http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf
her is the latest more nuanced NOAA discussion on La Nina.
That's a very interesting read, thanks.
The temperature and precipitation anomay charts for the US are especially interesting - the impact of La Nina is quite stark through the winter months, becoming more pronounced as the winter progresses. Pity they don't include Europe or the Northern Hemisphere.
Looking at the tables, I notice that 1962-63 had a weakish La Nina... I think it's been said before but worth repeating.
I would not use ENSO as a guide to UK winter weather except as one of a number of variabes, as the statistical links are weak. Just because last year we started cold and ended mild, in line with the general pattern of correlation with La Ninas, doesn't mean this was a direct result of the Pacific.
MJO activity has been relatively strong in recent weeks, which has weakened the progression towards La Nina. Now we are into November I would think the cards are probably marked and we will end up with what the majority of models are showing - mild to moderate LN, weaker than last year with a slow warming early next year.
The sun is no longer 'quiet' by the way. Current sunspot number is 142, for example, and the October mean was 123. That is about half way to the levels of the last solar max in 2001, with about a year to go until the maximum. So if we really are headed into a grand minimum, it will not be until the next cycle.
Thought I would post about the current status of ENSO as its been a few weeks since the last post
www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/images3/nino34SSTMon.gif
Unsurprisingly the La Nina forecasts has been moderated since the last time I checked (about a month ago). Some pretty strong La Nina's there amongst the bunch of forecasts from the CFS. Overall though I would expect a moderate La Nina to occur, something a bit stronger then 2008/2009.
The La Nina appears to ease through Spring then slowly form back in the Summer of 2012 again, I don't know whether this is unusual or not because as we approach the middle of Spring we get the 'Spring Predictability Barrier' which ususally causes a very large amount of scatter amonst the ensembles as they are unsure as to where ENSO will go next.
Edited by user 28 November 2011 23:39:21(UTC) | Reason: Not specified
It almost certainly won't keep stregnthning through to March. It will reach its peak anytime between now and Chrirstmas and then slowly fade.
I don't really see it getting much more intense than it is now, to be honest.
CFS v.2 is pretty much there now;
http://www.cpc.ncep.noaa.gov/products/CFSv2/images3/nino34Mon.gif
Keeps La Nina basically around -1.0 through to early next year when it goes back to neutral.
Edited by user 03 December 2011 11:07:03(UTC) | Reason: Not specified
Lets hope thats an outlier. Or else GW is about to kick in in a way never seen before...
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/images3/nino34SSTMon.gif
I didn't even see the rogue run at first - just that the average was, err, above average.
I think CFS is having a few technical difficulties.
Are the latest runs (blue) here suggesting the La Nina is gonig to get stronger? or is it still having technical problems? I'd be very surprised if it does get much stronger
CFS V2 for example sees ENSO gradually heading towards neutral early next year
Edited by user 11 December 2011 12:17:38(UTC) | Reason: Not specified
CFS V2 suggests that La Nina is at its peak now and won't get any stronger (-1.0, weak to boarderline moderate)
I've no idea what CFS V1 is on by predicting it to get stronger into spring 2012.
Edited by user 11 December 2011 12:38:33(UTC) | Reason: Not specified
CFS V2. Now keeping La Nina above -1 through the winter, in other words its predicting a weak La Nina;
Amazing considering even CFS V2 was forecasting an intense La Nina just a couple of months ago, while CFS V1 was predicting a mega event.
Edited by user 21 December 2011 11:49:01(UTC) | Reason: Not specified
Looks like ENSO is going to head to neutral within two months, not surprised really, what is telling is the number of +VE EN3.4 members on there (blue runs show the most recent forecasts), this is the first time I've been consistently monitoring ENSO, is it unusual to see the amount of +ve members at this stage?
