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Thursday, May 19, 2016

El Niño to La Niña years

Sou | 12:46 AM Go to the first of 5 comments. Add a comment
I said a short while ago that I'd look at what has happened in the past when a La Niña followed a strong El Niño. Well, I have, and here is the result. These are all the strong El Niño's that were followed by a La Niña in recent decades. There were only three of them. In two cases, the following La Niña was a multi-year event as shown in the figure below. The surface temperature data is from GISS NASA. The Nino 3.4 sea surface temperature data is from NOAA and the ENSO years are from BoM.



For comparison, the chart below shows just the sea surface temperature anomalies just for the Niño 3.4 region for the same four periods.


If you line them up, it looks as if the minimum global surface temperature lags the ENSO 3.4 anomaly by not much at all for La Niña, though the maximum usually lagged El Niño by about 3-4 months, except for the 1972-73 El Niño.

I checked the timing of the minimum and maximum temperatures, which you can see in the table below. The La Nina that followed the 1972-73 El Nino dragged on for a long time and the minimum temperature wasn't till February 1975. It was cold in 1974 as well, but not as cold as the following year. Seemed best to leave the "lag" calculation blank for the 1973-76 La Niña.





From the HotWhopper archives


5 comments:

Lars Karlsson said...

In the last table, I suspect that "Nov 98" should be "Nov 97", and "Feb 15" should be "Feb 16".

Sou said...

Thanks, Lars. Fixed now.

Nick said...

1982-3 was of course a strong El Nino, but was only tardily followed by a weak la Nina starting late 1984.

You could only class 1987-88 as a moderate El Nino, while I do remember the effects of the strong La Nina that followed: April 1988 and April 1989 in my area were two of the wettest recorded, with 900 to 1000mm in those months.

April this year was the driest in almost thirty years.

Baseline protocol for ENSO 3.4 anomalies I assume is the Nino 3.4 one described here:
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_change.shtml

Sou said...

I probably should have clarified. The years I picked were the only very strong, strong, and strong to moderate El Ninos that were immediately followed by a La Nina.

Since 1950, there were seven very strong, strong, and strong to moderate El Ninos (not counting 2015/16), and only three of these were immediately followed by a La Nina.

Sou said...

See here (linked above, too):

http://blog.hotwhopper.com/2016/03/anthony-watts-sticks-his-neck-out-and.html