The Old Man was looking at recent conditions to try for a prediction of next year’s sea ice minimum. More on this shortly; during the research, what came up was the ENSO. It’s neutral at the moment, predicted to be for the next six months. But an eyeball of the Pacific SSTAs raised a question about the direction and strength of the ocean currents, and the direction and strength of SSTAs.
I don’t know if these two are directly linked, but I imagine they are. If this is correct, then it seems reasonable to predict, this far out, that we could be in for a very strong El Nino, starting late in 2009 and continuing for at least two years.
This is mainly based on an interpretation of the 2008 Sea surface temperature anomaly pattern in the Pacific and its relation to ocean current direction and the ENSO area. There is a moderately strong positive anomaly in the Southern part of the West Pacific, stretching along the line of the current in that part of the Ocean, and apparently heading towards South America. There is a huge positive anomaly in the North Western sector, which should be associated with the North Pacific current, which heads towards the US west coast.
On an eyeball analysis, the pattern of Pacific SSTA is a broad clockwise motion in the Nothern hemisphere, and a broad counter-clockwise motion in the Souther Hemisphere. Thus, currents move across the equatorial region from the Americas to Japan (yes, there’s also an equatorial counter-current), go round in a big loop to North and South, and come round the American coasts and back towards the Equatorial region, where ENSO is formed.
There’s vertical mixing to take into account, as well as the flow between the Atlantic and Pacific, but this latter I suspect is a longer-term relationship (which would still, nonetheless, likely exhibit a positive anomaly). There’s a very good chance that a half-competent oceanographer will be able to explain what I’ve overlooked, and that this projection/prediction is nonsense.
Given the trend in global surface temperatures, the current state of NH snow and ice cover, recent ENSO trends and the generally warm oceans, and since my reputation or career is not on the line, I am now going to say that we are probably heading for a monstrous El Nino, starting either late 2009 or early 2010. Why does this matter?
Back to the sea ice. The Old Man’s mind isn’t entirely made up about the forthcoming melt season, though early indicators are that this Winter will be mild in the NH and snow cover (hence albedo) will continue to be well below average. At the moment, the feeling is that there is a chance that 2009’s summer melt will exceed the record set in 2007, but the analysis is ongoing. In the longer term, though, if (big, big if) we get an El Nino in ’09, then 2010 will almost certainly beat 2007. If we have a strong continuing El Nino through 2009 and 2010, then there is a chance that the Arctic Ocean will be effectively ice free (except along the North Greenland coast) in the Summer of 2011.
Definitely want feedback from scientists on this one…
Of course there’s this (hat tip to William), but it is very non-committal.
Edit: There’s a technical description of the recent trends in sea ice loss here: no mention of the El Nino, but the Search/ARCUS summary of 2008 suggests that the current condition will continue until a new warm season triggers another stage of decline.
Old man in a cave 
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October 18, 2008 at 9:46 pm
Paul
Hello Fergus,
I feel that wherever the present position of the Arctic re-freeze, it will mean little next September. The idea of an El Nino which exceeds 1998 is one which I am sure will happen and with continued warming, it is an outcome which is likely to happen sooner than later.
Last year’s conditions in the Arctic have been described as “the perfect wave” by some scientists, ie the combination of warm SSTs and warm synoptics took the record way below anything that was anticipated in March 2007. Given that, this year’s second place seems a reasonable outcome, if the reduction in Arctic Sea summer ice was continuing.
Remember, we had a developing La Nina last year, so the “perfect wave” may not be the best of analogies, as conditions may not have been perfect, at all, in a year where the summer low was described as “stunning” by the NSIDC. If we have an El Nino, one year soon, which exceeds 1998, the gyre connections in the Pacific supplement this and the Arctic melt-season synoptics are similar to 2007……….where exactly will the low be?
I do think next year’s low has every chance of being a record; hence my odds of evens; no record and 4/5; a new record. If anyone really believes that the present freeze has any significance, they must be tempting odds.
