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jai mitchell

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Beaufort Gyre Reversal and a Return to 1960's Level SIE
« on: December 13, 2017, 05:18:30 PM »
This interesting presentation about the potential for a long-term reversal of the Beaufort Gyre under a warming Arctic is very provocative.  While being unable to hear the actual presentation that these slides are associated with (link: https://www.us-ocb.org/wp-content/uploads/sites/43/2017/03/OCB-meeting-2014-Beaufort_Gyre_Dynamics_and_implications_for_North_Atlantic-Arctic-exchange-1_189964.pdf ) the image below is almost magical in its projections. 

Fuller discussion of this can be found here.  http://e360.yale.edu/features/how-a-wayward-arctic-current-could-cool-the-climate-in-europe

Wouldn't that be wonderful???
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AbruptSLR

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #1 on: December 13, 2017, 07:31:40 PM »
jai,

Since your linked PowerPoint presentation was release in 2014, the Beaufort Gyre (BG) has continued to accumulate a greater volume of freshwater, and if the linked reference is correct, then ice mass loss from the GIS is most likely to blame for this atypically large accumulation of freshwater in the BG.  Furthermore, I suspect that as the Jakobshavn Glacier's grounding line is about to recede down a portion of negative sloping bed, I suspect that until about 2028 ice mass loss from the GIS will be sufficient to keep the BG accumulating more and more freshwater.  This makes me concerned that when the BG eventually reverses its rotation after 2028, the freshwater hosing of the North Atlantic will induce a temporary slowing of the AMOC; which due to bipolar seesaw could trigger the WAIS to begin its main phase of collapse by 2040.

Best,
ASLR

Andrey Proshutinsky, Dmitry Dukhovskoy, Mary-Louise Timmermans, Richard Krishfield, Jonathan L. Bamber (2015), "Arctic circulation regimes", Philosophical Transactions of the Royal Society A, DOI: 10.1098/rsta.2014.0160

http://rsta.royalsocietypublishing.org/content/373/2052/20140160

Abstract: "Between 1948 and 1996, mean annual environmental parameters in the Arctic experienced a well-pronounced decadal variability with two basic circulation patterns: cyclonic and anticyclonic alternating at 5 to 7 year intervals. During cyclonic regimes, low sea-level atmospheric pressure (SLP) dominated over the Arctic Ocean driving sea ice and the upper ocean counterclockwise; the Arctic atmosphere was relatively warm and humid, and freshwater flux from the Arctic Ocean towards the subarctic seas was intensified. By contrast, during anticylonic circulation regimes, high SLP dominated driving sea ice and the upper ocean clockwise. Meanwhile, the atmosphere was cold and dry and the freshwater flux from the Arctic to the subarctic seas was reduced. Since 1997, however, the Arctic system has been under the influence of an anticyclonic circulation regime (17 years) with a set of environmental parameters that are atypical for this regime. We discuss a hypothesis explaining the causes and mechanisms regulating the intensity and duration of Arctic circulation regimes, and speculate how changes in freshwater fluxes from the Arctic Ocean and Greenland impact environmental conditions and interrupt their decadal variability."
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jai mitchell

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #2 on: December 13, 2017, 07:46:43 PM »
With regard to the "arctic cooling of the 1970's' in your last graphic, I suggest the following correction (not that it was your error).

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AbruptSLR

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #3 on: December 13, 2017, 08:05:16 PM »
With regard to the "arctic cooling of the 1970's' in your last graphic, I suggest the following correction (not that it was your error).

jai,

I think that the graphic that you cite is indicating changes in surface salinity of the North Atlantic (due to freshwater hosing from the Beaufort Gyre), not changes in SAT for the Arctic.

Best,
ASLR
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Pmt111500

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #4 on: December 13, 2017, 09:14:14 PM »
Looks like one which could be published on Apr-1st.
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AbruptSLR

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #5 on: December 13, 2017, 09:31:55 PM »
Looks like one which could be published on Apr-1st.

