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Darvince

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2019 ENSO
« on: January 07, 2019, 06:52:08 AM »
Note that it's 2019, and a new thread could be made.

Please include a long record of ENSO in the opening post.
Trimonthly ONI since 1950:
https://ggweather.com/enso/oni.htm


And seeing as all US government climate websites are currently unavailable, here is this archived page from December 17th last year: http://web.archive.org/web/20181217235025/www.esrl.noaa.gov/psd/enso/

And the current 30-day moving average SOI from the BoM:

Tor Bejnar

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Re: 2019 ENSO
« Reply #1 on: January 07, 2019, 03:05:37 PM »
Although Australia's Bureau of Meteorology is not currently on lock out...


Climate Model Summary for January to May 2019

Issued 17 December 2018 Updated 18 December 2018 Next issue 16 January 2019

Models maintain El Niño thresholds for the ocean, but atmosphere yet to respond
Quote
Sea surface temperatures (SSTs) in the tropical Pacific Ocean have been at or above El Niño thresholds over the past two months. However, atmospheric indicators of El Niño remain neutral, indicating the ocean and atmosphere are not yet coupled (i.e. not reinforcing each other to help sustain the El Niño state).

Five of eight model outlooks suggest El Niño levels will be maintained through to May 2018, while the other three forecast SSTs in the neutral range. It must be noted that model accuracy forecasting through the autumn months is lower than at other times of the year.
Other reports coming out tomorrow (Jan. 8 )
« Last Edit: January 09, 2019, 05:20:14 PM by Tor Bejnar »
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Sigmetnow

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Re: 2019 ENSO
« Reply #2 on: January 09, 2019, 05:17:20 PM »
Quote
Models maintain El Niño thresholds for the ocean, but atmosphere yet to respond

How unusual is this?
People who say it cannot be done should not interrupt those who are doing it.

Tor Bejnar

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Re: 2019 ENSO
« Reply #3 on: January 09, 2019, 05:26:04 PM »
I cannot answer your question, Sigmetnow, but a report released yesterday talks about the issues involved:
Quote
Some recent cooling in the tropical Pacific Ocean
 
Tropical Pacific Ocean surface waters have returned to ENSO-neutral temperatures after exceeding El Niño levels in November and early December. The Bureau's ENSO Outlook remains at El Niño ALERT.

While waters at and beneath the surface of the tropical Pacific have been warmer than average since mid-2018, atmospheric indicators of ENSO such as cloudiness, trade winds and the Southern Oscillation Index (SOI) have not responded and have mostly remained neutral. For an El Niño to become established, the atmosphere needs to reinforce and respond to the warmer waters at the ocean's surface. This reinforcement is what allows the widespread global effects on weather and climate to occur.

The recent cooling of tropical Pacific waters may partly reflect the movement of the Madden–Julian Oscillation (MJO), which has recently encouraged stronger trade winds over the tropical Pacific. However, the MJO is moving east, weakening the trade winds once again, which may allow the ocean surface to warm again.

Most models indicate sea surface temperatures in the tropical Pacific are likely to remain near El Niño levels at least until early autumn 2019. Models typically have less skill when forecasting through autumn compared with other seasons. If sea surface temperatures do maintain their anomalous warmth through summer, it increases the chance of El Niño emerging in 2019.
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Pmt111500

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Re: 2019 ENSO
« Reply #4 on: January 09, 2019, 05:50:32 PM »

Trimonthly ONI since 1950:
https://ggweather.com/enso/oni.htm



Thank you !  Looks like the 60š were a lot less in La Nina than I remembered.
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Rodius

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Re: 2019 ENSO
« Reply #5 on: January 15, 2019, 02:42:42 AM »
Down to +2.0

Comment from the site.
The 30-day Southern Oscillation Index (SOI) to 6 January was +6.2, and the 90-day SOI was +4.0. The SOI has remained within the neutral ENSO range since early September. There have been fluctuations over recent recent weeks, however during the southern hemisphere summer the SOI is more volatile due to the passage of tropical storms and should therefore be viewed with caution.

Tor Bejnar

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Re: 2019 ENSO
« Reply #6 on: January 15, 2019, 06:13:40 PM »
From NOAA: updated January 14, 2019 (despite the government closure)
http://www.cpc.ncep.noaa.gov/products/CDB/Forecast/figf4.shtml
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wolfpack513

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Re: 2019 ENSO
« Reply #7 on: January 19, 2019, 03:24:08 AM »
New downwelling kelvin wave near the dateline.  A response to the relaxed trades & westerly winds in that area the last 30 days. 

gerontocrat

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Re: 2019 ENSO
« Reply #8 on: January 19, 2019, 11:58:09 AM »
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Rodius

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Re: 2019 ENSO
« Reply #9 on: January 30, 2019, 10:36:13 PM »
Sittign on -1.3


From the site:
ENSO Outlook lowered to El Niño WATCH
Recent observations and climate model outlooks suggest the immediate risk of El Niño has passed.

However, there remains an increased likelihood that El Niño will develop later in 2019. The Bureau's ENSO Outlook has therefore moved to El Niño WATCH, meaning there is approximately a 50% chance of El Niño developing during the southern hemisphere autumn or winter.

Tropical Pacific sea surface and sub-surface temperatures remain warmer than average, but since late 2018 they have cooled from El Niño-like values towards ENSO-neutral values. Atmospheric indicators such as cloudiness, trade winds and the Southern Oscillation Index all continue to generally remain within the ENSO-neutral range.

While most climate models indicate ENSO-neutral conditions for the immediate future, the current ocean warmth and likelihood of ongoing warmer than average conditions mean the risk of El Niño remains. Three of eight models suggest that El Niño may establish by mid-2019.

