*EL NINO/LA NINA FORECAST 2010-2011*

[karlox]

Thanks Nautonnier for taking your time to teach Basic Climatology to ´beginners´ as me....
Yet I don´t quite understand whether the heating or cooling of certain areas of Central and South Pacific Ocean waters is what might drive either to a ´mostly´Negative or positive AO and NAO index or not; in other words, a negative phase of AO index is commongly associated to a negative phase of NAO index (I think here the pressure difference betwen Island and Lisbon is what counts).

Then, could we say that a sustained, important negative AO/NAO index phase- as it has been for the last months starting at the end on november- would be roughly linked to EL NIÑO phase, while prevailing positive AO/NAO index would normally be associated to La NIÑA? (just for an example to explain my question, not that I believe that, simply don´t know)

I guess that long-term statistic data comparing AO/NAO index with ENSO/SOI, plus some ´data math cooking´ could establish -or not- such trend and/or association; I simply have not either the knowledge nor the skills to find out, but if there is such a clear and close response for both phenomena then for sure either you Nautonnier or someone else out there have an answer for me... thanks in advance

[nautonnier]

Feb 14, 2010 7:36:52 GMT karlox said:

Thanks Nautonnier for taking your time to teach Basic Climatology to ´beginners´ as me....
Yet I don´t quite understand whether the heating or cooling of certain areas of Central and South Pacific Ocean waters is what might drive either to a ´mostly´Negative or positive AO and NAO index or not; in other words, a negative phase of AO index is commongly associated to a negative phase of NAO index (I think here the pressure difference betwen Island and Lisbon is what counts).

Then, could we say that a sustained, important negative AO/NAO index phase- as it has been for the last months starting at the end on november- would be roughly linked to EL NIÑO phase, while prevailing positive AO/NAO index would normally be associated to La NIÑA? (just for an example to explain my question, not that I believe that, simply don´t know)

I guess that long-term statistic data comparing AO/NAO index with ENSO/SOI, plus some ´data math cooking´ could establish -or not- such trend and/or association; I simply have not either the knowledge nor the skills to find out, but if there is such a clear and close response for both phenomena then for sure either you Nautonnier or someone else out there have an answer for me... thanks in advance

"Yet I don´t quite understand whether the heating or cooling of certain areas of Central and South Pacific Ocean waters is what might drive either to a ´mostly´Negative or positive AO and NAO index or not; in other words, a negative phase of AO index is commongly associated to a negative phase of NAO index (I think here the pressure difference betwen Island and Lisbon is what counts)."

The problem when you have interrelated systems where there are also external events and drivers is that people get taken up with an interaction in one direction and claim it is 'the cause' when it itself is being caused by the interaction in the other direction.

So the El Nino is 'caused' by the drop in the trade-winds that allows the warm surface water of the West Pacific to move back Eastward (in a Kelvin wave) leading to warmer sea surface temperatures in the East Pacific. The warmer sea surface is therefore a symptom of the drop in the tradewinds the warmer sea surface itself may lead to changes in convection and humidity in the equatorial pacific. The strength or weakness of the trade-winds (the Hadley Cell) is currently measured by the pressure differences between Tahiti and Darwin.

Why does the pressure difference change and why did the trade-winds drop in the first place?

Well that is usually because the convective circulation in the Hadley Cells has changed for some reason. If you look at the diagram in the previous post imagine the effect of the arctic polar vortex changing and moving south and compressing the Ferrel and Hadley cells toward the equator. This compression results in less poleward transfer of heat and more vertical transport of heat. The width and strength of the Hadley cells will be altered and result in a tradewind change and the effect on ENSO. BUT this change was caused by the change in the polar vortex.

There are similar effects for the NAO only here the winds invvolved are the Westerlies that are part of the Ferrel cell circulation. Metrics for this are pressure differences between Iceland and the Azores - or the strength of the anticyclone caused by descending air from the Hadley cells and the North of the Ferrel cell.

What causes these pressure values to alter?

Again an equatorwards movement of the polar vortex squeezing the Ferrel cell. This may be an overall expansion of the polar vortex or as large weather systems can deviate the jet stream southward.

This is a very complex area as it is looking at the fluid dynamics of the atmosphere interacting with the fluid dynamics of the ocean and all in differential rotation as the Earth rotates with tides pulled in both fluids by the moon.

For example see:

Daily North-Atlantic Oscillation (NAO) index: Statistics
and its stratospheric polar vortex dependence

www.fastopt.com/papers/blessingal05.pdf

To sum up - something causes the polar vortex to alter causing a cascade of changes in the other circulation systems. Dependent on their current state this may be short lived or alter the circulations to a different state for a while before they return to the previous state. This is classic chaotic behavior the normal state is a strong attractor but given inputs at the right time oscillations can move away to a less powerful attractor (set of states ) until they return to the strong attractor.

