• Hello, please take a minute to check out our awesome content, contributed by the wonderful members of our community. We hope you'll add your own thoughts and opinions by making a free account!

Pattern ENSO Updates

^ Here are some quotes regarding Mike Ventrice's AEI:

1. This 1st one is from a usually good quality poster: "I think Mike Ventrice's index might be too focused on the tropical Pacific particularly rainfall patterns between the Maritime and the central Pacific, though to be fair I'm not certain what goes into his index."

2. "I have never been impressed with Ventrice, particularly on the ENSO topic."

Response to this one: "As in not impressed with his indices? He works for IBM/TWC. His job is to develop new ways to analyze long range forecasts for their (mostly) energy clients. Some of them work. Some of them have issues."

3. "I wish Ventrice worked on improving key ENSO variables that actually matter. The current variables that we know of are still pretty complicated and mysterious in how and why they work. So if someone with all his resources can invest them in these key indicators, then I would think it would do a lot of good."

My point in showing these is that there is currently a lot of uncertainty regarding the usefulness of the AEI.
 
Webberweather53 said:
2. You're missing my point... The relationships while significant are less so than every other ENSO index to date, and yes occasionally every other ENSO index may be misleading at times, and there's solid data for other indices going back 150 years, but the SOI is usually more misleading more often than any other (see Wolter and Timlin (2011)) and I strongly caution against its utilization for real-time monitoring. I'm pretty sure I know what I'm talking about given some of my extensive research w/ a host of ENSO indices and creation of the ENS ONI, NCEP-NCAR MEI, ENS-SOI, etc...

3. The TAO buoys have a warm bias of about 0.1-0.2C in comparison to all other SST data available and the data is heavily interpolated, adjustments are needed to make the data useful and comparable to other data platforms, Levi's CDAS1 data is fairly reliable as is the OISSTv2 data. I know this first hand in my creation of my ENS ONI (which uses NINO 3.4 SSTAs) wherein I removed TAO and ARGO data because both sources had an extreme warm bias particularly during ENSO neutral and La Nina regimes...

4. I'm actually a big fan of the MEI. A) The MEI integrates multiple variables across multiple platforms (6), I use 7 in MEI NCEP-NCAR MEI to derive a relatively stable and coherent ENSO index that's available in real-time and in doing so is able to capture more variability than the SOI or NINO 3.4, particularly non-linear variance that variables such as SLP and SST are less sensitive to. B) Being geographically fixed, the SOI and NINO 3.4 indices fail to account for ENSO's seasonal cycle, the loading structures change in accordance w/ the time of the year and even more so wrt SLP, the MEI which uses EOF analysis is able to capture alterations in the structure of the SST and SLP fields with respect to each season and is thus again capturing more variability that's often lost in other indices. C) Geographically stationary indices like the SOI and NINO 3.4 are actually derived from the same EOFs that are used to calculate the MEI, the NINO 3.4 index is among the most popular of the past few decades and was developed by Anthony Barnston in 1997 from EOF analysis of tropical Pacific SSTs, while if EOF analysis was performed for SLP, the SOI generally occurs in the highest loadings D) Geographically fixed indices fail to capture variance outside their very restrictive domains, while in this case EOF analysis in a nutshell compares the structure of the entire field over a large area to the stereotypical ENSO structure for that time of the year... I've already created a few MEI indices w/ ERA-20CM, NCEP-NCAR that make several adjustments to the original MEI, and am still working on an ensemble-based index that will use even more adjustments and stringent quality control to make an extremely powerful MEI index that's nearly available in real-time and goes back as far as possible in the observational record.
Click to expand...

SOI: I think that I'm cautious about how I use the SOI. I don't usually make blanket statements. Instead, I mainly use it to adjust the odds for whatever ENSO phase in my mind up or down. For example, I feel that having a -9 in June increases the chance for El Niño this year based on historical SOI patterns. I didn't say it alone means anything close to definite Niño. Similarly, if July ends up with a +SOI, I'd probably dial back Niño chances somewhat from my current thinking of a very good chance, which is based on the -9 June SOI in combination with evolution of 3.4 SST anomalies since January.
--------------------------

TAO: Interesting info from you suggesting a warm bias of TAO especially during neutral and La Niña. I was unaware of this. I'll need to keep this in mind though I'll counter it by saying this: TAO has been close in recent weeks to what the NOAA weekly 3.4 SST anomalies have shown. Also, Levi's have been 0.1 to 0.2 C cooler in recent weeks fwiw.

