Support the Arctic Sea Ice Forum and Blog

Author Topic: 2015 El Niño?  (Read 764594 times)

Csnavywx

  • Grease ice
  • Posts: 572
    • View Profile
  • Liked: 82
  • Likes Given: 2
Re: 2015 El Niño?
« Reply #650 on: May 14, 2015, 02:50:01 AM »
Large warm pool extensions actually FAVOR westerly wind bursts: https://www.whoi.edu/fileserver.do?id=100104&pt=2&p=119089

A weak temperature gradient longitudinally across the equator is also what you want to weaken the trades further east and help sustain Nino conditions. The weaker the gradient, the better.

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #651 on: May 14, 2015, 04:06:11 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has dropped down to -12.7
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

bigB

  • Frazil ice
  • Posts: 481
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2015 El Niño?
« Reply #652 on: May 14, 2015, 06:15:43 AM »
Large warm pool extensions actually FAVOR westerly wind bursts: https://www.whoi.edu/fileserver.do?id=100104&pt=2&p=119089

A weak temperature gradient longitudinally across the equator is also what you want to weaken the trades further east and help sustain Nino conditions. The weaker the gradient, the better.

Csnavywx,

Please see the following link, which leads to an article from NOAA's ENSO blog regarding the importance of an enhanced SST gradient to El Nino:

http://www.climate.gov/news-features/blogs/enso/what%E2%80%99s-hold-el-ni%C3%B1o

Sleepy

  • Guest
Re: 2015 El Niño?
« Reply #653 on: May 14, 2015, 07:36:56 AM »
The role of the western Pacific maybe tends to be forgotten at times?
Further reading to the importance of the temperature gradient which is a fundamental part of El Nino, by a link to Jack Bjerknes.
I think I've posted it earlier.
http://iridl.ldeo.columbia.edu/maproom/ENSO/New/bjerknes.html
Quote
Bjerknes associated the feedback loop of the oceanic and atmospheric circulation over the tropical Pacific as a "chain reaction", noting that "an intensifing Walker Circulation also provides for an increase of east-west temperature contrast that is the cause of the Walker Circulation in the first place." Bjerkness also found that the interaction could operate in the opposite: a decrease in the equatorial easterlies diminishes the supply of upwelling cold water and the lessened east-west temperature gradient causes the Walker Circulation to slow down. He thus provided an explanation for the association of the low phase of the Southern Oscillation with El Niño as well as the association of the high phase with normal cold state of the eastern Pacific.

Normally during a fully coupled El Nino there are colder anomalies in the western Pacific. Last year there were, simply put, too much warm water to produce a fully coupled El Nino. Like the article that Bigb linked to concludes. There were a nice explanation by Mike Crimmins in a podcast last October.
http://www.climas.arizona.edu/sites/default/files/SW_ClimatePodcast_10.23.2014_TRANSCRIPT.pdf
Quote
But for the most, the warm water has been there and the atmosphere has failed to respond. Most likely because there isn't a nice temperature gradient. When you have these Kelvin waves go from the West Pacific to the East Pacific, you typically have cool water then in the West Pacific and then warmer water, which is reverse of what it normally is. That temperature gradient it what the winds would respond to. But there is so much warm water across the whole pacific, that the West Pacific has just been giving bursts of warm water and it is still warm enough that you aren't getting the gradient.

JAXA report of the Nino West region attached.

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #654 on: May 14, 2015, 05:06:08 PM »
With all of the excellent discussion about the importance of a SSTA gradient from the Western to Eastern Equatorial Pacific, I provide the first image for May 14 2015 that shows that this gradient is currently being formed; which raises the prospect for that full oceanic-atmospheric couple may develop sooner rather than later.

Next, I provide the following Cyclocane forecast extract indicating a possible new TD could form near 0.9N 174.7E:

"TROPICAL DISTURBANCE SUMMARY:
      (1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 0.9N 174.7E IS NOW LOCATED NEAR 0.9N 173.5E, APPROXIMATELY 385 NM SOUTH-SOUTHEAST OF MAJURO. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A BROAD CIRCULATION AREA WITH MOSTLY DISORGANIZED FLARING CONVECTION. UPPER LEVEL ANALYSIS INDICATES THE DISTURBANCE IS IN A MARGINAL ENVIRONMENT WITH LOW TO MODERATE (10-20 KNOT) VERTICAL WIND SHEAR AND WEAK DIVERGENT OUTFLOW. NUMERIC MODELS HAVE BACKED OFF SIGNIFICANTLY ON NEAR TERM DEVELOPMENT. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 MB. DUE TO THE MARGINAL UPPER LEVEL ENVIRONMENT, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS LOW."

The second attached image issued by NOAA today shows that the Eq Pac Upper Ocean Heat Anom is still slowly decreasing.

The third image shows the NCPE MJO forecast from May 14 to 28 2015; indicating that some small level of MJO activity may occur just west of the international dateline in the next week.

The fourth image shows the U of Albany 5S-5N 850 hPa Wind Anom forecast from May 14 to 21 2015, showing a reduction in projected WWB activity (unless a TD develops near the dateline in the next day or two, per Cyclocane).

Edit: I neglected to mention that the Long Paddock Station daily SOI for May 14 2015 was:
-27.70
« Last Edit: May 14, 2015, 05:24:11 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

Csnavywx

  • Grease ice
  • Posts: 572
    • View Profile
  • Liked: 82
  • Likes Given: 2
Re: 2015 El Niño?
« Reply #655 on: May 14, 2015, 06:39:19 PM »
Large warm pool extensions actually FAVOR westerly wind bursts: https://www.whoi.edu/fileserver.do?id=100104&pt=2&p=119089

A weak temperature gradient longitudinally across the equator is also what you want to weaken the trades further east and help sustain Nino conditions. The weaker the gradient, the better.

Csnavywx,

Please see the following link, which leads to an article from NOAA's ENSO blog regarding the importance of an enhanced SST gradient to El Nino:

http://www.climate.gov/news-features/blogs/enso/what%E2%80%99s-hold-el-ni%C3%B1o

I think we may be talking past each other. I am speaking in terms of actual mean temperatures. They're talking in terms of anomalies and the resultant anomalous wind:

Quote
(3) If SST anomalies are being compared (as is the case in this post), then the stronger and weaker winds refer to the anomalous winds. 

Which is really (in most cases) just a weakening of the trades. Strong anomalies, of course, can indicate an actual reversal.

As the warm pool extends eastward and elongates, it makes WWBs more likely (per the paper anyways) and thus the fledgling Nino effectively loads the dice in its favor.


ghoti

  • Grease ice
  • Posts: 767
    • View Profile
  • Liked: 12
  • Likes Given: 15
Re: 2015 El Niño?
« Reply #656 on: May 14, 2015, 06:58:24 PM »
Looking at the CDAS sea surface temperature anomaly graphic posted by AbruptLSR above I'm struck with the thought - What would the major  1998 El Nino have looked like if we used the 1981-2010 climatology to calculate the anomaly?

