Climate models

El Nino Report: Models still predicts “moderate” to “strong”

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El Niño is still present, but it hasn’t yet turned into the “El Niño of the Baskervilles” one might have worried about based on Joe Romm’s rather excited prose earlier this summer. This is the introduction from NOAA’s latest monthly update with some bits highlighted:

A weak El Niño continued during August 2009, as sea surface temperature (SST) remained above-average across the equatorial Pacific Ocean (Fig. 1). Consistent with this warmth, the latest weekly values of the Niño-region SST indices were between +0.7°C to +1.0°C (Fig. 2). Subsurface oceanic heat content (average temperatures in the upper 300m of the ocean, Fig. 3) anomalies continued to reflect a deep layer of anomalous warmth between the ocean surface and the thermocline, particularly in the central Pacific (Fig. 4). Enhanced convection over the western and central Pacific abated during the month, but the pattern of suppressed convection strengthened over Indonesia. Low-level westerly wind anomalies continued to become better established over parts of the equatorial Pacific Ocean. These oceanic and atmospheric anomalies reflect an ongoing weak El Niño.

A majority of the model forecasts for the Niño-3.4 SST index (Fig. 5) suggest El Niño will reach at least moderate strength during the Northern Hemisphere fall (3-month Niño-3.4 SST index of +1.0°C or greater). Many model forecasts even suggest a strong El Niño (3-month Niño-3.4 SST index in excess of +1.5°C) during the fall and winter, but current observations and trends indicate that El Niño will most likely peak at moderate strength. ….

Below, I’ve reproduced the model forecasts. As stated in NOAA’s narrative, some models predict El Niño will strengthen significantly. In particular, COLA CCSSM3 is still predicting a ripping hot El Nino for NINO3.4 SST anomaly for DJF. On the other hand, CDC LIM predicts a sharp linear drop from the present value:
El Nino Forecasts

Given the spread, does anyone want to bet on the magnitude of Nino3.4 SST for Sept-Oct-Nov? I can set that up. (I’ll be opening bets for August UAH at the end of the week.)

41 thoughts on “El Nino Report: Models still predicts “moderate” to “strong””

  3. Lucia,

    Have you looked at how well the actual value each month comes in against predicted values 1, 2, and 3-month out? IOW, what’s the batting average of each model?

  8. Fred Nieuwenhuis (Comment#19700)-Wow, those models are pretty bad!

    Of course, they are predicting weather, so it’s not surprising that they fail.

    But they can predict the mean without knowing the individuals in the population. 😉

  9. Wagerers: Keep in mind that there is a secondary pool of warm water making its way across the equatorial Pacific in the upper anomaly animation of the following link. In the lower one, note how the thermocline appears to be flattening again. That’s an indication that the warm water is travelling to the east, which was pretty obvious in the upper animation.
    http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/wkxzteq.shtml

    The same pool of warm water appears in the JPL Sea Level Residuals:
    http://sealevel.jpl.nasa.gov/science/jason1-quick-look/2009/images/20090821G.jpg

    Also keep in mind that the second year with La Nina conditions (winter of 2008/09) added a chunk-o-heat to the tropical Pacific:
    http://i31.tinypic.com/2s96hd1.png

    Which is one of the “Raw” graphs from my OHC post:
    http://bobtisdale.blogspot.com/2009/09/enso-dominates-nodc-ocean-heat-content.html

    Now the questions: Is there anything else to strengthen the El Nino? Or will cooler waters from somewhere else cause it to dissipate?

  10. I know that you are also looking at relationship of El Nino to tropospheric temps. Your RSS monthly post is not out yet, so I’ll post this here.

    Here are the RSS values for summer 1997 (in advance of the 1998 El Nino).

    1997 6 0.018
    1997 7 0.166
    1997 8 0.202
    JJA 0.129

    Here are the values for this past summer.
    2009 6 0.081
    2009 7 0.392
    2009 8 0.270
    JJA 0.248

    Now here are temps resulting from El Nino in 1998.
    1997 12 0.303
    1998 1 0.550
    1998 2 0.736
    DJF 0.530

    1998 3 0.586
    1998 4 0.858
    1998 5 0.668
    MAM 0.704

    Tropospheric temperatures generally peak 6-7 months after the El Nino peak. So we shouldn’t expect the peak in temperature rise until next year (approximately a half year after the El Nino index peak).

    I suppose you could look at UAH too, but in this case the annual cycle does pose a possible confounding issue.

  11. Deep

    I suppose you could look at UAH too, but in this case the annual cycle does pose a possible confounding issue.