The increasing freshwater accumulation with the Beaufort Gyre, BG, is all too real (& is measurable as indicated by the linked report), and that accumulation of freshwater will advect to the North Atlantic sooner, or later:

https://www.polartrec.com/expeditions/co2-and-ph-studies-of-the-arctic-ocean/journals/2017-10-01

Extract: "During the rapid increase in BG freshwater content over 2005-2007 sea-ice meltwater increased by 2.7 m in the central BG region and low-salinity water from the Mackenzie River was advected to the southern BG region. After 2007 the major contributors to the freshwater increase of the BG freshwater reservoir have been Mackenzie river, fresh water from the Pacific Ocean, and from ice melt and precipitation minus evaporation."
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Neven

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #6 on: December 13, 2017, 09:39:00 PM »
Wouldn't that be wonderful???

It would be wonderful if at the same time the world stopped warming, or at least CO2 concentrations would be going down. But such a huge change, while at the same time the entire system sucks up more and more energy, almost guarantees unforeseen consequences to go with it.

I had already had a tab open with that Yale E360 article, and your opening this thread spurred me to read it. Right away after reading the opening sentence...

Quote
For millennia, the Beaufort Gyre — a massive wind-driven current in the Arctic Ocean — has been regulating climate and sea ice formation at the top of the world.

I'm like: And what is driving these winds that are driving the Beaufort Gyre, and isn't this the thing that is actually regulating the mentioned stuff? 'For years my steering wheel has brought me to places I needed to go'.  ;)

But there's something else I don't get. In the article it says:

Quote
During the second half of the 20th century — and, most likely, earlier — the gyre adhered to a cyclical pattern in which it would shift gears every five to seven years and temporarily spin in a counter-clockwise direction, expelling ice and freshwater into the eastern Arctic Ocean and the North Atlantic. But for more than a dozen years, this carousel of ice and, increasingly, freshwater has been spinning faster in its usual clockwise direction, all the while collecting more and more freshwater from three sources: melting sea ice, huge volumes of runoff flowing into the Arctic Ocean from Russian and North American rivers, and the relatively fresh water streaming in from the Bering Sea.

This suggests that the BG is either turning clockwise or counter-clockwise for long stretches of time. But my perception is that it is constantly switching. Note, however, that I do most of my perceiving during the summer. Maybe this is about autumn and winter. But the article suggests, several times, that the BG is spinning like crazy, but can suddenly reverse. I'm reading the article for the second time now, and it somewhat confuses me.

I'll now go read the presentation you link to, jai.

BTW In the Yale E360 article there is mention and a couple of quotes from Alek Petty. Back in 2016 he wrote a guest blog for the ASIB about the Beaufort Gyre and fresh water. I'm re-reading that too.
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AbruptSLR

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #7 on: December 13, 2017, 11:00:15 PM »
Due to the importance of the coming freshwater flux from the Beaufort Gyre in to the North Atlantic (particularly w.r.t. Hansen's freshwater hosing-climate feedback mechanism), I provide the following selected information about the 2018 Ocean Science Meeting Session entitled: " HE003: Freshwater Fluxes in the Arctic Ocean – North Atlantic Climate System"

https://agu.confex.com/agu/os18/preliminaryview.cgi/Session23525

Summary: "Oceanic and sea ice freshwater fluxes in the Arctic Ocean – North Atlantic climate system impact thermohaline and convective processes, with far-reaching influence on climate. Increased freshwater fluxes to the Arctic Ocean along with the wind-driven anticyclonic circulation have resulted in growing freshwater content in the Beaufort Gyre. There is no observational evidence of significant changes in freshwater fluxes between the Arctic Ocean and the North Atlantic. Yet freshwater flux from the Greenland Ice Sheet is clearly increasing and may be impacting thermohaline processes in the North Atlantic. It is a priority to discern the driving mechanisms, the role and consequences of changing freshwater fluxes into the Arctic Ocean and North Atlantic. This session solicits papers addressing issues related to oceanic freshwater fluxes (liquid and sea ice) in the Arctic Ocean – North Atlantic climate system. Possible topics include: Propagation mechanisms, pathways and time scales of fresh water anomalies; residence time of fresh water; impacts of changes to the cryosphere; the role of freshwater in the future Arctic climate; the sensitivity of thermohaline circulation to freshwater fluxes; the relationship between sea ice and freshwater content in the ocean; and, biological and environmental consequences of increased freshwater fluxes."

