Post by Weatherlawyer Post by Alastair Post by Ron Button
Would somebody out there be willing to translate this into English... ?
I assume you mean British English?
El Ninos happen when the Trade Winds falter, and the warm equatorial
water they have blown into the (southeast Asian) Warm Pool floods back
across the Pacific mainly to the west coast of South America. This
disrupts the Walker circulation (a series of high and low pressure
regions spaced around the equator) and so affects weather around the
Pacific and Indian Oceans, with inevitabley collateral damage in the
With a La Nino, the water off the South American coast is unusually
colder than normal, the opposite to an El Nino. The global effects of
a La Nina are not as noticable as those of an El Nino, but do affect
the US especially its west coast. The American, Alan Reppert, thinks
that the current La Nina will also affect the western European climate
but does not know by how much or even how!
Any corrections to the above remarks would be welcome.
Nice try. My take was to switch off when I realised he was talking
about an average of half a degree. The average is itself an average so
his fallacy in trying to insinuate such a thing into a weather model
As you, say the anomaly is based on air pressure and to say that it is
the winter months that are important in the system is also ridiculous
as the anomaly is present (or can be seen) in summer too, in fact any
and all of the months.
Negative NAOs can be seen with major volcanic eruptions. Or at least,
the spate of them that occurred in the last negative NAO led me to
suspect that. There was nothing noticeable on the charts when that
Yemeni mountain erupted.