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AbruptSLR

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Re: 2018 ENSO
« Reply #50 on: February 05, 2018, 05:05:54 PM »
Per the following NOAA weekly Nino index values thru the week centered on Jan 31 2018; the first two images of NOAA's Eq Pac Upper Ocean Heat Anom and SSTA Evolution, respectively; and the last two BoM images of the Nino 3.4 and IOD indices, respectively, thru the week ending Feb 4 2018; the ENSO condition firmly remains in a weak La Nina condition.

                     Nino1+2      Nino3         Nino34        Nino4
 Week           SST SSTA    SST SSTA   SST SSTA    SST SSTA
 27DEC2017     22.1-1.3     24.4-0.9     26.0-0.6     28.2-0.2
 03JAN2018     22.9-0.8     24.0-1.4     25.8-0.8     28.3-0.1
 10JAN2018     23.3-0.9     24.3-1.3     25.6-0.9     28.2-0.1
 17JAN2018     23.9-0.6     24.7-0.9     26.0-0.6     27.9-0.3
 24JAN2018     24.0-0.9     24.7-1.1     25.9-0.7     27.8-0.4
 31JAN2018     24.4-0.9     24.8-1.2     25.8-0.9     27.7-0.5
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: 2018 ENSO
« Reply #51 on: February 05, 2018, 05:08:32 PM »
The four attached images show BoM plots of the weekly Nino index values thru the week ending Feb 4 2018, and show the Nino 1, 2, 3 & 4 indices, respectively.  These plots all indicate that we firmly remain in a weak La Nina condition:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Tor Bejnar

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Re: 2018 ENSO
« Reply #52 on: February 05, 2018, 05:22:03 PM »
Climate Prediction Center - National Centers for Environmental Prediction - National Oceanic and Atmospheric Administration - cpc.ncep.noaa.gov predicts a weak El Nina continuing into the August-September-October period.  Seasonal Nino3.4 E1 shown:

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AbruptSLR

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Re: 2018 ENSO
« Reply #53 on: February 06, 2018, 02:29:47 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved down to +5.9:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Sigmetnow

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Re: 2018 ENSO
« Reply #54 on: February 06, 2018, 07:55:38 PM »
More U.S. drought in a second-year La Niña?
Author: Nat Johnson
February 1, 2018
Quote
Currently, we are fully immersed in the second winter of a “double-dip” La Niña.   Although it will take some time before we can see how this event stacked up with past events, you might have noticed that it has been quite dry over much of the U.S. this winter, with drought expanding across several regions, particularly in the south.  Being the big ENSO fans that you are, you might have asked yourself, are these conditions typical in the second winter of a double-dip La Niña?  And are there any differences in how the atmosphere responds to La Niña in the second winter relative to the first?  Well if either of those questions ever crossed your mind, then you’re in luck!

A recent study (1) led by Dr. Yuko Okumura of the University of Texas at Austin addressed how the impacts of La Niña may change from the first winter to the second for double-dip La Niñas like this one. Spoiler alert: Dr. Okumura and colleagues found evidence that U.S. drought and the North Pacific atmospheric circulation anomalies strengthen in the second winter of a double-dip La Niña.  With that out of the way, let’s take a closer look at what they found.
...
...they found that sea surface temperature anomalies in the Niño3.4 region tend to be about 25-30% weaker in the second La Niña winter relative to the first.  Surprisingly, however, they also found that the atmospheric circulation departures from average over the North Pacific and North America region tend to be stronger in the second winter.
...
The anomalous high pressure over the North Pacific, a characteristic feature of La Niña, is, on average, stronger in the second winter.  These atmospheric circulation anomalies have big implications for the impacts over North America.  Most notably, the occurrence of drought conditions tends to be worse over regions like California and the U.S. Southeast, which also are regions that have been dry so far this winter. ...
https://www.climate.gov/news-features/blogs/enso/more-us-drought-second-year-la-niña
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FishOutofWater

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Re: 2018 ENSO
« Reply #55 on: February 07, 2018, 01:53:22 AM »
Last winter was not a La Niña event by Australian rules. Note the study you cite said the second winter in a 2 year event is weaker. This winter La Niña is stronger, and meets both Bom and NWS criteria for La Niña. California had a very wet winter last year, which is not normal for a La Niña and is having a drought this winter, which is normal.

