Cooler Atlantic

[boyblue]

Good luck to all, I'm checking out of netweather due to the climate change groupthink  & the associated sanction ( i.e - posts deleted ) should I dare to question same.

[lorenzo]

Good luck to all, I'm checking out of netweather due to the climate change groupthink  & the associated sanction ( i.e - posts deleted ) should I dare to question same.

 

Sorry to read that boyblue, I deleted several posts to avoid the continuing need to edit and moderate the thread, nothing more. Indeed this edit of the thread was supported by a report from another user who wished the thread not to drift (no pun intended) off at a tangent.

 

There is an entire climate forum located here  https://forum.netweather.tv/forum/105-climate-change-the-science/

 

I would like to re-affirm that posts are not sanctioned, nor is there a 'groupthink' or moderating agenda within the team and there are some discussions more suited to other areas of the forum.

 

Please continue to report posts using the button on each post or PM the forum team. Thanks.

Edited September 28, 2015 by lorenzo

[Methuselah]

Good luck to all, I'm checking out of netweather due to the climate change groupthink  & the associated sanction ( i.e - posts deleted ) should I dare to question same.

You only need post in the relevant section, boyblue?

[boyblue]

Thanks Lorenzo, I appreciate your comments & don't doubt the overall sincerity of this site.

 

Adios.

[Hocus Pocus]

I think the main problem lies with Mann's past history, that's not to say the article isn't correct but I still think that we're overlooking the big white elephant in the room the AMO and it doing what's it's always done.

[knocker]

I think the main problem lies with Mann's past history, that's not to say the article isn't correct but I still think that we're overlooking the big white elephant in the room the AMO and it doing what's it's always done.

 

Would you elaborate on that?

Edited September 28, 2015 by knocker

[Roger J Smith]

My theoretical bias is that ocean temperatures do not directly cause weather patterns so much as they inevitably interact with them after they get forced from a different set of causal factors. The problem for testing this cause and effect coupling is that sometimes it is difficult to separate out whether (a) the pattern you see is caused from the ocean temperature pattern below it, (b) the ocean temperature pattern is caused by the atmospheric pattern above it, or © some other causes produce each of them either as a couplet or independently then they have to interact with each other.

 

So this tends to influence any given researcher's perception of how the cold pool in the Atlantic will affect the coming winter synoptic patterns. One theory would say, effects might be minimal because even at 4-5 deg below normal by midwinter these water temps will not be colder than air mass temps over the same region anyway, so all that will change is that the surface instability normally caused by ocean heating of the boundary layer will disappear. Another theory might say that the colder waters will inevitably force the jet stream to diverge or to remain unified but further south than normal in that sector. While that's not a guarantee of colder temperatures, it almost certainly guarantees a stormier pattern in western Europe and perhaps more variable temperature regime.

 

Yet another theory says the colder Atlantic is an easier place for high latitude blocking to develop, especially if coupled with the El Nino and even more so if that El Nino translates west to become a Modoki type El Nino. This appears to favour west Greenland blocking too.

 

I've been looking at all this in detail recently from a very particular research perspective and my conclusion is that the winter is likely to be divided into two halves, the first being a very stormy pattern that remains rather mild much of the time, and the second being dominated by blocking highs and possibly rather extreme cold at times. There may not be a very large analogue set for the coming winter. But I do think we will be seeing major consequences of this cold Atlantic, warm Pacific set up.

 

 

[Midlands Ice Age]

I think the main problem lies with Mann's past history, that's not to say the article isn't correct but I still think that we're overlooking the big white elephant in the room the AMO and it doing what's it's always done.

 

I tend to agree with this. I haven't seen the previous deleted comments, but I thought the following graph produced on the another forum, tends to indicate that the AMO is performing normally.

 

 

 

and furthermore is due a downward spiral.

 

Does the low North Atlantic SST's signal this? Anyones guess.!!

