Pattern ENSO for 21-22

[MichaelJ]

Yuko Okumuro (Univ Texas) is predicting a new La Nina to start forming in late summer and going through the 21-22 Winter. So if you enjoyed this winter, it is likely we will have a carbon copy (not exact of course) next winter. Pedro DiNezio of Univ of Colorado disagrees with this and says it is very rare for a La Nina to follow itself EXCEPT after a strong El Nino which we did not have in 2019-20. What I gather from this is that if La Nina is to persist into next winter, we will see strong signs of that starting up in the summer on the models

 

[Webberweather53]

La Ninas usually come in multiples of two even if they don't follow strong El Ninos. This one is coming on the heels of multiple years of weak-near borderline El Nino conditions.

 

[Myfrotho704_]

2nd year la ninas are often wall to wall torches

 

[LickWx]

2nd year la ninas are often wall to wall torches

It’s looking likely we will finally get my 1931-1932 winter repeat but even warmer .

 

[Webberweather53]

It’s looking likely we will finally get my 1931-1932 winter repeat but even warmer .

1931-32 delivered in March, at least if you were in RDU & FAY

 

[MichaelJ]

Here is a good site which does a good job of explaining what we are likely to have with solid reasoning why

Climate Prediction Center: ENSO Diagnostic Discussion

www.cpc.ncep.noaa.gov

 

[Webberweather53]

I wrote a relevant pieces on why El Ninos and La Ninas are often different durations in my MS thesis at UNCC.

I'll share some of it here as I think many, even if you're not a meteorologist, would find it interesting and insightful.

"Longer-lived La Ninas would be expected given that during multi-year La Ninas, weaker subsurface winds for a similar changes in SST anomalies, dampens and slows the recharge of the thermocline, ultimately limiting the ability of subsurface anomalies to influence ocean temperatures in the mixed layer (DiNezio and Deser, 2014). Moreover, subsurface cold anomalies from off the equator often get entrained into the equatorial Pacific, interrupting the ENSO’s recharge phase following an El Nino (Hu et al, 2014; Deepak et al, 2019) and disturbing the natural succession of ENSO (Kessler 2002), allowing La Ninas to persist longer. Multi-year La Ninas have also been found to be more likely when they were immediately preceded by an intense El Nino (Wu et al, 2019). Our results agree with these mechanisms. It is also possible that remote forcing of West Pacific trade wind variability from the Indian Ocean may play a role in shaping the behavior of multi-year La Ninas (Ohba and Ueda, 2007; Okumura and Deser, 2010; Dong and McPhaden, 2018). Furthermore, climate models often struggle in forecasting multi-year La Nina events (Hu et al, 2014; Barnston et al, 2010), revealing a potential weakness in our understanding of multi-year La Nina behavior and theories such as the recharge/discharge oscillator (Battisti and Hurst, 1988; Suarez and Schopf, 1988; Jin et al, 1997; Wang, 2001; Hu et al, 2014), although some successful model simulations have been conducted that accurately predict multi-year La Ninas (Dinezio et al, 2017)."

"Moreover, unlike La Ninas, multi-year El Ninos are thought to be more closely linked to timing of their onset in the calendar year as well as their “flavor” (i.e. Central or East-Pacific based) (Wu et al, 2019). Studies such as Wu et al (2019) posit that El Ninos that onset later in the calendar year (late northern summer or fall vs spring) and events that are biased towards the central Pacific (i.e. modoki El Ninos; Ashok et al, 2007) are more likely to persist into the following year because the upwelling Rossby Waves that reflect on the western boundary region and become upwelling Kelvin Waves are delayed late enough in the calendar year such that the east-central Pacific cold tongue and Bjerknes feedbacks become re-established and dampen the impact of the upwelling Kelvin Wave. Also, El Ninos being biased towards the central Pacific make the western Pacific less susceptible to enhanced trade winds due to Indian Ocean warming during El Nino (Kug and Kang, 2006; Ohba and Ueda, 2007; Wu et al, 2019) and central Pacific El Ninos tend to be weaker on average than their traditional counterparts, effectively weakening the subsequent upwelling Kelvin Wave that attempts to weaken the El Nino."