Pmt111500

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Re: 2019 ENSO
« Reply #10 on: February 06, 2019, 12:25:17 PM »
Yep, possible El Nino coming up later this year, the 2.4 years period some models suggest has almost passed since the last notable one. 50-50 is a fine prediction!!
« Last Edit: February 06, 2019, 12:38:27 PM by Pmt111500 »
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wolfpack513

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Re: 2019 ENSO
« Reply #11 on: February 07, 2019, 05:53:54 AM »
Major changes underway in the equatorial Pacific.  Near the dateline a strong standing wave has developed.  Strongest forcing yet in this ENSO cycle.  There is also a strengthening subsurface kelvin wave that will have more of an impact on 2019-2020 ENSO cycle. 

wolfpack513

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Re: 2019 ENSO
« Reply #12 on: February 12, 2019, 07:38:02 PM »
Dateline WWB is off the charts the next 5 days coming up.  Interesting to follow the VP anomalies back to early January.  MJO wave passes over dateline around February 1 which triggers the strong standing wave. 

BornFromTheVoid

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Re: 2019 ENSO
« Reply #13 on: February 14, 2019, 06:04:17 PM »
Synopsis: Weak El Niño conditions are present and are expected to continue through the Northern
Hemisphere spring 2019 (~55% chance).

https://twitter.com/NWSCPC/status/1096049726120697856

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.pdf

gerontocrat

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Re: 2019 ENSO
« Reply #14 on: February 14, 2019, 06:39:21 PM »
Synopsis: Weak El Niño conditions are present and are expected to continue through the Northern
Hemisphere spring 2019 (~55% chance).

https://twitter.com/NWSCPC/status/1096049726120697856

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.pdf
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Re: 2019 ENSO
« Reply #15 on: February 15, 2019, 09:26:28 AM »
Australia is still saying their is a 50% chance of an El Nino.
But the USA has called it.
They use different methods to determine one, with Australia having the more difficult criteria.
https://www.usatoday.com/story/news/nation/2019/02/14/el-nino-natural-warming-ocean-water-forms-climate-scientists/2868209002/

Sitting on -1.4

wolfpack513

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Re: 2019 ENSO
« Reply #16 on: February 15, 2019, 09:50:48 AM »
For the U.S. (CPC) it’s basic math, this shouldn’t be that surprising.  It’s not going to take much to get 2 more ONIs to complete the 5 ONIs. December and January ERSSTv5 values both came in at +0.8°C.  DJF is a lock and JFM should be easy considering the ongoing off the charts westerly wind burst. 

Rodius

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Re: 2019 ENSO
« Reply #17 on: February 21, 2019, 12:32:43 AM »
Sudden drop to -6.7
-7.0 is El Nino territory.

Comments from the site update:
Tropical Pacific sea surface temperatures have warmed slightly in the past fortnight. In the sub-surface, weak warmth extends down to 175 m depth. Recent weakening of the trade winds in the western Pacific means that further warming of the equatorial Pacific is likely in the coming weeks to months.

Five of eight climate models indicate the central Pacific is likely to reach borderline or weak El Niño levels during autumn, with four models remaining above threshold levels into winter. El Niño predictions made in late summer and early autumn tend to have lower accuracy than predictions made at other times of the year. This means that current forecasts of the ENSO state beyond May should be used with some caution.

oren

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Re: 2019 ENSO
« Reply #18 on: February 21, 2019, 02:22:19 AM »
Thanks for the SOI updates Rodius.

Rodius

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Re: 2019 ENSO
« Reply #19 on: March 01, 2019, 12:58:04 PM »
Now at -11.6
When will the El Nino be called?

magnamentis

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Re: 2019 ENSO
« Reply #20 on: March 02, 2019, 12:09:42 AM »
Now at -11.6
When will the El Nino be called?

i've been reading in several places that it's called while i dunno whether there is single entity that counts.

Rodius

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Re: 2019 ENSO
« Reply #21 on: March 02, 2019, 12:18:53 AM »
Now at -11.6
When will the El Nino be called?

i've been reading in several places that it's called while i dunno whether there is single entity that counts.

The USA has called it.
Australia has a more complex method and they are sitting on Watch with the next review coming on March 5th.
While El Nino is being talked about, Australia seems to be the Gold Standard. Wait for March 5th.

bbr2314

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Re: 2019 ENSO
« Reply #22 on: March 02, 2019, 12:36:42 AM »
My 2 cents = mod-strong Nino impending for 19-20

magnamentis

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Re: 2019 ENSO
« Reply #23 on: March 02, 2019, 01:02:38 AM »
Now at -11.6
When will the El Nino be called?

i've been reading in several places that it's called while i dunno whether there is single entity that counts.

thanks for the heads-up, i'm not very privy with those details, always good to get a better idea about what's going on and who says and is what ;)

The USA has called it.
Australia has a more complex method and they are sitting on Watch with the next review coming on March 5th.
While El Nino is being talked about, Australia seems to be the Gold Standard. Wait for March 5th.

Rodius

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Re: 2019 ENSO
« Reply #24 on: March 02, 2019, 02:30:58 AM »
My 2 cents = mod-strong Nino impending for 19-20

Australian BOM is saying 50% chance of El Nino but that was 2 or 3 weeks ago. Looking at it now it seems more likely to be an El Nino BUT BOM also states that in Autumn there can be wild swings in the indicators.
Also of note, they say that should one happen (likely now) it would be mild to moderate.

If it ends up strong, I personally will worry because Australia just recorded the hottest summer on record country wide (+2.4C) with neutral conditions.
El Nino increases those rises.
The last record over summer was during a strong El Nino.

