2015 El Niño?

[wili]

Thanks for these, Tor, but could you remind us what the difference is between them? I see that the top one says 'corrected' but does that mean the bottom one was faulty? If so, why should we even look at it?

(Apologies if this has been explained a hundred times and I missed it, or if, as is likely, the answer is obvious and right before my eyes, but I can't see it!  )

[Tor Bejnar]

I'm so totally not an expert in this area that you shouldn't believe me but here goes...   
I have picked up the impression that the "corrected" version is influenced by historic experience and dampens projected extreme events such as what we are now experiencing.  The 'uncorrected' version may be over-influenced by the extreme events/environments we are now experiencing.  In recent months, I've seen 'credible' projections of future values be between what the two graphs predict. [It isn't me to say who makes credible projections, though.]

[wili]

Thanks tons, Tor. That's about 100% more than I knew before.

[sedziobs]

To add to what Tor said, I believe the "uncorrected" one is the output of the dynamic model, and the corrected version adds a statistical component.  "PDF corrected" indicates that the probability density function has been altered to account for seasonal climatology.  Neither one is necessarily "correct" in the true sense of the word.  The PDF correction may be seen as tuning the model with hindcasts, though I would say it is unclear how much can be gleaned from hindcasts when dealing with possibly unprecedented events.

[bbr2314]

The first two images were issued today by the BoM with data through the week ending August 23 2015 and show the Nino 3.4 (which has moved up to +1.89)and the IOD indices, respectively.

The third & fourth images were issued today by NOAA showing data for August 21 2015 for the modeled Eq. Pac. Subsurface Temp Anoms, and for the modeled Sea Level Anoms, respectively.

Collectively this data indicates to me that conditions are setting-up well for a fourth EKW pulse (with the current third pulse beginning now to reflect off of South America) for our currently strong El Nino event, which (if it occurs) should strengthen this El Nino into the very strong category, particularly if the IOD move from neutral to be above the +0.5 threshold.

Do you have a link to the sea level anomaly map source at the bottom? Would love to explore more. Interesting to look off the NE US coast as 09-10 Nino had an abrupt SLR event and the current look is not dissimilar?

[AbruptSLR]

The first two images were issued today by the BoM with data through the week ending August 23 2015 and show the Nino 3.4 (which has moved up to +1.89)and the IOD indices, respectively.

The third & fourth images were issued today by NOAA showing data for August 21 2015 for the modeled Eq. Pac. Subsurface Temp Anoms, and for the modeled Sea Level Anoms, respectively.

Collectively this data indicates to me that conditions are setting-up well for a fourth EKW pulse (with the current third pulse beginning now to reflect off of South America) for our currently strong El Nino event, which (if it occurs) should strengthen this El Nino into the very strong category, particularly if the IOD move from neutral to be above the +0.5 threshold.

Do you have a link to the sea level anomaly map source at the bottom? Would love to explore more. Interesting to look off the NE US coast as 09-10 Nino had an abrupt SLR event and the current look is not dissimilar?

bbr2314

The first link to a NASA site periodically reports observed sea level anoms.

The second & third links leads to information from NOAA computer models:

https://sealevel.jpl.nasa.gov/science/elninopdo/latestdata/'
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/weeklyenso_clim_81-10/wksl_anm.gif
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/enso.shtml#current

Best,
ASLR

[AbruptSLR]

Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved up to -21.5:

[bigB]

To add to what Tor said, I believe the "uncorrected" one is the output of the dynamic model, and the corrected version adds a statistical component.  "PDF corrected" indicates that the probability density function has been altered to account for seasonal climatology.  Neither one is necessarily "correct" in the true sense of the word.  The PDF correction may be seen as tuning the model with hindcasts, though I would say it is unclear how much can be gleaned from hindcasts when dealing with possibly unprecedented events.

This agrees with my understanding of the two versions. I personally believe the PDF corrected version has more skill, but I also believe it's currently a bit underdone. Nonetheless, I can't see this event peaking at or above +3.0 deg c as suggested by the uncorrected version (ASLR laughs).



Separately, provided below is a link to a newly released article from NOAA's ENSO blog in which Ken Takahashi discusses two relatively new indices that can be used to classify different types of El Ninos based on SSTA patterns in the Central and Eastern Pacific. He also uses these indices to show how this event is currently measuring up to other extreme El Nino events such as the 1972-73, 1982-83, and 1997-98. Per the data presented in this article, Eastern Pacific warming currently falls in between the 1982-83 and 1997-98 events, and near the 1972-73 event. HOWEVER, Central Pacific warming for this event is notably warmer. The author also points out that this event shares some similarities with the 2009-10 El Nino, and that perhaps, it could become a stronger version of that event (see attached image).

https://www.climate.gov/news-features/blogs/enso/one-forecaster%E2%80%99s-view-extreme-el-ni%C3%B1o-eastern-pacific

[Csnavywx]

I keep seeing the 2009-2010 analog pop but frankly, from this meteorologist's standpoint, it's a horrible comparison. Let me illustrate:

[Csnavywx]

As you can see, the thermocline and warm pool progression has MUCH more in common with 82-83 and 97-98 than 09-10. Let's assume I'm being a bit hasty, though. 09-10 didn't get going until later, so let's "cheat" a bit and compare it to that event's peak:


Nope, still not even close. Thermocline progression STILL doesn't hold a candle, even with this wild adjustment. Neither do the zonal wind anomalies.