I think the Australian rules are better than the American rules in this case.

AbruptSLR

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Re: 2018 ENSO
« Reply #56 on: February 07, 2018, 02:39:08 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has remained constant at +5.9:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #57 on: February 08, 2018, 02:35:45 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved down to +5.4:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #58 on: February 09, 2018, 02:28:16 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved down to +4.5:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #59 on: February 10, 2018, 12:59:19 PM »
Per the attached plot issued yesterday by the BoM, the 30-day moving average SOI has drifted down to +4.4:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Sleepy

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Re: 2018 ENSO
« Reply #60 on: February 10, 2018, 01:44:21 PM »
ECMWF Nino plumes for February.
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gerontocrat

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Re: 2018 ENSO
« Reply #61 on: February 10, 2018, 07:25:51 PM »
From the monthly NOAA ENSO Diagnostic Discussion on 8th Feb
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

Quote
Most models in the IRI/CPC plume predict La Niña will decay and return to ENSO-Neutral during the Northern Hemisphere spring 2018 [Fig. 6]. The forecast consensus also favors a transition during the spring with a continuation of ENSO-neutral conditions thereafter. In summary, a transition from La Niña to ENSO-neutral is most likely during the Northern Hemisphere spring (~55% chance of ENSO-neutral during the March-May season) (click CPC/IRI consensus forecast for the chance of each outcome for each 3-month period).
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AbruptSLR

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Re: 2018 ENSO
« Reply #62 on: February 11, 2018, 04:49:48 PM »
Per the attached plot issued yesterday by the BoM, the 30-day moving average SOI has remained constant at +4.4:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #63 on: February 12, 2018, 02:43:26 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved down to +3.4:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

FishOutofWater

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Re: 2018 ENSO
« Reply #64 on: February 12, 2018, 03:32:39 AM »
The ECMWF  forecast is consistent with how the cool tongue and warm pools have been evolving. The CFSv2 has failed badly in the equatorial Atlantic for years and I don't trust it in the Pacific. It doesn't handle equatorial upwelling accurately. In the Atlantic it can't handle the Amazon freshwater plume worth a damn. It fails with the flow of Atlantic heat across the equator. It badly underpredicted the record high heat content in the tropical Atlantic last September.

The CFSv2 also persistently makes the water immediately around Antarctica too warm. It can't handle the ACC and the complex upwelling, downwelling & currents in the southern ocean. I've actually tried to forecast ocean heat content to predict hurricane seasons months ahead of time, but the CFSv2 has been little help.

Tor Bejnar

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Re: 2018 ENSO
« Reply #65 on: February 12, 2018, 03:57:08 PM »
'But it [CFSv2] is so convenient!' I say  ::)
I appreciate your critique, though, Fish.
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AbruptSLR

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Re: 2018 ENSO
« Reply #66 on: February 12, 2018, 05:18:24 PM »
While the attached plots show some limited weakening (i.e. some movement towards neutral conditions) of the current weak La Nina conditions, the following NOAA data thru the week centered on Feb 7 2018, shows that we clearly remain in a weak La Nina state.  The first two NOAA Eq Pac plots show the Upper Ocean Heat Anom and the SSTA Evolution, respectively; while the last two BoM plot show the Nino 3.4 and IOD, indices respectively through the week ending Feb 11 2018:


                     Nino1+2      Nino3         Nino34        Nino4
 Week           SST SSTA    SST SSTA   SST SSTA    SST SSTA
 03JAN2018     22.9-0.8     24.0-1.4     25.8-0.8     28.3-0.1
 10JAN2018     23.3-0.9     24.3-1.3     25.6-0.9     28.2-0.1
 17JAN2018     23.9-0.6     24.7-0.9     26.0-0.6     27.9-0.3
 24JAN2018     24.0-0.9     24.7-1.1     25.9-0.7     27.8-0.4
 31JAN2018     24.4-0.9     24.8-1.2     25.8-0.9     27.7-0.5
 07FEB2018     24.9-0.7     24.9-1.3     25.8-0.9     27.8-0.3