Laura de Steur, et al (2018), "Increased freshwater export though Fram Strait contributes to freshening in the North Atlantic (301769)"

Andrey Yu Proshutinsky, Richard A Krishfield, Mary-Louise Timmermans and William James Williams (2018), "Causes and Consequences of Beaufort Gyre Freshwater Content Changes in 2003-2017 (303087)"

Dmitry S Dukhovskoy (2018), "Freshwater pathways in the Arctic Ocean and northern North Atlantic from a numerical experiment with passive tracers (304003)"

Oleg Saenko et al (2018), "Response of the North Atlantic Dynamic Sea Level and Circulation to Greenland Meltwater under Present and Projected Climates (304135)"

Elizabeth Douglass (2018), "Impact of Freshwater from Arctic Rivers in a High-Resolution Model (305887)"

Subrahmanyam Bulusu (2018), "Recent changes in the Arctic Circulation and Freshwater Fluxes (Invited) (306593)"

Freshwater fluxes between the Arctic Ocean and the North Atlantic from water stable isotopes: study of coastal currents and interior of the subpolar gyre. (308866)

A new record of North Atlantic sea surface salinity and temperature from 1896–2015 reveals modes of variability and long–term trends (309308)
Andrew Ronald Friedman1, Gilles P Reverdin2, Myriam Khodri1 and Guillaume Gastineau1, (1)Sorbonne-Universités, LOCEAN, CNRS/IRD/UPMC/MNHN, Paris, France, (2)LOCEAN - Sorbonne Universités - UPMC/CNRS/IRD/MNHN, Paris, France
Marion Benetti et al. (2018), "Observed Greenland Glacial Melt Water Distribution in the Greenland Sea (310757)"

Caroline A Katsman et al (2018), "Impacts of Arctic precipitation changes on the downwelling limb of the Atlantic Meridional Overturning Circulation (310762)

Heather Regan (2018), "Investigating the Spatial and Temporal Variability of the Beaufort Gyre from Satellite Observations (311439)"
 
Cristian Florindo-Lopez  et al (2018), "Observational Evidence of Multi-Decadal Changes in Arctic Freshwater Transport to the Subpolar North Atlantic (313117)"

Nathan Grivault (2018), "Frequency of Volume and Freshwater Events Leaving the Arctic Ocean: A Numerical Study. (314363)"

Gilles Garric (2018), "Dependencies of Arctic Freshwater Content and Transport to Surface Atmospheric Conditions (316214)"

Per Pemberton et al. (2018), "The response of the Arctic Ocean to freshwater and wind perturbations (317179)"

Helen Johnson et al (2018), "Response of Arctic Ocean Freshwater Content to Large Scale Atmospheric Forcing Changes in a Coupled Climate Model  (317606)"

Rory Laiho et al. (2018), "Internal Variability in the Arctic Freshwater Budget as Simulated by the CESM Large Ensemble (321495)"

Clark William Pennelly et al. (2018), "Numerical modeling in the northern Atlantic: Labrador Sea freshwater. (321605)"

Marilena Oltmanns et al (2018), "Rapid North Atlantic Cooling Induced by Fresh, Cold and Shallow Mixed Layers in the Subpolar Gyre (321700)"

Jiayan Yang, (2018), "A process-modeling study of the Arctic-Atlantic Ocean exchanges and their role in the Arctic Ocean freshwater export (322447)"
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AbruptSLR

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #8 on: December 13, 2017, 11:07:14 PM »
I'm like: And what is driving these winds that are driving the Beaufort Gyre, and isn't this the thing that is actually regulating the mentioned stuff? 'For years my steering wheel has brought me to places I needed to go'.  ;)

But there's something else I don't get. In the article it says:

Quote
During the second half of the 20th century — and, most likely, earlier — the gyre adhered to a cyclical pattern in which it would shift gears every five to seven years and temporarily spin in a counter-clockwise direction, expelling ice and freshwater into the eastern Arctic Ocean and the North Atlantic. But for more than a dozen years, this carousel of ice and, increasingly, freshwater has been spinning faster in its usual clockwise direction, all the while collecting more and more freshwater from three sources: melting sea ice, huge volumes of runoff flowing into the Arctic Ocean from Russian and North American rivers, and the relatively fresh water streaming in from the Bering Sea.