Something changes and the polar vortex and Ferrel and Hadley cells are affected. This can lead to a state change in the NAO and if the timing is right may also lead to an El Nino.

The 'something' that changes could be a Sudden Stratospheric Warming which can be thought of as a wave in the tropopause breaking as it reaches the pole. This can totally disrupt the jet streams which run along just under the tropopause, breaking them up and even causing the polar vortex to temporarily reverse. If this happens at just the right time - there may be longer lasting effects on one or all of the polar vortex and the various oscillations.


Anyone who reduces the weather and ocean systems to simple measurements of pressure differentials is looking at these phenomena in a VERY narrow way and misses the extreme complexity of their causation and effects.

[karlox]

Nautonnier, you´ve brightly summarized -and conveniently put together- most of the information I was looking for in order to improve my understanding of Climate and weather oscillations. Still got lot of room and need for more learning -and feel lucky for that- but your post is quite a good guideline for me now, I especially appreciate your effort since I know a lot of what you tell me has probably been commented here and there by you and others through different threads. Now is my time again to ´study´a little bit more... new questions shall arise and I feel lucky I could find highly expertise voices such as yours in this forum.
Coming week or lots of rain and some snow here in Spain, especially western, Central and Southern parts: NAO index keeps on minimums negative data during this part of february...

[throttleup]

Likewise, Nautonnier, I just want to add my thanks for your effort to explain and enlighten. The whole effort to understand the climate pieces and relationships between them is difficult and time-consuming for the beginner and professional alike.

I appreciate the insight and information you and others bring to this board.

[nautonnier]

From Joe Bastardi's European Weather Blog....

"Notice the reaction the next month or so to the current neg SOI burst, which is about to change, btw and then all the new runs showing the nino falling apart

You wait, the warm winter in the east next year or the year after will be blamed on global warming and they will ask you to ignore the overall earth temp which will be cooling!!!

That too seems to be predicatable."

www.accuweather.com/ukie/bastardi-europe-blog.asp

[solarstormlover54]

It seems El-Nino flared up a bit on Feb 10 towards the east.

+0.5 anomaly seemed to dissipate off the coast of South America, but is now starting to come back.

Not sure if it's reviving or simply a dieing breath. Most likely the dieing breath

[sigurdur]

Feb 16, 2010 2:46:07 GMT solarstormlover54 said:

It seems El-Nino flared up a bit on Feb 10 towards the east.

+0.5 anomaly seemed to dissipate off the coast of South America, but is now starting to come back.

Not sure if it's reviving or simply a dieing breath. Most likely the dieing breath

Astromet would say it is reviving. I am not so sure.

[AstroMet]

Feb 16, 2010 3:24:14 GMT sigurdur said:

Feb 16, 2010 2:46:07 GMT solarstormlover54 said:

It seems El-Nino flared up a bit on Feb 10 towards the east.

+0.5 anomaly seemed to dissipate off the coast of South America, but is now starting to come back.

Not sure if it's reviving or simply a dieing breath. Most likely the dieing breath

Astromet would say it is reviving. I am not so sure.

By the end of February, and into early March, we should see an uptick in ENSO convections. This will then begin another round of heavy rains into the Americas. El Nino is far from over.

[solarstormlover54]

What is the chance of the El-Nino lingering the whole year.
The last time it did that was in 1987. A concern in my area as an F4 twister touched down just 25 miles from my town and hit a major city.

Whether the 1987 tornado has something to do with the "summer El-Nino" I don't know

[AstroMet]

Feb 18, 2010 21:01:29 GMT solarstormlover54 said:

What is the chance of the El-Nino lingering the whole year.
The last time it did that was in 1987. A concern in my area as an F4 twister touched down just 25 miles from my town and hit a major city.

Whether the 1987 tornado has something to do with the "summer El-Nino" I don't know

A very good chance. In forecasting ENSO for 2010 several years ago, astronomically, what I saw was a continued influence of El Nino through the winter season in the northern hemisphere (a powerful and snowy winter) along with flooding in both hemispheres from the increased precipitation. This is starting to happen now in Australia, and I've forecasted floods for the Americas in spring.

[woodstove]

Mar 7, 2010 23:54:43 GMT AstroMet said:

Feb 18, 2010 21:01:29 GMT solarstormlover54 said:

What is the chance of the El-Nino lingering the whole year.
The last time it did that was in 1987. A concern in my area as an F4 twister touched down just 25 miles from my town and hit a major city.

