Many are aware that Joe Romm posted a rather over the top post discussing NOAA’s recent predictions of El Nino. Did any of you download the Monthly PDF?. Yes. NOAA does report the rather not-shocking news that that conditions are favorable to transition to El Nino. Some models, for example the NASA model, used to predict the Southern Oscillation predict strong El Ninos. Others predict a long period of “La Nada”. But few reading the NOAA would get the impression NOAA is firmly predicting the El Nino of the Baskervilles or some sort of impending doom.
The Southern Oscillation sort of works like this: El Nino, La Nada…. La Nina… La Nada… La Nada…. El Nino …. It goes back and fort sort of like sloshing in a bath tub. The timing is not perfectly regular; the strength of the El Ninos and La Ninas varies. The El Nino of 1998 was particularly fierce; the recent La Nina was medium-high. But, examining the graph to the right, even the feeble minded with no access to ENSO models would guess that since we’ve just experienced fairly long, noticeable, La Nina, El Nino is, as the baseball announcers would say “Due.”
The tone of Joe’s post also made it appear that the impending El Nino would somehow cause this decade to be the warmest on record.
Will this decade be the warmest on record? Almost certainly: This has nothing to do with El Nino. The first 8 years are warm relative to the 1990s. There are only 7 months to add to the average for Jan 2000-Dec 2009. Volcanic eruptions like Pinatubo can drive down temperatures (as they did in the 90s). However, the cooling effect is not immediate, and any eruption today would not affect temperatures for at least 6 months. Most of that cooling would affect the decade from 2010-2019.
It’s hardly surprising the 2000s will almost certainly be a record high. The earth’s surface temperature has been warming over the long trend and there were no major volcanic eruptions to cool things down. When 2010 rolls around, expect Joe Romm and others to report that the 2000’s was the warmest decade on record. Expect to me to compare to the projections and report whether it’s warmed as much as projected.
I think the magnitude of warming is something we should consider when making plans. But maybe that’s just me. . .
Data comparisons strongly indicate projections are overshooting observations. The t-tests I use include information about the weather noise due to ENSO when making the comparison. So, the conclusions aren’t overlooking the fact that we are in ENSO neutral conditions as opposed to the top of an El Nino. (The periods I mostly use for analysis happens to start in ENSO neutral conditions and currently ends there. But that’s not why I picked it. I picked it based on publication dates of IPCC documents.)
What does the result of statistical test showing IPCC projections are high compared to observations mean for the future? Who knows? But it’s a bit of information to consider when interpreting what IPCC projections mean for the future.
Now for the El Nino Watch!
As long as Joe made the impeding El Nino sound so ominous, why don’t we keep track of El Nino?
Did you know NOAA publishes weekly El Nino news every Monday? Here’s the June 8, PDF.
Here’s the “exciting” summary:
- ENSO-neutral conditions are present in the equatorial Pacific Ocean.
- Equatorial SSTs are warmer-than-average across much of the Pacific Ocean.
- Current observations and dynamical model forecasts indicate conditions are
favorable for a transition from ENSO-neutral conditions to El Niño conditions
during June-August 2009.
Here’s the forecast:
- A majority of ENSO models indicate above-average SSTs (greater than 0°C) in
the Niño-3.4 region through the remainder of 2009.- Most dynamical models predict El Niño (greater than +0.5°C) by Northern
Hemisphere summer, while all statistical models predict ENSO-neutral
conditions (-0.5°C to +0.5°C).
Translation: Current state, “La Nada” with ocean warmer than average over the Pacific. Might transition to El Nino soon. If you look at the graph, the NASA model is predicting a very strong El Nino; this would resemble 1998. CCD LIM is predicting “La Nada” continuing a long time. Other models are in between with the average predicting the earth’s climate will, indeed, end up in a fairly strong El Nino by the end of the year.