Anyway, while I hope it isnt strong, it is only a matter of time before one comes, and when it does, the Arctic melt season could be rather bad.

gerontocrat

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Re: 2019 ENSO
« Reply #25 on: March 15, 2019, 10:14:02 AM »
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml
Quote
CLIMATE PREDICTION CENTER/NCEP/NWS
and the International Research Institute for Climate and Society
14 March 2019

ENSO Alert System Status: El Niño Advisory

Synopsis:  Weak El Nino conditions are likely to continue through the Northern Hemisphere spring 2019 (~80% chance) and summer (~60% chance).

El Niño conditions strengthened during February 2019, as above-average sea surface temperatures (SSTs) increased across the equatorial Pacific Ocean [Fig. 1] and the associated atmospheric anomalies became increasingly well-defined. The SST index values in the Niño3, Niño3.4 and Niño4 regions all increased during February, with the latest weekly values near +1°C in each region [Fig. 2]. The anomalous upper-ocean heat content (averaged across 180°-100°W) increased appreciably during February [Fig. 3], due to an increase in above-average temperatures at depth in association with a downwelling equatorial oceanic Kelvin wave [Fig. 4]. Enhanced equatorial convection prevailed near the Date Line, while suppressed convection was observed over Indonesia [Fig. 5]. Low-level wind anomalies were westerly in the central Pacific Ocean, while upper-level wind anomalies were mostly westerly over the far western and far eastern Pacific. The equatorial and traditional Southern Oscillation Index values were both negative (-1.4 standard deviations). Overall, these features are consistent with weak El Niño conditions.

The majority of models in the IRI/CPC plume predict a Niño 3.4 index of +0.5°C or greater through the Northern Hemisphere early autumn 2019 [Fig. 6]. Given the recent downwelling Kelvin wave, and the increase in both the SSTs and subsurface ocean temperatures, most forecasters expect positive SST anomalies to persist across the central and eastern Pacific for at least the next several months. During that time, forecasters predict the SST anomalies in the Niño 3.4 region to remain between +0.5°C and +1.0°C, indicating weak El Niño conditions. However, because forecasts made during spring tend to be less accurate, the predicted chance that El Niño will persist beyond summer is currently about 50%. In summary, weak El Niño conditions are likely to continue through the Northern Hemisphere spring 2019 (~80% chance) and summer (~60% chance); click CPC/IRI consensus forecast for the chance of each outcome for each 3-month period.

This discussion is a consolidated effort of the National Oceanic and Atmospheric Administration (NOAA), NOAA's National Weather Service, and their funded institutions. Oceanic and atmospheric conditions are updated weekly on the Climate Prediction Center web site (El Niño/La Niña Current Conditions and Expert Discussions). Forecasts are also updated monthly in the Forecast Forum of CPCs Climate Diagnostics Bulletin. Additional perspectives and analysis are also available in an ENSO blog. The next ENSO Diagnostics Discussion is scheduled for 11 April 2019.

To receive an e-mail notification when the monthly ENSO Diagnostic Discussions are released, please send an e-mail message to: ncep.list.enso-update@noaa.gov.

 
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Rodius

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Re: 2019 ENSO
« Reply #26 on: March 15, 2019, 12:54:49 PM »
Sitting on -15 and been there for a short while.

Australia still hasnt called it.... next update is March 19.
Surely they will call it now?

Rodius

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Re: 2019 ENSO
« Reply #27 on: March 20, 2019, 05:53:13 AM »
Sitting on -12.8
They are saying the El Nino is on Alert

From BOM
Southern Oscillation Index
The 30-day Southern Oscillation Index (SOI) has been steady over the past two weeks, remaining within El Niño territory. The SOI value for the 30 days to 17 March was −13.3. However, the 90-day SOI is still well within neutral territory at −5.1.

While values of the 30-day SOI have been strongly negative for almost a month, SOI values during the northern Australian wet season can be volatile, and should therefore be viewed with caution. This is because the passage of tropical systems near Darwin and Tahiti can affect atmospheric pressure at these locations, and hence the value of the SOI.

Rodius

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Re: 2019 ENSO
« Reply #28 on: April 02, 2019, 12:58:42 PM »
Latest Update
-7.4
Outlook: El Nino Alert

From BOM
The 30-day Southern Oscillation Index (SOI) has been steady over the past two weeks, remaining close to the El Niño threshold value. The SOI value for the 30 days to 31 March was −7.4. The 90-day SOI value remains within neutral territory at −6.5, but has generally been only a little below the threshold value over the past fortnight.

The passage of tropical systems near Darwin and Tahiti can affect atmospheric pressure at these locations, meaning that SOI values during the northern Australian wet season can be volatile, and should therefore be viewed with caution.

Sustained negative values of the SOI below −7 typically indicate El Niño while sustained positive values above +7 typically indicate La Niña. Values between +7 and −7 generally indicate neutral conditions.

El Niño ALERT – tropical Pacific Ocean warm but little atmospheric response
The Bureau's ENSO Outlook remains at El Niño ALERT. This means the chance of El Niño developing in 2019 is approximately 70%; around triple the normal likelihood.

Tropical Pacific sea surface temperatures have remained close to El Niño thresholds for the past five weeks. The atmosphere has responded to the surface warmth at times, but is yet to show a consistent El Niño-like response. For example, trade winds have varied between weaker-than-average and average strength.

Most international climate models predict tropical Pacific Ocean sea surface temperatures will remain at El Niño levels at least to mid-year. This would increase the likelihood of the tropical Pacific atmosphere and ocean reinforcing each other, and developing into a full El Niño, with the resultant changes in Australian and global weather patterns. Predictions made at this time of year have lower accuracy than those made in winter or spring and should be used with some caution.

oren

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Re: 2019 ENSO
« Reply #29 on: April 02, 2019, 02:30:09 PM »
Thanks for these periodic updates Rodius.

Rodius

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Re: 2019 ENSO
« Reply #30 on: April 03, 2019, 01:59:46 AM »
Thanks for these periodic updates Rodius.

