I just know it was all they talked about, about 20 years ago.
Every seven (-?) years or so, prevailing winds come off the Pacific. And we have El Niño. A very mild winter.
The only thing is, they have stopped talking about it. So now I and we don’t know when we will have another El Niño. And I don’t know about the rest of you. But I would really like to know.
When will the next El Niño be?
And not to confuse matters. But there is also something called La Niña. I have no idea what it is. So first of all, what the heck is it, and when will it be too?
It isn’t talked about much any more because it is routine now. 20 years ago the idea that some cold water off western south america meant anything to anyone except the local fishermen was controversial. Now it is fully accepted, you don’t hear as much about it.
But it continues to happen, as it always has. As for when the next one will occur, no one knows for sure. It comes on average every 7 years (actually more frequently, but the strength varies, a fairly strong El Nino occurs every 7 years or so).
El Nino is due to the southern oscillation. Here is more than you probably want to know about the SO:
Driven by long-term winds, the surface waters in the tropical pacific slosh back and forth. When it is warm in the west, it is cold in the east: El Nino. When the slosh gets back to the east it is warm in the east: La Nina. Back and forth like waves in a bath tub. Driven by the winds, the period varies.
El Nino is something that climatologists can’t predict with great certainty (particularly months in advance), but one does see news articles in which the U.S.'s Climate Prediction Center will be predicting the likelihood of a strong El Nino (or La Nina) effect for the year.
The Wikipedia article on El Nino indicates that the CPC classified the following years as having El Ninos (the dates are two-year ranges, because it occurs during the late fall and winter in the Northern Hemisphere):
1982-83
1997-98
2002-03
2004-05
2006-07
2009-10
2014-15
2015-16
Of the above, 1982-83, 1997-98, and the 2014-16 two-year event are classified as “major El Nino episodes.”
Note that different countries’ climate agencies have different criteria for declaring if El Nino is going on (or not), and so, the above is what the U.S. agency declared.
It should also be noted that current El Niño predictions are fairly difficult: recent ocean conditions in the North Pacific are unexpected based on our understanding of the workings of the El Niño Southern Oscillation & Pacific Decadal Oscillation, so predictions at this stage are both more honest and more uncertain than they would have been ten years ago.
The effects of El Nino and La Nina differ depending on where you live. In the PNW, El Nino means drier and warmer winter, while La Nina means wetter and colder. In other parts of the US, it’s the opposite.
