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El Nino 2023-2024


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1 hour ago, GaWx said:

 I agree that phases 4-7 have tended to be underestimated for the last few years due largely to the tropical warm WPac per met. Brad Harvey. As I’ve said, he looks at the WPac area N of Australia. That area actually remains cooler than it has been since 2015 and significantly cooler than 2021-3.

 But what’s happened over the last 7 days? Have the forecasted phases 4-7 strengthened?

A. 1) GEFS (bc) run from 11/30:

IMG_8526.png.a85cfe2b015a7be2c3a16a9cf09dc63c.png
 

2) GEFS (bc) run from today:

IMG_8575.png.69745ab61e13af05d3a816a6159f4332.png

 So, today’s GEFS is actually slightly weaker in 4 and significantly weaker in 5-7.

———————————————

B. 1) EPS (bc) run from 11/30:

IMG_8527.png.f1cef173c59647c43f8faa85bf43c1dc.png
 

2) EPS (bc) run from today:

IMG_8576.png.1e198b5b4877415752ec14d2517c5afc.png

 So, today’s EPS unlike GEFS is a bit stronger in 4/5 and the first part of 6 vs the 11/30 run. However, it then curls back into the COD beyond where the 11/30 run ended.

 So, it is a wash over the last week between the changes of the two models. But note that neither of today’s models has it strong at the end with GEFS just outside the COD in 8 and EPS weak inside the COD of 7. Hopefully, the models won’t trend stronger then and that the actual trek into 8/1/2/3 will end up weak. That’s because weak MJO would mean a much better shot at cold late month into Jan vs mod to strong MJO per this diagram of DJF MJO for E US cold shots:

 

You have to use the VP anomaly charts  for a bigger picture of the forcing going on as it can be underestimated by the RMMs charts. Brad Harvey is using too small a SST zone for it to be relevant to the totality of the WPAC warm pool. One SST region near the MJO 4-7 forcing regions just experienced the highest November SSTs on record.

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2 hours ago, GaWx said:

 Keep in mind that this Dec 7th warming has been well modeled for awhile and I assume you realize this is not anything close to a major SSW, which I figure you know requires the mean 60N winds at 10mb to reverse/drop to <0. As one can see on the EPS run below, the 10 mb wind is still way up at ~+30 m/s as of 12/7. So, the current warming is at best considered a “minor” warming. Per this EPS, the first chance for an actual major SSW isn't for another 3 weeks with the best chance not til January. That’s when the real deal may come:

image.png.91c08263ba1e2905e7a15664eefd3d49.png

 

 

 

Yeah ..I'm aware

I was also looking at the GFS' pressure coordinate temperature progs as a basic metric this morning and it's not clear in that product if there is in fact that type of stratospheric intrusion taking place that leads to the down welling .   But ... in deference to other's data sourcing and so forth I didn't mention it. 

The full manifold of data sources from the American side looks rather climo to me so far.  We'll see.  If one bothers to look at the domain going back to 1979 monitoring, ... warm perturbations occur far more frequently than an actual warm burst that goes on to down well and actually forces the AO domain.

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19 minutes ago, bluewave said:

You have to use the VP anomaly charts  for a bigger picture of the forcing going on as it can be underestimated by the RMMs charts. Brad Harvey is using too small a SST zone for it to be relevant to the totality of the WPAC warm pool. One SST region near the MJO 4-7 forcing regions just experienced the highest November SSTs on record.

1. I’m not sure what Brad’s thinking is, but I’m suspecting he prefers to keep his area limited to the tropics in deference to the ENSO regions being limited to equatorial. Actually, he goes much wider than the 5N to 5S of ENSO and uses 15N to 15S for his N of Australia area. I recall your area going much further north (to ~30N). Are you sure you should be going so far N of the tropics? Isn’t the tropical area the most important? For that matter, isn’t the equatorial the most important?