Problem with the moving baseline is that it really down plays the temperatures we now experience and will into the future.

Jester Fish

  • New ice
  • Posts: 34
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2015 El Niño?
« Reply #657 on: May 14, 2015, 08:31:15 PM »
From today's NOAA (USA) ENSO Blog:

Speaking of typical events, though – this is not one of them. As you can see below, it is unusual for sea surface temperatures in the Niño3.4 region to start off warm in the winter and then continue to be warm through the spring and summer. In the 60-year record, only one El Niño event, in 1986-1987, had similar behavior. The evolution and strength of this event might be a little easier to predict if it were starting at a more typical time of year.




http://www.climate.gov/news-features/blogs/enso/may-2015-enso-forecast-will-el-ni%C3%B1o-be-overachiever-or-peaked-high-school

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #658 on: May 14, 2015, 11:06:34 PM »
As this is a critical timeframe for determining just how strong the current El Nino event will become, I provide the first two NOAA images for May 8 2015, showing both the Eq. Pac. Subsurface Temp., and Temp. Anom., respectively, both indicating relatively good conditions for further  possible El Nino strengthening.

Also, I provide the third attached image of NASA's Jason-2 April 25 2015 sea level anom, also showing a relatively strong EKW.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

JayW

  • Grease ice
  • Posts: 607
    • View Profile
  • Liked: 226
  • Likes Given: 292
Re: 2015 El Niño?
« Reply #659 on: May 15, 2015, 01:09:31 AM »
Apologies if my post was poorly worded. I'm very much a novice, but a weather lover.  Certainly not trying to be misleading, just eager to learn.  :) hopefully I'm not too much in error.

 I tried to use the phrase "proper gradient" because it seems like it's a very delicate balance between the water temperatures in the east and west Pacific that govern ENSO.  Something that has puzzled me is that while global oceans have generally risen in temperatures, this hasn't seemed to manifest itself nearly as strongly in the equatorial Pacific.

http://www.cpc.ncep.noaa.gov/products/GODAS/ocean_briefing.shtml


It also seems that any warming in the last 30 years has occurred mainly west of the dateline. 
I imagine this affects the base climatology and anomaly magnitude.

http://www.esrl.noaa.gov/psd/map/clim/sst.shtml

So if the western Pacific is indeed warning faster than the east Pacific, it seems that pool of 28°C water in the west Pacific will be ever expanding.  With such a large area prone to deep convection, I'm simply wondering if that is playing a role in the full ocean-atmosphere coupling having difficultly taking firm hold.  I keep imagining this convection acting like a vacuum, trying to pull air in from all sides.  So every time we get the bulk of convection trying to move to the dateline and east of it, the seething Pacific warm pool draws it back west, and the easterly trades try to ramp back up and dissipate the heat, but can't make its mind up either.


http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/enso.shtml

Attached is anomalous OLR from MJJ 1997. Noting the negative anomalies dominated east of the dateline.
http://www.esrl.noaa.gov/psd/data/composites/day/

In my post #651, I was trying to compare 1997 to current conditions, and highlight that the west Pacific was cooler at this time in 1997 than now, preceding that very strong event.  We are certainly seeing the warm water move east, but coupling seems to come in fits and starts.  I keep wondering if things keep ratcheting up until the warm pool gives in.  But how long do we have to wait?

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/enso.shtml

I certainly agree that the warmth in the west Pacific is driving these Kelvin waves.  That's why I think even if the current El Niño conditions relax, well likely see another serious of Kelvin waves and end up back where we are.  But I've learned that EKWs are just one part of the puzzle, I believe it's the mechanism that basically affects upwelling along South America, opening the door for warming, but only if it can successfully alter the walker circulation and "trap" the warmth in the east Pacific.

As every El Niño is unique, I think the wait and see approach of Dr Klaus Wolter is warranted in regards to strength.  However, I wonder about the possibility of this being a more protracted event, perhaps not of the highest amplitude, but of long duration. And I'm not sure which is scarier, very strong or long lasting.  :)

Apologies for any typos and rambling, my brain moves faster than the fingers, happy to clarify any of my points.

Second attachment is the latest region 3.4 plumes cost of the UKMO
http://www.metoffice.gov.uk/research/climate/seasonal-to-decadal/gpc-outlooks/el-nino-la-nina
"To defy the laws of tradition, is a crusade only of the brave" - Les Claypool

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #660 on: May 15, 2015, 03:50:15 AM »
First, the attached plot issued today by the BoM indicates that the 30-day moving average SOI has dropped down to -13.4:


Second, I would like to note to JayW that the Southern Ocean has received more than its share of Ocean Heat Uptake, and as the South Pacific is a large body of water it contributes more heat content to the Southern Ocean than either the Atlantic, or the Indian, Oceans.  Furthermore, the Southern Ocean interconnects the Pacific, Atlantic and the Indian Oceans, and multi-decadal oscillations can teleconnect energy through all of these interconnected oceans.
« Last Edit: May 15, 2015, 10:51:19 AM by AbruptSLR »
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

JayW

  • Grease ice
  • Posts: 607
    • View Profile
  • Liked: 226
  • Likes Given: 292
Re: 2015 El Niño?
« Reply #661 on: May 15, 2015, 04:46:56 AM »
ASLR,
   I agree wholeheartedly.  Hopefully I can clarify. :)  when looking at the long term time series of the various areas of the globe, the signs of global warming seems so evident just about everywhere, but not so much in the equatorial Pacific time series.  If (and that's a big, speculative if) the areas around the ENSO regions are warming faster than the equatorial Pacific, what effect does that have? Is there a limit to how much heat the equatorial Pacific can physically hold, and that heat is dispersed through any number of processes?

  And as you mentioned, the southern ocean has absorbed its share of heat, what happens if this heat starts getting dumped into the ENSO regions?   I guess I'm just speculating about ENSO behavior as the oceans warm further.  Hope I'm not misinterpreted,  :) I gravely worry about the vast amounts of heat the ocean is absorbing, and it's effects on climate variability, in this case on ENSO.  Sometimes it feels like we are living in an experiment, a sadistic experiment with enormous consequences. 

My questions are mostly musings, but I enjoy the feedback this forum provides.  It's hard to find people in my everyday life that I can discuss this stuff with.

Best,
JayW
"To defy the laws of tradition, is a crusade only of the brave" - Les Claypool

bigB

  • Frazil ice
  • Posts: 481
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2015 El Niño?
« Reply #662 on: May 15, 2015, 04:53:09 AM »
ghoti,

The NOAA Interpolated OLR image JayW provided in his post gave me an idea. The attached image  shows a comparison between the NCEP/NCAR Reanalysis Pacific Basin SSTA charts for May 12th, 1997 (top), and May 12th, 2015 (bottom). Both charts were produced using the same climatological base period (1981-2010). This isn’t quite the same as the CDAS SSTA chart, but in reality, SST's in the Pacific Basin have only increased slightly since 1997. However, that (the slight increase in SST's since 1997) may soon be changing. ASLR or DO may be able to further elaborate as they are both much more qualified on that subject than I am.