It only takes ten minutes to do, and given how much I am learning and how much time others put into this site, this is my small contribution to the cause.
One thing I am digging into for my own learning re ENSO is to get explanations for the different criteria other countries have for ENSO and maybe delve into the various effects ENSO has on different parts of the world.
That is a bit bigger to do and I am not a scientist so as I am working on that, I need to ensure I have the information correct.... but when I am satisfied it is most right, I will post the information on here for others to read and discuss.

ENSO is important in terms of climate change. It will being affecting the Arctic this year, and given the melting this past two weeks, ENSO might be a nail for a very low minimum this year.

gerontocrat

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Re: 2019 ENSO
« Reply #31 on: April 13, 2019, 11:33:51 AM »
The US view on the 2019 El Nino - "A weak El Nino is likely to continue"

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml
Quote
EL NIÑO/SOUTHERN OSCILLATION (ENSO)
DIAGNOSTIC DISCUSSION
issued by
CLIMATE PREDICTION CENTER/NCEP/NWS
and the International Research Institute for Climate and Society
11 April 2019

ENSO Alert System Status: El Niño Advisory

 
Synopsis:  A weak El Nino is likely to continue through the Northern Hemisphere summer 2019 (65% chance) and possibly fall (50-55% chance).

El Niño continued during March 2019, as above-average sea surface temperatures (SSTs) persisted across the equatorial Pacific Ocean [Fig. 1]. The latest weekly values of the Niño3 and Niño4 indices were +0.8°C, while the Niño3.4 value was +0.9°C [Fig. 2]. The anomalous upper-ocean heat content (averaged across 180°-100°W) decreased during March but remained well above average [Fig. 3], as the above-average temperatures at depth peaked in early March in association with a downwelling equatorial oceanic Kelvin wave [Fig. 4]. Enhanced equatorial convection was observed near the Date Line and in the western Pacific, while suppressed convection prevailed over western Indonesia [Fig. 5]. Low-level wind anomalies were westerly in the western Pacific Ocean during March. Meanwhile, upper-level winds were mostly near average. The equatorial and traditional Southern Oscillation Index values were negative. Overall, these features are consistent with a weak El Niño.

The majority of models in the IRI/CPC plume predict a Niño 3.4 index of +0.5°C or greater through the remainder of 2019 [Fig. 6]. Most forecasters expect SST anomalies in the Niño 3.4 region to remain between +0.5°C and +1.0°C for at least the next several seasons, indicating a weak El Niño. However, because forecasts made during spring tend to be less accurate, the predicted chance that El Niño will persist through fall is currently 50-55%. In summary, a weak El Niño is likely to continue through the Northern Hemisphere summer 2019 (65% chance) and possibly fall (50-55% chance; click CPC/IRI consensus forecast for the chance of each outcome for each 3-month period).

This discussion is a consolidated effort of the National Oceanic and Atmospheric Administration (NOAA), NOAA's National Weather Service, and their funded institutions. Oceanic and atmospheric conditions are updated weekly on the Climate Prediction Center web site (El Niño/La Niña Current Conditions and Expert Discussions). Forecasts are also updated monthly in the Forecast Forum of CPCs Climate Diagnostics Bulletin. Additional perspectives and analysis are also available in an ENSO blog. The next ENSO Diagnostics Discussion is scheduled for 9 May 2019.

To receive an e-mail notification when the monthly ENSO Diagnostic Discussions are released, please send an e-mail message to: ncep.list.enso-update@noaa.gov.

 
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Re: 2019 ENSO
« Reply #32 on: April 16, 2019, 10:09:31 AM »
From Australia BOM
Still have the setting on El Nino Alert

Southern Oscillation Index
The 30-day Southern Oscillation Index (SOI) has eased back to more neutral levels over the past fortnight. The SOI for the 30 days ending 14 April was −2.0, with the 90-day average −5.8.

As the northern Australian wet season nears it end, the SOI will become less volatile, and will be expected to better reflect the climatic conditions. During the wet season, the passage of tropical systems near Darwin and Tahiti can affect atmospheric pressure at these locations, meaning that SOI values during the northern Australian wet season can be erratic, and should therefore be viewed with caution.

Sustained negative values of the SOI below −7 typically indicate El Niño while sustained positive values above +7 typically indicate La Niña. Values between +7 and −7 generally indicate neutral conditions.

Rodius

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Re: 2019 ENSO
« Reply #33 on: April 30, 2019, 10:57:31 AM »
The 30-day Southern Oscillation Index (SOI) remains neutral. The SOI value for the 30 days to 28 April was −3.0, while the 90-day average was −7.9.

As the northern Australian wet season nears its end, the SOI will become less volatile, and will be expected to better reflect climatic conditions. During the wet season, the passage of tropical systems near Darwin and Tahiti can affect atmospheric pressure at these locations, meaning that SOI values during the northern Australian wet season can be erratic, and should therefore be viewed with caution.

Sustained negative values of the SOI below −7 typically indicate El Niño while sustained positive values above +7 typically indicate La Niña. Values between +7 and −7 generally indicate neutral conditions.

Outlooks indicate short-lived El Niño likely
The Bureau's ENSO Outlook remains at El Niño ALERT. This means the chance of El Niño developing in 2019 is approximately 70%. Climate models indicate that if El Niño does develop it is likely to be short-lived.

Although the surface of the tropical Pacific Ocean remains warmer than average, water below the surface of the ocean has been gradually cooling. A cooling of water at depth can lead to a cooling of the ocean surface, which may reduce the length of an event if one develops. Most climate models indicate surface warmth in the Pacific Ocean will remain at El Niño-like levels at least through May. The longer the ocean surface warmth remains, the more likely it is that the atmosphere will respond, and El Niño will develop.