Here's some of the relevant literature cited in these excerpts.

"Nonlinear Controls on the Persistence of La Nina"
https://journals.ametsoc.org/view/journals/clim/27/19/jcli-d-14-00033.1.xml

"What Controls the Duration of El Nino and La Nina Events?"
https://journals.ametsoc.org/view/journals/clim/32/18/jcli-d-18-0681.1.xml

"Impact of multiyear La Niña events on the South and East Asian summer monsoon rainfall in observations and CMIP5 models"
https://link.springer.com/article/10.1007/s00382-018-4561-0

"Why were some La Ninas followed by another La Nina?"
https://link.springer.com/article/10.1007/s00382-013-1917-3

"Is ENSO a cycle of series of events?"
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2002GL015924

"An Impact of SST anomalies in the Indian Ocean in acceleration of the El Nino to La Nina transition"
https://www.jstage.jst.go.jp/article/jmsj/85/3/85_3_335/_article

"Asymmetry in the Duration of El Nino and La Nina"
https://journals.ametsoc.org/view/journals/clim/23/21/2010jcli3592.1.xml

"A Proposed Mechanism for the Asymmetric Duration of El Niño and La Niña"
https://journals.ametsoc.org/view/journals/clim/24/15/2011jcli3999.1.xml

"Unusually warm Indian Ocean sea surface temperatures help to arrest development of El Niño in 2014"
https://www.osti.gov/pages/biblio/1463348

"Verification of the First 11 Years of IRI’s Seasonal Climate Forecasts"
https://journals.ametsoc.org/view/journals/apme/49/3/2009jamc2325.1.xml

"A 2 Year Forecast for a 60–80% Chance of La Niña in 2017–2018"
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017GL074904

"Interactive feedback between ENSO and the Indian Ocean"
https://journals.ametsoc.org/view/journals/clim/19/9/jcli3660.1.xml

 

[Webberweather53]

For those that have liked using my ENS ONI index & associated tables the past several years, I'll soon be making a significant update to this index in the coming days.

Several new datasets will be added to further enhance the quality of the index and the ENS ONI will now extend back to 1850 instead of 1865.

http://www.webberweather.com/ensemble-oceanic-nino-index.html

 

[Webberweather53]

I just finished making a major update to my ENS ONI index, extending it back to 1850, and all my data is presented in excel form so it's easy for everyone to manipulate & download.




Here's what the new, pre-1865 extension looks like.



Also seeing evidence of another El Nino in some instrumental data in/around the winter of 1845-46, documentary and proxy records seem to corroborate this.





Also, highly recommend if you're interested in seeing further extensions of products like ENS ONI further back in time, getting involved w/ citizen science projects like Climate History Australia & OldWeather to help scientists digitize old weather data that can be put back into reanalysis models and datasets to give us a better sense of weather and climate variability over the past few-several centuries. Something like 90% of known ship logbooks from Europe in the early-mid 1800s have yet to be digitized, hundreds of thousands-millions of additional observations are out there just waiting to be put into our reanalysis and statistical reconstruction models...

http://www.webberweather.com/ensemble-oceanic-nino-index.html

Enjoy

 

[Webberweather53]