Whether the 1987 tornado has something to do with the "summer El-Nino" I don't know

A very good chance. In forecasting ENSO for 2010 several years ago, astronomically, what I saw was a continued influence of El Nino through the winter season in the northern hemisphere (a powerful and snowy winter) along with flooding in both hemispheres from the increased precipitation. This is starting to happen now in Australia, and I've forecasted floods for the Americas in spring.

Last I heard, you were predicting El Nino through the summer season -- at least.

You appear to be backing away from that.

As for predicting floods in "the Americas" in spring -- what else is new?

[dartman321]

Astromet:
I saw this latest update about ENSSSO from an Accuweather, Joe Bastardi post..."Let's put it this way. It supports the big hurricane season idea and supports the crash of global temps in response to what is going on now as we are back in La Nina later this year with it continuing through 2011 along with a noticeable cold PDO. At the very least, the model is seeing my idea on where the global temps are going, given the look this has because its much colder than the initial conditions. So we shall see. "

....this seems to cut firmly against your prognostication...

"I've forecasted 2010-11 to be a very strong El Nino year. This is caused mainly by the activity of the Sun, which will undergo an historic solar maximum that will bring to an end the 36-year global warming phase that began in the year 1980 while opening a new global cooling phase that will get underway by the year 2017.
and.."By this time in fall 2010, the Mid-Atlantic should be well within the throes of El Nino,.." and..."For over two years, I continued to forecast that a new El Nino was on the way from my astronomic calculations. This ENSO will dominate the world's weather events through all of 2010, into 2011 and 2012, "

We shall see. We shall see.

[neilhamp]

Latest ENSO wrap up report states:-

Computer models suggest Pacific Ocean temperatures will cool steadily over the coming months, returning to neutral levels during the southern autumn. Such timing is typical of the decay stage of an El Niño event.

[AstroMet]

Mar 14, 2010 22:48:51 GMT dartman321 said:

Astromet:
I saw this latest update about ENSSSO from an Accuweather, Joe Bastardi post..."Let's put it this way. It supports the big hurricane season idea and supports the crash of global temps in response to what is going on now as we are back in La Nina later this year with it continuing through 2011 along with a noticeable cold PDO. At the very least, the model is seeing my idea on where the global temps are going, given the look this has because its much colder than the initial conditions. So we shall see. "

....this seems to cut firmly against your prognostication...

"I've forecasted 2010-11 to be a very strong El Nino year. This is caused mainly by the activity of the Sun, which will undergo an historic solar maximum that will bring to an end the 36-year global warming phase that began in the year 1980 while opening a new global cooling phase that will get underway by the year 2017.
and.."By this time in fall 2010, the Mid-Atlantic should be well within the throes of El Nino,.." and..."For over two years, I continued to forecast that a new El Nino was on the way from my astronomic calculations. This ENSO will dominate the world's weather events through all of 2010, into 2011 and 2012, "

We shall see. We shall see.

Of course we will see. The weather and climate always validates or invalidates any forecast. However, I am not positive on Accuweather's long-range forecasting, since they don't have a good track record of forecasting that far out, and do not do so astronomically, which is the only sure way of knowing.

I forecasted this El Nino back in 2006, so, I am on target and on time. I expect the rest of 2010 to be an El Nino year, with the typical droughts and heavy rains, floods, etc., associated with ENSO, to be followed by La Nina in late winter (Feb. 2011) for North America.

I forecasted next winter starting late, after a wet, long, and warmer than normal autumn season, with winter arriving sometime in January 2011, and extending through February, March, and April 2011.

[AstroMet]

Mar 8, 2010 5:36:17 GMT woodstove said:

Mar 7, 2010 23:54:43 GMT AstroMet said:

A very good chance. In forecasting ENSO for 2010 several years ago, astronomically, what I saw was a continued influence of El Nino through the winter season in the northern hemisphere (a powerful and snowy winter) along with flooding in both hemispheres from the increased precipitation. This is starting to happen now in Australia, and I've forecasted floods for the Americas in spring.

Last I heard, you were predicting El Nino through the summer season -- at least.

You appear to be backing away from that.

As for predicting floods in "the Americas" in spring -- what else is new?

I don't know what you heard, but I have El Nino though the entire year of 2010 - not just through summer. I also forecasted floods in my long-range forecast for this spring before anyone else did last year. I don't see where I'm "backing away" from anything?

Read my forecast again. I remember back in 2006, 2007, 2008 when nearly everyone did not think El Nino would be on tap by late 2009 and 2010. I was the one who forecasted the return of ENSO.

I continue to state that this year will be a major year of global weather for at least half the planet, and that this will continue through 2010, and into 2011 with the onset of La Nina, as well as a later than normal winter season for the northern hemisphere that doesn't really get going until about February 2011 and extends into March, and April of next year.