If El Niño does develop in May, it's likely to be short lived, with most models indicating that the ocean will likely cool through winter and spring. Four of the eight surveyed models return to neutral by September, and the other four indicate weak El Niño levels.

wolfpack513

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Re: 2019 ENSO
« Reply #34 on: April 30, 2019, 05:13:35 PM »
SOI is great and can be used in analogs and forecasts but it's also an observation just like ONI. 

SOI likely went neutral in April due to interference from Kelvin/MJO wave but the El Niño standing wave still remains. 

A strong WWB is just getting started and will migrate east of the dateline in the next 2 weeks.  This will have the greatest impact on the upcoming ENSO cycle and whether the current El Niño fades or its a 2-cycle/year event.

Rodius

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Re: 2019 ENSO
« Reply #35 on: May 15, 2019, 11:07:46 AM »
From Aust BOM

ENSO Outlook decreased to El Niño WATCH; positive IOD possible
Indicators have been close to El Niño thresholds over the past several months, but signs have emerged of a weakening of these patterns. As a result, the Bureau's ENSO Outlook has been downgraded to El Niño WATCH. This means the chance of El Niño developing in 2019 is approximately 50%, which is still double the normal likelihood.

While sea surface temperatures in the tropical Pacific Ocean remain close to El Niño levels, water beneath the surface has slowly cooled over the past few months. Atmospheric indicators such as the Southern Oscillation Index (SOI) and cloudiness near the Date Line have generally remained in the neutral range, despite short-term El Niño-like SOI values in the last fortnight.

International models surveyed by the Bureau indicate that sea surface temperatures in the tropical Pacific are likely to remain near El Niño thresholds until mid-winter, before cooling in late winter to spring. By August, two of the eight models are clearly at El Niño levels, with another two near El Niño thresholds.

The 30-day Southern Oscillation Index (SOI) remains neutral. The SOI value for the 30 days to 12 May was −6.2, while the 90-day average was −8.3.

Sustained negative values of the SOI below −7 typically indicate El Niño while sustained positive values above +7 typically indicate La Niña. Values between +7 and −7 generally indicate neutral conditions.

gerontocrat

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Re: 2019 ENSO
« Reply #36 on: May 15, 2019, 11:25:10 AM »
The USA use a slightly different definition of what constitutes an El Nino.  forgot all about the monthly update from https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

but here it is...
Quote
9 May 2019  ENSO Alert System Status: El Niño Advisory

Synopsis:  El Niño is likely to continue through the Northern Hemisphere summer 2019 (70% chance) and fall (55-60% chance).

During April, above-average sea surface temperatures (SSTs) persisted across most of the equatorial Pacific Ocean [Fig. 1], reflecting the ongoing El Niño. All of the latest weekly Niño indices were near +0.8°C, except for Niño-1+2 index, which was at +0.3°C [Fig. 2]. While surface indicators were relatively unchanged during the month, the anomalous upper-ocean subsurface temperatures (averaged across 180°-100°W) decreased through April [Fig. 3]. Subsurface temperature anomalies remained positive close to the surface across the equatorial Pacific Ocean, but were increasingly negative at depth [Fig. 4]. Suppressed tropical convection was evident near Indonesia and enhanced convection continued near the Date Line, though weaker compared to the last two months [Fig. 5]. Low-level wind anomalies were weak over the tropical Pacific Ocean, with easterly anomalies evident over the western Pacific. Upper-level wind anomalies were easterly over the western Pacific and westerly over most of the eastern Pacific. Overall, oceanic and atmospheric conditions were consistent with El Niño.

The majority of models in the IRI/CPC plume predict El Niño to continue through 2019, with SST anomalies in the Niño-3.4 region clustering between +0.5°C and +1.0°C [Fig. 6]. However, model predictions made during the spring tend to be less accurate relative to the rest of the year, so uncertainty remains whether this outcome will occur. In the shorter term, a recent increase in westerly wind anomalies over the west-central Pacific Ocean portends the possible development of another downwelling oceanic Kelvin wave, which could build up the above-average subsurface temperatures needed for El Niño to persist. In summary, El Niño is likely to continue through the Northern Hemisphere summer 2019 (70% chance) and fall (55-60% chance; click CPC/IRI consensus forecast for the chance of each outcome for each 3-month period).
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Rodius

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Re: 2019 ENSO
« Reply #37 on: May 16, 2019, 04:23:06 AM »
I am not sure if this question belongs here or in stupid questions.... but I will start here.

The US and Australia have different definitions for El Nino.
Why dont they have an agreed upon definition? To me, that would make more sense than one side saying yes and the other side saying no. And for clarity of definition, it makes sense too.

And, is the difference of definition more to do with El Nino having more effects on the North America at lower levels than it does on Australia?

And while I am at it, when is the US going to start using the metric system? (this is my hint that the US should use the Australian definition :) )

gerontocrat

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Re: 2019 ENSO
« Reply #38 on: May 17, 2019, 05:58:15 PM »
To add to the general confusion.

Is this El Nino a "Modoki" El Nino or a conventional El Nino. Bangladesh wants to know.

https://www.dhakatribune.com/opinion/op-ed/2019/05/04/further-complicating-matters
Quote
Further complicating matters
Tens of thousands of Rohingya refugees in camps across Bangladesh are at imminent risk of El Niño-related drought this year.