“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #67 on: February 12, 2018, 05:22:27 PM »
The four attached weekly Nino index plots thru the week ending Feb 11 2018, were all issued today by the BoM, and show the Nino 1, 2, 3 & 4 indices, respectively.  Collectively, they show some fluctuation towards neutral conditions, but they also show that we remain in a weak La Nina condition:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Csnavywx

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Re: 2018 ENSO
« Reply #68 on: February 12, 2018, 06:59:39 PM »
The four attached weekly Nino index plots thru the week ending Feb 11 2018, were all issued today by the BoM, and show the Nino 1, 2, 3 & 4 indices, respectively.  Collectively, they show some fluctuation towards neutral conditions, but they also show that we remain in a weak La Nina condition:

A long lived, extreme MJO is contributing to a long-lived, strong westerly wind burst at the moment, which is forecast to persist for a while:





This could be a lethal blow to the current Nina as a decently large EKW propagates across the Pacific:



AbruptSLR

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Re: 2018 ENSO
« Reply #69 on: February 13, 2018, 02:31:03 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved down to +2.5:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #70 on: February 13, 2018, 06:49:21 PM »
The four attached weekly Nino index plots thru the week ending Feb 11 2018, were all issued today by the BoM, and show the Nino 1, 2, 3 & 4 indices, respectively.  Collectively, they show some fluctuation towards neutral conditions, but they also show that we remain in a weak La Nina condition:

A long lived, extreme MJO is contributing to a long-lived, strong westerly wind burst at the moment, which is forecast to persist for a while:

The attached ECMM forecast for MJO shows the prospects for a long-lived WWB declining rapidly in the coming days.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #71 on: February 14, 2018, 02:46:08 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved down to +1.9:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Csnavywx

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Re: 2018 ENSO
« Reply #72 on: February 14, 2018, 06:28:44 AM »
The four attached weekly Nino index plots thru the week ending Feb 11 2018, were all issued today by the BoM, and show the Nino 1, 2, 3 & 4 indices, respectively.  Collectively, they show some fluctuation towards neutral conditions, but they also show that we remain in a weak La Nina condition:

A long lived, extreme MJO is contributing to a long-lived, strong westerly wind burst at the moment, which is forecast to persist for a while:

The attached ECMM forecast for MJO shows the prospects for a long-lived WWB declining rapidly in the coming days.

The EC has been too aggressive with its forecast for the MJO phase to advance (and in amplitude). This is particularly noticeable in phases 4-5-6, where it typically struggles the most.

Regardless, the synoptic pattern in the SHem favors the continuation of westerly anomalies and outright westerly winds (at times) through the EKW generation zone. A stacked rex-block setup all the way to New Zealand is helping to generate a large area of cyclonic turning just south of the equator, which has been favorable for TCs and tropical lows/waves develop and circulate in this region and cause it to persist.

Both the GFS/GEFS and EC/EPS forecast that this condition will persist for at least the next week. This should further strengthen the already significant EKW and thermocline depression that is gathering steam in the WPac.

Lord M Vader

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Re: 2018 ENSO
« Reply #73 on: February 14, 2018, 07:58:39 AM »
Csnavywx: I tend to agree with ASLR here. The GFS model has known troubles around phase 8 and tend to overestimate the MJO in that region. With that said, even if the MJO is declinng it should be enough to initiate a new downvelling Kelvin wave, we shall see.

wolfpack513

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Re: 2018 ENSO
« Reply #74 on: February 14, 2018, 08:24:57 AM »
Discussion from Dr. Klaus Wolter on recent MEI behavior and analogs going further.  Points towards Niño.   [url][https://www.esrl.noaa.gov/psd/enso/mei/#discussion/url]


Alexander555

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Re: 2018 ENSO
« Reply #75 on: February 14, 2018, 10:15:25 AM »
The four attached weekly Nino index plots thru the week ending Feb 11 2018, were all issued today by the BoM, and show the Nino 1, 2, 3 & 4 indices, respectively.  Collectively, they show some fluctuation towards neutral conditions, but they also show that we remain in a weak La Nina condition:

A long lived, extreme MJO is contributing to a long-lived, strong westerly wind burst at the moment, which is forecast to persist for a while:

Just to see if i'm right , and if you would have time to correct me. The MJO is like a moving wheater front that moves from the east of Africa over the north of Australia until somewhere west of the Pasific. And than back to the east of Africa passing the north  of lets say Indonesia. And that in 30 to 60 days.