ENSO really went off the rails it seems like in the early 1800s from the little bit of instrumental data I've looked at and papers I've read through. The stereotypical teleconnections we think about where Australia is dry during El Ninos and vis versa in La Ninas for ex completely broke down in this period. We had several major tropical volcanic eruptions in a row that triggered/sustained multiple, if not several long-lived El Nino events during the 1810s-1840s. The reason for that is believed to be due to the so-called land-ocean temperature gradient/ocean dynamical thermostat mechanism. This process involves reduced shortwave radiation following tropical volcano eruptions causing the Maritime Continent to cool faster than the adjacent West Pacific Ocean. These cooler temperatures lead to surface pressure rises there relative to the West Pacific, slowing the easterly trades down and triggering westerly wind bursts & Kelvin Waves that radiate east into the East Pacific, depress the thermocline, raising the SSTs and ultimately favoring the development of El Nino. This mechanism is also sensitive to initial ENSO state, w/ pre-existing weak, central Pacific El Ninos being most inclined to produce El Ninos following major tropical volcanic eruptions. La Ninas are less receptive because clouds over the maritime continent reduce incoming shortwave radiation and the additional loss of shortwave from volcanic eruptions is less than in El Ninos when skies are clearer.

Here's a pretty decent (& recent) review on this topic: https://www.nature.com/articles/s43247-020-0013-y

 

[Webberweather53]

NINO region SSTs have warmed up in a big week the past week or two as westerly wind bursts from an MJO event propagate thru the Pacific/W Hemisphere. We're also at the time of the year where the SST anomalies, coastal upwelling, & Bjerknes feedback in the east-central Pacific are at their weakest, which means ENSO is most sensitive/susceptible to higher frequency subseasonal "noise" from things like the MJO.




Gonna be closely watching to see if a Kelvin Wave tries to sneak across into the eastern Pacific.

Also btw, if you haven't seen it before, the TAO Buoy site is awesome.

As an important aside: you can actually thank the "Super" El Nino in 1982-83 for having these buoys in the first place. Due to the El Chichon eruption & our reliance on satellite data in the early 80s (these satellite retrievals possessed and unforeseen cold bias via blocking of shortwave by the Sulfur Dioxide aerosols associated w/ the volcanic eruption), this TAO/TRTION buoy network was established to prevent something like that from ever happening again.

https://www.pmel.noaa.gov/tao/drupal/disdel/

 

[Webberweather53]

Piggybacking off the earlier post from above wrt tropical volcano eruptions and the tendency for El Nino to follow them & I know wxhistory buffs like @GaWx will appreciate this, look at how many moderate-strong El Nino events there were in the 1810s-1840s (from written records via Quinn (1987)).
https://spo.nmfs.noaa.gov/sites/default/files/pdf-content/1978/763/quinn.pdf

Six moderate-strong El Nino events in just 14 years?

Now think about how some of these events also likely lasted over a year too... I.e. you basically spent half-2/3rds of an entire decade & a half in moderate or strong El Nino conditions (wtf). We normally go at least 4-7 years or so without seeing just one

 

[LickWx]

Piggybacking off the earlier post from above wrt tropical volcano eruptions and the tendency for El Nino to follow them & I know wxhistory buffs like @GaWx will appreciate this, look at how many moderate-strong El Nino events there were in the 1810s-1840s (from written records via Quinn (1987)).
https://spo.nmfs.noaa.gov/sites/default/files/pdf-content/1978/763/quinn.pdf

Six moderate-strong El Nino events in just 14 years?

Now think about how some of these events also likely lasted over a year too... I.e. you basically spent half-2/3rds of an entire decade & a half in moderate or strong El Nino conditions (wtf). We normally go at least 4-7 years or so without seeing just one



View attachment 78515

Man imagine the global warming from something like that! Also that nino of 1877! Now that’s the biggest of em all!

 

[Webberweather53]

Man imagine the global warming from something like that! Also that nino of 1877! Now that’s the biggest of em all!