If the average model is right, I’ll have an extended tomato, basil and pepper harvest like in 2007. I planted sweet potatoes. They supposedly do better with a long growing season. So, maybe my first shot at sweet potatoes will have a super abundant yield.
Let’s not forget that Hansen’s NASA model was predicting a Super El Nino for 2006. We can all see how that one turned out.
Lucia: Let’s take a look at the RSS MSU TLT Time-Latitude Plot in light of your post. A recent version that I haven’t scribbled on is here:
http://i42.tinypic.com/2hfukjm.jpg
The eruptions of El Chichon and Mount Pinatubo are barely visible. Comparing the Time-Latitude plot to a Time-Series graph helps identify the timing and the TLT response.
http://i40.tinypic.com/2ljrh39.jpg
Same thing holds true for most ENSO events. You have to compare the Time-Latitude plot to a NINO3.4 SST anomaly graph to pick them out. The exception is the 1997/98 El Nino. It stands out above everything else:
http://i40.tinypic.com/6rj1p4.jpg
Tropical TLT skyrocketed in the months after the 1997/98 El Nino, then remained elevated after the 1998/99/00 La Nina. This was during a period when a series of moderate El Nino events (2002/03, 2004/05, 2006/07) occurred without a single “official†La Nina to counter them.
http://i43.tinypic.com/w8w7ig.jpg
But look at the Mid-to-High Latitude Northern Hemisphere TLT after the 1997/98 El Nino. A tremendous amount of heat from the 1997/98 El Nino was transported northward and remained there during the La Nina of 1998/99/00. It didn’t magically dissipate overnight. The northward transport of heat from the subsequent El Nino events in 2002/03, 2004/05, and 2006/07 helped maintain the elevated Mid-to-High Latitude TLT until the 2007/08 La Nina finally cooled things down a bit.
http://i42.tinypic.com/2d2ccy8.jpg
Evidently, then, the elevated Global TLT anomalies of the 2000s were primarily lingering effects of the 1997/98 El Nino that were maintained by the smaller El Nino events of the mid-to-late 2000s.
http://i43.tinypic.com/am8gnl.jpg
And as you said, the absence of a significant volcanic eruption also made the 2000s higher in temperature than the 1980s and 90s.
The graphs are from my post “RSS Time-Latitude Plots… …Show Climate Responses That Cannot Be Easily Illustrated With Time-Series Graphs Alone†here:
http://bobtisdale.blogspot.com/2009/06/rss-msu-tlt-time-latitude-plots.html
Regards
The NASA model in the ENSO forecasts is one used for Seasonal-to-Interannual prediction at GMAO in Maryland. It is completely independent of GISS and Jim Hansen.
http://gmao.gsfc.nasa.gov/
re-“warmest decade on record” Forgive me if I’m wrong, but is not the definition of “decade” ten years rather than time periods beginning and ending with years ending in zeroes? Was not the decade 99-08 cooler than 98-07? Defining decade the other way strikes me as disingenuous.
Gavin–
Thanks. But I think some of the confusion stems from GISS posts like this: http://data.giss.nasa.gov/gistemp/2005/ where the text says:
This is not based on the same NASA model illustrated in the NOAA figure, but it may well be the “Hansen” prediction Fred recalls. It’s a GISS page, but refers to no particular model. Reading the GISS text, the prediction method seems to be more in line with the casual one I describe in my post, i.e. ‘since we’ve just experienced fairly long, noticable, La Nina, El Nino is, as the baseball announcers would say “Due.‒
It may be unfair of Fred to associate this GISS text with Hansen. I don’t subscribe to his newsletter, so I don’t know whether Hansen himself made any sort of prediction.
Andrew_FL–
I think decade gets defined both ways in the venacular. We do tend to focus on the 30s, the 20s, the 50s etc.
When 2009 ends, we’ll all argue about this.