OTOH, I agree with you about heavy interpolation in areas between TAO buoys often being a big error source since there aren't that many buoys. So, I do share your concern here. But I don't think that makes TAO anything close to useless and I like to use it more for trends than anything else despite my often trying to estimate the 3.4 anomaly it is suggesting. It has clearly been trending warmer over the last week or so as well as it having been closer to the weeklies than Levi's number the last few weeks.
------------------

MEI: Since you're saying you're a big fan of the MEI and since it has already gone over +1.5 (at least high end moderate territory), why aren't you giving higher chances for El Niño?
 
Speaking of the SOI, whereas it may go negative for a few days shortly, the Tahiti SLPs are shown to rise to solidly above normal for a few days (1017+?) afterward and thus favors another period of solid +SOIs despite Darwin then rising to near 1014 to possibly to as much as near 1015.

I continue to notice a high SLP bias for the GFS at both locations.

We're now getting pretty far into July without a suggestion by model consensus of anywhere near the -9 of June for July absent a sudden -SOI change in the modeling or a dramatic change to strong -SOIs the last week of July. In fact, the chances for a mildly +SOI July are slowly growing right now imo.
 
Last edited:
GaWx said:
Speaking of the SOI, whereas it may go negative for a few days shortly, the Tahiti SLPs are shown to rise to solidly above normal for a few days (1017+?) afterward and thus favors another period of solid +SOIs despite Darwin then rising to near 1014 to possibly to as much as near 1015.

I continue to notice a high SLP bias for the GFS at both locations.

We're now getting pretty far into July without a suggestion by model consensus of anywhere near the -9 of June for July absent a sudden -SOI change in the modeling or a dramatic change to strong -SOIs the last week of July. In fact, the chances for a mildly +SOI July are slowly growing right now imo.
Click to expand...

So you would then dial back your thoughts on El Niño coming if July'a SOI is positive? Is this correct? I'm trying my best to follow you and Webber in your debate with one another.


Sent from my iPhone using Tapatalk
 
whatalife said:
So you would then dial back your thoughts on El Niño coming if July'a SOI is positive? Is this correct? I'm trying my best to follow you and Webber in your debate with one another.
Click to expand...

Yes, somewhat from what I currently think is a very good chance though likely still remaining in the good chance category as long as SST anomalies remain near where they are now. A solid June-July -SOI in combination with the current SST anomalies already being within weak El Nino territory would have increased the chances even further from that "very good" chance. This process of assessing chances is a continual process.
 
Last edited:
Storm5 said:
Sunday afternoon laugh ......ready????

JB is using 76-77 as an analog for the upcoming winter


Sent from my iPhone using Tapatalk
Click to expand...
You ought to get him for a 2nd interview to talk about this winter. ;)

The idea about a DECENT shot at a cold SE winter should we actually get a weak to low end moderate El Nino winter is actually valid to me. However, JB always seems to go out of his way to go cold in the E US with high chances. So, when there is a valid reason for him to just consider going cold, you have the crying wolf syndrome. Furthermore, he usually picks some of the coldest analogs amongst the choices he can make without mentioning the not so cold. 1976-7 is THE coldest winter on record for much of the SE US for those who don't know.
 
pcbjr said:
Dante's 7th Circle, the 3rd ring - look it up ...
and thank you, JB ....
Click to expand...
I went down to the mountain, I was drinking some wine,
Looked up in the heavens Lord I saw a mighty sign,
Writt'n fire across the heaven, plain as black and white;
Get prepared, there's gonna be a party tonight.
Raining fire across the heavens
Just as plain as black and white
Get prepared ....
 
Last edited:
GaWx said:
^ Here are some quotes regarding Mike Ventrice's AEI:

1. This 1st one is from a usually good quality poster: "I think Mike Ventrice's index might be too focused on the tropical Pacific particularly rainfall patterns between the Maritime and the central Pacific, though to be fair I'm not certain what goes into his index."

2. "I have never been impressed with Ventrice, particularly on the ENSO topic."

Response to this one: "As in not impressed with his indices? He works for IBM/TWC. His job is to develop new ways to analyze long range forecasts for their (mostly) energy clients. Some of them work. Some of them have issues."

3. "I wish Ventrice worked on improving key ENSO variables that actually matter. The current variables that we know of are still pretty complicated and mysterious in how and why they work. So if someone with all his resources can invest them in these key indicators, then I would think it would do a lot of good."

My point in showing these is that there is currently a lot of uncertainty regarding the usefulness of the AEI.
Click to expand...