EDIT: I seem to have timed my post well, regarding JayW's latest post (good to see you back by the way JayW)!

Csnavywx,

We were indeed talking past each other.
« Last Edit: May 15, 2015, 05:05:04 AM by bigB »

Bruce Steele

  • Young ice
  • Posts: 2519
    • View Profile
  • Liked: 753
  • Likes Given: 41
Re: 2015 El Niño?
« Reply #663 on: May 15, 2015, 05:33:41 AM »

Michael Hauber

  • Nilas ice
  • Posts: 1115
    • View Profile
  • Liked: 168
  • Likes Given: 16
Re: 2015 El Niño?
« Reply #664 on: May 15, 2015, 05:58:28 AM »
ASLR,
   I agree wholeheartedly.  Hopefully I can clarify. :)  when looking at the long term time series of the various areas of the globe, the signs of global warming seems so evident just about everywhere, but not so much in the equatorial Pacific time series.  If (and that's a big, speculative if) the areas around the ENSO regions are warming faster than the equatorial Pacific, what effect does that have? Is there a limit to how much heat the equatorial Pacific can physically hold, and that heat is dispersed through any number of processes?

  And as you mentioned, the southern ocean has absorbed its share of heat, what happens if this heat starts getting dumped into the ENSO regions?   I guess I'm just speculating about ENSO behavior as the oceans warm further.  Hope I'm not misinterpreted,  :) I gravely worry about the vast amounts of heat the ocean is absorbing, and it's effects on climate variability, in this case on ENSO.  Sometimes it feels like we are living in an experiment, a sadistic experiment with enormous consequences. 

My questions are mostly musings, but I enjoy the feedback this forum provides.  It's hard to find people in my everyday life that I can discuss this stuff with.

Best,
JayW

I think that the climate is becoming more La Nina like on average.  The nino 3.4 region is not warming up, and so by comparison to the rest of the globe is becoming cooler.  The question is whether this is a natural variation, perhaps a result of stronger cool phases of the PDO in the 70s and recently.  Or whether it is a response to Co2 warming.  Co2 warming has been frequently predicted to lead to el nino like conditions due to an expansion of the tropical zone and the Hadley cell.  This would shift the subtropical high pressure belt away from the equator.  As this high pressure belt is one of the primary forces behind the equatorial trade winds this would weaken them and make it easier for el nino conditions to form.

However at the same time as this is occurring we are seeing that the surface of the ocean is warming up significantly faster than the subsurface.  The primary reason why the cool tongue exists is because of significant upwelling of cooler water from the subsurface.  As the subsurface is not warming as fast as the surface this upwelling influence becomes more powerful, and so the nino regions do not warm as fast as the rest of the Pacific.

In a previous post you mention 28 degrees as a threshold for deep convection.  I believe that this is not a hard and fast number, but a threshold relative to the rest of the equatorial regions.  As the planet warms this threshold will increase.  Basically whichever parts of the tropical regions are warmer compared to the rest of the tropics will support deep convection, and whichever parts are cooler will not.

On the southern ocean, the primary reason why the southern ocean is accumulating a lot of heat is because this is one of the primary regions for surface waters to mix with the deep ocean.  This heat will then mix reasonably directly along the humboldt current into the ENSO regions, but the ocean is vast and the heat is being diluted a lot.  The warming rate of these waters is much slower than the surface so these waters are still becoming cooler in comparison.  It is only when substantial slow downs in Co2 emissions and the rate of warming starts to level off that the subsurface will have a chance to catch up to the surface.

To me it is not so much a case that the heat being dumped in the deep ocean will come back to haunt us.  It is more the case that the deep ocean is a garbage dump for heat, and as it slowly fills up it will take less and less of the surface heat away.  Perhaps it is only a semantic difference.

On the topic of why the atmosphere didn't fully respond last year I'm not convinced that the east-west gradient was the primary culprit.  We saw a lot of warm water near the dateline in say April last year.  This results in a shift of tropical convection away from the SE ASian region out into the central Pacific.  This convection means westerly winds in the equator for cyclones/hurricanes in both NH and SH.  We did see several significant bursts of typhoon/hurricane activity out in the Pacific.  But two things happened.  First the typhoons/hurricanes kept moving towards the west and north, which reduces the assistance these systems give to the developing el nino.  This is in contrast to the South Pacific cyclone seasons in both 13/14 and 14/15 which saw much less westerly movement than normal, and very strong westerly activity during the peak cyclone season.  However being east coast Australian I'm a keen watcher of the SW Pacific cyclones and haven't watched the NH season nearly so much so I'm not sure if that is normal even in an el nino year.  I note that the current batch of typhoons is still mostly moving towards the west. 

The second thing was that convection always seems to happen in batches.  You see a burst of activity for a week or two and then a couple quiet weeks.  During the quiet weeks last year the trade winds were above average.  I suspect the strong cool water in the SE Pacific may have had a role in this.  My thinking being that this intensifies the High pressure belt in this region, and when tropical convection is not active this results in the high pressure pushing trade winds across the equator into the NH monsoon being the most important factor controlling the trade wind strength.  In contrast while we had a SH monsoon the cross equatorial trade winds are coming from the NH which has had a strong warm PDO pattern and much weaker NE high pressure cell since late 2013.
Climate change:  Prepare for the worst, hope for the best, expect the middle.

wili

  • Young ice
  • Posts: 3342
    • View Profile
  • Liked: 602
  • Likes Given: 409
Re: 2015 El Niño?
« Reply #665 on: May 15, 2015, 06:31:53 AM »
"climate is becoming more La Nina like"

In other words, to paraphrase the common Game of Thrones motto:

Winter is Dying!

(Hat tip to rs)
"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #666 on: May 15, 2015, 11:41:57 AM »
ASLR,
   I agree wholeheartedly.  Hopefully I can clarify. :)  when looking at the long term time series of the various areas of the globe, the signs of global warming seems so evident just about everywhere, but not so much in the equatorial Pacific time series.  If (and that's a big, speculative if) the areas around the ENSO regions are warming faster than the equatorial Pacific, what effect does that have? Is there a limit to how much heat the equatorial Pacific can physically hold, and that heat is dispersed through any number of processes?

  And as you mentioned, the southern ocean has absorbed its share of heat, what happens if this heat starts getting dumped into the ENSO regions?   I guess I'm just speculating about ENSO behavior as the oceans warm further.  Hope I'm not misinterpreted,  :) I gravely worry about the vast amounts of heat the ocean is absorbing, and it's effects on climate variability, in this case on ENSO.  Sometimes it feels like we are living in an experiment, a sadistic experiment with enormous consequences. 

My questions are mostly musings, but I enjoy the feedback this forum provides.  It's hard to find people in my everyday life that I can discuss this stuff with.

