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Posted
  • Location: Newcastle Upon Tyne (Spital Tongues)
  • Weather Preferences: Cold, Snow, Windstorms and Thunderstorms
  • Location: Newcastle Upon Tyne (Spital Tongues)

    Thanks Knocker for finding this.

     

    A good overall summary of where we are today (A new word  'disequilibrium' for me is introduced).

     

    A lot work is being put in on the overturning current simulations.

     

    It will be even more interesting to see what happens when the new series of arrays at more northern latitudes release their results.

     

    Also, there seems to be an implicit agreement(?) now that the AMO© is the worlds primary agent for the redistribution of heat between the southern and northern hemispheres..

     

    Which seems amazing that the AMO is still not incorporate in the climate models (as stated in this report)..  

     

    It's in most of the climate models, it's just that it occurs with a range of strengths, some underestimate it, some overestimate and a few are close to reality.

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    So, have you ever wondered how exactly would N Atlantic look like if you would pump out all the water? Well, its one big mountain range (MAR - Mid Atlantic Ridge). It gives you a feeling and a differe

    Yeah, I think that's quite a disingenuous chart (no reflection on yourself , of course!).   If we look at the months used in that chart, and the 9 months leading up to them, we get the following:  

    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 h

    Posted Images

    Posted
  • Location: Solihull, West Midlands. - 131 m asl .
  • Weather Preferences: Sun, Snow and Storms
  • Location: Solihull, West Midlands. - 131 m asl .

    It's in most of the climate models, it's just that it occurs with a range of strengths, some underestimate it, some overestimate and a few are close to reality.

     

    BFTV...

     

    Just noticed your response....

     

    The experts who wrote the paper and obtained and borrowed the model software from its owners in order to run the tests actually made the statement that a only a very few of the models incorporate the AMO and AMOC  overturning effects.

     

    I was quoting from that paper. What is your source?

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    Posted
  • Location: Near King's Lynn 13.68m ASL
  • Weather Preferences: Hoar Frost, Snow, Misty Autumn mornings
  • Location: Near King's Lynn 13.68m ASL

    The RAPID cruise is finished.

     

     

     

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    Posted
  • Location: Hadleigh, Suffolk
  • Weather Preferences: An Alpine climate - snowy winters and sunny summers!
  • Location: Hadleigh, Suffolk

    The November mean SST for the Cold Pool is available and shows it still below the long-term (1948 - 2015) average. I've changed my graph so we can compare 2015 with two other unusually cold years - 1982 and 1993. It can be seen that for most of this year 2015 was heading to being the coldest on record for every month. A slight easing of the anomaly after Sept saw 1982 and 1993 as colder for October, but 2015 remains below the long-term average.

    The figures for Nov:   2015 10.83C    1948 - 2015 Average 11.34C

    The Cold Pool area (courtesy BFTV): 5665e07616cf7_BFTVColdPool.thumb.png.a70  Nov 2015 graph 5665e0933319f_ColdPoolSSTNov2015.thumb.j

     

    Finally, just a quick comment from me about this thread, its worth, and where it should be located. Personally I've learnt an awful lot whilst seeking to understand what might be causing the North Atlantic Cold Pool and will continue to want to keep abreast of developments with the AMO, AMOC, sub-polar gyre, etc., etc. All fascinating and of great importance to our climate. But maybe that is best done in the 'Climate Change - The Science' section, rather than here in the 'Weather Discussion & Chat' area??

    Anyway, I'm looking forward to seeing the RAPID Cruise results. The teams comments about it are a real tease!

    Edited by Blessed Weather
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    Posted
  • Location: limavady N.I 23m ASL
  • Weather Preferences: Cold and snowy
  • Location: limavady N.I 23m ASL

    I too am looking forward to this cruises results. I used data from rapid for uni assignments a couple of years ago to plot up graphs and graphics on erdas imagine. I wish I still had access to it though I doubt I'd remember how to work it. I remember struggling with it at the time but I would like to have a play witness data from this year's cruise across the cold pool there's a few things I'd like to have a poke around at.

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    On 11/27/2015 at 10:39 PM, mountain shadow said:

    A 23 page thread to join the OPI and The Winter Modern in room 101.

    Why so? Maybe only if expecting the cool pool to lead to a colder winter which as suggested was unlikely.

    Firstly the view that it may mean reduced warming of polar air -  the rapid modification by sensible heating of so called marine cold air outbreaks (MCAO) is typically achieved within a few hundred kilometres of the cold land source, by the time the air reaches the cold pool area and then the UK, there is already a fairly deep boundary layer formed with convectional mixing dominated by latent heating, not the SST directly. The cold pool may only lower freezing levels/snow line a little.