Currently, there is a 60-70% chance of an El Niño developing by summer this year. Initially, it looked like Warm Pool El Niño (or El Niño-Modoki), but it is currently changing to conventional El Niño. This El Niño could have an enormous global impact and may be even more severe than previous occurrences. This can cause lower than normal rainfall, warmer than normal temperatures, higher possibility of drought, and higher than normal cyclonic activities for the next six to eight months in Bangladesh, particularly in the Chittagong and Cox’s Bazar area.

ps: Somewhere I read a suggestion that a Modoki El Nino event is sometimes followed a year or two later by a very strong El Nino ?

pps: "El Niño "Modoki" (Japanese for "a similar but different thing") or a Central Pacific El Niño, wherein enhanced SSTs and rainfall occur near the dateline and not near the coast of Peru." Phys.org
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Re: 2019 ENSO
« Reply #39 on: May 18, 2019, 12:35:51 AM »
The US is adopting the metric system. :)  Unfortunately it is occurring at a glacial  snails pace. :(  I think it has more to do with globalization more than any effort to change from here.

Pmt111500

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Re: 2019 ENSO
« Reply #40 on: May 18, 2019, 05:35:58 AM »
"El Niño "Modoki" (Japanese for "a similar but different thing") or a Central Pacific El Niño, wherein enhanced SSTs and rainfall occur near the dateline and not near the coast of Peru." Phys.org
Ah, this might explain the continued high CO2 values of Mauna Loa.  I haven't checked the anomalies in central Pacific and don't remember the exact definition from the scientific article by the japanese scholars who coined the term. Anyway the anomaly in Modoki locates west of the regular Nino areas so we should add areas 5-8 to the mappes depicting warm anomalies in tropical Pacific. (Oops, it was rather "split the areas 4 and 3" to better define this one.)

I believe the mechanism is pretty much the same in both of them but sometimes the pulse of undercurrent warm water surfaces early. Modoki could possibly be called interrupted or premature El Nino. I don't remember how it dissipates but I guess some of the heat stays in place and gets swept by with the next El Nino so this might be leading to a big one. Development of Modoki instead of high +enso might have had something to do with the seasons so the summer months had more of them, but the dataset wasn't too large. O, how we forget.
« Last Edit: May 18, 2019, 05:46:37 AM by Pmt111500 »
Cooling the outside by heat pump.

Rodius

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Re: 2019 ENSO
« Reply #41 on: May 29, 2019, 06:50:01 AM »
Here is the update from Aust. BOM

The 30-day Southern Oscillation Index (SOI) remains neutral. The SOI value for the 30 days to 26 May was −7.4, while the 90-day average has risen to −5.3.

The Pacific Ocean and overlying atmosphere remain close to El Niño thresholds, so the ENSO Outlook remains at El Niño WATCH. Models indicate the tropical Pacific Ocean will ease away from El Niño levels, becoming neutral during winter. The Indian Ocean is expected to become the dominant influence on Australian climate, with models predicting a positive phase of the Indian Ocean Dipole (IOD) is likely to develop in the coming months.

An active phase of the Madden-Julian Oscillation in the last fortnight weakened the trade winds and brought a small rise in sea surface temperatures (SSTs) in the central and western tropical Pacific Ocean and a drop in the Southern Oscillation Index (SOI). This has sustained the El Niño-like pattern in the Pacific. While a prolonged weakening of the trade winds could elevate El Niño chances once again, the majority of surveyed models suggest the tropical Pacific will cool to neutral levels during winter.

In the Indian Ocean, further warming off the horn of Africa has meant that the IOD index exceeded the positive threshold value this week. All but one of the models surveyed suggest positive IOD levels will be maintained throughout winter. To be considered an event, these values would need to be sustained for at least two months. A positive IOD often results in below average winter–spring rainfall over southern and central Australia.

SIDE NOTE: Australia, already in drought, looks like having a dry winter, spring and summer. We are already importing wheat because of crops failures.

Rodius

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Re: 2019 ENSO
« Reply #42 on: June 15, 2019, 11:11:27 AM »
From BOM

The 30-day Southern Oscillation Index (SOI) has seen recent values fall to El Niño levels, but in the longer-term, values remain neutral. The SOI for the 30 days ending 9 June is −9.6, with the 90-day average −6.2.

Sustained negative values of the SOI below −7 typically indicate El Niño while sustained positive values above +7 typically indicate La Niña. Values between +7 and −7 generally indicate neutral conditions.

The tropical Pacific Ocean and atmosphere remain near El Niño thresholds, meaning the ENSO Outlook remains at El Niño WATCH. Climate models suggest a gradual shift away from El Niño levels over the coming months. Indian Ocean temperature forecasts, on the other hand, show a positive Indian Ocean Dipole (IOD) through the southern winter, which is likely to be the dominant climate driver for Australia.

A fortnight ago, a pulse of the Madden–Julian Oscillation (MJO) weakened trade winds, which led to some renewed warming at the surface of the tropical Pacific Ocean. However, this MJO pulse has passed, returning trade winds to normal levels. With little warmth in the ocean sub-surface, most climate models suggest the tropical Pacific will cool, shifting away from El Niño thresholds, during winter.

In the Indian Ocean, waters off Sumatra have cooled over the past fortnight, with the IOD index now exceeding positive thresholds for three weeks. All but one of the climate models suggest positive IOD values will persist through winter and into spring. To be considered a positive IOD event, positive thresholds need to be maintained for at least two months.

gerontocrat

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Re: 2019 ENSO
« Reply #43 on: June 15, 2019, 01:26:33 PM »
Forgot to post the NOAA monthly summary at..
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

El Nino persisting but not a big one.

Quote
EL NIÑO/SOUTHERN OSCILLATION (ENSO)
DIAGNOSTIC DISCUSSION
issued by
CLIMATE PREDICTION CENTER/NCEP/NWS
and the International Research Institute for Climate and Society
13 June 2019
 
ENSO Alert System Status: El Niño Advisory
 
Synopsis:  El Niño is predicted to persist through the Northern Hemisphere summer 2019 (66% chance), with lower odds of continuing through the fall and winter (50-55% chance).

