by Cosmogenic isotopes, a unique proxy from Super Nova cosmic ray fluxes from all over the Universe that the solar winds vary by the interaction of their charged proton fluxes with the higher energy but less intense comic ray fluxes. (Sol is much more proximal but its Proton particle radiation is of much lower energy than super nova events. (Only cosmic rays produce C-14 and Be-10 we can measure the formation rate of against time). Simple basic physics, proven by the observation of nature..
Here are 43 papers on the MWP, in the NH and SH:
http://pages.science-skeptical.de/MWP/MedievalWarmPeriod.htmx
CLick on the specifics for details of reference and enlargement
Here are twenty more from my collection:
https://www.dropbox.com/s/xffozx2nfpy3sia/Interglacial%20climate%20papers.zip?dl=0
Also well seen in the last 4 interglacials, throughout the dominant cycles.
..Brian , are the MWP and Homeric Dark Age cooling period warmer than the Minoan and Roman Optimums in the ‘regional ‘ Greenland time series or indeed any northern hemisphere Holocene temperature reconstructions ?
I would hope you are not ‘Gish Galloping ‘ with that surfeit of temperature data
Can anyone answer the question ?
The winter only NAO index is highly misleading, it makes it appear that negative NAO is associated with a colder AMO & Arctic, but the reverse is true, positive NAO drives a colder AMO & Arctic. Why do they neglect the other seasons? negative NAO in summers 2007 and 2012 resulted in strong Arctic warming and the largest losses of sea ice.
Thanks for sharing that interesting article.
Here is another good paper. There really were no glaciers in Iceland prior to about 5kya.
“The onset of neoglaciation in Iceland and the 4.2 ka event”
https://cp.copernicus.org/articles/15/25/2019/