Edited September 28, 2015 by Midlands Ice Age

[seaside 60]

I've held a theory for some time now that the Gulf Stream / North Atlantic Drift has been slowing down or not as strong as it was...nothing excessively scientific except for the huge drop in numbers of European Eels. The adult Eels migrate to the Sargasso Sea to spawn and their offspring hitch a ride on the Gulf Stream and then return to the rivers as Elvers to grow into Eels.

 

I think there's a link to even a slight decline in the strength of the plume of water which they use to travel meaning much lower numbers returning to northern Europe.

 

Just a theory...

To blow that away last year was the best spawning for many years almost a record on the number of elvers that made it back to our shores.

HOwever until last year that was true.

[Hocus Pocus]

Would you elaborate on that?

Not here knocker but the histrionics surrounding Mr Mann are well documented.

Edited September 28, 2015 by Hocus Pocus

[knocker]

Not here knocker but the histrionics surrounding Mr Mann are well documented.

 

I'm aware of the 'histrionics' and the scientific repudiation of the libellous witch hunt which totally exonerated him is also well documented. As far as I'm aware his reputation remains unsullied in scientific circles so if you are still inferring otherwise at least have the balls to say so.

Edited September 28, 2015 by knocker

[Hocus Pocus]

I'm aware of the 'histrionics' and the scientific repudiation of the libellous witch hunt which totally exonerated him is also well documented. As far as I'm aware his reputation remains unsullied in scientific circles so if you are still inferring otherwise at least have the balls to say so.

As I implied earlier this thread isn't the place to discuss such and my opinion on Mann is irrelevant to the topic in hand, which is a cooler Atlantic in case you missed the title of the thread.

I tend to agree with this. I haven't seen the previous deleted comments, but I thought the following graph produced on the another forum, tends to indicate that the AMO is performing normally.

 

 

 

and furthermore is due a downward spiral.

 

Does the low North Atlantic SST's signal this? Anyones guess.!!

Indeed MIA, theres absolutely nothing untoward happening now which hasn't happened with previous AMO cycles.

[BornFromTheVoid]

 

Indeed MIA, theres absolutely nothing untoward happening now which hasn't happened with previous AMO cycles.

 

You keep saying this is all normal, despite evidence to the contrary from both published studies and re-analysis data.

 

Can you provide some evidence that a persistent cold patch in the north Atlantic is a precursor to a shift in AMO phase?

[knocker]

As I implied earlier this thread isn't the place to discuss such and my opinion on Mann is irrelevant to the topic in hand, which is a cooler Atlantic in case you missed the title of the thread.

 

 

So why choose to post an irrelevant opinion in the first place if it wasn't to make a point. It is you who seems to have mislaid the title of the thread.

Edited September 28, 2015 by knocker

[Midlands Ice Age]

You keep saying this is all normal, despite evidence to the contrary from both published studies and re-analysis data.

 

Can you provide some evidence that a persistent cold patch in the north Atlantic is a precursor to a shift in AMO phase?

 

No. but can you prove its not?.. To me its not coincidental that we are due a switch in the AMO, and low and behold here comes a massive pool of cold water. Perhaps it is a total coincidence!!

 

 

Lets see how it develops further into the cycle before we speculate too much.

 

MIA

Edited September 28, 2015 by Midlands Ice Age

[Cheshire Freeze]

I've been looking at all this in detail recently from a very particular research perspective and my conclusion is that the winter is likely to be divided into two halves, the first being a very stormy pattern that remains rather mild much of the time, and the second being dominated by blocking highs and possibly rather extreme cold at times. There may not be a very large analogue set for the coming winter. But I do think we will be seeing major consequences of this cold Atlantic, warm Pacific set up.

 

I would expect that there could be some spectacular ramifications on the UK weather this winter, whether that be for colder or for warmer. Can't help thinking we may see some extremes this year....

[BornFromTheVoid]

No. but can you prove its not?.. To me its not coincidental that we are due a switch in the AMO, and low and behold here comes a massive pool of cold water. Perhaps it is a total coincidence!!

 

 

Lets see how it develops further into the cycle before we speculate too much.