[bigB]

Csnavywx,

Did you not read my post correctly (or did I misunderstand your post)? The author said it could possibly become a stronger version of the 2009-10 El Nino. That was NOT my opinion. Also, this is the first time I've seen the 2009-10 comparison pop up in months.

Anyway, if one were to believe a model months in advance (which could prove to be a fool's errand) then this event becomes somewhat similar in appearance to the 1982-83 event, but peaks early like the 1997-98 event. This is also based on the uncorrected version of the CFSv2. Just fun and interesting to look at. Yes, I know that not all El Ninos are created equal, and that this one is evolving slightly different to than other major events.

EDIT: Here's the direct quote from the author (Note: Fig 3 is the graph i attached in my earlier post):

However, the eastern Pacific (E index) has been tracking the substantially weaker 1972 event and it would have to surge upwards, as in 1982, to become extreme (Fig. 3b). A quite different outcome could be that E keeps following 1972, remaining below the extreme threshold, while the central Pacific continues to warm into perhaps a larger version of the 2009-2010 El Niño (see bottom graph of Figure 3

2nd EDIT: Gotta give credit where credit is due. Ken Takahashi has a Ph.D in atmospheric science and has authored more than a dozen peer reviewed papers. He was just stating a "possibility". 

[bigB]

The CFS model is calling for a new WWB near/just west of the Dateline region around early-mid September, associated with constructive interference between a moderate convectively coupled ER wave and the El Nino base state. This would increase the odds of TC genesis. If TCs were to develop and close enough to the equator then it would help reinforce westerly winds/anomalies. I wouldn't rule out a CCKW or a weak active phase of the MJO, but any moderate-strong MJO activity seems highly unlikely. We shall see.

[Csnavywx]

bigB, those posts weren't directed at you personally, so sorry if it came off that way. I know it was his opinion. I just think the mention of even a possibility of a "stronger 09-10" misses the boat completely wrt the recent evolution of this event.

It has far more in common with the two "big ones" thusfar than either 72-73 or 09-10. He sort of admits that indirectly by pointing out the difference in the PDO and zonal winds thusfar, so even a mention of a "stronger 09-10" is a bit puzzling. Hell, even the CFSv2 charts you posted there still keep the strongest anomalies near 120W. That's not a CP Nino like 09-10 was.

Perhaps part of the issue is a) the small sample size of strong Ninos and b) our desire to categorize them into types. Mother nature doesn't particularly like being confined to boxed definitions and tends to act more on a continuum. It's entirely possible we might be looking at a "hybrid" of the two Nino types later in the year, but that's going to depend completely on how it evolves from here.

[AbruptSLR]

I personally believe the PDF corrected version has more skill, but I also believe it's currently a bit underdone. Nonetheless, I can't see this event peaking at or above +3.0 deg c as suggested by the uncorrected version (ASLR laughs).

bigB,

No one has a crystal ball to tell the future, but I agree with Csnavywx that our current event has much more similarities to the 82-83 and 97-98 events than other recent El Nino events.  Also, the NASA forecast for January 2016 projecting that the Nino 3.4 will exceed +3.0 C is a PDF corrected projection, so the real question is whether the NASA forecast has good skill in a warming world.  We will all find out in about five months; however, for now the attached Earth Surface Wind & TPW map for August 30 2015 shows: (a) a moderately strong SPCZ; (b) a strong ITCZ moved well north of the equator; (c) a considerable number of tropical storms being generated in the Eastern Tropical Pacific area and migrating northwest; and (d) a Walker Cell in an El Nino pattern.  To me all of these are signs that our current El Nino will continue to gain strength in early September.

Best,
ASLR

[bigB]

The first attachment shows the NCEP CFSR global SSTA for August 20th, 1982 and Jan 1st, 1983.

The Second attachment shows the NCEP CFSR global SSTA for August 20th, 1997, and November 26th, 1997.

Just a view of what the 1982-83 and 1997-98 El Nino events looked like at this time, and what they looked like around the time they peaked (at least per this dataset). I suspect that this event will ultimately peak somewhere in between the two. Unfortunately, these maps generally run about a month behind so I wasn't able to provide an image of August 20th, 2015 for comparison.

Here's a link to these SSTA maps (and others), which are daily and go all the way back to Janurary 1st, 1979:

http://cci-reanalyzer.org/Reanalysis_daily/

EDIT: The third attachment shows the mid-August IRI ENSO predictions plume.