This suggests that the BG is either turning clockwise or counter-clockwise for long stretches of time. But my perception is that it is constantly switching. Note, however, that I do most of my perceiving during the summer. Maybe this is about autumn and winter. But the article suggests, several times, that the BG is spinning like crazy, but can suddenly reverse. I'm reading the article for the second time now, and it somewhat confuses me.

One can't just watch the sea ice movement patterns to determine the direction of circulation of the BG as most is its mass is associated with deeper water currents below the surface.
« Last Edit: December 14, 2017, 03:58:32 PM by AbruptSLR »
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Pmt111500

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #9 on: December 14, 2017, 05:06:43 AM »
Hmm, so this would be more about Arctic-North Atlantic -relations? This could be a soft landing back to readinh scientific articles that I've missed in past 6 months (or a year or so, who cares, since the rigged electionä). I too prefer models of static universe rather than some heat death m8dels. Let bifurcation point = now, let bifurcation point-1 = one year before measurements began, predict the future behavior of the function.

But ok, maybe there is something to it ( haven't read it yet ).
« Last Edit: December 14, 2017, 05:59:16 AM by Pmt111500 »
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Bruce Steele

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #10 on: December 14, 2017, 07:08:39 AM »
Since the 2012 GAC I have been watching ITP buoys. They have shown a deepening of fresh water in the Pacific warm water layer yes but when did the BG reverse?  Slow down yes , on occasion, but when did buoys move from the Beaufort off Barrow or the Mackenzie eastward ( counter clockwise) and exit the Arctic via the Fram ? I must have missed something but the ITP buoy data is all cataloged and available for review. Where is the evidence of a reversal ?  Not saying it never happens but damn I must have missed it.
 I would think the Garlic press in 2016 was evidence of a large freshwater exit but it wasn't the Fram
and it wasn't a reversal.

Pmt111500

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #11 on: December 14, 2017, 07:45:16 AM »
The reversals have been quite short in duration, week or two at times. I don't remember if there's been longer durations nor if there's been any seasonality or changes in seasonality. I do remember though, they've not happened every year or at least there's no solid data of these, so maybe they've become more frequent in some datasets.
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AbruptSLR

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #12 on: December 14, 2017, 04:11:46 PM »
If one wants to live in a small enough bubble (of information) then one can come to any conclusion that one is comfortable with.  However, global circulation models, GCMs, cannot yet capture all of the global feedback mechanism of the Earth Systems, so in this post I discuss how a freshwater release from the BG into the North Atlantic can cause Arctic Amplification due to the bipolar seesaw, Agulhas Leakage and atmospheric Rossby waves advecting energy from the tropical ocean directly to the Arctic.

The first linked Marino & Zahn (2015) reference (and first attached image) shows how a cooling of the North Atlantic can cause warming around Antarctica and an increase of Agulhas Leakage which can interact with the AMOC to strengthen Arctic Amplification and the bipolar seesaw:

Gianluca Marino and Rainer Zahn (January 2015), "The Agulhas Leakage: the missing link in the interhemispheric climate seesaw?", Past Global Changes Magazine, SCIENCE HIGHLIGHTS: Glacial terminations and interglacials

http://www.pages-igbp.org/download/docs/magazine/2015-1/PAGESmagazine_2015(1)_22-23_Marino.pdf

&

With continued global warming one can expect more Agulhas leakage (see the second image); which per the second linked reference means that one can expect the AMOC to continue slowing; which should work synergistically with Hansen's ice-climate feedback, particularly if the WAIS collapses in coming decades:

Kathryn A. Kelly, Kyla Drushka, LuAnne Thompson, Dewi Le Bars & Elaine L. McDonagh (25 July 2016), "Impact of slowdown of Atlantic overturning circulation on heat and freshwater transports", Geophysical Research Letters, DOI: 10.1002/2016GL069789

http://onlinelibrary.wiley.com/doi/10.1002/2016GL069789/abstract

And for those who have trouble envisioning how increased Agulhas Leakage triggered by a cooling of the North Atlantic could lead to Arctic Amplification associated with the transfer of energy through the atmosphere from the Tropical Atlantic directly to the Arctic, I provide the third attached image & associate caption from the third linked reference, which show how this occurs due to Rossby Waves:

Merryfield, W. J., F. J. Doblas-Reyes, L. Ferranti, J.-H. Jeong, Y. J. Orsolini, R. I. Saurral, A. A. Scaife, M. A. Tolstykh, and M. Rixen (2017), Advancing climate forecasting, Eos, 98, https://doi.org/10.1029/2017EO086891

https://eos.org/project-updates/advancing-climate-forecasting?utm_source=eos&utm_medium=email&utm_campaign=EosBuzz120117

Caption: "Fig. 1. Averaged atmospheric response during winter in the Northern Hemisphere to recent El Niño events, connecting atmospheric changes in the tropics with those at latitudes farther north and south. Dots represent approximate pathways of planetary waves [after Scaife et al., 2017]. Colors show associated changes in sea level pressure (SLP) in hectopascals (hPa), indicative of atmospheric circulation changes. In the Northern Hemisphere, changes are clockwise for positive contours, represented by warm colors, and counterclockwise for negative contours, represented by cool colors; these directions are opposite in the Southern Hemisphere. Credit: Adam Scaife"
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AbruptSLR

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #13 on: December 14, 2017, 07:46:34 PM »
For those who want further evidence of the bipolar seesaw mechanism, I provide the following linked reference (& associated linked article), that provides details including how atmospheric Rossby wave trains can relatively rapidly activate the bipolar seesaw mechanism (presumably fast enough so that a cooling of the North Atlantic [due a freshwater drainage event from the BG, circa 2030 to 2035] could trigger a main phase collapse of the WAIS by 2040, which would then tip the seesaw in the other direction resulting in increased Artic Amplification:

Turney et al (2017), "Rapid global ocean-atmosphere response to Southern Ocean freshening during the last glacial", Nature Communications, doi:10.1038/s41467-017-00577-6

https://www.nature.com/articles/s41467-017-00577-6

Abstract: "Contrasting Greenland and Antarctic temperatures during the last glacial period (115,000 to 11,650 years ago) are thought to have been driven by imbalances in the rates of formation of North Atlantic and Antarctic Deep Water (the ‘bipolar seesaw’). Here we exploit a bidecadally resolved 14C data set obtained from New Zealand kauri (Agathis australis) to undertake high-precision alignment of key climate data sets spanning iceberg-rafted debris event Heinrich 3 and Greenland Interstadial (GI) 5.1 in the North Atlantic (~30,400 to 28,400 years ago). We observe no divergence between the kauri and Atlantic marine sediment 14C data sets, implying limited changes in deep water formation. However, a Southern Ocean (Atlantic-sector) iceberg rafted debris event appears to have occurred synchronously with GI-5.1 warming and decreased precipitation over the western equatorial Pacific and Atlantic. An ensemble of transient meltwater simulations shows that Antarctic-sourced salinity anomalies can generate climate changes that are propagated globally via an atmospheric Rossby wave train."

&

Title: "How Antarctic ice melt can be a tipping point for the planet's climate"

https://phys.org/news/2017-09-antarctic-ice-planet-climate.html

Extract: "Twenty-five of these major so-called Dansgaard–Oeschger (D-O) warming events have been identified. These abrupt swings in temperature happened too quickly to have been caused by Earth's slowly changing orbit around the Sun. Fascinatingly, when ice cores from Antarctica are compared with those from Greenland, we see a "seesaw" relationship: when it warms in the north, the south cools, and vice versa."
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AbruptSLR

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #14 on: December 15, 2017, 12:16:37 AM »
Agulhas Leakage (see Reply #12) warms the Tropical Atlantic and thus could contribute to the enhanced evaporation in this region, which per the attached image and linked reference, about interglacial periods, can trigger abrupt changes in the AMOC that can lead to warming of the Arctic:

Xu Zhang et al. (2017), "Abrupt North Atlantic circulation changes in response to gradual CO2 forcing in a glacial climate state", Nature Geoscience, doi:10.1038/ngeo2974