    Secondly, the NAO can account for over 50% of the winter temperature in western Europe and the thought is that the cool pool leads to a +ve NAO in winter.

    Using the reanalysis data, a rough estimate of SST for the start of December can be made by averaging the November and December averages (daily data seems a kerfuffle) which is used to create a SST anomaly time series to compare with NAO and CET.

    Correlations are low at -0.11 with NAO and -0.14 with CET and a linearly detrended SST series for long term warming is little better at -0.16 for both NAO and CET - but the tendency is for lower SST in the cold pool area leading to higher NAO and CET.

    Dividing the SST into -ve and +ve anomalies tends to confirm this.

    The below average SST gives anomalies in NAO of +0.17 and CET +0.26°C

    Above average SST - NAO = -0.1 and CET -0.17°C

    The detrended SST anomalies is more marked with below average SST giving NAO +0.14 and CET +0.26°C

    Above average detrended SST gives NAO -0.13 and CET -0.32°C

    So this December is as might be expected from current cold pool SST.

    It's interesting that of the eight Decembers since 1950 with a CET anomaly below -2°C, six have a positive detrended cold pool SST anomaly (2010, 1981, 1950, 1962, 1961, 1995).

    Edited by Interitus
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    Posted
  • Location: Rotherhithe, 5.8M ASL
  • Location: Rotherhithe, 5.8M ASL

    There was mention of it receding fizzling out on the contrary....as of what is now yesterday. Still quite a significant cold SST anomaly which I feel could be useful further down the line.

     image.thumb.gif.8c4448c97a49e5ebc7d572f0

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    Posted
  • Location: Surrey and SW France.
  • Location: Surrey and SW France.
    On ‎11‎/‎27‎/‎2015 at 11:39 PM, mountain shadow said:

    A 23 page thread to join the OPI and The Winter Modern in room 101.

    I have a sneaky suspicion it will still be a talking point come next Spring and Summer.

    qPkn3Rs.png

    The seasonal modelling from CFS fades the current warmth as soon as the atmosphere heats enough to allow the effects of the anomalously cool sea surface to have an impact on westerlies.

    I suspect it is also playing a major part in current synoptics - allowing strong cyclogenesis to take place in a position that draws long fetch south westerlies. 

    Current SST anomaly on a more recent base period.     ZFNazNQ.png

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    Posted
  • Location: Between Sidmouth and Exeter
  • Location: Between Sidmouth and Exeter

    If this summer and now start of winter (in fact the whole year) is a result of the Atlantic cold pool, then it is something that can promptly bugger off. Something that cools our summer and then ruins winter, further reducing our seasonal range.. yeah, just what we need.

    One could think that with our climate, unusual large scale phenomena such as the Atlantic cold pool and El Nino would make things more interesting.. but it seems quite the opposite. Guess it just shows our normal climate is not actually as bad as it could be.

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    Posted
  • Location: Redhill, Surrey
  • Weather Preferences: Southerly tracking LPs, heavy snow. Also 25c and calm
  • Location: Redhill, Surrey
    On ‎22‎/‎11‎/‎2015 at 11:07 AM, BornFromTheVoid said:

     

    It's in most of the climate models, it's just that it occurs with a range of strengths, some underestimate it, some overestimate and a few are close to reality.

    interesting that.  I was at a friend's party last August and we were discussing AGW and climate models.  A guest there who is a close friend of my friend travels the world lecturing on the climate models and what they show and proposed AGW/Climate change projections.  I asked what would they show with this El nino if it became the super nino etc.  Interestingly he said he doesn't know because the climate models don't take into account the ocean's cycles.  And that's from the horses mouth?  So something is astray then, I found that a very odd thing to say?

     

     

    BFTP

    Edited by BLAST FROM THE PAST
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    5 hours ago, Evening thunder said:

    If this summer and now start of winter (in fact the whole year) is a result of the Atlantic cold pool, then it is something that can promptly bugger off. Something that cools our summer and then ruins winter, further reducing our seasonal range.. yeah, just what we need.

    It didn't work out this summer, but along with the tendency for positive winter NAO, the modelling suggests that it encourages summer high pressure downstream which may mean drier and possibly warmer weather depending on exact location.