IRI ENSO forecast: http://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/

ASLR and Csnavywx,

It appears there's some confusion here...

Look at my above post from August 22nd. I clearly state that I believe this event will peak somewhere between the 1982-83 and 1997-98 El Nino events. I have also used/mentioned several ENSO indices/indicators (i.e. the ESPI, SOI, Nino indices, MEI, and equatorial upper ocean heat anoms) to show how this event is in the same league as the 1982-83 and 1997-98 El Ninos. I realize that this event has been evolving differently than other major events, and that not all El Ninos are alike. I suspect that this event will peak with at least one ONI value in the +2.0 to +2.2 deg c range during the late Fall/early Winter time-frame. If we're talking monthly OISST.v2 data, I suspect that this event will peak somewhere in the +2.2 to +2.6 deg c range. The Monthly OISST.v2 value for August 2015 looks to come in at about +2.0 deg C. This is why I think the CFS.v2 PDF corrected version is underdone (but it's better to undershoot than overshoot). Depending on how things look around mid-September, I may change my predictions.

Also, I was referring to the PDF corrected version of the CFS.v2 forecast. The NASA GEOS5 forecast is extremely bullish (up near +4.0 deg c), with the lowest member near +3.0. So it makes sense that using a PDF correction would only going bring it down to slightly above +3.0. Anything is possible I guess.

Lastly, the 1982-83 event had slightly more warming in Central equatorial Pacific than the 1997-98 event, and slightly less warming in the Eastern equatorial Pacific. My guess would be that this event ends up looking more like the 1982-83 event in the equatorial Pacific. Of course this doesn't mean it will have exactly the same global impacts. We're entering somewhat uncharted territory here. I guess we'll see...

[AbruptSLR]

bigB,

All of your points are very well taken.  Nevertheless, per the attached figure and the linked article (& extract) the average of the PDF corrected IRI/CPC dynamic forecasts (from mid-August 2015) show the Nino 3.4 index higher than that for the 97-98 event for every month of the year.  So whether one takes three month ONI average values or monthly OISST.v2 average values, the corrected models forecast that we will likely exceed the 97-98 event (but no guarantees), even without giving undue weight to the NASA GMAO forecast.

http://www.washingtonpost.com/blogs/capital-weather-gang/wp/2015/08/21/forecast-models-are-now-calling-for-this-el-nino-to-be-the-strongest-on-record/

Extract: " El Nino, which is a measure of how abnormally warm the tropical Pacific Ocean is, can be classified as “very strong” if surface waters are running at least 2 degrees Celsius warmer than average for at least three months in a row. While this can be a difficult metric to achieve — it’s only happened twice before — it’s looking more like this year will not only jump that hurdle, but also surpass the old record."

Very best,
ASLR

[bigB]

ASLR,

Lets take a quick look at the SST data. As we can see, this El Nino started off stronger than the 1997-98 El Nino, due to an already existing El Nino base state. However, 2015 has since fallen significantly behind the 1997-98 event in the Nino 1+2 and 3 regions, and just slightly behind in the Nino 3.4 region (depending on the data). The Nino 4 region was also cooler at this time during 1997, which along with the significantly warmer Nino 1+2 and 3 regions, would've acted to enhance the coupled ocean-atmosphere system. The 1997-98 event was a very fast paced beast. SSTs went from near La Nina thresholds to strong El Nino thresholds in a matter of 6-7 months, as can be seen in the data provided below. However, the 1982-83 El Nino evolved at slower pace, but eventually became almost as strong as the 1997-98 El Nino. This event seems to be a slow but steady builder like the 1982-83 event. However, It appears this event will peak early like the 1997-98 event. This data indicates that we are currently ahead of the 1982-83 event but slightly behind the 1997-98 event (especially, in the Nino 1+2 and 3 regions). This is further supported by several other atmospheric and oceanic ENSO indices/indicators. As a surfer from So Cal, I hope you're right.