Haha ironic you'd say that because the 1810-1840 period was actually & arguably the COLDEST part of the Little Ice Age. It's crazy to think about but El Ninos offset the cooling from volcanic eruptions but are often not enough to cause warming at least initially anyways. When the planet started coming out of this period & warming up in the 1840s-50s, El Ninos became pretty hard to come by, the only significant events I'm aware of for the 20 year stretch from 1840-60 were 1845-46 & 1855-56. May have been a weak El Nino in 1852 but other than that, wasn't much to write home about, but yes the 1877-78 El Nino was a monster and may be the strongest we've seen in the last 200 years. The Great Drought in parts of E Asia, India, & Indonesia caused by the 1877-78 El Nino killed off 3% of the entire world's population due to starvation + crop failures from lack of rainfall. This El Nino event + drought was so bad that some provinces of China didn't see their population recover back to pre 1877-78 El Nino levels until the 1980s. ?

 

[Webberweather53]

 

[MichaelJ]

EXCELLENT work Eric! I have access to the early Moravian written history of the weather in Salem and will try to formulate some kind of pattern and years of cold snowy weather, at least in the Triad. Before anyone gets their panties in a wad, I am not claiming this is absolute proof but those old timers did a god job of recording winters and snowfall

 

[Webberweather53]

La Nina is dying/dead

 

[GaWx]

The latest weekly Nino 3.4 warmed 0.3 C and is back up to -0.7 C. This means the chance at this La Niña ending up peaking as only weak (under -1.0) on an ONI (trimonthly max) basis has increased somewhat. I have been expecting a moderate peak (-1.0 to -1.4 based on 3 months of weeklies averaged out) but this new warming this late in autumn tells me it may not get there. In order to get a -1.0 or colder peak, the weeklies usually have to peak ~-1.2 to -1.3 or colder. The significance of that for SE winters is that mild winters due to SER domination have a good bit higher chance when La Niña is moderate or strong per analogs. But having only a weak La Niña would mean analogs that are closely balanced between AN, NN, and BN in the SE. Actually, after weak to moderate El Niño, your next best shot at a genuinely cold SE winter is weak La Niña. So, I for one am hoping it stays weak.

Edit: I realize we still have to deal with the warm MC. But theres always the dry ice cruise option to cool it down lol.

 

[Mr. Golf]

The latest weekly Nino 3.4 warmed 0.3 C and is back up to -0.7 C. This means the chance at this La Niña ending up peaking as only weak (under -1.0) on an ONI (trimonthly max) basis has increased somewhat. I have been expecting a moderate peak (-1.0 to -1.4 based on 3 months of weeklies averaged out) but this new warming this late in autumn tells me it may not get there. In order to get a -1.0 or colder peak, the weeklies usually have to peak ~-1.2 to -1.3 or colder. The significance of that for SE winters is that mild winters due to SER domination have a good bit higher chance when La Niña is moderate or strong per analogs. But having only a weak La Niña would mean analogs that are closely balanced between AN, NN, and BN in the SE. Actually, after weak to moderate El Niño, your next best shot at a genuinely cold SE winter is weak La Niña. So, I for one am hoping it stays weak.

Edit: I realize we still have to deal with the warm MC. But theres always the dry ice cruise option to cool it down lol.

Larry, I may be wrong about this, but the niña either is now or will soon to be more east based. I usually go to tropicaltidbits sst anomalies and look at all the different regions. It updates every 6 hours and it clearly, if its correct, has 1+2 region cooler than other regions currently. Take a look and let me know

 

[GaWx]

Larry, I may be wrong about this, but the niña either is now or will soon to be more east based. I usually go to tropicaltidbits sst anomalies and look at all the different regions. It updates every 6 hours and it clearly, if its correct, has 1+2 region cooler than other regions currently. Take a look and let me know

Good observation. Actually, as of this latest weekly SST update (based on last week averaged out), Nino 1 + 2 remaining at -1.0 allowed it to become the coolest region albeit only by a small margin. Nino 3 by warming 0.3 to -0.8 moved to 2nd coolest. Nino 3.4 and 4 were both at -0.7 last week making them the warmest. In reality, it is a pretty balanced basin wide weak La Niña right now. But I’ll be looking to see if the gap of 1 + 2 over the others were to later widen.