2. I realize the record Nov SST warmth that you refer to. But the globe, overall, has been at its warmest much of this year by a significant margin with many other areas at record highs during much of the year. So, on a relative basis (a la the Roni way of thinking), is it really that big a deal that the area you referred to has record warmth? Why wouldn’t other record warm regions balance this out?

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7 minutes ago, GaWx said:

1. I’m not sure what Brad’s thinking is, but I’m suspecting he prefers to keep it limited to tropical forcing in deference to the tropical forcing of the ENSO regions. Actually, he goes much wider than the 5N to 5S of ENSO and uses 15N to 15S for his N of Australia area. I recall your area going much further north (to ~30N). Are you sure you should be going so far N of the tropics? Isn’t the tropical area the most important?

2. I realize the record Nov SST warmth that you refer to. But the globe, overall, has been at its warmest much of this year by a significant margin with many other areas at record highs during much of the year. So, on a relative basis (a la the Roni way of thinking), is it really that big a deal that the area you referred to has record warmth? Why wouldn’t other record warm regions balance this out?

It is a big deal if the record SSTs are anywhere in the MJO 4-7 regions with the actual SSTs  near +30C. 
 

C62AB9B8-B5E3-4774-A958-AA18FBCDFD4A.gif.57e0b0b19b549217446864dfb129b64d.gif

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7 minutes ago, bluewave said:

It is a big deal if the record SSTs are anywhere in the MJO 4-7 regions with the actual SSTs  near +30C. 

Does +30C still have the same convective significance that it had when the globe was cooler? Let’s say way on down the road that due to AGW that the entire area of, say, 30N to 30S goes +30C+. Would 30C still have as much significance? Wouldn’t the key convection producing SST be higher then? Again, I’m thinking RONI style.

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12 minutes ago, GaWx said:

Does +30C still have the same convective significance that it had when the globe was cooler? Let’s say way on down the road that due to AGW that the entire area of, say, 30N to 30S goes +30C+. Would 30C still have as much significance? Wouldn’t the key convection producing SST be higher then? Again, I’m thinking RONI style.

It really does since the convection doesn’t care about concepts like RONI . 

4EF261CA-EFCC-485F-AB13-AEBAB093E948.png.d891a50cf59e1c861c7df4fa0c710713.png

843A7399-6E5E-49CB-9BCF-FA196AC9FD00.png.ab3eead6025fa965f951d66aa3143bab.png


 

 

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2 minutes ago, bluewave said:

It really does since the convection doesn’t care about concepts like RONI . 

4EF261CA-EFCC-485F-AB13-AEBAB093E948.png.d891a50cf59e1c861c7df4fa0c710713.png

843A7399-6E5E-49CB-9BCF-FA196AC9FD00.png.ab3eead6025fa965f951d66aa3143bab.png


 

 

 Why is +30C a sort of magical SST? From a wx physics standpoint, why is that SST so important? Why not a different SST?

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30 minutes ago, GaWx said:

 Why is +30C a sort of magical SST? From a wx physics standpoint, why is that SST so important? Why not a different SST?



https://www.nature.com/articles/s41586-019-1764-4

Twofold expansion of the Indo-Pacific warm pool warps the MJO life cycle

Nature volume 575pages 647–651 (2019)Cite this article

Abstract

The Madden–Julian Oscillation (MJO) is the most dominant mode of subseasonal variability in the tropics, characterized by an eastward-moving band of rain clouds. The MJO modulates the El Niño Southern Oscillation1, tropical cyclones2,3 and the monsoons4,5,6,7,8,9,10, and contributes to severe weather events over Asia, Australia, Africa, Europe and the Americas. MJO events travel a distance of 12,000–20,000 km across the tropical oceans, covering a region that has been warming during the twentieth and early twenty-first centuries in response to increased anthropogenic emissions of greenhouse gases11, and is projected to warm further. However, the impact of this warming on the MJO life cycle is largely unknown. Here we show that rapid warming over the tropical oceans during 1981–2018 has warped the MJO life cycle, with its residence time decreasing over the Indian Ocean by 3–4 days, and increasing over the Indo-Pacific Maritime Continent by 5–6 days. We find that these changes in the MJO life cycle are associated with a twofold expansion of the Indo-Pacific warm pool, the largest expanse of the warmest ocean temperatures on Earth. The warm pool has been expanding on average by 2.3 × 105 km2 (the size of Washington State) per year during 1900–2018 and at an accelerated average rate of 4 × 105 km2(the size of California) per year during 1981–2018. The changes in the Indo-Pacific warm pool and the MJO are related to increased rainfall over southeast Asia, northern Australia, Southwest Africa and the Amazon, and drying over the west coast of the United States and Ecuador.