During May, El Niño was reflected in the continued presence of above-average sea surface temperatures (SSTs) across most of the equatorial Pacific Ocean [Fig. 1]. The latest weekly ENSO indices indicate the largest positive SST anomalies were within the central Pacific (+1.1°C in Niño-4 and +0.9°C in Niño-3.4) with smaller departures in the Niño-3 and Niño-1+2 regions [Fig. 2]. Upper-ocean subsurface temperatures (averaged across 180°-100°W) were nearly average at the start of May, but positive anomalies increased toward the end of the month in association with a downwelling Kelvin wave [Fig. 3]. Thus, anomalies remained positive at depth in the central equatorial Pacific Ocean, with negative anomalies evident in the eastern Pacific [Fig. 4]. Suppressed tropical convection continued over Indonesia, while weak, enhanced convection persisted near the Date Line [Fig. 5]. Low-level wind anomalies were westerly over the western tropical Pacific Ocean, and upper-level wind anomalies were easterly over the western and east-central Pacific. Overall, oceanic and atmospheric conditions were consistent with El Niño.

The combined averages in the IRI/CPC plume predict El Niño to continue into Northern Hemisphere winter 2019-20, but individual models span ENSO-neutral to El Niño outcomes (generally +0.0°C to +1.0°C; [Fig. 6]). The forecast consensus reflects this uncertainty, with slightly lower chances for El Niño compared to the previous month. Ongoing subseasonal variability within the tropical Pacific contributes to an overall murky picture, but the current downwelling oceanic Kelvin wave should fuel the persistence of El Niño at least in the short-term. In summary, El Niño is predicted to persist through the Northern Hemisphere summer 2019 (66% chance), with lower odds of continuing through the fall and winter (50-55% chance; click CPC/IRI consensus forecast for the chance of each outcome for each 3-month period).

This discussion is a consolidated effort of the National Oceanic and Atmospheric Administration (NOAA), NOAA's National Weather Service, and their funded institutions. Oceanic and atmospheric conditions are updated weekly on the Climate Prediction Center web site (El Niño/La Niña Current Conditions and Expert Discussions). Forecasts are also updated monthly in the Forecast Forum of CPCs Climate Diagnostics Bulletin. Additional perspectives and analysis are also available in an ENSO blog. The next ENSO Diagnostics Discussion is scheduled for 11 July 2019.
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Rodius

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Re: 2019 ENSO
« Reply #44 on: June 29, 2019, 05:20:27 AM »
What BOM says.....
The 30-day Southern Oscillation Index (SOI) has remained near El Niño threshold levels over the past two weeks, while 90-day values have remained neutral. The SOI for the 30 days ending 23 June was −8.7, with the 90-day value −5.6.

Sustained negative values of the SOI below −7 typically indicate El Niño while sustained positive values above +7 typically indicate La Niña. Values between +7 and −7 generally indicate neutral conditions.

The immediate likelihood of El Niño developing has passed, meaning the ENSO Outlook has been reset to INACTIVE. While the possibility of El Niño can't be completely ruled out for 2019, the tropical Pacific Ocean is more likely than not to remain in an ENSO-neutral phase over the coming months. Model outlooks indicate a positive Indian Ocean Dipole is likely to drive Australia's weather for much of the rest of 2019, meaning the likelihood of a drier than average winter–spring remains.

Oceanic and atmospheric indicators are now largely at ENSO-neutral levels. Tropical Pacific sea surface temperatures have cooled over the past fortnight but remain slightly warmer than average. Cloudiness near the Date Line and trade winds have been close to neutral over recent weeks, while the Southern Oscillation Index (SOI) has hovered around El Niño threshold values over the past month. With little anomalous warmth in the ocean sub-surface, most climate models indicate the tropical Pacific will continue shifting further away from El Niño thresholds through the winter.

gerontocrat

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Re: 2019 ENSO
« Reply #45 on: July 12, 2019, 08:20:36 PM »
By the definition used by the Climate Prediction Center of the USA, we are still in a weak El Nino, transitioning to neutral in month or two..

Note the gradually increasing risk of a return to El Nino later in the year

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml
Quote
EL NIÑO/SOUTHERN OSCILLATION (ENSO)
DIAGNOSTIC DISCUSSION
issued by
CLIMATE PREDICTION CENTER/NCEP/NWS
and the International Research Institute for Climate and Society
11 July 2019
 
ENSO Alert System Status: El Niño Advisory

 
Synopsis:  A transition from El Niño to ENSO-neutral is expected in the next month or two, with ENSO-neutral most likely to continue through Northern Hemisphere fall and winter.

During June, El Niño was reflected in the continued presence of above average sea surface temperatures (SSTs) across the central equatorial Pacific Ocean [Fig. 1]. However, SST anomalies across most of the eastern Pacific decreased during the month. The latest weekly ENSO indices were +0.9°C in Niño-4 and +0.6°C in Niño-3.4, with smaller departures in the Niño-3 and Niño-1+2 regions [Fig. 2]. Upper-ocean subsurface temperatures (averaged across 180°-100°W) were above average at the beginning of June, but returned to near average by end of the month [Fig. 3], as anomalously cool waters expanded at depth [Fig. 4]. Weakly suppressed tropical convection continued over Indonesia, while weakly enhanced convection persisted near the Date Line [Fig. 5]. Low-level wind anomalies were near average over the tropical Pacific Ocean, and upper-level wind anomalies were westerly over the far eastern Pacific. The traditional and equatorial Southern Oscillation Indices were slightly negative. Overall, oceanic and atmospheric conditions were consistent with a weakening El Niño.

The latest plume of North American Multi-model Ensemble forecasts of the Niño-3.4 index [Fig. 6] shows a rapid transition toward ENSO-neutral by the late Northern Hemisphere summer, remaining neutral through fall and winter. Due to this model guidance and recent observations, the forecast consensus also favors a transition to ENSO-neutral during the next few months. In summary, a transition from El Niño to ENSO-neutral is expected in the next month or two, with ENSO-neutral most likely to continue through Northern Hemisphere fall and winter (click CPC/IRI consensus forecast for the chance of each outcome for each 3-month period).