Best,
JayW

While I do not have time to respond properly, I provide the following two older references about ENSO & global teleconnections through the Southern Ocean:

Peterson, R. G., and W. B. White (1998), Slow oceanic teleconnections linking the Antarctic Circumpolar Wave with the tropical El Niño-Southern Oscillation, J. Geophys. Res., 103(C11), 24573–24583, doi:10.1029/98JC01947.

http://onlinelibrary.wiley.com/doi/10.1029/98JC01947/abstract

Abstract: "A case study for the period 1982–1994 shows that a major source for the Antarctic Circumpolar Wave is in the western subtropical South Pacific, where interannual anomalies in sea surface temperature (SST) and precipitable water (PrWat) form. Once established, these interannual anomalies, in tandem with anomalies in sea level pressure (SLP), move south toward the Southern Ocean. The system then migrates east around the globe through a combination of oceanic advection with the Antarctic Circumpolar Current and ocean-atmosphere coupling. The coincidence of interannual anomalies in SST, SLP, and PrWat indicates the extratropical ocean and atmosphere are tightly linked on these timescales. Large portions of the interannual SST anomalies branch advectively northward into the South Atlantic and Indian Oceans, ultimately reaching the tropics in each basin some 6–8 years after appearing in the low-latitude Pacific. This constitutes a slow, oceanic teleconnection that is unique in climate dynamics, made possible by the continuity of Earth's oceans via the Southern Ocean. In the tropical Indian Ocean these interannual anomalies move east and arrive at the Indo-Pacific transition in advance of the trans-Pacific propagation of the respective El Niño-Southern Oscillation (ENSO) phases. The interannual SST and PrWat anomalies that appear in the subtropical South Pacific are directly linked with the ENSO cycle on the equator through anomalous vertical convection and a regional overturning cell in the troposphere, the same cell that initiates fast planetary waves in the atmosphere that carry ENSO signals around the southern hemisphere on much shorter timescales."


White, W. B., S.-C. Chen, R. J. Allan, and R. C. Stone, Positive feedbacks between the Antarctic Circumpolar Wave and the global El Niño–Southern Oscillation Wave, J. Geophys. Res., 107(C10), 3165, doi:10.1029/2000JC000581, 2002.

http://onlinelibrary.wiley.com/doi/10.1029/2000JC000581/abstract

Abstract
"Atmospheric and oceanic teleconnections link the Antarctic Circumpolar Wave (ACW) in the Southern Ocean [White and Peterson, 1996] and the global El Niño-Southern Oscillation (ENSO) wave (GEW) in the tropical Indo-Pacific Ocean [White and Cayan, 2000], both signals characterized by eastward phase propagation and 3- to 5-year- period variability. We extend the tropical standing mode of ENSO into the extratropics by regressing the Niño-3 sea surface temperature (SST) index against sea level pressure (SLP) anomalies over the globe, finding the Pacific-South America (PSA) pattern in SLP anomaly [Cai and Baines, 2001] straddling Drake Passage in the Southern Ocean. The amplitude of this PSA pattern is ∼1/3 that of the ACW in this domain and thus cannot be considered its principal driver. On the other hand, suppressing the tropical standing mode of ENSO in interannual ST (surface temperature) and SLP anomalies over the globe allows the GEW to be observed much more readily, whereupon its eastward phase propagation across the Warm Pool is found to remotely force the ACW in the eastern Pacific and western Atlantic sectors of the Southern Ocean through atmospheric teleconnections [Sardeshmukh and Hoskins, 1988] which propagate along with it. Subsequently, the ACW propagates this imposed GEW signal throughout the remainder of the Southern Ocean as a coupled wave in covarying ST and SLP anomalies, whereupon entering the Indian sector 1.5 to 2.5 years later it spawns a northern branch which takes another 1.5 to 2.5 years to propagate the ACW signal equatorward into the Warm Pool south of Indonesia. There it interferes constructively with the GEW. Thus the two forms of teleconnection, one fast and directed from the tropics to the high southern latitudes via the atmosphere and the other slow and directed from the high southern latitudes to the tropics via the ocean, complete a global circuit of 3- to 5-year duration that reinforces both the ACW and GEW and influences the tropical standing mode of ENSO."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

JayW

  • Grease ice
  • Posts: 607
    • View Profile
  • Liked: 226
  • Likes Given: 292
Re: 2015 El Niño?
« Reply #667 on: May 15, 2015, 12:08:32 PM »
BigB,

Thanks!  It was a long winter up here, seems like I was tracking snow 24/7.  Last of it finally melted just a few weeks ago basically.  But I've been following along, just haven't had the time, I hope to contribute more that just confusion   :) , now that my weather has become kinda boring.


Michael Hauber,

Appreciate you taking the time to respond, and comprehensively, you've given me lots of good stuff to think about. Thanks for touching on the 28°C I made, I've been wondering if the threshold for deep convection was relative or a static figure.

 You noted the behavior of tropical cyclones. The "typhoon rule" (I wonder if you have a similar rule) suggests that typhoons that recurve near Japan (generally indicative of a trough over Japan) *normally* translate to "troughiness" in the eastern United States ~7-10 later.  Typhoons that travel over the Philippines and into China would generally "teleconnect" to east coast US ridging.  We saw lots of recurving storms this past winter.  :D

In some of my reading, apologies for not having anything to link to, I've seen it suggested that the ITCZ shifts away from the hemisphere with the higher sea ice anomaly.  This seems like a "third rail" but I figured I'd float it out there, gets some more points of view on it.  But it seems like you are similarly watching for recurving typhoons, just in the other hemisphere.  Fun to see the differences between the hemispheres.

I would say that boreal winter weather patterns consistent with a strong positive PDO as well.
First attachment is PDO correlation with temperature. December-March
http://www.esrl.noaa.gov/psd/data/usclimdivs/correlation/
Second attachment is US temperature anomalies this past Dec-Mar
http://www.esrl.noaa.gov/psd/data/composites/day/


ASLR,

Many thanks for the links, I've clearly got homework to do, and I certainly don't mean to put more on your plate. Your patience, and everyone else's with my questions is greatly appreciated.

Thanks so much!!
JayW
"To defy the laws of tradition, is a crusade only of the brave" - Les Claypool

Jim Hunt

  • First-year ice
  • Posts: 6268
  • Don't Vote NatC or PopCon, Save Lives!
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 893
  • Likes Given: 87
Re: 2015 El Niño?
« Reply #668 on: May 15, 2015, 01:58:58 PM »
The latest UK Met Office blog post:

http://blog.metoffice.gov.uk/2015/05/14/el-nino-and-its-impact-on-global-weather/

Quote
Forecast centres around the world have now declared that an El Niño, the most powerful fluctuation in our climate system, has begun in the tropical Pacific. The current outlook suggests that at least a moderate El Nino is likely and there is a risk of a substantial event.

[El Niño] can be linked with poor monsoons in Southeast Asia, droughts in southern Australia, the Philippines and Ecuador, blizzards in the United States, heatwaves in Brazil and extreme flooding in Mexico.

The consequences of El Nino are much less clear for Europe and the UK.
« Last Edit: May 16, 2015, 12:28:13 AM by Jim Hunt »
"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #669 on: May 15, 2015, 04:42:38 PM »
ASLR,

Many thanks for the links, I've clearly got homework to do, and I certainly don't mean to put more on your plate. Your patience, and everyone else's with my questions is greatly appreciated.