Link to this data: http://www.cpc.ncep.noaa.gov/data/indices/

Weekly OISST.v2 for May-late August 1997 and 2015

                        Nino1+2        Nino3         Nino34      Nino4
 Week             SST SSTA      SST SSTA   SST SSTA   SST SSTA
 07MAY1997     26.8 2.2     28.2 1.0     28.6 0.8     29.4 0.8
 14MAY1997     26.7 2.4     28.0 0.9     28.5 0.6     29.3 0.6
 21MAY1997     26.6 2.6     27.9 1.0     28.6 0.8     29.5 0.7
 28MAY1997     26.8 3.1     28.1 1.3     28.8 1.0     29.5 0.7
 04JUN1997     26.4 3.1     28.0 1.3     28.8 1.1     29.4 0.6
 11JUN1997     26.5 3.5     28.1 1.6     28.9 1.2     29.3 0.5
 18JUN1997     26.0 3.3     28.2 1.8     29.0 1.4     29.4 0.6
 25JUN1997     26.2 3.7     28.2 2.0     29.1 1.6     29.5 0.7
 02JUL1997     25.9 3.7     28.1 2.1     29.0 1.5     29.4 0.6
 09JUL1997     25.7 3.8     28.0 2.2     28.9 1.6     29.5 0.7
 16JUL1997     25.7 4.1     28.1 2.5    29.0 1.8     29.5 0.7
 23JUL1997     25.5 4.1     27.9 2.4    28.8 1.7     29.5 0.8
 30JUL1997     25.2 4.0     27.9 2.6    28.9 1.9     29.5 0.8
 06AUG1997    25.3 4.3     27.8 2.6    28.8 1.8     29.4 0.7
 13AUG1997    25.4 4.6     27.9 2.9    28.9 2.0     29.3 0.6
 20AUG1997     24.2 3.6     27.9 2.9    28.9 2.1     29.2 0.5

                        Nino1+2        Nino3         Nino34      Nino4
 Week             SST SSTA      SST SSTA   SST SSTA   SST SSTA
06MAY2015     26.9 2.3     28.4 1.2     28.8 1.0     29.9 1.2
 13MAY2015     26.4 2.1     28.2 1.1     28.8 1.0     29.8 1.1
 20MAY2015     26.6 2.6     28.2 1.2     28.9 1.1     29.8 1.1
 27MAY2015     26.3 2.6     28.2 1.4     29.0 1.3     29.9 1.1
 03JUN2015     25.3 1.9     28.1 1.4     29.0 1.2     30.0 1.2
 10JUN2015     25.7 2.6     28.1 1.5     29.0 1.3     29.9 1.1
 17JUN2015     25.4 2.7     28.2 1.8     29.0 1.4     29.9 1.1
 24JUN2015     25.1 2.6     28.1 1.9     28.9 1.4     29.9 1.1
 01JUL2015     24.9 2.7     28.0 2.0     28.9 1.4     29.8 1.0
 08JUL2015     25.2 3.3     27.9 2.1     28.8 1.5     29.9 1.1
 15JUL2015     24.6 2.9     27.9 2.3     28.9 1.7     29.8 1.0
 22JUL2015     23.7 2.3     27.6 2.1     28.8 1.6     29.8 1.0
 29JUL2015     23.9 2.7     27.4 2.1     28.8 1.7     29.7 1.0
 05AUG2015     23.6 2.6     27.6 2.3     28.9 1.9     29.6 0.9
 12AUG2015     22.8 2.0     27.3 2.2     28.9 2.0     29.6 0.9
 19AUG2015     22.4 1.7     27.2 2.2     28.9 2.1     29.7 1.1



Monthly OISST.v2 values for Jan-Jul 1982, 1997, and 2015

YR    MON  NINO1+2   ANOM   NINO3    ANOM   NINO4    ANOM  NINO3.4    ANOM         
1982   1   24.29         -0.17    25.87      0.24      28.30    0.00     26.72         0.15
1982   2   25.49         -0.58    26.38      0.01      28.21    0.11     26.70        -0.02
1982   3   25.21         -1.31    26.98     -0.16      28.41    0.22     27.20        -0.02
1982   4   24.50         -0.97    27.68      0.18      28.92    0.42     28.02         0.24
1982   5   23.97         -0.23    27.79      0.71      29.49    0.70     28.54         0.69
1982   6   22.89          0.07    27.46      1.03      29.76    0.92     28.75         1.10
1982   7   22.47          0.87    26.44       0.82     29.38    0.58     28.10         0.88

YR    MON  NINO1+2   ANOM   NINO3    ANOM   NINO4    ANOM  NINO3.4    ANOM
1997   1   23.67         -0.79    24.70    -0.93      28.41     0.11    25.96        -0.61
1997   2   25.74         -0.33    25.75    -0.62      28.33     0.23    26.36        -0.36
1997   3   26.95          0.43    26.98    -0.16      28.52     0.33    27.03        -0.19
1997   4   26.64          1.17    27.59     0.09      29.32     0.82    28.03         0.25
1997   5   26.71          2.51    28.06     0.98      29.45     0.66    28.60         0.75
1997   6   26.27          3.45   28.14    1.71      29.40     0.56    28.94         1.29
1997   7   25.59          3.99    28.01    2.39    29.50     0.70    28.92         1.70

YR    MON  NINO1+2   ANOM   NINO3    ANOM   NINO4    ANOM  NINO3.4    ANOM
2015   1   24.13       -0.39       25.99     0.36      29.16      0.86   27.10        0.53
2015   2   25.59       -0.55       26.55     0.18      29.12     1.02    27.29        0.56
2015   3   26.69        0.06       27.29     0.15      29.32     1.13    27.79        0.58
2015   4   26.95        1.35       28.17     0.67      29.73     1.23    28.56        0.78
2015   5   26.71        2.43       28.28     1.19      29.88     1.09    28.88        1.03
2015   6   25.42        2.54       28.10     1.66      29.93     1.09    28.96        1.32
2015   7   24.48        2.87       27.79     2.17      29.80     1.00    28.82        1.60