October 18, 2008 at 10:14 pm
fergusbrown
Ah, but then there’s this:
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Read Full Article (file size: 582111 bytes) Cited by
GEOPHYSICAL RESEARCH LETTERS, VOL. 35, L20701, doi:10.1029/2008GL035205, 2008
Role of the Pacific-North American (PNA) pattern in the 2007 Arctic sea ice decline
Michelle L. L’Heureux
Climate Prediction Center, NOAA/NWS/NCEP, Camp Springs, Maryland, USA
Arun Kumar
Climate Prediction Center, NOAA/NWS/NCEP, Camp Springs, Maryland, USA
Gerald D. Bell
Climate Prediction Center, NOAA/NWS/NCEP, Camp Springs, Maryland, USA
Michael S. Halpert
Climate Prediction Center, NOAA/NWS/NCEP, Camp Springs, Maryland, USA
R. Wayne Higgins
Climate Prediction Center, NOAA/NWS/NCEP, Camp Springs, Maryland, USA
Abstract
The extreme loss of sea ice over the western Arctic during the boreal summer of 2007 (July–August–September) was accompanied by a very unusual atmospheric circulation pattern. Here we show that the anomalous circulation was linked to a leading climate mode of the Northern Hemisphere, the Pacific-North American (PNA) pattern. The PNA index was three standard deviations above the 1950–2007 mean, and its primary signal in the atmospheric circulation is a strong anomalous anticyclone that was collocated with the location of the greatest Arctic sea ice decline. Therefore, the record-strength PNA along with recent climate trends in the Arctic help to explain the sudden and extreme sea ice melt during the summer of 2007. While the observed PNA was unique, the large decline in sea ice may be further evidence of increased vulnerability to natural atmospheric variability due to a changing climate system.
Received 1 July 2008; accepted 26 August 2008; published 18 October 2008.
But then, I’m still thinking about next year.
October 18, 2008 at 10:41 pm
william
I wanted to test your proposed sea-ice ENSO correlation; but http://climexp.knmi.nl/ doesn’t have a sea ice index. Sadly. I mailed them.
Meanwhile, a quick glance at a sea ice index shows that 1998 was nothing exciting.
October 18, 2008 at 11:28 pm
fergusbrown
For sea ice trends, I find this page useful:
http://nsidc.org/data/smmr_ssmi_ancillary/regions/total_arctic.html
I can’t see the same kind of decline in 1998-2000 as I am suggesting here, following the last large El Nino, so perhaps the correlation is a figment of my imagination, but I think the NSIDC do have some kind of correlation in their analyses.
I’m considering the likelihood of a trend continuing downwards at the extremes (min and max), relative to the underlying temperature anomalies. The baseline is different now for the ice and for the SSTA, compared to ’98, and I am inclined to see the trend since ’98 as noticeably stronger than the preceding decades, in other words, as accelerated.
I was also toying with the range differences between min-max and max-min series; the range appears to be relatively stable. This would suggest that this winter season won’t recover to much above 13.5 Mkm2 (on the CT measure), setting up next year to drop to around 3-3.5. It would not take much positive forcing to imagine the following year reaching a new extreme low, which I take to be implied by the general conditions associated with an El Nino.
But I am not being scientific about this; it’ still all hunches and playing with the graphs/numbers/trend lines. I’ve emailed Bob Grumbine to solicit his opinion, perhaps others in cryospherics will have their thoughts. I’m guessing you’re still inclined to see the overal trend as not being dominant enough to suggest, on its own, a new regime in the Arctic, but I suppose I’m saying here that i think that, whilst we may not be at a ‘tipping point’, we probably are in a situation of such sensitivity to the wrong kind of conditions that any kind of unusual forcing will be enough to push the summer minimum to near-zero (or, at least, below ’07).
Regards,
October 19, 2008 at 2:16 pm
Bob Grumbine
A bit of thinking off the top of my head, and a little more seriously analyzed stuff too, since you invite it.
On ENSO to sea ice, I’ve done some more serious analysis between the Southern Oscillation Index and ice cover. My analysis was by grid points in the ice pack, rather than regions, so could miss more subtle things. On the other hand, it’s rather similar to what I’m guessing is behind William’s map, and I did do it for more than just concurrent. The upshot (never published the work; I should really pull it out and do so) was that as William’s figure suggests, and has been published in the literature some, there’s a response in the Antarctic to the SOI. It’s higher for an appropriate lead than for concurrent, and passes the 5% level (or better).
Unfortunately, you’re looking at the Arctic and I have weakly bad news for you there. I didn’t see much meaningful correlation, even with lead/lag relations, between SOI and the Arctic ice. It’s only weakly bad news because, as I said, I didn’t analyze areas. If I’d taken the entire Chukchi or Beaufort seas, it’s possible that a signal obscured at the gridpoint level would have emerged. Then again, maybe not. I have better ways of doing such an analysis now, so, again, time to dust off those codes and kill off a paper.