Thanks so much!!
JayW

As I only have time for re-posts at the moment, I provide the following two from the Antarctic folder; which indicate both the changes to the ENSO, and impacts of the ENSO, with continuing warming:

First re-post: "Many scientists are concerned that the Earth may be headed towards a Pliocene type of climate this century due to global warming.  The linked reference indicates that changes in cloud cover/albedo for such conditions would rapidly induce the Equatorial Pacific Ocean into a permanent El Nino-like state.  As cloud albedo is a rapid response feedback mechanism, such a change could happen in as little as a few decades from now (say 2040-2050). Permanent El Nino-like conditions would telecommunicate large amounts of heat from the Equatorial Pacific directly to West Antarctica.

N. J. Burls and A. V. Fedorov, (2014), "Simulating Pliocene warmth and a permanent El Niño-like state: the role of cloud albedo", Paleoceanography, DOI: 10.1002/2014PA00264

http://onlinelibrary.wiley.com/doi/10.1002/2014PA002644/abstract

Abstract: "Available evidence suggests that during the early Pliocene (4-5 Ma) the mean east–west sea surface temperature (SST) gradient in the equatorial Pacific Ocean was significantly smaller than today, possibly reaching only 1-2°C. The meridional SST gradients were also substantially weaker, implying an expanded ocean warm pool in low latitudes. Subsequent global cooling led to the establishment of the stronger, modern temperature gradients. Given our understanding of the physical processes that maintain the present-day cold tongue in the east, warm pool in the west and hence sharp temperature contrasts, determining the key factors that maintained early Pliocene climate still presents a challenge for climate theories and models. This study demonstrates how different cloud properties could provide a solution. We show that a reduction in the meridional gradient in cloud albedo can sustain reduced meridional and zonal SST gradients, an expanded warm pool and warmer thermal stratification in the ocean, weaker Hadley and Walker circulations in the atmosphere. Having conducted a range of hypothetical modified cloud albedo experiments, we arrive at our Pliocene simulation, which shows good agreement with proxy SST data from major equatorial and coastal upwelling regions, the tropical warm pool, mid and high latitudes, and available subsurface temperature data. As suggested by the observations, the simulated Pliocene-like climate sustains a robust ENSO despite the reduced mean east–west SST gradient. Our results demonstrate that cloud albedo changes may be a critical element of Pliocene climate and that simulating the meridional SST gradient correctly is central to replicating the geographical patterns of Pliocene warmth.""

Second re-post: "The linked reference indicates (based on data from a snow pit at the South Pole from 1984-2001), that as we enter a positive IPO phase with increased frequency and intensity of El Nino events, we can expect a marked increase in wildfires, that on balance will act as positive feedback mechanism:

Robina Shaheen, Mariana M. Abaunza, Teresa L. Jackson, Justin McCabe, Joël Savarino, and Mark H. Thiemens, (2014), "Large sulfur-isotope anomaly in nonvolcanic sulfate aerosol and its implications for the Archean atmosphere", PNAS, doi: 10.1073/pnas.1406315111.

http://www.pnas.org/content/early/2014/08/01/1406315111

Abstract: Sulfur-isotopic anomalies have been used to trace the evolution of oxygen in the Precambrian atmosphere and to document past volcanic eruptions. High-precision sulfur quadruple isotope measurements of sulfate aerosols extracted from a snow pit at the South Pole (1984–2001) showed the highest S-isotopic anomalies (Δ33S = +1.66‰ and Δ36S = +2‰) in a nonvolcanic (1998–1999) period, similar in magnitude to Pinatubo and Agung, the largest volcanic eruptions of the 20th century. The highest isotopic anomaly may be produced from a combination of different stratospheric sources (sulfur dioxide and carbonyl sulfide) via SOx photochemistry, including photoexcitation and photodissociation. The source of anomaly is linked to super El Niño Southern Oscillation (ENSO) (1997–1998)-induced changes in troposphere–stratosphere chemistry and dynamics. The data possess recurring negative S-isotope anomalies (Δ36S = −0.6 ± 0.2‰) in nonvolcanic and non-ENSO years, thus requiring a second source that may be tropospheric. The generation of nonvolcanic S-isotopic anomalies in an oxidizing atmosphere has implications for interpreting Archean sulfur deposits used to determine the redox state of the paleoatmosphere.""
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #670 on: May 15, 2015, 07:23:37 PM »
For my daily status report I note that:

A) The Long Paddock Station Daily SOI for May 15 2015 was: -33.10

B) The first attached Earth Surface Wind & MSLP Map for May 15 2015, shows that sea level pressure near Tahiti has dropped & and that the possible TD near the equatorial dateline (cited on Cyclocane yesterday) has dissipated.

C) The second attached U of Albany 5S-5N 850 hPa Wind Anom forecast for May 15 to 22 2015, shows a less bullish forecast for WWB activity; probably due to the dissipation of the TD since yesterday.

D) The third & fourth attached images of the May 15 to 29 2015 MJO forecasts for the GFS Ensemble and the NCPE, respectively, indicate that the MJO may (or may not) temporarily strength near the dateline in the next week; which might contribute to convection and cloud cover that might help to develop a stronger Walker Cell El Nino pattern.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #671 on: May 16, 2015, 12:17:54 AM »
The linked NOAA News feature article issued May 14 2015 states: "There’s a 90% chance that the current El Niño will continue through the summer, and forecasters estimate the chance that it will continue through the end of 2015 at greater than 80%. This is a pretty confident forecast. What are the forecasters looking at that gives them such confidence?"

https://www.climate.gov/news-features/blogs/enso/may-2015-enso-forecast-will-el-ni%C3%B1o-be-overachiever-or-peaked-high-school

Random relevant recent plots that support this relatively aggressive forecast include:

The first image shows the BoM Nino 3.4 forecast issued May 12 2015 indicating a strong El Nino beyond the end of 2015.

The second image shows NOAA's Sea Level Anom map for May 8 2015, indicating a strong current EKW.

The third image shows NOAA's 2S-2N Depth to 20C plot thru May 10 2015, indicating a significant increase of the depth of this isotherm offshore of South America.

The fourth image shows NMME SST forecast made in early May 2015 through OND 2015; indicating a strong probability that the current EKW may likely be sustained through the end of 2015.