Monthly ERSST.v4 values for Jan-Jul 1982, 1997, and 2015
 
 YR   MON  NINO1+2  ANOM   NINO3   ANOM   NINO4    ANOM   NINO3.4  ANOM
1982   1     24.62    -0.10     26.00      0.20    28.29      -0.06     26.84      0.13
1982   2     25.63    -0.55     26.51    -0.03     28.14      -0.07     26.69     -0.19
1982   3     25.66    -0.91     27.24    -0.05     28.44       0.12     27.52      0.16
1982   4     25.09    -0.59    27.72      0.11     28.95       0.36     28.13      0.28
1982   5     24.33    -0.15    27.74      0.45     29.30       0.41     28.46      0.50
1982   6     23.42     0.27    27.23      0.61     29.37       0.47     28.33      0.60
1982   7     22.47     0.42    26.29      0.47     29.01       0.17     27.76      0.45

YR   MON  NINO1+2  ANOM   NINO3   ANOM   NINO4    ANOM   NINO3.4  ANOM
1997   1      23.94   -0.77     24.97    -0.83    28.41     0.06      26.16     -0.55
1997   2      26.16   -0.01     25.83    -0.71    28.45     0.25      26.49     -0.39
1997   3      27.07    0.51     26.91    -0.38    28.64     0.32      27.03     -0.33
1997   4      26.50    0.83     27.53    -0.09    29.31     0.73      28.01      0.17
1997   5      26.40    1.93     27.90    0.61     29.51     0.62      28.52      0.56
1997   6      25.92    2.77     28.02    1.39    29.35     0.46      28.82      1.09
1997   7      25.36    3.32     27.74    1.93     29.46     0.61      28.75      1.44

YR   MON  NINO1+2  ANOM   NINO3   ANOM   NINO4    ANOM   NINO3.4  ANOM
2015   1     24.64     -0.08     26.22    0.43      29.10    0.75     27.21        0.50
2015   2     25.84     -0.34     26.66    0.12     28.99     0.79      27.24       0.36
2015   3     26.71      0.15     27.51    0.22      29.15    0.83      27.78       0.42
2015   4     26.31      0.63     28.23    0.62      29.61    1.02      28.58       0.74
2015   5     25.66      1.19     28.19    0.90      29.83     0.95     28.83       0.87
2015   6     25.10      1.95     27.87    1.24      29.77     0.87     28.70       0.97
2015   7     24.31      2.27     27.43    1.61      29.67     0.83     28.51       1.21


ONI values DJF-MJJ 1982, 1997, and 2015

SEAS  YR   TOTAL   ANOM
DJF  1982  26.70  -0.02
JFM  1982  27.02   0.09
FMA 1982  27.45   0.19
MAM 1982  28.04   0.45
AMJ  1982  28.31   0.61
MJJ  1982   28.18    0.67

SEAS  YR   TOTAL   ANOM
DJF  1997  26.27  -0.50
JFM  1997  26.57  -0.42
FMA 1997  27.19  -0.18
MAM 1997  27.87   0.14
AMJ  1997  28.46    0.61
MJJ  1997  28.70    1.03

SEAS  YR   TOTAL   ANOM
DJF  2015   27.29   0.52
JFM  2015   27.42   0.43
FMA 2015   27.88   0.51
MAM 2015  28.41   0.68
AMJ  2015  28.71    0.86
MJJ  2015   28.69   1.02

[AbruptSLR]

Per the attached plot issued today by the BoM, the 30-day moving average SOI has drifted down to -21.6:

[bigB]

ASLR,

Thought you might like this plot (based on weekly OISST.v2 data) from Jan Null showing 2015 keeping pace with the 1997-98 event in the Nino 3.4 region.

https://twitter.com/ggweather/status/636637819558039552?ref_src=twsrc

[AbruptSLR]

ASLR,

Thought you might like this plot (based on weekly OISST.v2 data) from Jan Null showing 2015 keeping pace with the 1997-98 event in the Nino 3.4 region.

bigB,

Thanks for all of the great data; and we will all find-out together in a few months how the 2015-16 event unfolds; nevertheless, I would like to point-out that your arguments are mostly statistical in nature and down-play much of the physics considered by the dynamic forecasts that I cited.  For example, with it is true that currently the Nino 1+2 index is running behind the 97-98 event; nevertheless, the current EKW pulse is just now surfacing off the coast of Ecuador and I expect the current Nino 1+2 index to increase rapidly over the coming weeks.  Also, as both the ocean and the atmosphere current are in sync. I expect continued Bjerknes feedback to strengthen our current El Nino event.