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54 minutes ago, bluewave said:

It really does since the convection doesn’t care about concepts like RONI . 

4EF261CA-EFCC-485F-AB13-AEBAB093E948.png.d891a50cf59e1c861c7df4fa0c710713.png

843A7399-6E5E-49CB-9BCF-FA196AC9FD00.png.ab3eead6025fa965f951d66aa3143bab.png


 

 

Not true.

https://www.researchgate.net/publication/349616356_Defining_El_Nino_indices_in_a_warming_climate

"In a warming climate. changes in tropical rainfall and even the intensity of tropical cyclones are more sensitive to changes in relative SST than to background warming (Johnson and Xie 2010, Ramsay and Sobel 2011). That is, the pattern of mean SST warming is important because the largest increase in rainfall will occur in the regions that warm the most relative to the tropical mean, referred to as the warmer-get-wetter paradigm (Xie at al 2010). Uniform surface warming in the tropics will thus not act to appreciably change the local stability and hence precipitation telconnections associated with ENSO".

I'm sure you will quote your on research and we can continue to have this literary sword fight, or simply wait to see who is right...we should know in about a month.

 

 

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20 minutes ago, 40/70 Benchmark said:

Not true.

https://www.researchgate.net/publication/349616356_Defining_El_Nino_indices_in_a_warming_climate

"In a warming climate. changes in tropical rainfall and even the intensity of tropical cyclones are more sensitive to changes in relative SST than to background warming (Johnson and Xie 2010, Ramsay and Sobel 2011). That is, the pattern of mean SST warming is important because the largest increase in rainfall will occur in the regions that warm the most relative to the tropical mean, referred to as the warmer-get-wetter paradigm (Xie at al 2010). Uniform surface warming in the tropics will thus not act to appreciably change the local stability and hence precipitation telconnections associated with ENSO".

I'm sure you will quote your on research and we can continue to have this literary sword fight, or simply wait to see who is right...we should know in about a month.

 

 

Maybe you didn’t read what you just posted since it actually bolsters my argument. The Western Pacific regions are warming faster so that is where the convection is focusing competing with the El Niño. My reference to RONI was in a different context. The poster I was responding to was implying that the RONI could reduce the forcing there. 

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 Today’s EPS is once again not as weak in late Dec as the prior run. This is the first run without a major SSW member in Dec. But it still has ~45-50 members with a Jan major, similar to yesterday. 
 
 There are ~18% of members that go sub -15, which would be a new record low for the entire late Dec through mid Jan period. Yesterday, there were 19% that were sub -15. There are 10% sub -20 and 2% sub -25.
 
Jan 11th EPS mean:

12/7 run: 14 m/s

12/6 run: 12 m/s

12/5 run: 17 m/s

12/4 run: 14 m/s

12/3 run: 15 m/s

12/2 run: 15 m/s

12/1 run: 18 m/s

11/30 run: 23 m/s

11/29 run: 23 m/s

 So, despite mid to late Dec can-kicking over the last week or so, no can kicking yet for around Jan 11th. I’ll be watching to see if early to mid Jan holds in future runs or if the can kicking spreads into Jan:

 