Edited by user 30 December 2011 14:18:52(UTC) | Reason: Not specified
It appears La Nina has paked and his now weakening across all Pacific regions;
http://www.weather.unisys.com/surface/sst_anom.gif
http://www.osdpd.noaa.gov/data/sst/anomaly/2012/anomnight.1.16.2012.gif
In the end it didn't go much above -1.0, so it was a weak to boarderline moderate event;
So much for the recordbreaking La Nina the silly CFS model was forecasting just a few months ago;
http://www.cpc.ncep.noaa.gov/products/people/wwang/cfs_fcst_history/201110/images3/nino34SSTMon.gif
Edited by user 17 January 2012 10:12:43(UTC) | Reason: Not specified
That's a pretty big over-estimation over a pretty small time span? And if we have a similar 'under-estimation' of the spring/summer outlook?
For some reason I'm waiting of a pretty strong nino over the next few years, I wonder if it is this one?
With some of us waiting for news from the Siberian shelf the remembrance of how temps used to run a few years back (compared to the past couple of years....low solar?) the spectre of us resuming the heat we saw across the pole through the nineties and early noughties is a tad unwelcome!
Watching for snow this winter has thrown me back 3 years to the 'rollercoaster ride' of cold appearing out in F1 only to have gone by the time we get into a 'reliable timeframe'. So I wonder if we'll see the same across summer with projections of an average summer overwritten by another 03' Is agw now so underlying the natural that a small shift in 'the natural' pushes us into our 'warmer world'? if so then the past two Nina's were driven by PDO-ve and low solar but moderated to what we have seen by the 'background' AGW?
The moral of the story is that CFS is quite good at picking up the general direction of travel, but lousy when it comes to predicting the stregnth/longevity of these events,
As far as El Nino goes, remember we've already had quite a strong event in 2009/2010, so my guess is the next El Nino will probabaly be somehwhat weaker than 09/10.
Edited by user 17 January 2012 10:13:18(UTC) | Reason: Not specified
As background global temps creep up then many of the 'average' Nino's will produce effect near comparable with the 98' 'Super Nino'.
Though 'strong' the last Nino was nowhere near a 'super Nino' yet it's impacts were similar? (and remember we're supposed to be either mid PDO-ve (ie the phase impacts at it's strongest) or at the beginning of a PDO-ve phase (which should still 'moderate' the Nino?) and under very low solar over the period of our last Nino so how 'strong' would it have been with high solar and +PDO??.
Last years paper on the impacts of AGW on the PDO cycle did highlight that from the 80's onward the global temps were impacting the PDO phases (moderating the -ve phases and augmenting the positive phase). Surely this trickles down to the Nino/Nina events?
Edited by user 17 January 2012 11:09:24(UTC) | Reason: Not specified
The other thing we shouldn't forget is that the trickling down to Nino/Nina events should be noticeable with rising "whole ocean" temperatures - but, atm, the expected rise hasn't been found?
But it's accepted that the oceans are vast and we don't know how much energy is being absorbed into the body of the ocean as opposed to the surface layer, do we?
I am reminded on Stephen's odd assertion that warmth from the MWP was retained in the ocean depths for hundreds of years. I don't buy that but you have to accept that we don't understand enough about this. The surface layer can only be, what, a fraction of 1% of the total?
the trickling down to Nino/Nina events should be noticeable with rising "whole ocean" temperatures - but, atm, the expected rise hasn't been found?
A recent paper by von Shuckmann and Le Traon concludes that ocean heat content is rising:
http://www.ocean-sci-discuss.net/8/999/2011/osd-8-999-2011.pdf
So the paper is saying that the decadal temperature rises can't yet be determined as not being part of interannual ocean changes - which imo are large indeed.
More time is needed.
Edited by user 19 January 2012 09:29:48(UTC) | Reason: Not specified
IOD model looks to going for the re-emergence of weak El Nino this summer;
http://www.jamstec.go.jp/frcgc/research/d1/iod/
Big turn around in Pacific equatorial temperatures from spring to summer.
Edited by user 20 February 2012 21:37:44(UTC) | Reason: Not specified