 

MIA

 

Are you really asking me to prove a negative? Really?

Edited September 28, 2015 by BornFromTheVoid

[Gael_Force]

Are you really asking me to prove a negative? Really?

How far back does the surface skin temperature reanalysis go? You did one for '72 a few pages ago; is it possible to post the link for that site and maybe someone could look at SSTA just prior to the shifts in MIA's graph.

 

Just to add - it strikes me they may have a point about cold pools before or just at the turn to cold phase. Your chart for 72 and Lorenzo's graph with '74 as record cold.

Edited September 28, 2015 by Gael_Force

[BornFromTheVoid]

How far back does the surface skin temperature reanalysis go? You did one for '72 a few pages ago; is it possible to post the link for that site and maybe someone could look at SSTA just prior to the shifts in MIA's graph.

 

Just to add - it strikes me they may have a point about cold pools before or just at the turn to cold phase. Your chart for 72 and Lorenzo's graph with '74 as record cold.

 

I don't even disagree with the idea that it may be related to the AMO, just looking for those that are convinced it's the AMO to provide some evidence!

 

I'll try get together some AMO data going back as far as I can (current spreadsheet is only to '48) and try use the Kaplan SST data which goes back into the 19th century. Shall get some graphs up first thing tomorrow!

[Blessed Weather]

I think the main problem lies with Mann's past history, that's not to say the article isn't correct but I still think that we're overlooking the big white elephant in the room the AMO and it doing what's it's always done.

 

 

I tend to agree with this. I haven't seen the previous deleted comments, but I thought the following graph produced on the another forum, tends to indicate that the AMO is performing normally.

 

 

 

and furthermore is due a downward spiral.

 

Does the low North Atlantic SST's signal this? Anyones guess.!!

 

Is the point being missed here?

 

My understanding from reading the various research papers posted in this thread is that the AMO phase is a significant driver of the northern hemisphere climate but phases are NOT driven by the AMOC. Research looking at the past 450 years shows the phases are largely driven by external forcing with volcanic and solar activity being the two main drivers. This research suggests the role of the AMOC is to moderate the impact of the AMO phase. It found a weak AMOC “characterized the Little Ice Ageâ€.

 

(See Post #64 on page 4 by Yarmy and the paper “Evidence for external forcing of the Atlantic Multidecadal Oscillation since termination of the Little Ice Ageâ€. Also my comments in my Post #74).

 

If we then look at the research findings in a paper titled “Exceptional twentieth century slowdown in Atlantic Ocean overturning circulation†published in March 2015, this found that the slowing of the AMOC since the 1970’s “has been unprecedented over the past millennium†due to the levels of meltwater and fresh water run-off entering the N. Atlantic. (See my post #97 on page 5).

 

So yes, your views that the AMO “is performing normally†is likely correct. BUT, it’s the fact that the AMO looks to be entering a negative (cold) phase, whilst at the same time the slowing of the AMOC is “unprecedented over the past millennium†so is less able to moderate the effects of the AMO. This is the fascinating development for me and it will be interesting to see the results of the October 2015 RAPID cruise for an update on the AMOC strength. Interesting times in my view.

[lorenzo]

I got a reply from the Met Office which is good.

 

Thank you for your email.

I can confirm your enquiry has been directed to John Siddorn and other colleagues here at the Met Office.  We aim to issue a full response within 28 working days.

Kind regards,

[lorenzo]

The 13 hours later this arrived..