Regardless of any connection or lack there-of between NASA GISS/Hansen and the NASA GMAO model, the NASA GMAO is usually the outlier in terms of predicting an El Nino as it was in April of ’06: http://iri.columbia.edu/climate/ENSO/currentinfo/archive/200604/SST_table.html
Indeed it does appear to get used that way
http://en.wikipedia.org/wiki/Decade
It seems that the clear technical definition is the broad one, but the narrow definition is the commonly used one. Looks like we’re in for a bout of “accurate but not true” again…
PS. A simple Google search of “Hansen Super El Nino 2006” will show where he made that prediction.
Fred–
James Annan seems to have given a detailed account:
http://julesandjames.blogspot.com/2009/02/hansens-el-nino-forecast-reprised.html James writes:
The prediction was retracted when Hansen got flak from reviewers, but the draft was circulated.
The ENSO only changes global temperatures by about 0.07 *(Nino 3.4 anomaly) with a lag in that effect of 3 months.
The Super El Ninos can reach +3.0C anomaly in the Nino 3.4 region so the global temperature is only affected by +0.2C (3 months later) through the biggest El Ninos and less than that for moderate events.
This effect seems to be continuous in that there is always a 3 month lag in global temperatures from the ENSO, whether it is positive, negative and neutral.
It does look like we will have a small El Nino event but it is not going to cause any records to be broken. We would need a major spike in the AMO and southern ocean temperatures for that to happen.
Lucia, do you have any idea how models are shaping up with regard to sea ice? I seem to recall someone saying that the under predicting ice loss, and now Roger Pielke Sr. has pointed out an old paper from about ten years ago which claimed the models were on track:
http://climatesci.org/2009/06/09/an-comment-on-a-1999-paper-global-warming-and-northern-hemisphere-sea-ice-extent-by-vinnikov-et-al/
I imagine that they are probably slightly over predicting ice loss at the moment but overall doing well in this regard (although whether this is for the right reasons is a different story).
Andrew_FL–
The IPCC did not make as firm projections about sea ice as for the surface temperatures. So, to answer your question, someone has to decide which models are “the models”. After than, someone would have to download all the “model data” about sea ice and compute the loss over a period of time.
So, no I don’t know. I’m think the modelers say they underpredict the loss of sea ice. But I tend to not count evaluations like that unless I can first find a formal prediction published somewhere by someone, and then compare to that. Then I can say if that prediction was on target.
Lucia, you write: “The tone of Joe’s post also made it appear that the impending El Nino would somehow cause this decade to be the warmest on record. Will this decade be the warmest on record? Almost certainly: This has nothing to do with El Nino.”
It is no coincidence that the warmest decade of the century followed the “El Nino of the Century.” The 1997/8 El Nino (along with the 1986/7 El Nino) was radiative. It spurred a step-change in sea surface temperature across much of the Pacific and Indian Oceans. It slowed the Atlantic Meridional Overturning Circulation, which in turn drove the AMO permanently upward. I make this argument in my latest post, here: http://climatechange1.wordpress.com/2009/05/22/ten-questions-for-alarmists-about-the-el-ninosouthern-oscillation/
Regards,
Carl
Here’s a naïve how does an El Nino increase global temperature? I can understand how it might move heat around and so effect temperature measurements (especially if it moves warmth from an area with few sensors to one with a lot of senors) but if the total global energy balance (how ever defined and measured and modelled) hasn’t gone up or gone down doesn’t ENSO just redistribute? A simple explanation would be nice or a pointer to a clear detailed explanation would be ok 🙂 thanks
Andrew, your question is not naive at all, because the case for a radiative ENSO is rarely made. It is assumed by pretty much everyone that ENSO is not a radiative oscillation. Roy Spencer is getting close by modeling global temperature with a radiative PDO, but he misses the fact that the PDO is merely the cumulative effect of ENSO. In fact, ENSO involves variable cloud cover in the Pacific and Indian Oceans (making it radiative) and variable upwelling in the North Atlantic. The nature of the rise in SST, upper ocean heat content, and sea level support my argument. Once again, these arguments are made succinctly with the supporting graphics in my article, here:
http://climatechange1.wordpress.com/2009/05/22/ten-questions-for-alarmists-about-the-el-ninosouthern-oscillation/
I would appreciate any comments that you have.