    Even though you are comparing August to August, July to July and June to June? 🙂

    More stuff happened this month, so I’m probably not running an RSS specific thread. But we did know they were down!

  12. I showed JJA 1997 against DJF and MAM 1998 for RSS. A moderate-to-strong El Nino will probably show rises in 2010 over JJA 2009, but less than in 1998 over JJA 1997.

    Such comparisons are compromised by a strong annual cycle, so for now I wouldn’t bother for UAH.

  13. Deep

    I showed JJA 1997 against DJF and MAM 1998 for RSS.

    In addition to june, july and august 1997 vs jun july and august 2009. Presumably, any annual cycle does not affect the jun-jun, july-july or august-august comparison.

    Yes…. we know that El Nino has recently arrived, predicted to deepened, and the tropospheric temperaures are likely to lag. If El Nino deepens we expect tropospheric temperature to rise. (And I may have tomatoes well into the fall, but the Australian farmers are hoping that I don’t have October tomatoes because they want rain.)

    Obviously, we will all be monitoring both RSS and UAH. If you think your theory about the annual cycle gives you a special predictive abilities, why not enter the poll and win some quatloos?

  14. Doesn’t the emergence of El Nino to drive warming global temps sort of make the AGW claims look foolish?
    And one more question, please:
    If the Pacific waters involved heat up, doesn’t that mean in terms of energy flow, the heat is leaving the global system?

  15. hunter

    Doesn’t the emergence of El Nino to drive warming global temps sort of make the AGW claims look foolish?

    No. El Nino exists regardless of global warming. So, we will see these fluctuations. Right now, El Nino is present, so we expect global temperature to rise because of that in the short term. But, we also expect underlying warming to add to that in the long run.

  18. So the AGW extremist points is that when the El Nino, a known natural warming engine kicks on, things warm up.
    But what is the net result of an El Nino? Does it leave more, or less, heat in the system?

  20. hunter

    Does it leave more, or less, heat in the system?

    I don’t know. I don’t know whether El Nino is correlated with warmth due to some effect on clouds letting more energy in of if it’s mostly due to anomalously war ocean water sitting at the surface and so not cooling.

    I think Bob Tisdale discusses this a lot, but I don’t know myself.

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  22. It results in more water vapor in the atmosphere, a larger area of sea surface with warmer temperatures, and moves warmer weather patterns to higher lattitudes… all with an overall positive effect on global temps

  24. Let’s compare the Nino region anomalies for the same time of year between this El Nino and the 1997-98 Super El Nino.

    Week Nino1+2 Nino3 Nino34 Nino4

    10SEP1997 4.0 3.0 2.3 0.8
    09SEP2009 0.5 0.8 0.9 0.8

    They are not really close. This El Nino is only about 1/4 the strength of the 1997-98 one at the same time of year. There is a definitive seasonal signal to the ENSO with about 80% of El Ninos/La Ninas peaking in the November to January period.

    A regression of the Nino 3.4 region on global temperatures results in = 0.07 * Nino 3.4 anomaly of 3 months previous.

    So, global early-December temperatures will only be about 0.056C higher than they would have been with neutral Nino conditions. ie, hard to measure and very hard to notice.

    The Tropics regression is about = 0.2 * Nino 3.4 anomaly of 2.5 months previous.

    So, the Tropics will have slightly higher late-November temperatures but it will also be very hard for anyone to notice.

  25. Hunter, in the long run there will be none. But in the short run, it depends on how you measure to confirm your energy budget numbers. El Nino has a lot to do with ocean water in the top 300 meters which gets moved both verticaly and horizontaly depending on the trades. I’m not sure how energy budget calculations deal with that, but the cycles come in annual, decadal and century scale timeframes without a good knowledge of the cycles or their causes.

  26. Hunter, in the long run there will be none. But in the short run, it depends on how you measure to confirm your energy budget numbers. El Nino has a lot to do with ocean water in the top 300 meters which gets moved both verticaly and horizontaly depending on the trades. I’m not sure how energy budget calculations deal with that, but the cycles come in annual, decadal and century scale timeframes without a good knowledge of the cycles or their causes.

  27. Could it be that since the temperature goes up, the net effect is that heat content goes down? The temperature is not going up because energy inputs are going up significantly, is it? The energy represented by the temperature increase is not going into a giant flux capacitor someplace. Is it not going into either evaporation, which takes a lot of energy, or air, which does not hold heat very well, or radiation, which is leaving the system. Feel free to laugh or make merry for any significant item I have over looked.

  28. Hunter, actually, the ocean can work something like a capacitor… and it can also work something like a conductor… during La Nina, cooler water is drawn to the surface and across the equator by the trades and sort of condensed into a small area out by Indonesia. During El Nino, the trades do not blow hard enough to draw that water up and the warm area is spread across the Equatorial Pacific, sort of becomes stagnant in a heat sense

  29. Hunter: You asked about an El Nino, “And what is the net effect on the energy budget?”

    KNMI recently added a the Levitus et al (2009), identified as NODC, OHC data to their Climate Explorer. I broke the data down into smaller datasets:
    http://bobtisdale.blogspot.com/2009/09/enso-dominates-nodc-ocean-heat-content.html
    Many of the OHC datasets outside of the tropical Pacific appear to have upward step changes at different lags in response to significant traditional El Nino events. At the same time, for those larger El Nino events, the tropical Pacific OHC drops during the El Nino, but is then recharged during the subsequent La Nina. If the La Nina lasts for two years, like after the 1972/73 and 1997/98 El Ninos, the second year of the La Nina will result in a net gain to the tropical Pacific OHC. Sound counterintuitive, but that’s what the data shows.

    And at the same time, those significant El Nino events are releasing heat into the troposphere, causing step changes there as well:
    http://bobtisdale.blogspot.com/2009/06/rss-msu-tlt-time-latitude-plots.html
    So there are increases in OHC and increases in TLT as part of those significant traditional ENSO (El Nino/La Nina) events.

    Then you have to throw in the effects of the AMO on both datasets.

  30. Bob and Mike C,
    Thank you for clarifying that some.
    One question that sticks in my mind is that if the increased forcing is as small as the consensus claims, then the I wonder if the net effect of El Nino / La Nina cycles are to move heat out of the system, I guess mostly to space? The linger rate of heat in the atmosphere must be very short, since the heat content of air is so tiny. IOW, if the ‘heat charge’ builds up, and is released via El Nino, the energy moves out into the atmosphere and is gone. Sort of like a battery powered hand warmer, the heat is going to dissipate fairly quickly once the battery runs down. I guess the AGW community is going to say in this case the ‘battery’, the CO2 forced heating, keeps the battery recharged, and therefor increases will continue, increasing and more dramatic.
    But that does not seem to comport with reality at all.

  31. hunter: You wrote, “The linger rate of heat in the atmosphere must be very short, since the heat content of air is so tiny. IOW, if the ‘heat charge’ builds up, and is released via El Nino, the energy moves out into the atmosphere and is gone.”

    The heat released by significant El Nino events is transported poleward, primarily to the Northern Hemisphere. If we look at the TLT anomalies of the mid-to-high latitudes of the Northern Hemisphere after the 1997/98 El Nino…
    http://i42.tinypic.com/e9b04g.jpg
    …the elevated TLT anomalies linger through the La Nina of 1998/99/00, and longer, until the lesser subsequent El Nino of 2002/03 bumps it back up again.
    http://i44.tinypic.com/16leq39.jpg

    From this post:
    http://bobtisdale.blogspot.com/2009/06/rss-msu-tlt-time-latitude-plots.html

  32. Thanks Bob, for the graphs.

    Is there any concern that there has been a climate shift such that this major El Nino followed by smaller ones keeping the elevated TLT will become a sustained pattern? I.e. Major El Nino, 3 bumps, Major El Nino, repeat? Or is this an anomalyous pattern and we will return to a situation where these El Ninos are allowed to dissapate?

  33. JK: NINO3.4 SST anomaly data appears to follow the Southern Ocean SST anomalies. The thin grey line in the following graph that’s running along with the Southern Ocean data is the 6th-order polynomial trend of the NINO3.4 SST anomaly data:
    http://i44.tinypic.com/o7srh3.jpg
    I’ve used the poly trend line to highlight the fact that the underlying trend in the NINO3.4 SST anomaly data correlates with the Southern Ocean data.

    If the Southern Ocean feeds back to the tropical Pacific through the Humboldt Current, and if that feedback was causing the higher magnitudes of El Nino events over the past three decades, and if the Southern Ocean SST anomalies continue to drop, (lots of ifs), then I don’t foresee another bout of the significant El Nino events anytime soon.

    Time will tell.

  36. Crap. After the year the year we have just suffered through, I have been pulling for a “moderate to strong” El Nino big time.

  37. Hunter, Chang published a paper in 2007 on his observations of heat release during El Nino events and I recall he was pretty flabbergasted

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