Edit: The link has been corrected.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

JayW

  • Grease ice
  • Posts: 607
    • View Profile
  • Liked: 226
  • Likes Given: 292
Re: 2015 El Niño?
« Reply #672 on: May 16, 2015, 01:20:16 AM »
Attached are the Niño plume from the ECMWF with May initial conditions. Very bullish particularly in region 3, with many members still appearing to be increasing at the end of the run.
1-region 3.4
2-region 4
3-region 3
Edit: added a 4th attachment, comparison between April (red)  and May (blue) initial conditions for region 3.4
http://www.ecmwf.int/en/forecasts/charts/seasonal/nino-plumes-public-charts-long-range-forecast?public_date=201505&nino_area=3&forecast_type_and_skill_measures=plumes
« Last Edit: May 16, 2015, 01:35:13 AM by JayW »
"To defy the laws of tradition, is a crusade only of the brave" - Les Claypool

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #673 on: May 16, 2015, 03:36:59 AM »
The attached plot was issued today by the BoM & indicates that the 30-day moving average SOI has dropped down to -14.7:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

prokaryotes

  • Frazil ice
  • Posts: 284
    • View Profile
    • Climate State
  • Liked: 47
  • Likes Given: 37
Re: 2015 El Niño?
« Reply #674 on: May 16, 2015, 05:06:19 AM »
Your opinion?

Will a 2015 Arctic sea ice melt season during an El Nino year shatter previous records?
http://climatestate.com/2015/05/15/will-a-2015-arctic-sea-ice-melt-season-during-an-el-nino-year-shatter-previous-records/

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #675 on: May 16, 2015, 03:55:20 PM »
Your opinion?

Will a 2015 Arctic sea ice melt season during an El Nino year shatter previous records?
http://climatestate.com/2015/05/15/will-a-2015-arctic-sea-ice-melt-season-during-an-el-nino-year-shatter-previous-records/

As I think that a lot of warm Pacific Ocean water will enter the Arctic Ocean this year through the Bering Strait, I believe that 2015 will have a record low Arctic Sea Ice extent.

Also, the first image shows the Earth Surface Wind & MSLP map for May 16 2015, showing that while monsoon trough is weakening & the WWB is essentially gone; nevertheless, the SOI is low as the Long Paddock Station Daily SOI for May 16 2015 was: -30.30.

The second image shows the daily Tropical Tidbit Nino 3.4 showing a marked upward movement of this index up to +1.23.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

prokaryotes

  • Frazil ice
  • Posts: 284
    • View Profile
    • Climate State
  • Liked: 47
  • Likes Given: 37
Re: 2015 El Niño?
« Reply #676 on: May 16, 2015, 07:20:15 PM »
As I think that a lot of warm Pacific Ocean water will enter the Arctic Ocean this year through the Bering Strait, I believe that 2015 will have a record low Arctic Sea Ice extent.
Thanks, and the warm water intrusion through the Pacific Ocean, is this connected to El Nino, or can this connection not be made at this point, or does this have to do with The Blob?

prokaryotes

  • Frazil ice
  • Posts: 284
    • View Profile
    • Climate State
  • Liked: 47
  • Likes Given: 37
Re: 2015 El Niño?
« Reply #677 on: May 16, 2015, 09:00:06 PM »
Quote
“If that blob continues, if it stays warm ... and then you add to that El Nino, it may compliment each other and then it may be the year winter is cancelled,” Phillips said
Link

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #678 on: May 17, 2015, 04:24:25 AM »
As I think that a lot of warm Pacific Ocean water will enter the Arctic Ocean this year through the Bering Strait, I believe that 2015 will have a record low Arctic Sea Ice extent.
Thanks, and the warm water intrusion through the Pacific Ocean, is this connected to El Nino, or can this connection not be made at this point, or does this have to do with The Blob?

By the Blob, I guess that you mean the positive PDO; and if so then yes, I think that a positive PDO contributes to warm water in the North Pacific that can then move thru the Bering Strait into the Arctic Ocean.  However, a strong El Nino event can also telecommunicate energy from the tropical Pacific through the atmosphere to Southern Alaska; which are both decrease albedo there and can slowly warm the ocean water (which could then increase the positive PDO, which could then direct warm water thru the Bering Strait).

Next, the first attached plot issued today by the BoM indicates that the 30-day moving average SOI has dropped down to -15.3; and you have to go back to 2006 to find a monthly SOI value this low.

The second plot issued by the BoM on May 4 2015, show the monthly SOI values from 2008 through ~ April 2015.
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #679 on: May 17, 2015, 04:12:18 PM »
As a follow-on to my brief post about the ENSO & Arctic Sea Ice:

The first attached image (posted by Neven in the Arctic Sea Ice folder) shows ocean heatflux volume pass through the Bering Strait; which indicates that I believe that by September the sea ice at this end of the Arctic Ocean will have an anomalously low extent.

The second attached image shows the typical anomalous surface distribution during a strong El Nino event from Dec to Feb; indicating that indeed, atmospheric telecommunication from the Tropical Pacific warms Southern Alaska; and the associated relatively warm air may, or may not, continuing moving into the Arctic region depending on the Artic Oscillation, AO.

The third attached image shows that during historically high AO periods large amounts of multi-year sea ice has been lost to the Arctic both by atmospheric warming and by advection of sea ice through the Fram Strait.  However, I note that historically the AO has not been unusually high during periods of strong El Ninos (which then circles back to my prior point that the atmospheric telecommunication of energy from the Tropical Pacific to Southern Alaska primarily effects the Arctic Sea Ice the following season by increasing the PDO and the subsequent advection of relatively warm North Pacific ocean water through the Bering Strait into the Arctic Ocean).
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #680 on: May 17, 2015, 04:59:55 PM »
The first attached image of NOAA's Eq Pacific Subsurface Temperature Anom for May 13 2015, shows that the current EKW is dissipating a substantial portion of its energy by spreading poleward off the coast of Latin America.

The second image of NOAA's Eq Pac Upper Ocean Heat Anom circa May 17 2015; shows that more heat is existing (via the EKW) the target region than is entering the target region (via the recent WWB), resulting in the continued decline in this index.

The third image shows that the GFS Ensemble MJO forecast from May 17 to 31 2015; which indicates that the MJO will remain relatively weak, so there should be no new WWBs near the dateline, as is confirmed by the fourth attached image of the U of Albany 5S-5N 850 hPa Wind Anom from May 17 to 24 2015.

Additionally, the SOI is still low as the Long Paddock Station Daily SOI for May 17 2015 was: -22.70
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

prokaryotes

  • Frazil ice
  • Posts: 284
    • View Profile
    • Climate State
  • Liked: 47
  • Likes Given: 37
Re: 2015 El Niño?
« Reply #681 on: May 17, 2015, 07:49:07 PM »
By the Blob, I guess that you mean the positive PDO

According to a Phys.org article

Quote
Though researchers disagree over just what this blob portends, the phenomenon is drawing intense scrutiny from climate scientists and oceanographers.
At the center of this debate is a poorly understood pattern of wind, ocean current and temperature variations that some scientists call the Pacific Decadal Oscillation, or PDO.
For decades at a time, researchers say, the Pacific Ocean can linger in either a warm or cold phase, switching between the two suddenly and unexpectedly. Each phase exerts unique and far-reaching effects on sea life and global climate, they argue, mirroring the warm and cool tropical cycles known as El Nino and La Nina, but over a longer period of time.

