Nino 3.4 Index was +0.73C last week.

I consider anything over +/- 0.7C to be the start of an El Nino/La Nina (although a case be made it should be +/- 0.8C or 0.9C).

The official definition is a 3 month average in Nino 3.4 over +/-0.5C but if you look through the record, it is the events that get over +/- 0.7C that turn into real longer-lasting events where you can actually say this was a La Nina or an El Nino. There are lots of 0.5Cs that just reverse in a short period of time or stabilize at that level and these should be called neutral. You can actually count the ones that get over 0.7C for a 3 month period while you would have a hard time counting the 0.5Cs.

In addition, the global temperature impact from the ENSO is anywhere from 0.07 to 0.200 * Nino 3.4 (lagged three months) depending on how many other variables you control for (like volcanoes etc.) So the temperature impact from a 0.5C event * (0.07 to 0.200) is only 0.035C to 0.100C which is nothing to get worked up about. Its too small to even be noticed really.

El Nino to return
Wednesday July 4, 2012 - 06:51 EST

The Bureau of Meteorology is forecasting a dry season as the region enters an El Nino weather pattern.

During June, sea surface temperatures in the Pacific Ocean were about half a degree warmer than usual.

Climatologist, Acacia Pepler says it is an indicator that the western region will have a drier than average winter and spring and a warmer than usual summer.

She says there is no way of telling how severe the dry spell will be or how long it will last.

"Most of the models are thinking it's going to be a weak El Nino event although there's still a lot of variation between the different runs they do," she said.

"However, El Ninos are a bit less simple to than La Ninas in terms of impact.

"It very much depends on what happens during the events.

"We can't say right now how big the impacts will be."

However, she says a potential drought could be avoided due to a different weather cycle also impacting Australia.

"One of the things that's going on at the moment is that we also have very warm sea surface temperatures in the Indian Ocean off WA and those tend to give a much increased rainfall across Australia so that might act to moderate the impact of the El Nino if we're lucky."


- ABC

weatherzone

posted on WUWT thread, I have agree with him that this very weak El Nino will break up, I even think quicker than he says. We shall see anyway.
anyway, you wanted Joe, here he is....

"Joseph Bastardi says:

July 3, 2012 at 3:48 am


Typical cold PDO nino which will spike in mid winter, then fall apart. Joe D Aleo did extensive work on this. Its why last year I knew Nina was not over, and was yelling loudly in winter it El nino will come on, peak, and go. Posted on this several times from before hand! This has a chance to mimic such winters as 02,09,76 where if you look at mei, enhanced cold periods before hand of at least 2 years, were followed by flip, that set off winter. Theory on this: la nina signal cools overall globe, but leads to pressure rises over Pacific falls over US because enhanced nina jets drive trough into western US, opening US up for broad southwest flow and higher than normal pressures ( storm track well to north) This year it was like it was on steroids, very much like 75-76, When nino comes on, cold pdo overall attacks it and we see the warm water come off S America early and cool toward the winter, while the cent pac warms. this can be seen in forecasts already of nino3.4 and 1.2 Such an event enourages PRESSURE FALLS in tropical pacific, compensating winter rises over the areas of N America that were abnormally low in the la nina, ( central and north) and once sets a source region for the southern storm track and high pressures to the north in the means

I have been posting this theory, along with 400 mb shut down theory on tornado and hurricane season before the fact since the winter, as the winter and research debunking IPCC hot spots really opened my eyes to some things. In any case, this is a real time test for all to see ( tornado theory, that the season would crash looks good and the idea behind hurricane forecast was fast start, and the worry has to be in close development in a low ace season in the atlantic overall. BTW both those ideas were presented at ICCC7 to make sure that others saw them before hand.

IN any case another interesting aspect, and we are covering this on weatherbell, is the negative aao in their winter, similar to 02/09 which is a precursor to our ao in winter. Another test, but this one was inspired by the people at METSUL, who have shown Joe D Aleo and I enough evidence to at least have us, and now you and again test it in real time!

You cant hide declines, fudge or adjust data, or run from errors when one tests in real time. More exciting and really though it stings when wrong, the real way to have things peer reviewed! Would take WUWT readers any day for that"

Great post BD - had not spotted that and love to hear what Jo bastardi has to say.

