2014 ENSO Mega Thread

[Bob Chill]

To get back to a more solid +PDO, I'd like to see the Aleutian waters cool back down.

We'll see how the next 2 weeks shakes out. Looks pretty favorable on the 5 day means for pdo region to cool as a whole from where we are now. I just don't want to see a continued decline this month. That would make 6 in a row.

ETA: would make 5 in a row and not 6

[JBG]

Does anyone think the very warm waters in the Western Pacific could be signaling a change from the +PDO we've been seeing to perhaps a more neutral to even negative phase?  If you look at the SST anomalies, the Pacific looks very neutral currently...not nearly as positive as we've seen the past several months.  I don't want to hijack this thread, but if we are switching back to a negative phase, it could explain why we've been struggling with this Nino, which looked like a slam dunk just a few months back.  

Aren't we in a long-term decadal negative phase?

[GaWx]

Aren't we in a long-term decadal negative phase?

 

We're in a longterm -PDO REGIME as opposed to PHASE imo. Perhaps Kory agrees. The semantics are confusing.

[Kory]

Aren't we in a long-term decadal negative phase?

Yes we are. GaWX has better terminology than I since I tend to use phase interchangeably. But since about 2006 or so it appears we've entered a long term negative regime.

[JBG]

We're in a longterm -PDO REGIME as opposed to PHASE imo. Perhaps Kory agrees. The semantics are confusing.

 

 

Yes we are. GaWX has better terminology than I since I tend to use phase interchangeably. But since about 2006 or so it appears we've entered a long term negative regime.

Is it the "regime" or "phase" that effects the frequency and strength of ENSO phases? Do I recall correctly that the 1957-8 El Niño was during a positive phase that occurred during a negative regime?

 

Also and a bit off topic, wasn't the 1960-1 winter, which seemed similar to this past winter, also a +PDO phase winter with a +NAO and no blocking? Both 2013-4 and 1960-1 seemed marked by frequent snowstorms and bitter cold,with the last storm of each both big and the only ones with P-Type issues?

[Bob Chill]

Yes we are. GaWX has better terminology than I since I tend to use phase interchangeably. But since about 2006 or so it appears we've entered a long term negative regime.

Yep, but like with any decadal oscillation there's still volatility. Since enso/pdo share some of the same fingerprint, warm enso events highly favor a neutral +PDO config.

[GaWx]

 The U of Washington number was just released for August: +0.67.

 

 http://jisao.washington.edu/pdo/PDO.latest

 

 The +0.67 isn't chickenfeed +PDO phasewise. It is near the 82nd percentile for August +PDO's going back to 1900.

 

 There have been only 20 Augusts with a higher PDO.  18 of the 20 subsequent DJF's averaged a +PDO.

 

There have been 9 Augusts with a PDO in the +0.40 to +0.66 range, I.e., just a little lower. Six of those nine went on to have a +PDO averaged over DJF.

 

  Six of those Augusts were within +0.40 to +1.00 and were within new/oncoming El Nino. Five of those six went on to have a +PDO averaged over DJF.

 

 I'm still going with an 80% chance for the U of Washington upconing DJF to average a +PDO.

[Kory]

Yep, but like with any decadal oscillation there's still volatility. Since enso/pdo share some of the same fingerprint, warm enso events highly favor a neutral +PDO config.

Oh I know. You can look at the 2009-2010 Nino and it went positive for several months.

[Bob Chill]

Oh I know. You can look at the 2009-2010 Nino and it went positive for several months.

 

I know you do. My post was more in response to jbg. 

 

GaWx,

 

While the index came in at .67, the current state and trend of the ssta's in the PDO region tell a different different story. I have no idea what the exact calcs are but from what I'm seeing, most of the + state was early month. Right now I don't even think the index would be positive. It's been a terrible month for the that area of the Pac. 

 

Look at this animation. We need things to reverse. Plenty of time before it matters but if the current trend continues I won't be happy at all. 

 

 

[Kory]

I know you do. My post was more in response to jbg.