Read more at: http://phys.org/news/2015-04-wedge-seawater-blob-blamed-marine.html

Even though sea ice reached record levels in part of the Arctic in 1998, the next year (1999) broke previous ice extent records.

bigB

  • Frazil ice
  • Posts: 481
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2015 El Niño?
« Reply #682 on: May 17, 2015, 08:36:16 PM »
ASLR,

The monthly SOI graph you provided in reply #680 only shows what the 30 day avg SOI value was at the end of each month. Since yesterdays 30 day avg SOI value of -15.3 was not tied to any one month, I'm not sure I see how it correlates to the monthly SOI graph. The attached image shows the BOM graph of 30 day avg SOI values for 2008 through part of 2010. Note that the 30 day avg SOI dropped to about -24.0 during mid February 2010.

While on the subject of the SOI, the GFS model suggests that negative daily SOI values are likely to continue for the next few days. The 30 day avg may drop a bit more during this time but has likely just about bottomed out. The GFS model continues to suggest that very weak negative to even positive daily SOI values are to return by mid next week.   

EDIT: Also, upper ocean heat anomalies are likely to begin leveling off as subsurface warming associated with the latest WWB becomes more evident within the next week or so. We should have enough warm subsurface water to last into July. However, a solid feedback loop and more WWB activity are likely required by July if this El Nino event is to continue evolving along a path toward super status. I suspect that if this event begins to evolve in similar fashion to last year (brief periods of cooling followed by slightly longer periods of warming), we may never get beyond high end moderate, or low end strong El Nino levels (per NOAA's definition, that would be SSTA of roughly +1.3 to +1.6 deg c in Nino 3.4 region). That's just speculation though. It's still too early to know just yet but I suspect we'll have a better idea by the end of June.
« Last Edit: May 17, 2015, 10:32:32 PM by bigB »

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #683 on: May 17, 2015, 09:01:21 PM »
ASLR,

The monthly SOI graph you provided in reply #680 only shows what the 30 day avg SOI value was at the end of each month. Since yesterdays 30 day avg SOI value of -15.3 was not tied to any one month, I'm not sure I see how it correlates to the monthly SOI graph. The attached image shows the BOM graph of 30 day avg SOI values for 2008 through part of 2010. Note that the 30 day avg SOI dropped to about -24.0 during mid February 2010.

While on the subject of the SOI, the GFS model suggests that negative daily SOI values are likely to continue for the next few days. The 30 day avg may drop a bit more during this time but has likely just about bottomed out. The GFS model continues to suggest that very weak negative to even positive daily SOI values are to return by mid next week.   

All very good/valid points (indeed the two plots that I provide are not directly connected, but they were easy to post).
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #684 on: May 18, 2015, 03:30:36 AM »
Per the attached plot issued today by the BoM, the 30-day moving average SOI has dropped down to -16.8:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Michael Hauber

  • Nilas ice
  • Posts: 1115
    • View Profile
  • Liked: 168
  • Likes Given: 16
Re: 2015 El Niño?
« Reply #685 on: May 18, 2015, 10:34:06 AM »
Your opinion?

Will a 2015 Arctic sea ice melt season during an El Nino year shatter previous records?
http://climatestate.com/2015/05/15/will-a-2015-arctic-sea-ice-melt-season-during-an-el-nino-year-shatter-previous-records/

Previous el nino events have seen if anything below average ice melt in the first year of an el nino.  Consider in particular that 2006, 2009 and 1997 were all underwhelming as far as melt goes.  The second year has shown more evidence of enhanced melt:  1998: moderate record, 2007 big record, 2010, no record on extent, but a big volume record.

What is not clear is whether stronger melts in the second year are coincidence or related to the switch from el nino to la nina.  September minimum occurs in each case occurred well after the el nino had ended.  In 2003 el nino conditions did occur and there was no substantial drop in minimum, so perhaps the drop is related to the switch from el nino to la nina.  It could also be a delayed reaction to the el nino, after an el nino breaks up the heat concentrated in the tropics disperses into the higher lattitudes and may impact the poles towards the end of the process.  In this case we could see some influence from last year's almost el nino, but I doubt we'll see a substantial contribution to enhanced melt this year from the significant el nino now forming.

On the dramatic motion of warm water north along the west US coast following the extreme Kelvin waves last year, and that will be kept up by the extreme Kelvin wave just reaching the far east Pacific now.  This is not actually the motion of warm water along the coast, but the blocking of the cooler water trying to flow towards the equator along the coast, and the reduction of cooler water upwelling along the coast.  The current along the west US coast turns towards Japan before it gets to the Arctic, so the blocking effect won't go directly into the Arctic.  This current does split into a northward branch along the Alaska coast, and the southward branch towards the tropics.  Perhaps as the California branch is slowed down by the Kelvin wave the northern branch could speed up resulting in more warm water heading towards the Arctic.

Also the reduction in upwelling will cause warming along most of the coast, but the effect will reverse when Arctic regions are reached as the water is warmer below the surface in the Arctic (under the ice and very close to the ice edge only).

The Ridiculously Resilient Ridge (RRR) is a bit of a wildcard.  This feature is as far as I know not a standard el nino feature, but is certainly having a significant influence on the current El Nino situation and pushing it along.  The RRR is causing the current extreme situation in the Beaufort sea with melt, however so far the situation is restricted to a relatively small portion of the Arctic with much of the rest of the Core Arctic (i.e. Laptev to Beaufort + central) showing melt conditions much more in line with what has been average in recent years.  It will be interesting to watch and see if the extreme Beaufort situation expands with the help of albedo feedbacks to impact the whole basin, or if the weather conditions will switch yet again and slow things down again (or speed them up somewhere else).

Climate change:  Prepare for the worst, hope for the best, expect the middle.

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #686 on: May 18, 2015, 12:39:27 PM »
In order to gain some perspective I have decided that after today, I will take a break from posting until sometime after the 4th of July.

So with my final perspective on the current El Nino for a while:

The first and second images are from the Earth null school for May 18 2015, with the first showing the Earth Ocean Current & SSTA Map, indicating strengthening IPO/PDO conditions; and the second showing an Antarctic perspective on the Earth Surface Wind & MSLP Map, indicating a strengthening SPCZ resulting in dropping pressure over Tahiti & an ABSL directing wind & ocean current directly towards the ASE, West Antarctica.

The third image was issued by Cyclocane on May 18 2015 indicating: (a) increasing cloud cover, and a possible TD, near the International Dateline; and (b) a cloud pattern indicating a SPCZ has formed.

Finally, the SOI is still low as the Long Paddock Station Daily SOI for May 17 2015 was: -24.70
« Last Edit: May 18, 2015, 12:49:49 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

deep octopus

  • Grease ice
  • Posts: 559
    • View Profile
  • Liked: 6
  • Likes Given: 17
Re: 2015 El Niño?
« Reply #687 on: May 18, 2015, 03:30:03 PM »
Thanks for your great contributions ASLR. I hope your break serves you well so you can focus on your own life. I will likely be away when you return at that time, as I will be busy with family at the end of June and then out of the country during the first three weeks of July, but look forward to your (and everyone else's) postings when I return at that point.