As for records and such … I’ve been trying to decide what the best mental image is. I was reasonably confident that there wouldn’t be a new record this year, but did expect it wouldn’t be that far away from last year. So the intuition held up ok this time. For now I’m going with something of a mode change. One part of that is to, first, ignore 2007 and 2008. I don’t think that a straight line is the best representation of what was happening to the minima before then. What exactly I do think, I still have to work on. I have ideas, but it’s one thing to eyeball and another to do the math.
One thing certainly going on was a thinning of the ice pack and some other oceanographic shifts. That set up conditions where the unusual 2007 meteorology could blow away so much of the ice pack. Having done so, the question moves to whether it causes a continuing shift (ice albedo feedback finally getting to run amok), shifted the notion of ‘normal’ (as in 2008 being pretty similar to 2007 even though there wasn’t the extraordinary meteorology), or we just have a 2 year bizarre spell and 2009 will be more like the 1979-2000 climatology (I would take a bet of honor against it — William, you reading?)
Of the three, I think the new mode is the most likely. So at this point, I’d look for 2009 to be ‘around’ 2007-8, rather than either ice free or the prior means. … unless there’s another extraordinary summer meteorologically, in which case, ice free becomes plausible, as does a shift towards 1979-2000 averages. Between these two, the ice free seems more likely.
Almost all the above being thoughts off the top of my head, rather than research statements. So take with grains of salt.
October 19, 2008 at 3:07 pm
fergusbrown
Thank you, Bob, for your sterling response.
Without the expert justification, I’m very much in agreement with your overall ‘picture’. I’ll say straight out here that I’m not fixated on record breaking (like William, I think its a distraction from more important matters), but it does make for a good headline.
A look at the anomaly trend on CT’s ‘Tale of the tape’ suggests a mode shift since approximately 1998-2000. Taking away the last two seasons, there’s still a different trend line to the 1979-2000 pattern. If we assume that the past two summers are a part of this longer trend, then ’09 is more than likely to be close to the last two years, just on best fit. It would be interesting to consider what conditions might be required to return the sea-ice summer cover to something closer to either 2000 or 2004 (’05 being another record year), and whether these conditions are in any way likely.
I do think there’s a good fit to be got from looking at the range of difference in coverage between maxima and minima, since this also has a recent trend, but it is also relatively smaller in variation (+/- 10-15%, I’d guess). Naturally, the trend is for a steady divergence over the time period, but the divergence looks reasonably linear, certainly modellable.
From this, I’m thinking that the winter maximum level in March is going to be a meaningful predictor for the final summer extent/area. This can either recover to a level close to the 1979-2000 average, close to the 1998-2005 average, which is lower, or close to the 2006-07 amounts, which were below the long term averages by some way. My guess is that the recovery is liekly to show an anomaly of -0.7-1.0Mkm2. If it is closer to the larger anomaly this winter, then ’09 will be very close to the last two seasons. Only if the winter maximum is anomalous by less than -0.3Mkm2 will I start to wonder of the past two summers have been outliers, rather than trendsetters.
Once again, thanks for your valued time.
October 19, 2008 at 11:13 pm
Bob Grumbine
Always good to see an interest in the cryosphere and science rather than hype.
And let me encourage you and your readers to come by my place with questions. Some times they’ll become posts, as is happening now with a question from Steve Bloom, and some times I’ll answer them in place. There’ll always be a ‘question place’ note available.
If you’re in the area, you’re also welcome to come by the Annapolis Science Cafe, Thursday, October 30th, 6:30 PM (or 5:30 if you want to get something to eat first), at the 49 West Cafe. I’ll be talking, and, more fun, fielding questions, about sea ice. Figure about 15 minutes of me starting things off, and 45-90 minutes (depending on whether a group is coming in behind us) of time for questions.
If you’re not in the area, look up http://sciencecafes.org/ for whether there’s one near you. If there isn’t, start one!
October 20, 2008 at 1:51 pm
fergusbrown
Unfortunately, I’m in Portsmouth UK, not Portsmouth MA or VA, so Annapolis might be a bit of a stretch, what with the job and all.
The promotion of science is a great idea. Our city has over 15,000 university students; I suspect there’s a cafe somewhere, where the intelligentsia meets, but I’m damned if I know where it is.
You’re already on my visit list (and bloglist); I’ve been using your MMAB stuff for a couple years now to help in understanding cryospherics.