IMG_8583.png.d4acebad567a3cd2bd5a80062e725dde.png
 

Compare this to the 11/28 run to see how much weaker was Dec on the old run though Jan 5th-12th is weaker on the new run:

IMG_8507.png.a343b3d1a782aaec554381c240979700.png

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20 minutes ago, so_whats_happening said:

Yea sounds about right with how things are looking right now. Im not sure this will have much impact in December maybe the last week we may see a slight warming? Similar progression to the last one but definitely weaker.

u.anom.30.5S-5N.gif

My guess is that the WWB will be fairly significant come go time, with good warming realized

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2 hours ago, bluewave said:

Maybe you didn’t read what you just posted since it actually bolsters my argument. The Western Pacific regions are warming faster so that is where the convection is focusing competing with the El Niño. My reference to RONI was in a different context. The poster I was responding to was implying that the RONI could reduce the forcing there. 

No, I read what I posted quite carefully considering I referenced it in my Outlook. This is why we aren't seeing an atmospheric response commensurate to the ONI....because the ENSO anomalies aren't as prevalent a driver due to the fact that they are partially negated by the sea of warmth. I do agree that the warm pool helped to initially displace the forcing west of where it would have otherwise been when this event was highly east based per SST anomalies. 

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5 hours ago, bluewave said:

It is a big deal if the record SSTs are anywhere in the MJO 4-7 regions with the actual SSTs  near +30C. 
 

C62AB9B8-B5E3-4774-A958-AA18FBCDFD4A.gif.57e0b0b19b549217446864dfb129b64d.gif

How do you explain the following from the link below?

This leads us to the third aspect of the convection–
SST relationship, namely the reduction in convective
activity above SSTs of around 30C.
As documented by
Waliser (1996), these warmest SSTs often occur within
the Pacific warm pool region or the Indian Ocean, with
timescales of weeks to a few months, and are termed
SST ‘‘hot spots’’ or ‘‘warm anomalies.’’ These regions
of warmest SST are often free from convection.

The crucial point that we have attempted to add to the debate is that
current theories on their own do not explain the reduc-
tion in convective activity with SSTs greater than 30C
.

 

https://journals.ametsoc.org/downloadpdf/journals/clim/14/5/1520-0442_2001_014_0633_otrbtc_2.0.co_2.pdf

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1 hour ago, 40/70 Benchmark said:

No, I read what I posted quite carefully considering I referenced it in my Outlook. This is why we aren't seeing an atmospheric response commensurate to the ONI....because the ENSO anomalies aren't as prevalent a driver due to the fact that they are partially negated by the sea of warmth. I do agree that the warm pool helped to initially displace the forcing west of where it would have otherwise been when this event was highly east based per SST anomalies. 

But per the link below, a large portion of 30C area west of the dateline has cooled to almost normal based on 1991-2000 sea surface temps. So how much effect is it going to really have? I dunno, but it doesn't strike me as enough to overwhelm everything. 

The dateline east (ENSO 4) has cooled to just 28.54C per Oisst.

https://psl.noaa.gov/map/clim/sst.anom.anim.week.html

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1 hour ago, mitchnick said:

But per the link below, a large portion of 30C area west of the dateline has cooled to almost normal based on 1991-2000 sea surface temps. So how much effect is it going to really have? I dunno, but it doesn't strike me as enough to overwhelm everything. 

The dateline east (ENSO 4) has cooled to just 28.54C per Oisst.

https://psl.noaa.gov/map/clim/sst.anom.anim.week.html

Yeah, the recent convection must have cooled those waters. I think the maritime content had 30c but those were shallow. In nino 4 east of the dateline though, the warm waters run much deeper and have more energy to feed convection in mjo 7-8-1.

I predicted in my outlook that all mjo phases would be wide open especially as the IOD faded. Well, the IOD faded a bit a month early, so its good that mjo is going through 4-6 outside of prime climo. It was to be expected though, rather than be seen as bad news. We just have to wait the mjo out and the pieces will be set where we want them to be. 