http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2974.html

Abstract: "Glacial climate is marked by abrupt, millennial-scale climate changes known as Dansgaard–Oeschger cycles. The most pronounced stadial coolings, Heinrich events, are associated with massive iceberg discharges to the North Atlantic. These events have been linked to variations in the strength of the Atlantic meridional overturning circulation. However, the factors that lead to abrupt transitions between strong and weak circulation regimes remain unclear. Here we show that, in a fully coupled atmosphere–ocean model, gradual changes in atmospheric CO2 concentrations can trigger abrupt climate changes, associated with a regime of bi-stability of the Atlantic meridional overturning circulation under intermediate glacial conditions. We find that changes in atmospheric CO2 concentrations alter the transport of atmospheric moisture across Central America, which modulates the freshwater budget of the North Atlantic and hence deep-water formation. In our simulations, a change in atmospheric CO2 levels of about 15 ppmv—comparable to variations during Dansgaard–Oeschger cycles containing Heinrich events—is sufficient to cause transitions between a weak stadial and a strong interstadial circulation mode. Because changes in the Atlantic meridional overturning circulation are thought to alter atmospheric CO2 levels, we infer that atmospheric CO2 may serve as a negative feedback to transitions between strong and weak circulation modes."

See also the associated linked article entitled: "Scientists throw light on mysterious ice age temperature jumps"

https://phys.org/news/2017-06-scientists-mysterious-ice-age-temperature.html

Extract: "In a new study published today, the researchers show that rising levels of CO2 could have reached a tipping point during these glacial periods, triggering a series of chain events that caused temperatures to rise abruptly.

The findings, which have been published in the journal Nature Geoscience, add to mounting evidence suggesting that gradual changes such as a rising CO2 levels can lead to sudden surprises in our climate, which can be triggered when a certain threshold is crossed.

Previous studies have shown that an essential part of the natural variability of our climate during glacial times is the repeated occurrence of abrupt climate transitions, known as Dansgaard-Oeschger events.

These events are characterized by drastic temperature changes of up to 15°C within a few decades in the high latitudes of the Northern Hemisphere. This was the case during the last glacial period around 100,000 to 20,000 years ago.

It is commonly believed that this was a result of sudden floods of freshwater across the North Atlantic, perhaps as a consequence of melting icebergs.

Co-author of the study Professor Stephen Barker, from Cardiff University's School of Earth and Ocean Sciences, said: "Our results offer an alternative explanation to this phenomenon and show that a gradual rise of CO2 within the atmosphere can hit a tipping point, triggering abrupt temperature shifts that drastically affect the climate across the Northern Hemisphere in a relatively short space of time.

"These findings add to mounting evidence suggesting that there are sweet spots or 'windows of opportunity' within climate space where so-called boundary conditions, such as the level of atmospheric CO2 or the size of continental ice sheets, make abrupt change more likely to occur. Of course, our study looks back in time and the future will be a very different place in terms of ice sheets and CO2 but it remains to be seen whether or not Earth's climate becomes more or less stable as we move forward from here".

Using climate models to understand the physical processes that were at play during the glacial periods, the team were able to show that a gradual rise in CO2 strengthened the trade winds across Central America by inducing an El Nino-like warming pattern with stronger warming in the East Pacific than the Western Atlantic.

As a result there was an increase in moisture transport out of the Atlantic, which effectively increased the salinity and density, of the ocean surfaces, leading to an abrupt increase in circulation strength and temperature rise.

"This does not necessarily mean that a similar response would happen in the future with increasing CO2 levels, since the boundary conditions are different from the ice age," added by Professor Gerrit Lohmann, leader of the Paleoclimate Dynamics group at the Alfred Wegener Institute.

"Nevertheless, our study shows that climate models have the ability of simulating abrupt changes by gradual forcing as seen in paleoclimate data.""
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Bruce Steele

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Re: Beaufort Gyre Reversal and a Return to 1960's Level SIE
« Reply #15 on: July 14, 2019, 10:35:05 PM »
It has been a while since the topic of a gyre reversal has been discussed. Although the Beaufort Gyre used to reverse direction and spin counterclockwise every 5 to 7 years it has now been 21 years since a reversal has occurred. The fresh water in the Gyre has continued to increase as has the Pacific Warm Water in the Beaufort. I was looking for new studies but I didn't find any. The WHOI Beaufort Gyre webpage has a reference to " Arctic Sea Ice Forum "  and ASLR has as good a summary as I can find. 

https://www.whoi.edu/website/beaufortgyre/home

So there is a long range , one week , projection of a strong low pressure setting up over the Gyre. I would think one of these years a reversal will happen . If there was a concurrent Garlic press set-up ...
Anyhow it would be something different than the Arctic we are used to watch melt and freeze.