Today Anthony Watts is sticking his neck out and predicting a La Niña later this year (archived here). What he's done is copied and pasted the first four paragraphs and a chart from a Reuters article by Karen Braun, changed the headline and, in defiance of copyright, provided no attribution, just an unlabeled link. That means that unless you notice the link, you might think that Anthony himself was the author (except his writing isn't as good). He's not the author. He has added no original words himself except for a slight word change in the headline. The original headline was:
COLUMN: How much clarity do we have on transition to La Niña? - BraunAnthony Watts' changed it to:
How Much Global Cooling Will We See On Transition To La Niña?Karen Braun in her article didn't totally commit to La Niña. Anthony, by leaving out most of her article and changing the headline did. Time will tell if his
Karen Braun, in the part that Anthony didn't copy and paste, wrote how a number of things need to happen before a La Niña arrives. She listed several indicators that are useful predictors of whether a La Niña will happen this year and if it does, whether it will be stronger or weaker. Karen Braun did think a La Niña looks likely, writing:
The short question-and-answer session would look like this: Are we headed for La Niña toward the end of 2016? Looks that way. Will it be a big one? Not sure.
Karen Braun is braver than some meteorologists. The Australian Bureau of Meteorology slightly favours a neutral period over a La Niña. It has this to say in its latest ENSO wrap-up (pdf here):
For winter and spring, climate models favour ENSO neutral slightly ahead of La Niña. However, accuracy of forecasts made at this time of year are lower than those at other times, and therefore some caution should be exercised.This is what their latest models look like as at 13 March. Only one of them strays into La Niña territory before the end of the year:
|Figure 1 | POAMA monthly mean NINO 3.4 sea surface temperature forecast from 13 March 2016. All eight international climate models surveyed by the Bureau indicate central Pacific sea surface temperatures (SSTs) will continue to cool in the coming months. Most models indicate a return to ENSO neutral during May to June, however there is a considerable spread in the model outlooks by the end of winter with some models edging towards, or exceeding, La Niña thresholds and others staying firmly in neutral territory. Source: BoM (pdf here)|
Other analysis from WUWT and Reuters
Anthony posted a chart from the Reuters article that showed what the author said were El Niño to La Niña years and analogues of this past year. I don't agree that they are all analogues. The chart would have been more correctly labeled if it just said it was from selected years. (As always, click the chart to enlarge it.)
|Figure 2 | Nino 3.4 sea surface temperatures for selected years. Source: Reuters article - chart here Credit: Karen Braun|
Apparent discrepancies in the above chart
I don't know where Karen Braun got her information from, but it doesn't line up with that from BoM. Below is a table with the years shown above and whether the following years were neutral or La Nina, according to the records at BoM:
Despite the label on the Reuters chart, three of the years shown in the chart in Figure 2 above were not followed by a La Niña, according to BoM, and one of them (2004-05) wasn't an El Niño year.
Moderate to strong El Niño years
So I've done my own research. The chart below is a plot of the Niño 3.4 sea surface temperatures for the very strong, strong, and strong to moderate El Niño years since 1950. The first chart shows all such years:
|Figure 3 | Nino 3.4 sea surface temperatures for strong to moderate El Nino years and subsequent year. Data source: NOAA|
That's got too many squiggly lines so I've separated the years into those that were followed by a La Niña. That was easy, because there are only three of them:
|Figure 4 | Nino 3.4 sea surface temperatures for strong to moderate El Nino years followed by a La Nina. Data source: NOAA|
This next chart shows the moderate to strong El Niño years that weren't followed by a La Niña, or not in the same year. Three years barely touched the threshold and one year (1981-82) didn't come close:
|Figure 5 | Nino 3.4 sea surface temperatures for strong to moderate El Nino years not immediately followed by a La Nina. Data source: NOAA|
Moderate to strong La Niña years
This next chart shows the strongest La Niña periods since 1950, being 1954-57, 1975-76 and 2010-12. In the most recent strong La Niña, 2010-12, the Niño 3.4 region didn't get as cold as it did in previous periods:
|Figure 6 | Nino 3.4 sea surface temperatures for strong La Nina years and subsequent year. Data source: NOAA|
For the sake of completeness, here are some charts showing moderate to strong La Niñas since 1950, starting prior so you can see which were preceded by an El Niño.