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2 hours ago, mitchnick said:

But per the link below, a large portion of 30C area west of the dateline has cooled to almost normal based on 1991-2000 sea surface temps. So how much effect is it going to really have? I dunno, but it doesn't strike me as enough to overwhelm everything. 

The dateline east (ENSO 4) has cooled to just 28.54C per Oisst.

https://psl.noaa.gov/map/clim/sst.anom.anim.week.html

I don't think it will. I am talking about earlier when el Nino was weaker and more east-based.

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14 hours ago, griteater said:
My guess is that the WWB will be fairly significant come go time, with good warming realized


Yes. I agree with you, I think the WWB ends up stronger than modeled and it warms 3.4 substantially by the end of December, but in the grand scheme of things, if I turn out to be right or Ray @40/70 Benchmark turns out to be right, it won’t make a damn bit of difference….a +1.9C trimonthly or a +2.1C/+2.2C trimonthly isn’t going to change the atmospheric response, it’s still going to be the exact same. We are talking about a difference of 0.3. Like @Bluewave said, Mother Nature isn’t going to say “let me respond completely differently to a +1.9C and a +2.2C”

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10 hours ago, GaWx said:

How do you explain the following from the link below?

This leads us to the third aspect of the convection–
SST relationship, namely the reduction in convective
activity above SSTs of around 30C.
As documented by
Waliser (1996), these warmest SSTs often occur within
the Pacific warm pool region or the Indian Ocean, with
timescales of weeks to a few months, and are termed
SST ‘‘hot spots’’ or ‘‘warm anomalies.’’ These regions
of warmest SST are often free from convection.

The crucial point that we have attempted to add to the debate is that
current theories on their own do not explain the reduc-
tion in convective activity with SSTs greater than 30C
.

 

https://journals.ametsoc.org/downloadpdf/journals/clim/14/5/1520-0442_2001_014_0633_otrbtc_2.0.co_2.pdf

Through the rich get richer mechanism. The WPAC warm pool is one of the regions that sees an increase in tropical convection with warming SSTs. The paper you mentioned discussed subsidence regions in other areas of tropical oceans with warming. The previous papers I posted about the WPAC show increased convection there with rising SSTs and stronger MJO phases. 
 

https://www.pnas.org/doi/full/10.1073/pnas.0601798103#:~:text=The “anomalous gross moist stability,because of enhanced moisture convergence.

The “anomalous gross moist stability” or “rich-get-richer” mechanism (12) hypothesizes that the upped-ante differential moisture increase will yield increased precipitation within the convection zones because of enhanced moisture convergence. This mechanism also contributes to drying outside the strong convection zones and likewise should yield an approximately fixed spatial pattern whose amplitude grows in time with the tropospheric warming.

Among these are drying regions in Central America, the Caribbean, equatorial South America, and along the Atlantic intertropical convergence zone. Precipitation increases tend to occur inside the convection zones, including increases in the Southeast Asian summer monsoon. Increased precipitation also occurs in the equatorial Pacific, associated with changes in the dynamics of the equatorial cold tongue and local sea-surface temperature increase (1518).


46D47021-496D-4B01-AEC6-F23A0F554260.thumb.jpeg.34aceed8e47d6288d40c5a44a922a128.jpeg

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8 hours ago, snowman19 said:


Yes. I agree with you, I think the WWB ends up stronger than modeled and it warms 3.4 substantially by the end of December, but in the grand scheme of things, if I turn out to be right or Ray @40/70 Benchmark turns out to be right, it won’t make a damn bit of difference….a +1.9C trimonthly or a +2.1C/+2.2C trimonthly isn’t going to change the atmospheric response, it’s still going to be the exact same. We are talking about a difference of 0.3. Like @Bluewave said, Mother Nature isn’t going to say “let me respond completely differently to a +1.9C and a +2.2C”

Yea, funny that after all of that bickering we essentially agreed. Just a neurotic display of our passion, which is why we focus and argue over the most subtle of details.

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