Keep the excellent data coming, as I am sure that we all will learn a lot by watching the could event unfold, while comparing it to both model and observational data.

Best,
ASLR

[AbruptSLR]

Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved up to -21.1:

[AbruptSLR]

The attached image issued today indicates that Bjerknes feedback is inducing sustained westerlies with a moderate WWB occurring around August 31:

[AbruptSLR]

Per the attached plot issued today by the BoM, the 30-day moving average SOI is still below -20 and is now -20.6:

[bigB]

Just for fun...... 

The attached image shows a close up of tropical Pacific SSTA maps for August 20th, 1982 (top), 2015 (center), and 1997 (bottom). I placed 2015 in between 1982 and 1997, as that's where this event "currently" falls. However, this event is clearly very close to the 1997 event in the Nino 3 and 3.4 regions.

PLEASE NOTE: The SSTA map for 2015 was generated from high resolution daily OISST.v2 data, while the maps for 1982 and 1997 were generated from CFSR data. The climatological base period used for the 2015 map is slightly different than the climatological base period used for 1982 and 1997 maps, but not enough to make a difference. Also, I was able to lower the resolution of the 2015 map by reducing the image noise. That brought the 2015 map more inline with the lower resolution 1982 and 1997 maps. Regardless, this is not a totally accurate comparison, but it's close enough to get a rough idea. Lastly, I marked the equator and dateline.

[AbruptSLR]

Per the following data and the attached plot issued today by the BoM, the 30-day moving average SOI has been below -20 for fourteen continuous days and is now at -20.1:

20150717,20150815,-20.2
20150718,20150816,-20.3
20150719,20150817,-20.5
20150720,20150818,-21.3
20150721,20150819,-22.7
20150722,20150820,-22.2
20150723,20150821,-22.3
20150724,20150822,-21.9
20150725,20150823,-22.0
20150726,20150824,-21.5
20150727,20150825,-21.6
20150728,20150826,-21.1
20150729,20150827,-20.6
20150730,20150828,-20.1

[Sigmetnow]

Pacific news: Either side of Hawaii.  Link has a short radar clip.

@EricBlake12: Historic central/eastern Pacific outbreak- 3 major hurricanes at once for the first time on record! #ElNino #climate http://t.co/t4fdIZwhOO

https://twitter.com/ericblake12/status/637729647246094336

[jai mitchell]

better pic

[Sigmetnow]

So all this is happening:
1) @1207 above

@EricBlake12: Historic central/eastern Pacific outbreak- 3 major hurricanes at once for the first time on record!

2) Weird Weather:  https://forum.arctic-sea-ice.net/index.php/topic,323.msg62343.html#msg62343

According to the National Hurricane Center, Fred is just the fourth Atlantic named storm to form east of 19 degrees West longitude.

3) Weird Weather:  https://forum.arctic-sea-ice.net/index.php/topic,323.msg62345.html#msg62345

Unusually deep trough & low-pressure (< 980 mb) over Alaska & Yukon Canada.  Snow, freezing temps next several days

It appears the atmosphere is rather upset at the moment. 

[AbruptSLR]

The first image shows the Albany 850-hPa Wind Anom forecast from August 30 to Sept 6 2015, showing that we are now entering a moderate WWB period; which is confirmed by the second attached image that shows the Earth 850-hPa Wind & TPW Map for August 30 2015.  The third image shows a NASA satellite photo for August 30 2015, which confirms that a moderate SPCZ also exits at the moment.

The fourth image issued today by the BoM, shows that the 30-day moving average SOI has drifted down to -20.3:

[AbruptSLR]

As DO may still be out & about I provide the following NOAA Nino data showing that the Nino 3.4 is now +2.2, and the Nino 1+2 is increasing rapidly:

                      Nino1+2      Nino3        Nino34        Nino4
 Week           SST SSTA     SST SSTA   SST SSTA   SST SSTA

 29JUL2015      23.9 2.7     27.4 2.1     28.8 1.7     29.7 1.0
 05AUG2015     23.6 2.6     27.6 2.3     28.9 1.9     29.6 0.9
 12AUG2015     22.8 2.0     27.3 2.2     28.9 2.0     29.6 0.9
 19AUG2015     22.4 1.7     27.2 2.2     28.9 2.1     29.7 1.1
 26AUG2015     22.6 2.0     27.3 2.3     29.0 2.2     29.7 1.1

[AbruptSLR]

Both of the attached images were issued today by NOAA.  The first image shows a model estimate of the Eq Pac Subsurface Temp Anom for August 26 2015, showing that while there is still some cool water off the coast of Ecuador, the current pulse of the EKW has surfaced sufficiently to begin raising the Nino 1+2 index.