October 24, 2008 at 1:22 pm
CL
Hmmm…not so sure I agree with the reasoning for the prediction of a giant El Nino event…it’s not particularly in agreement with contemporary theories on ENSO dynamics…sea ice extent may be related to ENSO, I don’t know. I do know that sea ice it is certainly not a driver pf the phenomenon, a ‘boundary condition’ at best. It’s probably not a very good predictor, esp a year down the track.
It is also pretty hard to image a greater El Nino than 1997-98, I suspect that event probably represents something close to the maximum potential that can be released by the system. During that event, the water was 28+ C across the entire equatorial Pacific. It doesn’t get any warmer than that…
Recent MEI numbers (and SSTs ) still suggest we are still neutral to weak La Nina conditions. The nearest historical analogy for the current period is the 73-75 period, the mother of all La Ninas. It wouldn’t be unprecedented to see a second hump of a double-dip La Nina next year…Interestingly, the earlier event occurred just before the SH ‘climate shift’ in 1976…
We could speculate (idly?) that these events are a harbinger of a new mode of global ocean circulation (including the sea ice?) developing…There are odd goings-on in the Indian Ocean as well, i.e. three positive Indian Ocean Dipole years in a row. Perhaps these events are not caused by climate change, but rather *are* the climate change…
October 24, 2008 at 4:24 pm
fergusbrown
Hi CL and thanks for visiting.
I don’t know enough about the vertical circulation in the Pacific. Even if I did, I’d still be speculating beyond the bounds of model predictive skill.
I suspect that my imagined correlation (though this is really William’s take on my comments; I was originally imagining that an El Nino and sea ice loss would be linked temporally rather than causally) is unlikely to pass muster; Bob’s comments above are informative here.
I see a large warm anomaly in the western north pacific. There has been a persistent decline for several years in sea ice in the Bering, Chuckchi, Okhotsk areas. I see the warm anomaly heading eastwards towards the US. I know the Cal. current, for example, draws water southwards towards ENSO 1. There is a comparable pattern in the SH (with a greater degree of uncertainty). However, I think I’m right saying that we need to look closely at the Caribbean/Gulf of Mexico, too, for indications suggesting increased heat being transported across the isthmus.
Whether any of these three ocean temperature anomalies can be linked to EN prediction is beyond my knowledge at the moment, but I am working on it.
I don’t see sea ice conditions as impacting on ENSO conditions.
You are quite correct that it is just as likely that we will see a Nina as a Nino. I just happen to have a particularly vivid imagination.
Your final paragraph is a real teaser. I’m going to think about this and possibly promote it for further comment.
Thank you for contributing
September 16, 2009 at 5:52 am
Shannon
Hi there,
My name is Shannon and i am a student, who is at the moment studying El Nino in science. I am very interested in all this stuff about it all.
But is it true that we may be in for terrible hot, warm weather? It’s hard enough living in darwin, what with the build up and humitdity and stuff. If we are in for terrible weather, is there anything we can do? Will Darwin still have rain or will it be decreased?
Oh and one more question; is the Antarctica and the Arctic on the peak of a melt down; LITERALLY?
Thanks for reading this and I hope you can help me a bit, so i can understand El Nino a bit more and be prepared for the worst. 🙂
September 16, 2009 at 2:43 pm
fergusbrown
Hi Shannon and thanks for visiting. I was very fond of a Shannon from Minnesota when I was a student myself.
There is a lot of material available on El Nino from NOAA in the USA: I’ll post a link to the regular discussion page soon; they have a major meeting every month and run ongoing analysis in great detail.
There is also a lot of material available which is specific to the Pacific, both from Australia and Japan.
With regard to Darwin, are you looking at the long-term weather forecast, or asking about the future climate? It’s hard to know from the way you phrase your question.
I am not up to date on the el nino or the Darwin forecasts: I’ll take a look.
Are the ice caps on the brink of a meltdown? Depends who you ask, what you mean by a meltdown, and what timescales your are thinking in. You have entered into an area where few things are certain and opinions (even within science) vary.
If you want to pursue your interest, I suggest you spend some time ‘googling’ under various headings, and look for websites which you think are rational and (broadly) scientifically based, do some background reading, and ask more questions.
More on this later.
Best. F
September 16, 2009 at 2:45 pm
fergusbrown
Here’s that link:
http://www.cpc.noaa.gov/products/analysis_monitoring/enso_advisory/
🙂