Waiting for El Nino

April 16, 2014

nino14

Australian Bureau of Meteorology: All international climate models surveyed by the Bureau indicate that SSTs in the equatorial Pacific Ocean will continue to warm during autumn and winter. Almost all models indicate El Niño thresholds will be exceeded during the southern hemisphere winter.

The well known climate denial canard – “There has been no warming in x years”, derives from the gigantic el nino event of 1998.  In El Nino events, warm water from the western Pacific spreads across to the eastern Pacific and the coast of South America. The ocean surface pumps enormous amounts of heat and moisture into the atmosphere, with effects on global weather and temperatures.  Historically these are warm years.
In the past decade, El Nino’s evil twin, La Nina, has been the more dominant influence – with cooler pacific waters that tend to suck more heat down into deeper levels, and are a damper on global temperatures.

The graph below shows the relationship between El Nino, La Nina, and global temperature.  Note that even the “cold” La Nina years continue to warm.

If a new El Nino develops, climate experts look for a new record in Global temperature, as well as a host of other extreme events around the planet.

World Meteorological Organization:

Since the second quarter of 2012, El Niño-Southern Oscillation (ENSO) indicators (e.g., tropical Pacific sea surface temperatures, sea level pressure, cloudiness and trade winds) have generally remained at neutral levels. This is expected to continue into the earlier part of the second quarter of 2014, according to the WMO Update.

However, since February there have been two strong westerly wind events, and a general weakening of the trade winds in the tropical Pacific. This has led to a significant warming of the waters below the surface of the central Pacific, which historically has been one of the precursors to El Niño development. While there is no guarantee this situation will lead to an El Niño event, the longer the trade winds remain weakened, and subsurface temperatures stay significantly warmer than average, the higher the likelihood of the emergence of an El Niño.

 “Model forecasts indicate a fairly large potential for an El Niño, most likely by the end of the second quarter of 2014,” said the Update, which is compiled from inputs from climate experts and prediction models around the world. “For the June to August period, approximately two-thirds of the models surveyed predict that El Niño thresholds will be reached, while the remaining models predict a continuation of neutral conditions. A few models predict an earlier El Niño onset, such as in May. No model suggests a La Niña in 2014.”

However, the strength of the possible El Niño cannot be reliably estimated at the current time.

“El Niño and La Niña are major drivers of the natural variability of our climate. If an El Niño event develops – and it is still too early to be certain – it will influence temperatures and precipitation and contribute to droughts or heavy rainfall in different regions of the world,” said WMO Secretary-General Michel Jarraud. “The major advances in our forecasting capabilities mean that we will be better prepared to manage the impact of these events especially if extreme on agriculture, water, health and many other climate-sensitive socio-economic sectors.”

 “El Niño has an important warming effect on global average temperatures, as we saw during the strong El Niño in 1998” said Mr Jarraud. “Only two out of the past 15 years were categorized as El Niño years, and yet all were warmer than average. “The combination of natural warming from any El Niño event and human-induced warming from greenhouse gases has the potential to cause dramatic rise in global mean temperature,” he said.

It is important to stress that no two El Niño events are the same, and that other drivers also influence climate patterns.  At the regional level, seasonal outlooks are needed to assess the relative impacts of both the ElNiño/La Niña state and other locally relevant climate drivers. For example, the state of the Indian Ocean Dipole, or the Tropical Atlantic SST Dipole, may impact the climate in adjacent land areas.

Australian Bureau of Meteorology:

The following graph shows the average forecast value of NINO3.4 for each international model surveyed for the selected calendar month. If the bars on the graph are approaching or exceeding the blue dashed line, there is an increased risk of La Niña. Similarly, if the bars on the graph are approaching or exceeding the red dashed line, there is an increased chance of El Niño.

 

Below, the “1998” myth discussed in a classic Climate Crock of the Week video:

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6 Responses to “Waiting for El Nino”


  1. “The well known climate denial canard – “There has been no warming in x years”, derives from the gigantic El Nino event of 1998.”

    Yes, but after the “El Nino event of 1998”, was very strong and deep, La Nina. The trend in global temperatures for the period after these two phenomena (from circa 2001-2) it’s – continue “the flat”.

    “Historically these are warm years.”

    Consent. A problem, however, is not in This but in this:

    Professor H. von Storch (http://www.spiegel.de/international/world/interview-hans-von-storch-on-problems-with-climate-change-models-a-906721.html) :
    “In other words, over 98 percent of forecasts show CO 2 emissions as high as we have had in recent years leading to more of a temperature increase.”
    “This wouldn’t mean that there is no man-made greenhouse effect, but simply that our effect on climate events is not as great as we have believed. […]”

    But for “gigantic El Nino” is likely to need a gigantic volcanic eruption (http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00471.1).

    • dumboldguy Says:

      More incoherence from the second most incoherent visitor to Crock (after Omnowhoisalwaysconfused, of course).

      And “gigantic volcanic eruptions”? Lord love a duck!

      Arkady, why don’t you and Omno do a “Joe Versus the Volcano” for us and jump into the next one that erupts?

      • dumboldguy Says:

        PS Got distracted by the volcano foolishness. Wanted to say that
        this is an excellent El Nino update, and that the “1998 Myth” video was excellent—-I’m sure it flushed a large number of denier toilets.


    • semczyszakarkadiusz wrote:

      … after the “El Nino event of 1998”, was very strong and deep, La Nina. The trend in global temperatures for the period after these two phenomena (from circa 2001-2) it’s – continue “the flat”.

      Perhaps the “flatness” that you speak of is due to your choice of temperature index or its lack of coverage in the Arctic? It is difficult to know since you don’t actually name the index. Perhaps it is one of your own devising?

      If you use HadCrut4v (which of the major indices has tended to show the least warming, in part, since it simply omits the Arctic rather than attempt any sort of interpolation) the rate of warming for January 1997–December 2012 is 0.046 ± 0.063 C/decade. Not statistically significant warming at the 95% level, but warming nevertheless. If you use a kriging method based off of satellite data to interpolate temperatures over the Arctic, the trend becomes 0.108 ± 0.073, which is statistically significant even at the 95% level.

      Please see:

      Cowtan, Kevin, and Robert G. Way. “Coverage bias in the HadCRUT4 temperature series and its impact on recent temperature trends.” Quarterly Journal of the Royal Meteorological Society (2013).
      Open Access: http://onlinelibrary.wiley.com/doi/10.1002/qj.2297/full

      This is, however, somewhat lower than warming over the previous two decades. Internal variability (principally in terms of the el Nino Southern Oscillation, solar variability and reflective aerosols due to volcanic activity) adds noise to the warming signal, and can either make the underlying trend appear less than or greater than it actually is. Fortunately it is possible to remove the noise.

      A 2011 paper looked at each of five major global temperature indicies, three surface (GISS, NCDC and CRU) and satellite (RSS and UAH) and three sources of natural variability that introduce noise into the temperature signal: the El Nino Southern Oscillation (in the form of the Multivariate el Nino Index MEI), solar variability (by means of total solar irradiance) and reflective aerosols due to volcanic activity. Once these sources of natural variability were accounted for the trend line appears quite stable.

      The authors state:

      Figure 4 shows the adjusted data sets (with the influence of MEI, AOD and TSI, as well as the residual annual cycle removed) for monthly data. Two facts are evident. First, the agreement between the different data sets, even between surface and LT data, is excellent. Second, the global warming signal (which is still present in the adjusted data because the linear time trend is not removed) is far clearer and more consistent. When the fluctuations in temperature over the last 32 years (which tend to obscure the continuation of the global warming trend) are accounted for, it becomes obvious that there has not been any cessation, or even any slowing, of global warming over the last decade (or at any time during this time span). In other words, any deviations from an unchanging linear warming trend are explained by the influence of ENSO, volcanoes and solar variability.

      Foster, Grant, and Stefan Rahmstorf. “Global temperature evolution 1979–2010.” Environmental Research Letters 6.4 (2011): 044022.
      Open Access: http://iopscience.iop.org/1748-9326/6/4/044022/fulltext/

      semczyszakarkadiusz quotes Storch:

      … over 98 percent of forecasts show CO 2 emissions as high as we have had in recent years leading to more of a temperature increase.

      That seems rather doubtful as there will be a great deal of variation between different runs of the same model, variation that essentially models natural variability, albeit simply as noise. I suspect that what he is comparing are means of the individual runs for each model, not the individual runs themselves, the latter of which has a much wider spread over the short-term. It is hard to tell what exactly he was going off of based simply on the context given by the Der Spiegel interview. Other issues are possible.

      Please see:

      IPCC model global warming projections have done much better than you think
      Dana Nuccitelli, 2013-10-01
      http://www.skepticalscience.com/ipcc-model-gw-projections-done-better-than-you-think.html

      However, rather than simply looking at the forecasts of the models, once history has played out and we know how El Niño, the sun and volcanoes behaved, we can use the behavior of the sources of natural variability as input for the models, then calculate how the climate system should evolve given this input. This is called a hindcast.

      When we perform hindcasts, we find:

      Climate Models Show Remarkable Agreement with Recent Surface Warming
      Rob Painting, 28 Mar 2014
      http://www.skepticalscience.com/Climate-Models-Show-Remarkable-Agreement-with-Recent-Surface-Warming.html

      semczyszakarkadiusz wrote:

      But for “gigantic El Nino” is likely to need a gigantic volcanic eruption

      I don’t think the paper you cite means what you think it means. Perhaps you could cite the relevant passage? Or at least link to something open access?

      Regardless, the reason why some expect this upcoming el Nino to be a big one is due to the size and temperature of the pool of water that is coming to the surface.

      Please see:

      The warm water just below the ocean’s surface is on par with that of the biggest El Niño ever recorded, in 1997-98. That event caused $35 billion in damages and was blamed for around 23,000 deaths worldwide, according to the University of New South Wales. The 1997-98 El Niño is also the only other time since records begin in 1980 that sub-surface Pacific Ocean water has been this warm in April.

      El Niño Could Grow Into a Monster, New Data Show
      Eric Holthaus. 2014-04-07
      http://www.slate.com/blogs/future_tense/2014/04/07/el_nino_2014_2015_forecasts_show_it_could_grow_into_a_monster.html

      … but it is difficult to say. A big one could affect a lot of people. But in terms of global warming, a big El Nino is simply so much noise added to the signal, temporary, ephemeral.

  2. rayduray Says:

    See: http://www.bom.gov.au/climate/enso/#tabs=Sea-sub%E2%80%93surface

    Weekly subsurface temperatures in the equatorial Pacific. The animation shows the very recent development of a second mass of anomalously warm water at 50 meters and centered at about 115 degrees W.

  3. redskylite Says:

    Thanks for a very informative and clear El Nino update and video, and talking of the Heartland Institute this caught my eye this morning:-

    http://skepticalscience.com/Heartland_Logic.html


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