This first chart is another spaghetti plot showing all the moderate to strong La Niñas:
|Figure 7 | Nino 3.4 sea surface temperatures for strong to moderate La Nina periods and immediately prior period. Data source: NOAA|
Looks can be deceiving, so again I've separated the plots. This next chart shows moderate to strong La Niña's that were preceded by an El Niño, together with the current El Niño period. There were four moderate to strong La Nina periods that were preceded by an El Niño (of any strength). They are 1975-76, 1988-89, 1998-01 and 2010-12:
|Figure 8 | Nino 3.4 sea surface temperatures for strong to moderate La Nina periods that were preceded by an El Nino, with prior period. Data source: NOAA|
The chart below is of moderate to strong La Niña years that were not immediately preceded by an El Niño (of any strength). There are only three moderate to strong La Niñas that weren't preceded by an El Niño. They are 1954-57, 1964-65 and 1970-72.
|Figure 9 | Nino 3.4 sea surface temperatures for strong to moderate La Nina periods not immediately preceded by an El Nino, and prior period. Data source: NOAA|
Will there be a La Niña this year?
BoM says the chance is slightly against a La Niña developing, but urges caution. This time of the year is not the best time for making any predictions. Your guess is probably as good as mine or better, and I'm not guessing. So you're stuck with your own guess or you can choose from the guesses of Anthony Watts and Karen Braun, or the predictions or lack of predictions from the experts.
To help or hinder you, of the seven strongest El Niños since 1950, three were immediately followed by a La Niña and four were not. (See Figures 3, 4 and 5 above.)
Although I took issue with one of her charts (Figure 2 above), Karen Braun's article did contain some very good information that Anthony neglected to copy and paste. You can read the full article here.
As a bonus, and in case you missed it, below is the comparison of this year with the two previous hottest years having an El Niño. This is a plot of global mean surface temperature, whereas the charts above are just the Niño 3.4 sea surface temperatures.
|Figure 10 | Global mean surface temperature for El Nino years. Data source: GISS NASA|
From the WUWT comments
Not everyone is as confident as Anthony Watts that a La Nina is about to descend, though a few of the deniers are. A lot of them don't know much about ENSO events, despite or perhaps because of Bob Tisdale's articles.
Bill Illis has spotted a patch of blue and is convinced it means a La Nina is imminent:
March 21, 2016 at 9:53 am (excerpt)
The Pacific is definitely rapidly transitioning to a La Nina state.
All this blue colder than normal water in the undercurrent is going to surface soon and become the La Nina.
This Upper Ocean Temperature Anomaly chart shows that the average ocean temperature down to 300M from 180W to 100W has already transitioned into below average territory.That may be so or not. What it doesn't indicate is that a La Nina is necessarily going to happen this year. For one thing, it takes more than a drop in sea surface temperature, winds (and associated pressure gradients) matter too.
Traditionally, this value leads the Nino 3.4 index by about 1 month on a very consistent basis.
Ack is a nutty conspiracy theorist who ignores all the times that the scientists forgot to get rid of past La Nina's:
March 21, 2016 at 10:07 am
I predict no global cooling, as those who control the data will make some epic adjustments.
Talk of ENSO events seems to have brought out a lot of WUWT's pet conspiracy theorists for some inexplicable reason. Peter Miller wrote:
March 21, 2016 at 12:24 pm
Such is climate science today.
Adjusting/manipulating/homogenising/torturing data to meet the requirements of the Klimate Establishment is one of the great tragedies of our world today.
Bruce Cobb seems to think that scientists haven't heard of ENSO events and will instead attribute any short term downward wiggle in surface temperature as being "blamed" on "global warming/climate change". I don't know why he thinks that:
March 21, 2016 at 10:43 am
Any global cooling will be blamed on “global warming/climate change”. Like day follows night.
redc1c4 pokes fun at the WUWT ice age comethers.
March 21, 2016 at 2:52 pm
ima go out on a limb here, and predict that this La Nina will be the start of a new Little Ice Age… ;-)
References and further reading
ENSO wrap-ups - archive of ENSO reports from the Bureau of Meteorology (BoM)
About ENSO Outlooks - explanation of ENSO outlooks at BoM
Gobbling up or Spitting Out Bob Tisdale's ENSO Leftovers at WUWT - probably the most detailed HW article about ENSO, January 2014