My pleasure BNE, I thought of you as soon as I saw his post, knowing that you had asked about him previously. Cheers

Gee , BOM don't do themselves many favours .... the Headline doesn't really reflect the release ....
They go with " El Nino " warning , and then later on there's mention that they aren't expecting typical Nino Dry conditions .....
From the same Government that is now " Alarmed , Not Alert " at AGW .....

yeah , whatever fellas' . As Joe , BD and others within this discussion , the talk may now go from how strong this Predicted Nino will get , to how short it will last ...

Not sure if you noticed but the article you quoted was from the ABC - they thought up of its headline as well as the opening sentences, not the BoM.

It's also worth remembering that there's often a big difference between what official organisations like the Bureau say & the headlines/articles in the media. Things can often be oversimplified & put out of context in the name of making headlines/articles in bite sized chunks easily digestable by the general public.

Ken ,

I know its written by ABC . But the quotes of BOM and Acacia , the full article is a Total contradiction . Not to mention that they have Included Winter in their Dry Forecast , which last time I checked Winter is nearly Half Done , and the First half has been slightly above average Wet .

So what i was saying is that i was in more of an Agreeance with BD and Joe . Acacia touches on it . But the whole statement and Article is an Oxymoron .

Very similar to the AGW Predictions of a few Years back ... " Its Going to be Hotter and Wetter , and also Cooler Dryer " .... What The .. !?

Next thing you know the Proverbial " Weather String " will be showing AGW ..... ie : " The String took to itself with a Pair of Scissors " , as it feared getting wet , cold Burnt , blown , sunburnt and frozen .......

I can't see how it's that much of a contradiction. The takeaway message I get is that models suggest things will probably drift towards El Nino'ish territory albeit maybe weak, which traditionally causes drier than normal conditions (mainly around northern & eastern areas) by Spring... but it could be dampened by other effects.

It's been wetter than normal over a broad swathe of QLD & coastal NSW & VIC so far this winter but drier than normal for southern inland NSW & northern VIC (see http://www.bom.gov.au/jsp/awap/rain/inde...=month&area=nat). It's worth remembering, we haven't even reached halfway into winter yet. Trying to predict what it'll be like for the 2nd half of winter & spring simply based on the last few weeks would just be a form of nowcasting given things can change suddenly.

As for "also cooler and drier", not sure where you read that. The consensus is an overall increase in longterm temps averaged over the world & the potential speed-up of the hydrological cycle leading to a increase in the intensity of individual extreme rainfall events. The vast majority of modeling goes for continued decreased rainfall for southwest WA (averaged over decades) but it's not as clear-cut for eastern Oz with some suggesting a possible increase in warm-season rainfall for some areas. It's a shame so many things in these types of debates get taken way out of context, turn into a classic case of chinese whispers which many people then take for gospel.

Anyway will be interested to see how the next few months unfold with ENSO.

Ken ,

I take it you haven't seen what the models are cooking up for mid to late next week in Nth Vic / SW NSW ........

It's like as soon as they call one thing " officially " , Hughie goes and throws a Spanner in the Works ...

This year in SW WA is bucking that " Trend " Also ....

That's just it though Southern Oracle, every time an area experiences a weather event (cold snap, heatwave, wet spell, etc) that goes against any longer term overall trend, talk always arises about doubts regarding that trend. As soon as that weather event/s finish for awhile, that talk goes quiet. There's always going to be individual or even a series of weather events that buck any long term trend. A long term trend is exactly that - long term. The article clearly states that there's uncertainty regarding the severity & location of the effects of any El Nino that might occur. This is the case with all El Nino's, La Nina's & broadscale longer term oscillations. The effects vary with location & each event.

It's a bit like me going to Cairns for a single weekend during the Wet, experiencing fine dry weather and concluding that must be what Cairns is like all year. BTW I'm not saying for a moment that the recent winter rains won't continue til late winter. There's anomalously warm SST's out in the Coral Sea atm so there's a fair chance there might be more rain events before late winter. But I do think they'll ease to more neutral conditions at least (& perhaps drier than normal) for SOME areas of eastern Oz by late winter/early spring given the model outputs, El Nino type trend & setups in recent years. I'd love to be proven wrong on this though because I just planted some new trees!