This discussion is a consolidated effort of the National Oceanic and Atmospheric Administration (NOAA), NOAA's National Weather Service, and their funded institutions. Oceanic and atmospheric conditions are updated weekly on the Climate Prediction Center web site (El Niño/La Niña Current Conditions and Expert Discussions). Forecasts are also updated monthly in the Forecast Forum of CPCs Climate Diagnostics Bulletin. Additional perspectives and analysis are also available in an ENSO blog. The next ENSO Diagnostics Discussion is scheduled for 8 August 2019.

To receive an e-mail notification when the monthly ENSO Diagnostic Discussions are released, please send an e-mail message to: ncep.list.enso-update@noaa.gov.

 
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gerontocrat

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Re: 2019 ENSO
« Reply #46 on: August 09, 2019, 05:57:29 PM »
USA CPC says ENSO neutral
Nothing much happening for some time?
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Re: 2019 ENSO
« Reply #47 on: August 24, 2019, 01:23:36 PM »
Time to begin regular updates now the uncertain phase is over with.

What BOM says......

Southern Oscillation Index
The 30-day Southern Oscillation Index (SOI) is close to zero. The SOI for the 30 days ending 18 August was +0.7, with the 90-day value −6.8.

Sustained negative values of the SOI below −7 typically indicate El Niño while sustained positive values above +7 typically indicate La Niña. Values between +7 and −7 generally indicate neutral conditions.

The El Niño–Southern Oscillation (ENSO) remains neutral. The Indian Ocean is expected to be the dominant driver of Australia's climate over the coming months.

The Indian Ocean Dipole (IOD) index has been above the positive IOD threshold for four of the past five weeks, with values strengthening in the past month. However, the broader Indian Ocean patterns of sea surface temperature, cloud, and wind have been positive IOD-like since late May.

All climate models surveyed by the Bureau forecast positive IOD conditions to continue for the southern hemisphere spring. Typically, a positive IOD brings below average winter–spring rainfall to southern and central Australia, above average daytime temperatures for the southern two-thirds of Australia, and increased fire risk in the southeast.

The El Niño–Southern Oscillation (ENSO) remains neutral—neither El Niño nor La Niña. Atmospheric and oceanic indicators of ENSO are mostly close to average, reflecting neutral tropical Pacific cloud patterns and rainfall.

Most climate models indicate the tropical Pacific is likely to remain ENSO-neutral for the rest of 2019, meaning other climate drivers are likely to remain as the primary influences on Australian and global weather.

Rodius

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Re: 2019 ENSO
« Reply #48 on: September 04, 2019, 02:35:20 PM »
Southern Oscillation Index
The 30-day Southern Oscillation Index (SOI) is neutral, with the value for the 30 days ending 1 September at −3.8. The 90-day value was −6.1.

Sustained negative values of the SOI below −7 typically indicate El Niño while sustained positive values above +7 typically indicate La Niña. Values between +7 and −7 generally indicate neutral conditions.

Positive Indian Ocean Dipole persists as ENSO remains neutral
The El Niño–Southern Oscillation (ENSO) remains neutral. The positive Indian Ocean Dipole (IOD) continues to be the main influence on Australian climate.

The IOD index has generally been above the positive IOD threshold since mid-July. The broader Indian Ocean patterns of sea surface temperature, cloud, and wind have been positive IOD-like since late May, contributing to dry conditions affecting most of Australia.

All climate models surveyed by the Bureau indicate the positive IOD is likely to continue for the southern hemisphere spring. Typically, a positive IOD brings below average winter–spring rainfall to southern and central Australia, above average daytime temperatures for the southern two-thirds of Australia, and an increased fire risk in the southeast.

The tropical Pacific Ocean remains neutral with respect to the El Niño–Southern Oscillation (ENSO). Atmospheric and oceanic indicators of ENSO are generally close to average, reflecting neutral tropical Pacific cloud and rainfall patterns.

Most climate models indicate the tropical Pacific is likely to remain ENSO-neutral for the rest of 2019 and into early 2020, meaning other climate drivers, like the IOD, are likely to remain as the primary influences on Australian and global weather.

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Re: 2019 ENSO
« Reply #49 on: September 19, 2019, 06:00:27 PM »
AI Application Able to Predict El Niño Events Up to 18 Months in Advance
https://phys.org/news/2019-09-deep-application-el-nio-events.html


Physical interpretation of the CNN model ENSO forecasts.

A trio of researchers from Chonnam National University, Nanjing University of Information Science and Technology and the Chinese Academy of Sciences has found that a deep learning convolutional neural network was able to accurately predict El Niño events up to 18 months in advance. In their paper published in the journal Nature, Yoo-Geun Ham, Jeong-Hwan Kim and Jing-Jia Luo, describe their deep learning application, how it was trained and how well it worked in predicting El Niño events.

The researchers report that they trained their system using data collected from weather stations over the years 1871 to 1973. Data from such sources included a variety of weather and environmental measurements such as sea temperatures and average ocean heat content. The researchers also trained it on 300 El Niño events that occurred between the years 1961 to 2005. Once the system had been taught to recognize the conditions that lead up to El Niño events, they tested it using data from 1984 to 2017. They report that their system was more accurate than current weather models, correctly identifying 24 out of 34 events, compared to only 20 of the same events identified by conventional modeling. The system was also able to do so 18 months in advance. The researchers also report that their system was able to recognize other events that are believed to lead to El Niño events, such as an Indian Ocean dipole.


ENSO correlation skill in the CNN model.

Yoo-Geun Ham et al. Deep learning for multi-year ENSO forecasts, Nature (2019)
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