The second image shows the Eq. Pac. Upper Ocean Heat Anom Evolution, showing that the current EKW pulse is now entering a trough phase and may (or may not) enter another more active down-welling phase circa October 2015

[AbruptSLR]

The following linked reference provides some more insights on the growing ENSO risks with continued global warming; however, it concludes with a call for still further research on this complex matter:

Wenju Cai, Agus Santoso, Guojian Wang, Sang-Wook Yeh, Soon-Il An, Kim M. Cobb, Mat Collins, Eric Guilyardi, Fei-Fei Jin, Jong-Seong Kug, Matthieu Lengaigne, Michael J. McPhaden, Ken Takahashi, Axel Timmermann, Gabriel Vecchi, Masahiro Watanabe & Lixin Wu (2015), "ENSO and greenhouse warming", Nature Climate Change, Volume: 5, Pages: 849–859, doi:10.1038/nclimate2743


http://www.nature.com/nclimate/journal/v5/n9/full/nclimate2743.html


Abstract: "The El Niño/Southern Oscillation (ENSO) is the dominant climate phenomenon affecting extreme weather conditions worldwide. Its response to greenhouse warming has challenged scientists for decades, despite model agreement on projected changes in mean state. Recent studies have provided new insights into the elusive links between changes in ENSO and in the mean state of the Pacific climate. The projected slow-down in Walker circulation is expected to weaken equatorial Pacific Ocean currents, boosting the occurrences of eastward-propagating warm surface anomalies that characterize observed extreme El Niño events. Accelerated equatorial Pacific warming, particularly in the east, is expected to induce extreme rainfall in the eastern equatorial Pacific and extreme equatorward swings of the Pacific convergence zones, both of which are features of extreme El Niño. The frequency of extreme La Niña is also expected to increase in response to more extreme El Niños, an accelerated maritime continent warming and surface-intensified ocean warming. ENSO-related catastrophic weather events are thus likely to occur more frequently with unabated greenhouse-gas emissions. But model biases and recent observed strengthening of the Walker circulation highlight the need for further testing as new models, observations and insights become available."

[deep octopus]

Thanks for updating the SST numbers ASLR. Busy morning on my end. Attached is the SST anomaly chart by OSPO for August 31. It shows the small zone of cool water between the Galapagos and Ecuador, but I think this will dissipate as the EKW surfaces.

[AbruptSLR]

Per the attached plot issued today by the BoM, the 30-day moving average SOI has drifted down to -20.4:

[AbruptSLR]

The four accompanying plots were all issued by the BoM (with the first two showing data through the week ending August 30 2015 and the second two forecasts issued on August 30 2015).

The first image shows that the Nino3.4 index has moved up to +2.02.

The second image shows that the IOD index is above +0.4.

The third image shows the POAMA Nino 3.4 forecast showing 100% probability that the El Nino event will last through the end of 2015.

The fourth image shows that the POAMA IOD forecast showing a strong chance that it will remain above +0.4 for the rest of this year; which increases the chance of a strengthening El Nino.

Finally, the following is an extract from the BoM ENSO Overview for September 1 2015:

"The 2015 El Niño is now the strongest El Niño since 1997–98. The tropical Pacific Ocean and atmosphere are fully coupled, with sea surface temperatures well above El Niño thresholds, consistently weak trade winds, and a strongly negative Southern Oscillation Index. Weekly tropical Pacific Ocean temperature anomalies (i.e. difference from normal) in the central Pacific are now at their highest values since 1997–98, though still remain more than half a degree below the peak observed during 1997–98.
Most international climate models surveyed by the Bureau of Meteorology indicate the tropical Pacific will continue to warm, with the largest anomalies occurring later in the year. Typically, El Niño peaks during the late austral spring or early summer, and weakens during late summer to autumn. The 2015 event has, so far, been following a normal El Niño life cycle.
While the Indian Ocean as a whole has been at near-record temperatures, the Indian Ocean Dipole (IOD) index has been at or above +0.4 °C for the past four weeks. To be considered a positive event, the IOD would need to remain at or above +0.4 °C through September. Three of the five international models surveyed by the Bureau of Meteorology indicate a positive IOD event is likely during spring."
 

[AbruptSLR]

The four attached plots of the Nino 1, 2, 3 & 4 indices, respectively, were issued today by the BoM for the week ending August 30 2015.  These plots support the idea that the current El Nino event continues to strengthen.

[AbruptSLR]

The two attached plots of the BoM's Summary of model forecasts for the Nino 3.4 index, issued August 30 2015, for the months of November 2015 and January 2016, repectively.  I note that while the average of all of the forecasts have the Nino 3.4 index decreasing from Nov 2015 to Jan 2016; the NASA model has the Nino 3.4 index continuing to increase until January 2016.

[Tor Bejnar]

The NSW/NCEP/CPC graphs “CFSv2 forecast Niño3.4 SST anomalies” [both versions] that update daily near the top of this page (reply #1001) indicate a current Niño3.4 SST anomaly of about 1.8.  Both the BoM graph (see Sept. 1-reply #1036) and the NOAA data (see Aug. 31-reply #1031) indicate a value of 2.2.  Can someone explain how the different organizations come up with their (different or same) values? (or otherwise straighten me out!)