 

Many thanks for your enquiry regarding North Atlantic sea surface temperatures. I have spoken to the relevant scientists within the Met Office Hadley Centre who have said that the North Atlantic, and particularly the northern part, is a region of the world that varies a lot on time scales of decades. There was a cool period with a pattern similar to the current pattern of SSTs in the 1960s after which it warmed again. The current area of cool SSTs was caused partly by strong winds over the Atlantic during the winter 2013-14 taking a lot of heat out of the ocean, but current understanding is that there are longer term changes going on in the Atlantic that would give a similar temperature pattern. This is discussed in a Met Office report which was recently released entitled ‘Big Changes Underway in the Climate System?’, and can be found on the Met Office web site at the link below The relevant section is entitled ‘A longer term shift in the Atlantic?’, which starts on page 9.

http://www.metoffice.gov.uk/research/news/2015/changes-in-climate-system

 

The magnitude of the changes on time scales of decades is larger than the effects we expect from Greenland land-ice melt or other factors slowing down the Atlantic conveyor belt. Therefore it is likely that the current SST cold anomalies are more due to effects on the interannual and decadal time scales. The measurements we have of the conveyor belt are only ten years long and not at the ideal latitude to study the northern North Atlantic, but it is proposed by some peer reviewed and published research, that the conveyor belt is currently decreasing, largely due to natural climate variability and only a little due to human induced climate change.

 

Some references which can provide further information are below;

 

Hermanson, L., et al (2014), Forecast cooling of the Atlantic subpolar gyre and associated impacts, Geophysical Research Letters, 41, pages 5167-5174, doi:10.1002/2014GLO60420.

 

Knight, J. R., C. K., and A. A. Scaife (2006), Climate impacts of the Atlantic Multidecadal Oscillation, Geophys. Res. Lett., 33, L17706, doi:10.1029/2006GL026242

 

 

 

These are fantastic sources and not had a, the  chance to read through them all yet. suffice to say that the studies delivered from a forecasting perspective do not incude winter, or any predication to Nino, so for this year the above info. is 'read only'

 

I like the efficiency of response the quotes in the article already cited here - circulation energy chart.

 

Ace is a clue, pretty cool links.

[knocker]

Great stuff Lorenzo;  will read tomorrow all being well.

[Midlands Ice Age]

Are you really asking me to prove a negative? Really?

 

Yes,

 

I had written this prior to seeing Lorenzo' post above, so it could be superceded!!!!

 

To me it looks fairly obvious that changes are occuring.

 

Cold pooling  of this size is likely to be exceptional. But does anyone yet really understand why?.

 

.Is it the returning current which is misbehaving or is it just that the AMO is losing its strength due to other factors..  Maybe a combination of both?

 

I do not claim to know. I suspect we will not know until we have more details (RAPID arrays) at both higher latitudes in the North Atlantic and also something looking at what is going on in the South Atlantic.  Here a 500 mile swing of the current coming around the Indian ocean around Cape Town could cause a huge rippling effect up the Atlantic changing both the strengths and directions of the currents into the tropics. Look at Knockers great ocean current charts and just imagine if the currents were pushed up the Central Atlantic, rather than around Africa. 

 

The odds that this is connected with the upcoming switch in the AMO, I would suggest are  large. Whether the changes will be made even more severe due to the salinity effects in the north Atlantic are also probable.  The state of our current knowledge of this latest process has only been primed during the last 1 or maybe 2 years. I think it will take more than a little conjecture to sort it out.

 

The other thing that needs to be thought about is whether or not this is independent or not of the current ENSO pattern.  I would have thought that somewhere there would be a commensurate increase in SST's (unless this is the result of deep water being sent to the surface). If the latter then it would appear that it will result in a fairly substantial cooling effect on the global SST;s, in future years.

 

As I say, I don't pretend to know the answers. It could well be it will all die away in the next couple of months if a highly positive NAO sets up this winter, but if it doesn't,  we sure are in for an interesting period ahead. In my opinion nothing can be ruled out.

 

 

MIA.

Edited September 28, 2015 by Midlands Ice Age

[lorenzo]

One I think the AMO is losing/flipping.

 

Two this is going to be impossible to fathom until around 2075 -2100 due to the impacts of solar on the stratosphere.

 

Limited dataset ( 11 years) only held on the deep THC is insufficient to envelope even a solar cycle analog, let alone solar plus unique ENSO. Data and analog influences therefore new builds and learnings will be created this season.

 

Remember the influence on the forecast is how well the ocean sea parametrization exist in the NWP.

 

Fascinating.