GaWx,

While the index came in at .67, the current state and trend of the ssta's in the PDO region tell a different different story. I have no idea what the exact calcs are but from what I'm seeing, most of the + state was early month. Right now I don't even think the index would be positive. It's been a terrible month for the that area of the Pac.

Look at this animation. We need things to reverse. Plenty of time before it matters but if the current trend continues I won't be happy at all.

My question is if we're truly in the -PDO regime, then eventually this trend has to revert back to negative. It can only stay positive so long.

One thing for sure, the northern hemisphere oceans are very warm. Just look at the North Pacific and Atlantic.

[JBG]

It's interesting that the short term shift to the +PDO this year wasn't El Nino driven like we typically see when the PDO rises during the winter. The +PDO rise this year was the result of the record NE Pacific blocking pattern from 2013 into 2014. The classic +PDO is El Nino driven with a strong NE Pacific low pressure pattern.

Wasn't that similar to 1960-1?

[JBG]

In that the January 61 the PDO rise occurred during ENSO neutral conditions. But the 500 mb pattern that

winter looked more like an El Nino with the very strong Aleutian low boosting the +PDO/-EPO.

In what ways was 2013-4 different?

[JBG]

We had the record breaking ridge which lead to the historic California drought.

No such ridge in 1960-1?

[Bob Chill]

No such ridge in 1960-1?

 

This is a handy link. Just pick the months and year and pull an anomaly composite at any height level. 

 

http://www.esrl.noaa.gov/psd/data/composites/day/

[GaWx]

I know you do. My post was more in response to jbg.

GaWx,

While the index came in at .67, the current state and trend of the ssta's in the PDO region tell a different different story. I have no idea what the exact calcs are but from what I'm seeing, most of the + state was early month. Right now I don't even think the index would be positive. It's been a terrible month for the that area of the Pac.

Look at this animation. We need things to reverse. Plenty of time before it matters but if the current trend continues I won't be happy at all.

Bob,

I just looked at the animation and agree that the trend from the first pic (early August) til the last pic (early Sep.) strongly suggests a PDO drop. The dateline area has warmed quite a bit. That tells me that the first half of August likely averaged higher than +0.67 and the second half under +0.67. So, the trend during that period had to have been down. IF that trend were to continue for much of the autumn, it would certainly reduce the chance for a +PDO winter. However, the good news is that longer term stats suggest a good chance for a reversal at some point this autumn. Also, the expected Niño likely would, itself, help raise the PDO at least some IMO. We'll see. These things often tend to slosh back and forth as you may suspect.

[Bob Chill]

Bob,

I just looked at the animation and agree that the trend from the first pic (early August) til the last pic (early Sep.) strongly suggests a PDO drop. The dateline area has warmed quite a bit. That tells me that the first half of August likely averaged higher than +0.67 and the second half under +0.67. So, the trend during that period had to have been down. IF that trend were to continue for much of the autumn, it would certainly reduce the chance for a +PDO winter. Longer term stats suggest a good chance for a reversal at some point this autumn. We'll see. These things often tend to slosh back and forth as you may suspect.

 

I really have no clue which direction we go in months down the road. Basically equal odds in my mind at this point. However, I do think we will see improvement over the next couple weeks. How much if any and how it plays into the future is way over my head. 

 

Sure would like to see a noticeable improvement in 3.4. If that starts taking shape the next couple months then other things may fall into place by default.

[Kory]

I really have no clue which direction we go in months down the road. Basically equal odds in my mind at this point. However, I do think we will see improvement over the next couple weeks. How much if any and how it plays into the future is way over my head. 

 

Sure would like to see a noticeable improvement in 3.4. If that starts taking shape the next couple months then other things may fall into place by default.

They have some serious downwelling occurring with +4 degree C anomalies taking place.  We're a few weeks away before we see the big anomalies surface.  Gotta be patient with this special Nino.    

[The_Global_Warmer]

CPC finally updated sub-surface for the week.  It's not as warm obviously as the April wave.  But it's decent and covers almost the entire equatorial region.