[AbruptSLR]

The NSW/NCEP/CPC graphs “CFSv2 forecast Niño3.4 SST anomalies” [both versions] that update daily near the top of this page (reply #1001) indicate a current Niño3.4 SST anomaly of about 1.8.  Both the BoM graph (see Sept. 1-reply #1036) and the NOAA data (see Aug. 31-reply #1031) indicate a value of 2.2.  Can someone explain how the different organizations come up with their (different or same) values? (or otherwise straighten me out!)

First, as you will note, the CFSv2 forecasts graphs have dates for the range of input data into their models that are one to two weeks prior to the current date; thus in a strengthening event like we have now you would always expect the graphs to show observed data that are lower than the current observed data.

Second, the following linked BBC article contains a nice summary of our current ENSO situation, including the influence of clouds near the equatorial international dateline (see the attached BoM plot from today, showing high cloud cover in this area):

http://www.bbc.com/news/science-environment-34120583

[AbruptSLR]

Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved up to -19.8:

[Sigmetnow]

Hurricane Kilo Crosses Dateline, Becomes Typhoon

The storm formerly known as Hurricane Kilo is now Typhoon Kilo. Well, sort of. The storm is trapped somewhere in the space-time-storm continuum, halfway between typhoon and hurricane, today and tomorrow, eastern and western Pacific.

http://www.climatecentral.org/news/hurricane-kilo-typhoon-19400

[AbruptSLR]

The attach plot by the U. at Albany 5S-5N 850-hPa Wind Anom forecast thru Sept 9 2015, shows both that the recent WWB was stronger than forecast (giving a boost to another pulse of the EKW) and that sustained westerlies are forecast through Sept. 9 on both sides of the International Dateline.

[AbruptSLR]

Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved up to -17.9:

[AbruptSLR]

Per the attached TAO plots of observed data:

The first image shows that the Eq. Pac. Subsurface Temp Anom. in the Eastern Pacific exceeded 7C on August 31 2015 (which exceeded NOAA's model forecast).

The second image for August 30 2015 shows that the sustained westerly anomaly need the International Dateline was anomalously high which should support yet another pulse of EKW in the coming months.

[AbruptSLR]

If you want to get into the weeds of ENSO behavior, the you can visit the website of Dr Jin-Yi Yu, of UC Irvine, at the following link:

http://www.ess.uci.edu/~yu/


See also:
http://www.ess.uci.edu/~yu/PDF/Yu%20et%20al.2015.JCLI.pdf

http://www.ess.uci.edu/~yu/CLOUD/

[Lord M Vader]

The weather seems difficult for the models to handle right now. However, CPC NOAA hints of a distinct possibility of a new WWB which, at least for now, seems to be weak and located west of Dateline as MJO might picking up some strength.

Somethimg we should expect given the current El Niño is a weak or non-existent MJO. IF, and there need to be an IF, the models are underestimating things, then we might see a reinforcing of the current EKW, more surfacing, rising SSTA in Niño 3.4-area and maybe also a more pronounced cooling of the Western Pacific. That would also increase the possibility for our current El Niño to rival the 1997-1998 event.

See more here: http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml

//LMV

[AbruptSLR]

Per the attached plot issued today by the BoM, the 30-day moving average SOI has moved up to -16.8:

[James Lovejoy]

NOAA's latest MEI puts 2015 at just under the 'super El Nino values.  (For Now).

http://www.esrl.noaa.gov/psd/enso/mei/

Compared to last month, the updated (July-August) MEI has increased significantly by 0.39 standard deviations to +2.37, or the 2nd highest ranking, surpassed only in 1997 at this time of year. This new peak value of the current event ranks third highest overall at any time of year since 1950, with 1982-83 and 1997-98 remaining in a 'Super El Niño' club of their own (for now), with peak values around +3 standard deviations.

[AbruptSLR]

NOAA's latest MEI puts 2015 at just under the 'super El Nino values.  (For Now).

http://www.esrl.noaa.gov/psd/enso/mei/

Compared to last month, the updated (July-August) MEI has increased significantly by 0.39 standard deviations to +2.37, or the 2nd highest ranking, surpassed only in 1997 at this time of year. This new peak value of the current event ranks third highest overall at any time of year since 1950, with 1982-83 and 1997-98 remaining in a 'Super El Niño' club of their own (for now), with peak values around +3 standard deviations.

Per the attached MEI plot, one way to think of our current event is that it is lagging behind the 97-98 event; however, in my opinion a more realistic way to view our current event is that it is far ahead of the 82-83 event and may very likely peak in the Dec to Jan. timeframe.

[AbruptSLR]

Per the attached plot issued today by BoM, the 30-day moving average SOI has moved up to -15.6: