ENSO Wrap-Up: Tropical Pacific neutral; chance of La Niña increases
Issued on Wednesday 26 May 2010 | Product Code IDCKGEWWOO

Climate indicators across the equatorial Pacific are currently neutral. Equatorial Pacific Ocean temperatures, trade winds, the Southern Oscillation Index and cloudiness over the Pacific are all at levels considered typical of neutral conditions (i.e. neither El Niño nor La Niña).

Historically, about 35~40% of El Niño events are followed by a La Niña within the same year. Currently, a large volume of cooler than normal water is present below the surface of the equatorial Pacific Ocean, which indicates that further cooling of the surface of the tropical Pacific is likely.

International climate models predict continued cooling of the Pacific Ocean sea surface, with the majority of models surveyed by the Bureau predicting that this cooling will be sufficient to see the development of La Niña conditions later in the year. No climate models suggest a return to El Niño conditions. It should be noted that correctly predicting transitional periods of the El Niño Southern Oscillation is more difficult than predicting the continuation or decline of El Niño or La Niña events.

I always thought we wanted to see el nino conditions on the East Coast to increase the strength and frequency of North Easterlies through summer? Always felt a bit guilty as it generally means drought and bushfires to the rest of the population, but I was dealing with it.....

Since it's been pissing down for the last 2 yrs, how are we not in a La Nina, and if not, does that mean it's all bogus anyway ?

Now, I have not followed this thing terribly closely, but on the few occasions I have taken notice of what the predictions were, they have been wrong.
That said, I'd love some more big southerlies thanks, but only after a cracking season of north wind !!!

PS I'm in considerable pain today after training a bit for my Maui trip, in case anyone is feeling unsympathetic and wants to bag me out for my trouble !!

Mobydisc said...

May be good for Queenslanders but for NSW it means more wet summers with the usual doldrums. As Ken says, its was a wet and ordinary summer this year. There were decent seabreezes up till Christmas Eve but after that, bugger all until sometime in March.

Not just NSW. When I was in Bundaberg in March, the rivers were all running brown with huge flood run-off, and Gin Gin in May looked like the garden of Eden, when it normally looks like South Dakota badlands.
I seriously could not see the cows in some paddocks because the grass was well over their heads, and farmers were slashing roads for them. Usually you can't see the buggers unless they stand side on and you squint to see through the dust and the heat haze.
If that's El Nino, I'm a vegetarian.

what about the south coast my friend??

^ i don't know what it means for the south coast during la nina. last la nina we had the WA crew had an ordinary season though from what was posted on seabreeze.

how has the last 2 months been for you?

this is what it means for south australia

Sea surface temperatures in the Pacific Ocean can affect rainfall right across Australia, but their most direct link is to rainfall in the eastern half of Australia.

The El Ni?o - Southern Oscillation (ENSO) is a major influence on Australia's climate, though its effect is less marked over much of South Australia than for areas further east.

ENSO is the oscillation between El Ni?o and La Ni?a conditions, interspersed with neutral periods.

These events are triggered by variations in sea surface temperature in the central and eastern tropical Pacific Ocean.

and the link -

http://www.climatekelpie.com.au/understand-climate/weather-and-climate-drivers/south-australia

plus this

www.bom.gov.au/lam/climate/levelthree/ausclim/ausclimsa.htm

last 2 months not memorable,typically autumnish,the odd windy day.
our wind at the moment is from cold fronts-sthwestlys and high pressure systems creating northerlywinds--if the centre of the highs sit around central aus we usually have good northerlys--if they sit lower we dont.
rule of thumb here is in winter,if we have good weather,sunny skies,you have crapp conditions in qld,ie--plenty of wind.--and vice versa

The big thing here is that looking at factors like ENSO, and sea surfaces temps etc, is to try and predict weather at a "complicated" level, much like a car at rest. It's a complicated mechanism.
However, weather is not complicated, it is "complex", like a car in motion, where the parts of that complicated mechanism starts interacting with each other and the surrounding environment.
Weather is also an emergent system, meaning, that even though it is governed by a consistent set of rules, there are so many rules interacting with each other, that you have to run the system to see what will actually happen rather than be able to predict what will happen.
Smarter people than me have defined about 3 days as the limit before predictive models start disintegrate in the exponential explosion of permutations and combinations.
Put more simple it's like trying to shoot charlies when playing pool. Looks simple, no-one has ever done it.

And I thought it was just about those red and green arrows.

I think I may be a bit simple because the most I can understand is if the arrows show red then it definitely isn't any good and if the arrows show green then it probably isn't any good

Do you record what days you sailed and what it was like to compare forecast with actual ?

Or do you just sort of remember each time and draw a general conclusion.

Would it help if everybody recorded where they sailed and what board / sail size they used ?

Is that too anal, or giving away too many secrets, or just a waste of time ?

I've always noticed that if it is a wet autumn, then it tends to be a mild winter, implying fewer strong south westerly winds
Last year as an example.
Does that gel with things ?

KenHo said...

I've always noticed that if it is a wet autumn, then it tends to be a mild winter, implying fewer strong south westerly winds
Last year as an example.
Does that gel with things ?

i got nothing.

i can't answer that. there is a lot of research currently going on into the relationships between inter seasonal weather patterns. but it's early days and i don't know what the outcomes are.

the 2 big drivers of autumn rainfall in SEQ are the indian ocean dipole and la nina, both would bring warmer moist air i think which mixes with fronts and troughs and causes rain. how that relates to winter i don't know. the timing of the start of la nina or a negative dipole would be more important i would think.

this guy http://web.maths.unsw.edu.au/~matthew/swwa_rainfall.htm has recently done some studies and seems to be indicating there is a connection. indicating that droughts over SW WA would mean cold winters in SEQ. but i could be interpreting that wrongly.

the la nina and indian ocean dipole are seasonal patterns and the SAM is a shorter 14 day cycle. so you could have multiple +ve and -ve SAM's in a season. it's probably the combination that increase or decrease rain fall.

i guess.

are there any meteorologists out there?

And the biggest SE winds come when there is a low up north and a high down south just touching at the edges. THe area at that conjunction really gets windy !!
We used to get that in Bundaberg a bit, and it produced a lot of wind.
One year, I sailed small gear every day for over 3 weeks.
Maybe that year or the next I used a 4.0 over 20 times in a late summer/autumn period.

Gestalt said...

^ yeah, bring it on!

That's the sort of conditions you need to really get Burrum Heads hammering for some really huge speed times.

Just before that cyclone event, someone on here posted that a cyclone is often followed by a windless period. I recall thinking they had been right.
A big clonic stirs up a lot of cool water sometimes, if it sits in one place.
I remember a whopper out near Fiji that just sat there and died in a puddle of coolwater of it's own making.
I would also take cyclones out of the usual modelling, because they say more about specific conditions conducive to low formation than they do about highs.
Conditions vary a lot over a relaively short distance too. When I was in Bundaberg, I asked the locals what sorts of northerly season they ahd, and they said it was pretty ordinary. That contrasts pretty strongly with the great season we had a few hundred km away.