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    Posted
  • Location: Newton in Bowland
  • Location: Newton in Bowland
    23 hours ago, BLAST FROM THE PAST said:

    interesting that.  I was at a friend's party last August and we were discussing AGW and climate models.  A guest there who is a close friend of my friend travels the world lecturing on the climate models and what they show and proposed AGW/Climate change projections.  I asked what would they show with this El nino if it became the super nino etc.  Interestingly he said he doesn't know because the climate models don't take into account the ocean's cycles.  And that's from the horses mouth?  So something is astray then, I found that a very odd thing to say?

     

     

    BFTP

    I've heard the same  Blast, which begs the question why not as surely oceanic cycles play an important role in climatic temperatures over a long timescale, or I'm I missing something? 

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    Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.

    The phrase 'easier said than done' comes to mind? How do you incorporate a pile of largely unknown 'cycles' into a long-range model, and expect that model to be suddenly taken seriously?

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    Posted
  • Location: Camborne
  • Location: Camborne
    1 hour ago, Hocus Pocus said:

    I've heard the same  Blast, which begs the question why not as surely oceanic cycles play an important role in climatic temperatures over a long timescale, or I'm I missing something? 

    Why do they as they only redistribute heat thus there long term influence on global temperature trends are minute or zero. Anyway if this thread is going to branch out into climate models better make sure we all have a basic understanding of them. And I mean basic.

    Gavin Schmidt at NASA posts an informative explanation of "The Physics of Climate Modeling".

    Real Climate has climate model FAQs located here (Part 1) and here (Part 2)

    And for an evaluation of climate models

    https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&ved=0ahUKEwjrrofQtOrJAhXGcRQKHYieBwcQFgg_MAY&url=https%3A%2F%2Fwww.ipcc.ch%2Fpdf%2Fassessment-report%2Far5%2Fwg1%2FWG1AR5_Chapter09_FINAL.pdf&usg=AFQjCNFzuCyt2E-baTPLWJij4ATbKdpjOg&sig2=pWD8ZhVpmfHrcNHslHlbUQ&cad=rja

    Edited by knocker
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    Posted
  • Location: Newton in Bowland
  • Location: Newton in Bowland

    I get the short term noise thing knocker but when you have long term oceanic cycles at play ( not just ENSO ) then surely these will be factored into the models, or I'm I missing the point?

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    Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.
    10 minutes ago, Hocus Pocus said:

    I get the short term noise thing knocker but when you have long term oceanic cycles at play ( not just ENSO ) then surely these will be factored into the models, or I'm I missing the point?

    I would hardly call ENSO 'long-term', HP...We have hundreds of years' atmospheric data but have barely scratched the surface with respect to the ocean deeps...But then, as you have said, ocean currents are cyclical: what goes around comes around, and surely meaningless as an alternative to GHG-induced long-term warming/cooling trends?

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    Posted
  • Location: Camborne
  • Location: Camborne
    25 minutes ago, Hocus Pocus said:

    I get the short term noise thing knocker but when you have long term oceanic cycles at play ( not just ENSO ) then surely these will be factored into the models, or I'm I missing the point?

    Not sure I can add anything to what I've already posted but you will have noticed that climate models have to be tested to find out if they work. We can’t wait for 30 years to see if a model is any good or not; models are tested against the past, against what we know happened. If a model can correctly predict trends from a starting point somewhere in the past, we could expect it to predict with reasonable certainty what might happen in the future.

    So all models are first tested in a process called Hindcasting. The models used to predict future global warming can accurately map past climate changes. If they get the past right, there is no reason to think their predictions would be wrong. Testing models against the existing instrumental record suggested CO2 must cause global warming, because the models could not simulate what had already happened unless the extra CO2 was added to the model. All other known forcings are adequate in explaining temperature variations prior to the rise in temperature over the last thirty years, while none of them are capable of explaining the rise in the past thirty years.  CO2 does explain that rise, and explains it completely without any need for additional, as yet unknown forcings.

    Where models have been running for sufficient time, they have also been proved to make accurate predictions. For example, the eruption of Mt. Pinatubo allowed modellers to test the accuracy of models by feeding in the data about the eruption. The models successfully predicted the climatic response after the eruption. Models also correctly predicted other effects subsequently confirmed by observation, including greater warming in the Arctic and over land, greater warming at night, and stratospheric cooling.

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    Posted
  • Location: Solihull, West Midlands. - 131 m asl .
  • Weather Preferences: Sun, Snow and Storms
  • Location: Solihull, West Midlands. - 131 m asl .
    1 hour ago, Hocus Pocus said:

    I get the short term noise thing knocker but when you have long term oceanic cycles at play ( not just ENSO ) then surely these will be factored into the models, or I'm I missing the point?