You can look up any credible long term map or time series graph of rainfall in southwest WA and not miss the long term decline in rainfall over decades.

As for what the models are saying for next week, yes I have been watching it. I actually posted about this potential rain event in the SE QLD/NE NSW thread earlier this week (the output my script spat out earlier this week for the 2nd week of Jul using GFS ensemble data: http://i1172.photobucket.com/albums/r566/ahokay1/GoogleEarth_GrADS_Precip50mm.jpg)

El Ninos and La Ninas are solar cycle driven in the main as per my last article and more on that that will follow. Nothing to do with CO2!

Only my opinion guys but here we go this is what I think... Both the 2002 & 2006 El Nino crippled Australia in drought and both El Ninos weren't strong but the 2 main ingredients that caused widespread drought IMO for Eastern and SE OZ was the fact for both Years waters were warmer than normal near the dateline along the Equator (yet to see with this El Nino due to the strong Cold PDO in the North Eastern Pacific) And Positive IOD.
2009 had mixed results for SE Australia in particular July & August weren't to bad for Victoria more good rains in September while all these 3 months Qld and alot of NSW remained very dry which of cause came to a flashpoint at the end of September of that Year with huge duststorms, mostly dry weather returned October in most areas but November after a long heatwave for SE OZ saw some good widespread rains that followed towards the end of that month.

Of course after Christmas was the beginning of the end of the El Nino with one rain/storm events after another for the rest of that Summer for Eastern OZ. Anyway my point being there were mixed results that Year in SE OZ from July to November due to the fact the IOD stayed Neutral that Year BUT Qld and NSW were gripped in drought moreso cos the waters around the dateline were warmer than normal.

This Year the ssts are struggling to warm up near the dateline and to be honest I can't see much more warming through that area due to the Cold PDO pushing colder water down mixing from the NE which is allowing mostly the Coral sea to stay warmer than normal and pushing good Easterly trade winds onto the North Queensland coast and into PNG. Which to me means Qld and NSW shouldn't be gripped by a severe drought YES there be dry periods but I think there still be some timely and handy rain events over the next 3-5 months unlike the previous 3 El Ninos only my opinion guys but those ssts near the Dateline in my mind are the crucial factor whether the Eastern states are gripped by drought or can get away with timely rains. Victoria on the other hand will depend more on the IOD over the coming months but does help as well the fact that the ssts near the dateline if they stay Neutral due to the colder PDO.

I know 1 or 2 rain events don't make a season but the fact that next week looks quite wet through Eastern Oz confirms my point on this that the warmer coral sea combined with a favourable IOD (at least Neutral at the moment) will decrease the chances of widespread dry weather developing in the coming months, in the last 3 El Ninos especially 2002 and 2006 we didn't see any decent rain events at all the 2nd part of those Years through inland Eastern and SE OZ.

Thats my take on it

Sounds interesting Johnno
I had to refresh where the dateline is..Embarrassed..
http://upload.wikimedia.org/wikipedia/commons/6/61/International_Date_Line.png

Obviously this is a different region to NINO 3.4 etc
Where does this region you refer to sit in relation to the traditional monitoring ocean areas? co-ordinates? latitude /longitude..

--------
SO
RE: quote from BOM
The Bureau of Meteorology is forecasting a dry season as the region enters an El Nino weather pattern.

The ENSO pattern is from autumn to autumn and the 2012 rainfall pattern appears to be right on target for an EL Nino rainfall pattern
3 months rainfall percentiles for April to June 2012




The map below from
http://www.bom.gov.au/climate/enso/ninocomp.shtml

This what the same period is likely to look like at this stage of a strong El Nino event
Notice we have actually had less rain than is expected for this stage of the cycle ( for a strong El Nino event)

Having said that

I haven't seen the rainfall sequence Autumn to autumn for neutral or weak El Nino events
are they available?