As is common for me to do when I have a chance, here is the weekly SST update for each of the Niño regions as reported by NOAA . Indeed, there is not much to report on at all, other than that most of the regions cooled slightly, while the Niño 3.4 region held at 1.0 C.

                Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA
 08APR2015     26.7 0.9     27.9 0.5     28.4 0.7     29.6 1.2
 15APR2015     26.8 1.3     28.3 0.8     28.7 0.9     29.7 1.3
 22APR2015     26.7 1.5     28.4 1.0     28.7 1.0     29.9 1.3
 29APR2015     26.8 1.9     28.3 1.0     28.8 1.0     30.0 1.4
 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

According to the CDAS by NCEP/NCAR and as reported by Levi Cowan, the Niño 3.4 region was at 1.237 C as of yesterday morning, possibly the warmest read there in a long time.

Tor Bejnar

  • Young ice
  • Posts: 4606
    • View Profile
  • Liked: 879
  • Likes Given: 826
Re: 2015 El Niño?
« Reply #688 on: May 18, 2015, 03:34:30 PM »
Stay well, ASLR!
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

jai mitchell

  • Nilas ice
  • Posts: 2364
    • View Profile
  • Liked: 208
  • Likes Given: 60
Re: 2015 El Niño?
« Reply #689 on: May 18, 2015, 04:05:14 PM »
 8)

I think you will be back earlier as this will likely be a very significant melt season!
Haiku of Futures Passed
My "burning embers"
are not tri-color bar graphs
+3C today

Gray-Wolf

  • Grease ice
  • Posts: 948
    • View Profile
  • Liked: 131
  • Likes Given: 459
Re: 2015 El Niño?
« Reply #690 on: May 18, 2015, 07:00:04 PM »
I'd also like to wish you well on your break AbruptSLR!

Sometimes things just get too, too heavy to keep a head straight enough to enjoy the rest of life ( esp. family) when you are buried in both the terrible evolution we see occurring before us but also trying to limit the damage the climate deniers seem to so easily cause?

Keep well and as happy as life allows!
KOYAANISQATSI

ko.yaa.nis.katsi (from the Hopi language), n. 1. crazy life. 2. life in turmoil. 3. life disintegrating. 4. life out of balance. 5. a state of life that calls for another way of living.
 
VIRESCIT VULNERE VIRTUS

oren

  • First-year ice
  • Posts: 9817
    • View Profile
  • Liked: 3588
  • Likes Given: 3940
Re: 2015 El Niño?
« Reply #691 on: May 18, 2015, 10:42:36 PM »
ASLR, your rate of posting is simply amazing, especially as quantity in your case does not triumph over quality. Rest well, come back soon.

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2015 El Niño?
« Reply #692 on: May 19, 2015, 03:52:41 AM »
Thank you all for your kind words.
 
As one last post, I provide today's BoM plot of the 30-day moving average SOI; which has move up to -16.5:
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

bigB

  • Frazil ice
  • Posts: 481
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2015 El Niño?
« Reply #693 on: May 19, 2015, 03:55:22 AM »
ASLR,

Please take care of yourself. Thanks for having the patience to put up with me. You've taught me a lot over the past year and I really do look forward to seeing more from you in the future.

The GFS model still suggests that positive daily SOI values will take over later in the week (or maybe just very weak negative values). We'll have to watch SLP patterns closely during the next few days. For now, I suspect that the SOI has just about bottomed out (but it wouldn't surprise me if it dropped some during the next few days).

Also of note, per the latest CDAS data, the west-east SSTA gradient in the equatorial Pacific appears to be strengthening. If this continues, it would promote further weakening of the Walker circulation and the development of a positive feedback loop. As of the May 18th at 12z, the CDAS Nino indices were as follows:

Nino 1+2: +1.712 deg C
Nino 3: +1.189 deg C
Nino 3.4: +1.103 deg C
Nino 4: +0.838 deg C

EDIT: Had to make some changes to my post as ASLR is already back  :)

wili

  • Young ice
  • Posts: 3342
    • View Profile
  • Liked: 602
  • Likes Given: 409
Re: 2015 El Niño?
« Reply #694 on: May 19, 2015, 06:18:37 AM »
Best wishes, ASLR!
"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

CraigsIsland

  • Frazil ice
  • Posts: 206
    • View Profile
  • Liked: 4
  • Likes Given: 25
Re: 2015 El Niño?
« Reply #695 on: May 19, 2015, 07:02:09 AM »
Have a restful break and you've earned that many times over. Be well and we'll miss your amazing input here.

bigB

  • Frazil ice
  • Posts: 481
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2015 El Niño?
« Reply #696 on: May 20, 2015, 04:07:35 AM »
Per the attached plot issued by the BOM on May 19th, the 30 day avg SOI has dropped slightly to -17.1.

bigB

  • Frazil ice
  • Posts: 481
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2015 El Niño?
« Reply #697 on: May 20, 2015, 09:46:58 PM »
The first attached image from Carl Schreck's website shows the hovmoller plot of equatorial zonal wind anomalies for the last 30 days and the GFS forecast for the next 7 days, updated May 20th. Per the GFS model, moderate westerly wind anomalies are to develop in the Central equatorial Pacific. If this develops as advertised, it should result in some warming of SST in the Nino 3.4 region (which per CDAS data have cooled during the past few days). A more ideal location for these westerly wind anomalies would be on the eastern edge of the West Pacific (to assist with warm water downwelling and further eastward displacement of the West Pacific warm pool). However, the latest OSCAR data centered on May 17th (see second attachment), shows that the South Equatorial Current (SEC) is strengthening between 160W-140W (the opposite of what's beneficial to a strong El Nino). Westerly wind anomalies over the Central equatorial Pacific would likely help reverse or slow down that trend. Warm water associated with recent Kelvin wave activity needs to remain in the Eastern Pacific, keeping normal upwelling in that region suppressed, and the anomalous west to east SSTA gradient intact (which per CDAS data is also not as strong as few days ago). Another area worth keeping an eye on is the small portion of the SEC in the far Eastern equatorial Pacific that's flowing slightly stronger than normal from east to west. This is most likely associated with localized easterly wind anomalies that occurred during mid May and is not of too much concern at the moment (but is not the most encouraging sign if one is expecting a strong El Nino).

Also of note, the long run of strong negative daily SOI values appears to be coming to an end (as was expected). The Long Paddock daily SOI value came in at just -3.10. The GFS model suggests that positive daily SOI values will begin any day now and persist into early June (another not so encouraging sign). 

bigB

  • Frazil ice
  • Posts: 481
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2015 El Niño?
« Reply #698 on: May 20, 2015, 10:41:56 PM »
The following link leads to a lengthy but interesting YouTube video from the COP20 and discusses the significance of El Nino and its impacts:


bigB

  • Frazil ice
  • Posts: 481
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2015 El Niño?
« Reply #699 on: May 21, 2015, 05:03:15 AM »
Per the attached plot issued by the BOM on May 20th, the 30 day avg SOI has increased slightly to -16.9.