Carl
Andrew Kennett: You asked, “Here’s a naïve how does an El Nino increase global temperature?”
My simplest explanation might be a little wordy, but bear with me.
During non-El Nino years (La Nina and ENSO-neutral years), heat accumulates in the Pacific Warm Pool. Some of that heat is from warm water that returns to the PWP from the El Nino events (the equatorial counter current relaxes after an El Nino and the equatorial currents move the warm water back from the eastern to the western equatorial Pacific). Some of it is the normal heat buildup caused by the trade winds pushing warm surface waters from east to west in the tropical Pacific. And some of the buildup of heat occurs during the preceding El Nino event itself, when cloud amounts over the PWP drop significantly, causing a major rise in downwelling shortwave radiation (visible light). During the 1997/98 El Nino, downwelling shortwave radiation rose as much as 25 watt/meter^2 over the PWP.
The Pacific Warm Pool covers an area that varies in size. I did a few comparisons a while back and could go find them if necessary, but my memory says it varies from (approximately) the size of the United States to the size of Russia. So it can be quite large. And it can also reach depths of 300 meters. To put it into technical terms, it’s a chunk of warm water. During significant El Nino events like the 1986/87/88 and 1997/98 El Ninos, the Pacific Warm Pool will pretty much “empty†its contents as the warm water sloshes east.
So the warm water that was in the Pacific Warm Pool, most of it below the surface, shifts east during the El Nino. The warm water rises to the surface during the process. The increase in surface temperature of the central to the eastern tropical Pacific causes the lower troposphere above it to rise, and atmospheric processes redistribute the heat around the globe. This is as far as most people carry the discussion.
Here’s the rest. Some BUT NOT ALL of the warm water returns to the Pacific Warm Pool during the subsequent La Nina. BUT (big but) the warm water that doesn’t return to the Pacific Warm Pool is now on the surface of the North and South Pacific and the Indian Ocean.
In other words, warm water that was below the surface of the Pacific Warm Pool (and not included in the calculation of global temperature) is redistributed around the SURFACE of the nearby oceans by the El Nino, (and it is now included in the calculation of global temperature). This can be seen as upward step changes in the sea surface temperatures of the East Indian and West Pacific Ocean after the 1986/87/88 and 1997/98 El Nino events. Refer to my posts here:
http://bobtisdale.blogspot.com/2009/01/can-el-nino-events-explain-all-of.html
http://bobtisdale.blogspot.com/2009/01/can-el-nino-events-explain-all-of_11.html
I hope that helped.
What amazes me is the incredibly large spread between the models of almost 2.5C! The good news is that these are short term projections so it doesn’t take more than a few months to figure out which one is right.
My guess is that if we do move to actual El Nino conditions it will be brief and barely meet the requirements to become official.
Bob,
GREAT description! The SSH map in my post demonstrates that all the heat ends up where the South & North equatorial currents that return PWP heat hit land (at Eastern coast of the Philippines and New Guinea).
Do you think that the MJO and the associated movement of cirrus cloud between the PWP and the Cold Tongue (amplified intensity there) could provide a locally enhanced greenhouse effect over the Cold Tongue? I don’t have an answer, but ENSO’s correlation with Pacific OLR is noteworthy. Also, Erl Happ has contended that ENSO’s heat comes from a long chain of events that end in a fall in cirrus cloud in the latitude bands 15 to 40, above and below the equator. Any thoughts?
Regards,
Carl
Carl: Your questions are outside of my areas of study.
My two bits worth on the cause and the prognosis for tropical and global temperature is to be found in an article titled El Nino. How big? How long? at http://climatechange1.wordpress.com that I put up last night.