Autumn to autumn evolution

The following table shows the evolution of 3-month rainfall deciles averaged over the 12 El Niño events. Each overlapping 3-month period is shown from autumn (March to May) of the onset year, to autumn of the decay year.

Apologies Ken ,

I definitely know what your talking about with respect to their long term outlook . I just think you don't see forecasts as half as strong as next weeks in any year that is forecast any more than the slightest of Nino's .

As for SW WA , i'm quite aware of whats going on over there , i used to live there in in the mid noughties . And still have friends there that i regularly keep in touch with .

And crikey , my commnets were more to do with the Winter spring as opposed to the entire ENSO year of Autumn to Autumn . Those deciles will be given a shake up if only half of next weeks forecast comes off .... the best of which is hinting at two Nth moisture injections , and what isn't seen yet is the possibilty of a following SW in feed/ blast .

The habit is to spot what looks like a condition, go to the airwaves about it, and wait and see what happens, safe in the knowledge that the public don't know the difference between a condition and an episode. The 'out' is that you call off on it a year later and go with one or the other. That way you'll always be correct. If it remains a condition you call it an El Nino but a fizzer. If it turns out to be an episode you've won the lottery. Along the way everyone gets excited because it's newsworthy and there's been no El Nino-spotting for a couple of years. But it is a lunar cycle and refers to reversing currents which translate to surface winds through the ocean/air interface, which in turn influence pressure zones. The turnaround averages about 4-5 years, the 4 quads of the 18.613-yr nodal cycle. I believe the best El Ninos can be trusted to arrive 1-yr after solar minimum. I am positive there won't be an El Nino this year or next year, but there'll be a lot of talk about it being a certainty, just because we will continue to see drier than average conditions especially in the eastern half, followed by a delayed monsoon season at the top. My prediction is that this time next year there'll be a lot of people denying they uttered anything about any El Nino.

I feel like I'm in that movie " a Fish called Wanda " , with Two Ken's ..............

But yes , thanks for your valued input Ken ( Ring ) .....

I tend to agree with Ken Ring,on this occasion, but because of solar conditions alone, which suggest 1 El Nino from 2014 to to 2017 and 2 El Ninos from 2018 to 2021, and a quite low chance of anything of any El Nino strength till 2014 (see http://www.holtonweather.com/DROUGHTRESEARCHPAPERMay2012PTLJC7.pdf ).
PLus. the Mid Pacific Ocean PDO coolness, as mentioned by several, adding to the low chance of anything having much effect upon Australia El Nino wise that is.

I think government weather blokes are trying to pitch for extra funding, the usual story. To be called an El Niño or La Niña event the measured index has to exceed +0.4°C for El Niño or -0.4°C for La Niña for the mandatory 6 consecutive months. It is nowhere near that at the moment, but at least it has reached a neutral phase on its apparent way to the positive. So it must reach +0.4°C point first, then stay there for 6 months. If the index does leap up over the next 6 months, then by this coming January there is that a suggestion of El Nino, but not before.
But even if it got cracking now, it would be at least a month from now before it hit the +0.4°C level, putting any El Nino off until at least next February. Probably the most we could then expect would be for a neutral period to continue by late August or September of this year, then start to enter some kind of weak El Nino phase by December if anyone is that desperate to still make the call on it, but even then it would only be by about +1°C and nowhere near fully-fledged.
It means that even if the east of Australia was looking at a dry summer, or at least drier than last summer, they still wouldn't be able to call it an El Nino until next autumn, well into 2013, if indeed it went according to this plan. Is that likely? Hardly. The government is always trying to find ways to spook the farmers. If they can threaten them with the El-Nino-drought idea, it makes them more taxable because global warming/climate change/bizarre weather gets floated out again.

No problems Southern Oracle.

As for extra funding, what is it with people and wanting to find a ridiculous conspiracy in everything? It's the same tired old recirculated ridiculous conspiracy line that BoM staff somehow get extra funding for declaring an El Nino. Staff don't get a single extra cent whether an El Nino or La Nina is declared. If that was the case, none of the last few La Nina's would've been declared La Nina's. I believe this thread is about interesting & constructive discussion about ENSO, not a conspiracy thread.