The attached ECMM forecast for MJO shows the prospects for a long-lived WWB declining rapidly in the coming days.

Csnavywx

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Re: 2018 ENSO
« Reply #76 on: February 14, 2018, 05:23:54 PM »
Csnavywx: I tend to agree with ASLR here. The GFS model has known troubles around phase 8 and tend to overestimate the MJO in that region. With that said, even if the MJO is declinng it should be enough to initiate a new downvelling Kelvin wave, we shall see.

That's fine, but I'm not asserting this solely out of anecdotal experience. I'll provide the justification for my position:

First from Ichikawa and Inatsu 2017:



Also from Kim, et al. 2014:

https://journals.ametsoc.org/doi/full/10.1175/JCLI-D-13-00480.1



The Kim et. al cases were in strong MJO phases, where there's a clear bias towards early weakening in all phases in the EC. The GFS is too amped, as you point out above, but when the event is in 4/5/6, it usually does a superior job of forecasting. This case was no different and would fit perfectly into both papers' datasets. Best to use a blend of the GFS and EC in P7 (or just use the JMA at 10-day leads), and lean heavily towards the GFS when the event is in P4/5/6.
« Last Edit: February 14, 2018, 05:34:17 PM by Csnavywx »

AbruptSLR

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Re: 2018 ENSO
« Reply #77 on: February 14, 2018, 05:36:41 PM »
I don't doubt that we may transition to neutral conditions sometime after March 2018, but I doubt that we will transition before the end of March.  Attached is the ECMM MJO forecast issued today, showing that the recent strong MJO is collapsing rapidly.
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Csnavywx

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Re: 2018 ENSO
« Reply #78 on: February 14, 2018, 06:01:00 PM »
Oh yeah, it'll take at  least 5-6 weeks for that EKW to make it across and have an effect. We'll just have to see how long that WWB lasts. Right now, both the EC and GFS have it through at least D7.

By the way, that's one hell of a SPCZ:


AbruptSLR

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Re: 2018 ENSO
« Reply #79 on: February 15, 2018, 02:41:16 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved down to +1.0:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

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Re: 2018 ENSO
« Reply #80 on: February 17, 2018, 08:33:02 AM »
Big down-welling Kelvin wave continues to strengthen near and west of the dateline.  This will be interesting to watch as is slowly treks east this spring.

AbruptSLR

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Re: 2018 ENSO
« Reply #81 on: February 17, 2018, 08:14:22 PM »
Per the attached plot issued yesterday by the BoM, the 30-day moving average SOI has moved down to +0.0:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #82 on: February 18, 2018, 03:29:02 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has plunged down to -1.5:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #83 on: February 19, 2018, 02:31:55 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved down to -2.4:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #84 on: February 19, 2018, 06:33:03 PM »
The first image of the Eq Pac Upper Ocean Heat Anom was issued today by NOAA and indicates weak La Nina conditions, as do the last two images issued by the BoM which show the weekly Nino 3.4 and the IOD, indices, respectively thru the week ending Feb 18 2018:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #85 on: February 19, 2018, 06:35:23 PM »
The four attached images were all issued today by the BoM with weekly data thru the week ending Feb 18, 2018, and show the Nino 1, 2, 3 & 4 indices, respectively.  This data indicates that we remain in a weak La Nina condition:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #86 on: February 20, 2018, 02:36:28 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has plunged down to -3.8:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #87 on: February 20, 2018, 11:39:55 PM »


The following weekly NOAA Nino data thru the week centered on February 14 2018 (note yesterday was a US holiday), indicates that we remain in a weak La Nina condition:


                     Nino1+2      Nino3         Nino34        Nino4
 Week           SST SSTA    SST SSTA   SST SSTA    SST SSTA
 27DEC2017     22.1-1.3     24.4-0.9     26.0-0.6     28.2-0.2
 03JAN2018     22.9-0.8     24.0-1.4     25.8-0.8     28.3-0.1
 10JAN2018     23.3-0.9     24.3-1.3     25.6-0.9     28.2-0.1
 17JAN2018     23.9-0.6     24.7-0.9     26.0-0.6     27.9-0.3
 24JAN2018     24.0-0.9     24.7-1.1     25.9-0.7     27.8-0.4
 31JAN2018     24.4-0.9     24.8-1.2     25.8-0.9     27.7-0.5
 07FEB2018     24.9-0.7     24.9-1.3     25.8-0.9     27.8-0.3
 14FEB2018     25.5-0.6     25.3-1.1     25.8-1.0     27.7-0.4
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #88 on: February 21, 2018, 02:33:46 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved down to -4.4:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #89 on: February 23, 2018, 12:14:37 AM »
Per the attached plot issued yesterday by the BoM, the 30-day moving average SOI has moved down to -4.8:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #90 on: February 23, 2018, 05:50:45 PM »
Per the attached plot issued yesterday by the BoM, the 30-day moving average SOI has drifted down to -4.9:
« Last Edit: February 24, 2018, 06:32:21 PM by AbruptSLR »
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #91 on: February 24, 2018, 02:30:09 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has remained constant at -4.9:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #92 on: February 25, 2018, 03:40:28 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has remained constant at -4.9:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #93 on: February 26, 2018, 02:32:45 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has drifted up to -4.4:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #94 on: February 26, 2018, 06:45:34 PM »
Per the following NOAA weekly Nino data thru the week centered on Feb 21, 2018; the first two plots issued today by the BoM thru the week ending Feb 25, 2018 for the Nino 3.4 and IOD, indices, respectively, and the last two images issued today by NOAA showing the Upper Ocean Heat Anom and the SSTA Evolution, respectively, for the Eq. Pac.; conditions remain in a weak La Nina condition, but I would guess that there is a 50% chance that ENSO conditions could change to a neutral state by sometime in April:

                     Nino1+2      Nino3         Nino34        Nino4
 Week           SST SSTA    SST SSTA   SST SSTA    SST SSTA
 03JAN2018     22.9-0.8     24.0-1.4     25.8-0.8     28.3-0.1
 10JAN2018     23.3-0.9     24.3-1.3     25.6-0.9     28.2-0.1
 17JAN2018     23.9-0.6     24.7-0.9     26.0-0.6     27.9-0.3
 24JAN2018     24.0-0.9     24.7-1.1     25.9-0.7     27.8-0.4
 31JAN2018     24.4-0.9     24.8-1.2     25.8-0.9     27.7-0.5
 07FEB2018     24.9-0.7     24.9-1.3     25.8-0.9     27.8-0.3
 14FEB2018     25.5-0.6     25.3-1.1     25.8-1.0     27.7-0.4
 21FEB2018     26.2 0.0     25.7-0.9     25.8-1.1     27.9-0.2
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: 2018 ENSO
« Reply #95 on: February 26, 2018, 06:48:34 PM »
The four attached weekly Nino plots were issued today by the BoM thru the week ending Feb 25 2018, and show the Nino 1,2, 3 & 4 indices, respectively.  Together they indicate that the current La Nina condition may likely move toward neutral ENSO conditions as soon as April 2018:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Bruce Steele

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Re: 2018 ENSO
« Reply #96 on: February 26, 2018, 10:24:43 PM »
The JISAO PDO index has come out + .7 for Jan.  I don't know the significance of four years of monthly consecutive PDO numbers but it is the first time in the JISAO  98 year record that it has done so.
 The kelp ecosystem in Southern and Northern Calif. are extremely  stressed. The  Dungeness crab fishery in Oregon is dealing with Domoic acid closures. Alaskan cod fishery is in trouble .