Briefly, it is a change in ice cloud cover in the troposphere that modulates the amount of solar energy that gets into the ocean. That change is due to the ozone dynamic in the stratosphere that is ultimately under the control of the sun. This produces the strongest observable change in the temperature and rainfall in the latitude bands around 30°south latitude which is where I happen to live. These changes can occur abruptly as in 1976-83 or gradually over very long periods of time.
So, the litmus test for ENSO if you want to see where it all begins at the level of the Earths surface (the major effects) rather than the atmosphere (where the causes lie) is in South Africa, across Southern Australia and in the ocean and the mountains of South America.
ENSO 1,2 3,4, 3.4 and the the Pacific Warm Pool, the tropical Indian Ocean and the Atlantic are where you can observe the effects on tropical temperature of these changes that begin and have the greatest magnitude at about 30° south latitude.
Practically speaking, if you look at the temperature dynamic at 20hPa over the equator you can predict the course of ENSO with, if the past is to be our guide, a high degree of accuracy. That dynamic has the quality of a sine curve with peaks occurring at an average frequency of 27.1 months.
Understandably farmers in Australia have a strong interest in knowing what is about to happen with the weather. Much confusion and fear has been generated during the current climate scare. Understanding ENSO and it’s causes has more importance here than any other place on Earth, except perhaps the high latitudes where growing seasons will shrink as the tropics cool. In high latitudes of the northern hemisphere winters will continue to cool as the supply of warmth from the tropics is gradually strangled.
I think you can see how the ENSO affects atmospheric temperatures with this chart. ENSO versus Tropics temps.
http://img514.imageshack.us/img514/5729/ensotropics.png
The increased/decreased temps in the tropics then propogate out to the rest of the world fairly quickly – less than 1 month.
http://img23.imageshack.us/img23/1857/rsstropicsglobalqq9.png
Thank you for all your explainations. Am I right in understanding that while ENSO has no effect on global energy balance but that by driving an upwelling and spreading out of warm water in the Pacific tropics there is a resulting spreading out of warmer air and hence an observed rise in average global temperature?
Hi Andrew. Does ENSO affect the global energy balance? I would urge you to have a look at figure 4 and the related text in this post http://climatechange1.wordpress.com/2009/05/12/climate-change-a-la-naturale/
An El Nino event represents a period of rapid energy accumulation in the tropical ocean. In the most vigorous events the outgoing radiation from the Earth, as measured from space, actually falls while sea surface temperature rises.
La Nina events on the other hand are periods where energy acquisition is curtailed by increased cloud cover. Naturally, in this circumstance the atmosphere vents energy via the release of latent heat. La Nina is a period of strong cloud formation and precipitation. So, the specific humidity of the air actually falls during La Nina. So, the energy stored in ocean and atmosphere is vented away. Outgoing long wave radiation is seen to increase.
If one focuses on the global tropics (say 20°N to 20°S) rather than specific parts of the tropical ocean (like ENSO 3.4) these sorts of global parameters can be compared and we can talk of the global energy budget. We do not need to get bogged down by consideration of which parts of the tropical ocean warm the most, where the heat accumulates, whether any of it empties into other regions via ocean currents and so on.
Ultimately, what we want to know is how much this sort of ‘natural climate change’ contributes to the change in global temperature over time, where the heating occurs, in which season and so on.
Joe Romm is always over the top. He has called for Lutz to be fired at GM. Now he has a guest blogger, who said that by 2050 he’ll be 77 and will probably retire under water or on fire.
MikeN,
Here’s the bio for the guest blogger at Joe’s:
Is he planning to stay in Chicago? Because I doubt Chicago will be underwater in 2050 and I don’t thinks even a 4C increase in temperature would exactly set Chicago “on fire”.
That said, we did have an awfully big fire some time back. Brick & steel are now favorite construction materials in Chicago.