Wait, say what?! Rainfall patterns? Ugh.... It's called an Atmospheric ENSO index for a reason, it doesn't have a whole lot to do w/ precipitation which is exceptionally difficult to measure and similar to the OLR suffers from a warm pool bias. As I said a day or two ago this index was based upon 90-120 day filtered 200 hPa Velocity potential anomalies so that argument is bogus from the get go...

Not impressed? Oh that's funny because the guy has published an extensive amount of work on convectively coupled equatorial waves which are closely linked to ENSO and received his doctorate for his work on convectively coupled Kelvin waves, no big deal (sarc). Your response I certainly agree with....
 
GaWx said:
SOI: I think that I'm cautious about how I use the SOI. I don't usually make blanket statements. Instead, I mainly use it to adjust the odds for whatever ENSO phase in my mind up or down. For example, I feel that having a -9 in June increases the chance for El Niño this year based on historical SOI patterns. I didn't say it alone means anything close to definite Niño. Similarly, if July ends up with a +SOI, I'd probably dial back Niño chances somewhat from my current thinking of a very good chance, which is based on the -9 June SOI in combination with evolution of 3.4 SST anomalies since January.
--------------------------

TAO: Interesting info from you suggesting a warm bias of TAO especially during neutral and La Niña. I was unaware of this. I'll need to keep this in mind though I'll counter it by saying this: TAO has been close in recent weeks to what the NOAA weekly 3.4 SST anomalies have shown. Also, Levi's have been 0.1 to 0.2 C cooler in recent weeks fwiw.

OTOH, I agree with you about heavy interpolation in areas between TAO buoys often being a big error source since there aren't that many buoys. So, I do share your concern here. But I don't think that makes TAO anything close to useless and I like to use it more for trends than anything else despite my often trying to estimate the 3.4 anomaly it is suggesting. It has clearly been trending warmer over the last week or so as well as it having been closer to the weeklies than Levi's number the last few weeks.
------------------

MEI: Since you're saying you're a big fan of the MEI and since it has already gone over +1.5 (at least high end moderate territory), why aren't you giving higher chances for El Niño?
Click to expand...

I'm not giving higher chances for an El Nino because there are still a lot of conflicting signals atm, most climate models trended in the wrong direction for a NINO this past month, the easterly trade winds have been stronger than normal since May, the upper level circulation over the eastern Pacific-Atlantic sector looks more like a cool-biased ENSO event than a NINO, although the southern hemisphere seems to be supportive, and historical precedence of all strong-super NINOs does not support the development of another El Nino event within 2 years after the termination of a strong-super NINO... On the other hand, the current easterly QBO regime favors on equatorial convection and given how close the background state in general already is to an El Nino, it's hard to ignore the possibility of an event oncoming, but I'm really not too impressed at least just yet. Not to mention even if one develops w/ an easterly QBO, this certainly doesnt automatically mean or even just likely favor a colder than normal winter in the SE US...
 
Surprisingly to me based on TAO trends last week, today's release (which covers last calendar week) cooled from +0.7 to +0.6. So, this might be a good example of Eric's concerns about the heavy interpolation between buoys there leading to misleading graphics since there are not many buoys as well as a warm bias. OTOH, Levi's graph averaged over last week suggested +0.5. So, the +0.6 is still +0.1 warmer than Levi's suggested #.
 
Very robust easterly trade wind burst incoming over the dateline later this month according to the EPS, definitely going to be a non-negligible setback to getting an El Nino this fall/winter... Not to mention (once again), the easterly trades have already been above normal for the last 2-2.5 months...
Screen Shot 2017-07-10 at 7.33.29 PM.png
 
^This is consistent with modeling out 2 weeks not looking anything like June SOIwise right now. Other than a few days of -SOIs (next couple of days probably), I still see no solid -SOI string. So, indeed, this may lead to some cooling back at least temporarily as we go through July. Tahiti SLPs look higher than average over the next 2 weeks overall I think.
 
Last edited:
whatalife said:
There goes winter. Larry and Webber agreeing


Sent from my iPhone using Tapatalk
Click to expand...
Yin and Yang
Two complementary principles of Chinese philosophy: Yin is negative, dark, and feminine, Yang positive, bright, and masculine. Their interaction is thought to maintain the harmony of the universe and to influence everything within it ... :eek:
 
pcbjr said:
Yin and Yang
Two complementary principles of Chinese philosophy: Yin is negative, dark, and feminine, Yang positive, bright, and masculine. Their interaction is thought to maintain the harmony of the universe and to influence everything within it ... :eek:
Click to expand...

But we at lest have JB to pull us through......


Sent from my iPhone using Tapatalk
 
You must log in or register to reply here.
Back
Top