AbruptSLR

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Re: 2018 ENSO
« Reply #97 on: February 27, 2018, 02:39:13 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved down to -5.0:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

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Re: 2018 ENSO
« Reply #98 on: February 27, 2018, 05:21:14 AM »
The JISAO PDO index has come out + .7 for Jan.  I don't know the significance of four years of monthly consecutive PDO numbers but it is the first time in the JISAO  98 year record that it has done so.
 The kelp ecosystem in Southern and Northern Calif. are extremely  stressed. The  Dungeness crab fishery in Oregon is dealing with Domoic acid closures. Alaskan cod fishery is in trouble .

The PDO index is detrended to account for AGW so a prolonged positive event now is much more of a burden on marine life than a similar event 50-100 years ago. 

Sleepy

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Re: 2018 ENSO
« Reply #99 on: February 27, 2018, 09:58:16 AM »
ENSO Frequency Asymmetry and the Pacific Decadal Oscillation in Observations and 19 CMIP5 Models.
https://link.springer.com/article/10.1007/s00376-017-7133-z
https://doi.org/10.1007/s00376-017-7133-z
Quote
Abstract.
Using observational data and the pre-industrial simulations of 19 models from the Coupled Model Intercomparison Project Phase 5 (CMIP5), the El Ni˜ no (EN) and La Ni˜ na (LN) events in positive and negative Pacific Decadal Oscillation (PDO) phases are examined. In the observational data, with EN (LN) events the positive (negative) SST anomaly in the equatorial eastern Pacific is much stronger in positive (negative) PDO phases than in negative (positive) phases. Meanwhile, the models cannot reasonably reproduce this difference. Besides, the modulation of ENSO frequency asymmetry by the PDO is explored. Results show that, in the observational data, EN is 300% more (58% less) frequent than LN in positive (negative) PDO phases, which is significant at the 99% confidence level using the Monte Carlo test. Most of the CMIP5 models exhibit results that are consistent with the observational data.

Quote
Conclusions and discussion
This study examines the modulation of ENSO frequency asymmetry by the different phases of the PDO. Results from observational data show that more EN (LN) events tend to occur in positive (negative) PDO phases. Specifically, EN is 300% more (58% less) frequent than LN in positive (negative) PDO phases. Monte Carlo testing is used to check the significance of the above observational evidence, and the results show that the conclusion, i.e., that EN is more (less) frequent than LN in positive (negative) PDO phases, is statistically significant at the 99% confidence level. Besides the observational evidence, the pre-industrial simulations of 19 CMIP5 models are analyzed using the same method as with the observed data. We find that most of the CMIP5 models exhibitthesameresultsasobservedinbothpositiveandnegative PDO phases, indicating that ENSO frequency asymmetryis indeed modulated by the PDO phases. The modulation of ENSO frequency asymmetry by the PDO may be due to the background SST and circulation patterns in different PDO phases. In positive PDO phases there are notable anomalous westerlies over the central equatorial Pacific, which are associated with the warming SST east of the anomalous low-level wind. Thus, this decadal-scale westerly wind anomaly associated with positive PDO phases may encourage more EN events, rather than LN events, to occur. However, in previous studies (e.g., Newman et al., 2003) it has been argued that the PDO is an ENSO-forced signal. Of course, two possibilities exist—that the PDO influences ENSO or vice versa. In this paper, using observational data and CMIP5 coupled model results, we only seek to reveal the phenomenon that there tend to be more EN events in positive PDO phases, and in doing so we find that this relationship between the PDO and ENSO is statistically significant based on the Monte Carlo test. Besides analysis of observational data and CMIP5 multimodel preindustrial control simulations, sensitivity experiments using numerical models are necessary to fully explore the modulation of ENSO frequency asymmetry by the different PDO phases. Such work has recently begun using a coupled climate model with assimilated SST in the ocean component (Dong et al., 2016). Indeed, it has already been found that this method can reproduce the decadal variation of the East Asian summer monsoon reasonably well (Lin et al., 2016). Thus, further study using model experiments to investigate the associated mechanisms is warranted.
Adding Fig1.
Omnia mirari, etiam tritissima.
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Science is a jealous mistress and takes little account of a man's feelings.