 

 

 

 

We can see the impact of the kelvin wave in the latest wind forecasts.

 

 

 

 

[Bob Chill]

They have some serious downwelling occurring with +4 degree C anomalies taking place.  We're a few weeks away before we see the big anomalies surface.  Gotta be patient with this special Nino.    

 

Patient is an understatement considering what we were thinking back in April-May. lol

 

 There's still plenty of time. Latest anom plot looking better than it has in a while. A little cooling near the Aleutians, +pdo may be rebounding and 3.4 improving. If conditions remain favorable and we don't take another step or 2 back during the process we could be in decent shape overall. I think most agree that a classic 02-03 or 09-10 is off the table unless things completely break our way for weeks on end. 

 

If I had a gun to my head, my wag would be a peak trimonthly in the .8 - 1.2 range and peak 3.4 temp around 1.4 or so. May be too optimistic but I'm an optimist so...

 

u

[GaWx]

The SST anomaly map that Bob posted just above seems to often jibe with the Levi Cowan satellite based number, which has just risen to +0.285 in Niño 3.4. This is the highest it has been since 7/20 fwiw.

http://www.tropicaltidbits.com/analysis/nino34.png

[The_Global_Warmer]

So if I understand this graphic correctly.  The forecast starts with relatively neutral winds with weak Westerly winds around 120E which essentially around Indonesia. 

 

There has been Westerly winds around the central Pacific that have helped the sub-surface warmth propagate Eastward like we have seen this past month.

 

Now the forecast shows Westerly winds increasing over the CPAC equatorial region.  Quickly spreading East over the Eastern half of the ENSO 3 zone while also increasing in strength.

 

It also shows a Westerly wind burst near the SA coast by the ENSO 1-2 regions.  Is that going to help flatten the "thermocline"? 

 

 

It also shows Easterly winds next week on the WPAC side.  Is it normal to have strong Westerlies literally on the Eastern half with strong Easterlies on the Western half at the same time?

 

 

Wouldn't that mean warm water on the West side would be suppressed and pushed Westward.  And warm water on the East side would continue to be pushed towards SA and start surfacing?

 

What then comes and fills in between them?

 

 

 

 

[GaWx]

The SST anomaly map that Bob posted just above seems to often jibe with the Levi Cowan satellite based number, which has just risen to +0.285 in Niño 3.4. This is the highest it has been since 7/20 fwiw.http://www.tropicaltidbits.com/analysis/nino34.png

As of 0z today, Levi's graph fwiw shows +0.394. So, it has risen 0.109 in just 18 hours. It hasn't had this steep a rise since the big rise of around 6/20 (which was largely ignored by the NOAA weeklies). However, unlike then, we have a supportive prevailing -SOI.

http://www.tropicaltidbits.com/analysis/nino34.png

Bluewave, 1935-6 was a neutral positive that produced about the wettest winter on record at Atlanta fwiw. It was also a top ten cold winter there. It was one of the greatest winters there ever. It was quite a cold winter for much of the E US. However, very cold neutral positive winters have been fairly rare there and in the E US in general. Usually a weak El Niño is needed for that.

[Bob Chill]

Yeah, what happens between now and the end of October will tell the tale. A good sign the atmosphere is going into

El Nino mode would be a strong Aleutian low and -EPO ridge couplet in October. It will be interesting to see how

things go over the next 6 weeks.

We are entering the 4th quarter with only a small lead but the trend the last 4 weeks or so has been good but agonizingly slow of course. The pattern over the entire npac basin over the next 2 weeks looks decent to prime that area. From what I'm seeing, the AN ssta's south of the aleutians and western goa is going to take a hit. How much and whether there is enough response to continue is tough to say. I'm expecting the state of the pdo to improve after the continuous decline during August.

Enso regions are also taking on a more classic appearance but fragile to say the least. That area is primed to improve as we move forward it's a wait and see. If things break our way we could be in solid weak nino state by mid-late Oct.

