El Nino has started

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NZstorm
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El Nino has started

Unread post by NZstorm »

According to NOAA
NOAA expects this El Niño to continue developing during the next several months, with further strengthening possible.
http://www.noaanews.noaa.gov/stories200 ... lnino.html
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TonyT
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Re: El Nino has started

Unread post by TonyT »

This is somewhat open to misinterpretation, because NOAA's own official definition of a fully fledged El Nino event is 5 consecutive 3 month averages > 0.5degC above normal, June is just the first of the five, so NOAA cant really call it an El Nino event yet, and wont be able to until the October numbers come in.

Interesting that as NOAA release this statement the SOI (see http://www.bom.gov.au/climate/enso/ for a graph) is now trending back past zero and into La Nina territory. This is looking more and more like a psuedo-El Nino to me.
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Re: El Nino has started

Unread post by RWood »

The PDF in

http://www.cpc.ncep.noaa.gov/products/a ... ts-web.pdf

is still talking about a transition from neutral to El Nino conditions in the tropical Pacific, so I guess it is not quite "committed" yet in that document.
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Re: El Nino has started

Unread post by Michael »

Hopefully No to a spring elnino it delays our summer.
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Re: El Nino has started

Unread post by Myself »

Jim Salinger in his new position did put out a Spring forecast, and I think it said cold with plenty of southwesterlies.
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Re: El Nino has started

Unread post by Vertigo »

i thought june was the coldest june in recent years?
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Re: El Nino has started

Unread post by TonyT »

Not in the tropical waters of the central Pacific!
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Re: El Nino has started

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:B of course
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Re: El Nino has started

Unread post by NZstorm »

I heard Jim Salinger on the radio today mentioning something about an unsettled spring on the way for NZ. I didn't get the full story but it was basically referring to an El Nino spring/summer for NZ, drier in the east.

My own thoughts on the upcoming El Nino is that the chance of severe hail/thunderstorms will be higher than normal over the west and east of the South Island, and also the east of the North Island. I suspect a north Tasman Sea ridge will keep things very stable over the north of the country, hope i'm wrong on that though.
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Re: El Nino has started

Unread post by Nev »

Yes, but the typical El Nino pattern, i.e. cooler, more frequent or stronger SW'ers in spring and more frequent or stronger W'erlys in summer, looks only likely to be weak to moderate at this stage (if at all).

Here's an excerpt from NewsRoomAmerica.com about today's WMO report...
El Nino Weather Pattern Likely To Continue Into 2010
2009-08-19 11:36am

...The UN World Meteorological Organization said today that sea-surface temperatures in the eastern equatorial Pacific had risen to between 0.5 and 1 degree Celsius warmer than normal by the end of June, with similar temperatures in July.

"Scientific assessments of these observations indicate that this warming resembles the early stages of an El Nino event," the Geneva-based agency said.

"Although some of the atmospheric changes associated with this warming have been initially slow to develop into classical El Nino climate patterns, the warming is now well-established enough for scientists to conclude that it is consistent with a basin-wide El Nino event." ...
However, Australia's BoM appear to be taking more of a wait-and-see approach in their ENSO Wrap-Up yesterday (El Nino has a greater affect on them than us). ...
A regular commentary on the El Niño-Southern Oscillation
CURRENT STATUS as at 19th August 2009

Summary: Mixed El Niño indicators as development slows

The El Niño pattern across the Pacific has not intensified during the past fortnight. Furthermore, the coupling between the ocean and atmosphere which amplifies and maintains El Niño events has so far failed to eventuate. The neutral SOI and sub-surface cooling are evidence of this.

However, the Trade Winds are weakening over a broad area and this may promote renewed warming. In addition, leading climate models continue to predict further development of the El Niño, although not as emphatically as a month or two back. Therefore, the odds remain strongly in favour of 2009 being recognised as an El Niño year. ...
Also, here's Unisys's Current SST Anomaly Plot graphic.
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Re: El Nino has started

Unread post by NZstorm »

Obviously my prediction is based on an El Nino occurring. We are due for one anyway. Time will tell I guess.
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Re: El Nino has started

Unread post by Manukau heads obs »

if you go by the 11 year sun spot cycle, the next big round of el nino years will be around 2015 or so :)
(and those big el nino years are usually preceded by some big la nina years...from my reckoning..so we might still have a 1 or 2 more la nina summers to come yet over the next few years.....time will tell!
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Re: El Nino has started

Unread post by NZstorm »

to add to the 'El Nino when you are not having an El Nino', this from the WMO:
In its most recent update on the subject, WMO stated that the expectation is for El Niño conditions to very likely prevail through the remainder of 2009 and into the first quarter of 2010.

“This expectation is based on model forecasts, and the typical life-cycle of El Niño events, which once established in the early-middle part of a year, usually persist through into the first quarter of the following year.”

The agency added that El Niño typically occurs once every four to five years, so the current assessments translate to a “substantially” elevated risk of an El Niño developing later this year.
quoted from this link http://www.scoop.co.nz/stories/WO0908/S00328.htm
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Re: El Nino has started

Unread post by Nev »

Yes, a weak to moderate El Nino does seem likely, with slightly cooler waters around western South America and warmer waters around the in central and eastern tropical Pacific. However, not all indicators totally confirm an El Nino scenario, as pointed out by the BOM...
A regular commentary on the El Niño-Southern Oscillation
CURRENT STATUS as at 19th August 2009

...In Brief
* The sea surface remains significantly warmer than the long-term average across most of the tropical Pacific Ocean, exceeding El Niño thresholds in central to eastern areas.
* The sub-surface water of the tropical Pacific cooled through July and August. However, a large volume of the sub-surface water still remains significantly warmer than the long-term average.
* The latest 30-day SOI value is −4; the monthly value for July was +2. These SOI values are near neutral and do not show an El Niño trend.
* While Trade Winds have been consistently weaker than normal across the western equatorial Pacific in recent months, they have fluctuated over the central to eastern equatorial Pacific, with weakening observed recently.
* Cloudiness near the date-line has recently been slightly below average. Cloudiness near the date-line is usually greater than average during El Niño events.
* Six of the seven leading international climate models surveyed by the Bureau predict the tropical Pacific to continue to warm and to remain above El Niño thresholds for the remainder of 2009.
Confused :?: :-s

El Nino has been pretty much the norm over the last 30 odd years btw...
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Re: El Nino has started

Unread post by jrj »

Is this the same Jim Salinger who predicted a mild winter? :wave:
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Re: El Nino has started

Unread post by RWood »

James wrote:Is this the same Jim Salinger who predicted a mild winter? :wave:
The relevant quote from the NIWA June-August outlook: "Temperatures are expected to be near average in most regions, but average or below average in the east of the South Island."

(in more detail: "average" temperatures were given a 50% probability for all regions; 30% warmer, 20% cooler for all ragions except the east of the South Island where the numbers were 20% warmer, 40% cooler).
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Re: El Nino has started

Unread post by Michael »

The Junk under W.A thats been there for the last week or two which no doubt will come here at the end of the month looks very El nino ish.
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