    No -    to answer your points HP, since others are skirting around the issue..

    The ENSO effects where assumed to cancel each other out. (as per Ed's post above). It was also very convenient for the warmers to leave the late 20the century warming effects in to bolster the CO2  effects. 

    The AMO and other effects have not been included in the models.

    There is hope though,  that thanks to the pause as shown in the model forecast warming  (and observed through the actual data), in the last 15 years that both effects will be incorporated in the not too short-term (but not I think until the El Nino effect has disappeared). There is also some evidence that the oceans also have a more long-term climatic effect over 100s of years. These will also be factored in eventually, before the models can be considered a success.  They are also deficient in other areas such as correct feedback analysis.

    So the answer is that yes they will be factored in, but do not expect it to change quickly.

     

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    Posted
  • Location: Newton in Bowland
  • Location: Newton in Bowland

    Thanks for the reply MIA. It seems strange that the PDO and AMO are t included in the data as these have a big bearing on climatic cycles as governed by the 30 year climatic cycles needed to assess data.

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    Posted
  • Location: Surrey and SW France.
  • Location: Surrey and SW France.

    I'm concerned that this diversion may see the thread moved - that would be a shame as it has had a lot of input from people who do not regularly post in the climate section.

    Since we are where we are it would be timely to look at some of the climate modelling from EC earth that does include a range of ocean parameters.

    http://www.to.isac.cnr.it/ecearth/index.html

    Eg. the ENSO forecasts - some very positive episodes modelled but all failed on this big one. I'm of the opinion, looking at the historical periodicities, the model just replicates the past with a warming bias as time goes on.

    I've included the AMOC modelling to have a stab at staying on topic.

    rIJqXdv.png     me4AK1y.png

     

     

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    Posted
  • Location: Camborne
  • Location: Camborne

    Nouska is quite correct and I've no particular wish to continue this digression but just  to add the question of the PDO and climate models has been around for years. A fairly recent paper on the subject.

    Well-estimated global surface warming in climate projections selected for ENSO phase

    Quote

    The question of how climate model projections have tracked the actual evolution of global mean surface air temperature is important in establishing the credibility of their projections. Some studies and the IPCC Fifth Assessment Report suggest that the recent 15-year period (1998–2012) provides evidence that models are overestimating current temperature evolution. Such comparisons are not evidence against model trends because they represent only one realization where the decadal natural variability component of the model climate is generally not in phase with observations. We present a more appropriate test of models where only those models with natural variability (represented by El Niño/Southern Oscillation) largely in phase with observations are selected from multi-model ensembles for comparison with observations. These tests show that climate models have provided good estimates of 15-year trends, including for recent periods and for Pacific spatial trend patterns.

    http://www.nature.com/nclimate/journal/v4/n9/full/nclimate2310.html

    Article

    http://phys.org/news/2014-07-vindicates-climate-accused.html

    Edited by knocker
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    Posted
  • Location: Camborne
  • Location: Camborne

    Observations, inferences and mechanisms of Atlantic MOC variability: a review

    Quote

    This is a review about the Atlantic Meridional Overturning Circulation (AMOC), its mean structure, temporal variability, controlling mechanisms, and role in the coupled climate system. The AMOC plays a central role in climate through its heat and freshwater transports. Northward ocean heat transport achieved by the AMOC is responsible for the relative warmth of the Northern Hemisphere compared to the Southern Hemisphere and is thought to play a role in setting the mean position of the Inter-Tropical Convergence Zone north of the equator. The AMOC is a key means by which heat anomalies are sequestered into the ocean's interior and thus modulates the trajectory of climate change. Fluctuations in the AMOC have been linked to low-frequency variability of Atlantic sea surface temperatures with a host of implications for climate variability over surrounding landmasses. On intraannual timescales, variability in AMOC is large and primarily reflects the response to local wind forcing; meridional coherence of anomalies is limited to that of the wind field. On interannual to decadal timescales, AMOC changes are primarily geostrophic and related to buoyancy anomalies on the western boundary. A pacemaker region for decadal AMOC changes is located in a western “transition zone” along the boundary between the subtropical and subpolar gyres. From this region, meridionally coherent decadal AMOC anomalies are communicated southward. AMOC observations, as well as the expanded ocean observational network provided by the Argo array and satellite altimetry, are inspiring efforts to develop decadal predictability systems using coupled atmosphere-ocean models initialized by ocean data.

    http://onlinelibrary.wiley.com/doi/10.1002/2015RG000493/abstract

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