[griteater]

This year is turning out be an unusual case so far. We are getting the current subsurface warming from 

August into September, but the trades are still staying up over the Western Pacific.

A recent westerly wind burst is skewed further east than normal probably due to the very warm

SST's over the Western Pacific. So it will be interesting to see how much 3.4 will warm over

the next 6 weeks.

 

Given the subsurface conditions and the projected westerly wind anomalies, I would expect to see some warming in Nino 3.4 over the next few weeks.  The TAO ground truth is showing some solid westerly anomalies right now near and west of the dateline.

 

 

 

Here's an alternate view of CFS modeled westerly wind anomalies in the near term (hard to trust it past a week or two)

 

 

 

Along with Nino 3.4 SSTs being slow to reach nino threshold, 2 other things that haven't been consistent with a nino are: 1) The lack of persistent westerly wind anomalies in the western pacific (as you've been outlining in your posts bluewave), and 2) the lack of persistent convection / cloudiness near the dateline.  Here's a Jul-Sep composite of oncoming weak nino years (ONI) which shows the -OLR (higher than normal cloudiness) that you would normally see.  Instead, the OLR values have been running around neutral since early May - http://www-cluster.bom.gov.au/climate/enso/#tabs=Cloudiness

 

[GaWx]

Bluewave,

 Can you even find one Nino with similar warmth in the W Pacific in September? How far back can you look?

[GaWx]

 Per today's TAO, the western and central areas of 3.4 warmed considerably vs. yesterday TAO fwiw. Also, it shows quite the westerly wind anomaly in region 4 just west of the westernmost 3.4. Together with the significantly warmer Levi Cowan satellite based graph over the last several days and the continued solid -SOI average, we appear to be on the verge of finally getting the Nino going. I'm still predicting weak to possibly low end moderate for the fall/winter peak. 

[The_Global_Warmer]

Given the subsurface conditions and the projected westerly wind anomalies, I would expect to see some warming in Nino 3.4 over the next few weeks.  The TAO ground truth is showing some solid westerly anomalies right now near and west of the dateline.

 

 

 

 

Here's an alternate view of CFS modeled westerly wind anomalies in the near term (hard to trust it past a week or two)

 

 

 

Along with Nino 3.4 SSTs being slow to reach nino threshold, 2 other things that haven't been consistent with a nino are: 1) The lack of persistent westerly wind anomalies in the western pacific (as you've been outlining in your posts bluewave), and 2) the lack of persistent convection / cloudiness near the dateline.  Here's a Jul-Sep composite of oncoming weak nino years (ONI) which shows the -OLR (higher than normal cloudiness) that you would normally see.  Instead, the OLR values have been running around neutral since early May - http://www-cluster.bom.gov.au/climate/enso/#tabs=Cloudiness

 

 

 

Is that thing predicting Westerly wind burst over the Western Central Equatorial region for 3 months in a row?  Is that a normal Fall thing or am I reading that graphic wrong?

 

Wouldn't that reinforce an el nino pretty good?

[griteater]

Is that thing predicting Westerly wind burst over the Western Central Equatorial region for 3 months in a row?  Is that a normal Fall thing or am I reading that graphic wrong?

 

Wouldn't that reinforce an el nino pretty good?

 

Yeah, that would keep the warming coming...but again, hard to trust it past a week or 2

[The_Global_Warmer]

Yeah, that would keep the warming coming...but again, hard to trust it past a week or 2

 

 

Has that long of a Westerly wind burst ever happened before?

 

It seems like a very long time compared to how it's been since I started following enso in 2011.

[Bob Chill]

Really interesting pattern setting up over the npac basin next couple weeks. There are going to be big changes in the ssta config if it verifies and there's plenty of support. Especially for the goa region. That warm pool is going to take some hits. Probably doesn't mean much in the long term. It can change quickly. But it's been there for many months. Could be a good example of how fast things can change.

PDO region is likely going to improve quite a bit as well. Also looks like modest improvements will continue in 3.4. I think we'll all like how the Pac looks going into Oct.