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#1102899 - 06/05/2012 11:38 Re: ENSO Discussion 2012. [Re: NotsohopefulPete]
retired weather man Offline
Meteorological Motor Mouth

Registered: 01/07/2007
Posts: 5161
Loc: Wynnum
I was in Melbourne in 1982, where water rationing was introduced.

However that same year mentioned above - 1983, things changed in a few short months, as inland Qld was swamped in June.

I know this as BoM transferred me from Melbourne to Darwin, and I chose to drive with the family up the inland way as it was the middle of the dry.. Bad move.

The rain started at Charleville, and we barely made it to Tambo ( 150mm in 24 hours - a then record June rain ) then got stuck in Blackall waiting for the Barcoo to drop, then barely made it out of Barcaldine with water half a metre over the road and finally got stuck again at Winton waiting for the water to drop again ( dirt road in those days ), but after Cloncurry it was smooth sailing.

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#1102906 - 06/05/2012 13:45 Re: ENSO Discussion 2012. [Re: retired weather man]
NotsohopefulPete Offline
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Registered: 24/12/2008
Posts: 1405
Loc: Toowoomba
Dear Retired Weather man
It is so great to hear from somebody who remembers that time. It is something that all these younger ones will probably never see. It was such an amazing turn around from record drought to a series of massive rain events starting with a huge monsoonal low in March. I actually think the second event stating with a north west cloud band about Anzac Day and continued for over a week was the biggest and best. I think it is the biggest rain event I have ever seen for the length of time it lasted and the area of the continent it covered and best of all it wasn't destructive flooding. There was a similar set up in April 89 I think but If I remember correctly I did cause some serious flooding. in SE QLD and NE NSW.
Regards

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#1102937 - 06/05/2012 18:21 Re: ENSO Discussion 2012. [Re: NotsohopefulPete]
ColdFront Offline
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Registered: 29/06/2008
Posts: 19046
Loc: The Beach.
....and a very cold snowy winter in the sth east. Macedon ,still charred went from black to white.
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#1102953 - 06/05/2012 20:06 Re: ENSO Discussion 2012. [Re: NotsohopefulPete]
crikey Offline
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Registered: 01/02/2011
Posts: 3184
Loc: Tweed Heads
thanks for all the info 'guys', very informative
found some info on the 1982 el nino

8. 1982 El Niño: the worst there ever was

The 1982-83 El Niño was the strongest and most devastating of the century, perhaps the worst in recorded history. During that period, trade winds not only collapsed-they reversed direction. Its effects were long lasting as well. It caused weather-related disasters on almost every continent. Australia, Africa, and Indonesia suffered droughts, dust storms, and brush fires. Peru was hit with the heaviest rainfall in recorded history-11 feet in areas where 6 inches was the norm. California had very high rainfall and the year was characterized by extensive flooding and landsliding. The event was blamed for nearly 2,000 deaths and more than $13 billion in damage to property and livelihoods. During this period, the thermocline off the South American coast dropped to about 500 feet. On September 24, in just 24 hours, sea-surface temperatures along a coastal village in Peru shot up 7.2 degrees F.

The last diagram shows sea-surface temperature anomalies during the 1982-1983 El Niño.


here is the link to flood summaries in qld for this time period 1980's
http://www.bom.gov.au/hydro/flood/qld/fld_history/floodsum_1980.shtml

1982 - 83

This extensive drought affected nearly all of eastern Australia, and was particularly severe in south eastern Australia. Lowest ever 11 month rainfall occurred over most of Victoria and much of inland New South Wales and central and southern Queensland; and lowest ever 10 month rainfall occurred in much of South Australia and northern Queensland. Total losses were estimated in excess of S3,000 million.
.......
El-Nino is linked to a swing in the mean atmospheric pressure difference across the Pacific Ocean called the Southern Oscillation. Many of the widespread and severe droughts affecting eastern Australia identified above were a direct consequence of a marked swing in the Southern Oscillation.
http://www.abs.gov.au/ausstats/abs@.nsf/Previousproducts/1301.0Feature%20Article151988?opendocument&tabname=Summary&prodno=1301.0&issue=1988&num=&view=

couldn't find the BOM 1982 annual climate statement
does anyone know where the link is to the archives for 1982?









Edited by crikey (06/05/2012 20:06)
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#1102961 - 06/05/2012 20:52 Re: ENSO Discussion 2012. [Re: crikey]
_Johnno_ Offline
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Registered: 08/11/2009
Posts: 1745
I know interms of rainfall the 1997-98 El Nino wasn't as bad for OZ but interms of strength wasn't it just as strong if not stronger than the 82-83 El Nino?
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#1102965 - 06/05/2012 21:17 Re: ENSO Discussion 2012. [Re: _Johnno_]
NotsohopefulPete Offline
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Registered: 24/12/2008
Posts: 1405
Loc: Toowoomba
Once again going just by memory I remember it was said by a climatologist that the high pressure belt occasionally stays in the summer position some winters and thats what happened in the winter of 97 and also the ocean temps around Australia were mostly above normal during the summer of 97-98. Especially the Tasman and southern Coral sea were so much above normal I remember it even made the northern rivers ABC news.Seems these two features helped Australia escape the worst effects of the El nino.Interestingly I can never remember the terms El nino or la nina mentioned in the media before 1982 (doesn't mean it wasn't). But of course being such a dramatic event el ninos suddenly became famous.


Edited by Hopefull (06/05/2012 21:17)

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#1103416 - 09/05/2012 15:39 Re: ENSO Discussion 2012. [Re: NotsohopefulPete]
Locke Offline
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Registered: 27/12/2007
Posts: 4553
Loc: Brisbane
After dipping briefly into negative territory the 30 day SOI is again back in the positive.

TAO/Triton now seems to be showing the subsurface warm pool has weakened significantly although +2 anomalies can now be seen at the surface in the East.

Perhaps we are looking at neutral conditions through to summer.
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#1103418 - 09/05/2012 16:04 Re: ENSO Discussion 2012. [Re: Locke]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2984
Loc: Lane Cove, Sydney, NSW
I'm not seeing any significant weakening, if anything the core of the warm pool is shifting east. Odds are more in favour of weak Nino through summer, IMO.

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/wkxzteq.shtml
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#1103452 - 09/05/2012 20:34 Re: ENSO Discussion 2012. [Re: CoastalStorm22]
Locke Offline
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Registered: 27/12/2007
Posts: 4553
Loc: Brisbane
Earlier in the year the Tao/Triton data was showing -4 to -5 anomalies in the West. It is now showing only -2 to -3. Clearly the CFS data is showing something different.




Edited by Locke (09/05/2012 20:35)
Edit Reason: spelling
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#1103570 - 10/05/2012 15:33 Re: ENSO Discussion 2012. [Re: _Johnno_]
crikey Offline
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Registered: 01/02/2011
Posts: 3184
Loc: Tweed Heads
Re johnno's question
If the SOI ( southertn oscilllation index)is a measure of the strength of an El nino then this graph indicates the 1982 El Nino was the strongest since 1880 and 1982 stronger than 1997, with a 6 month june to nov average SOI of -22.6


http://www.bom.gov.au/climate/enso/ninocomp.shtml

However maybe SST anomaly is a better measure of strength or maybe SOI and SST anomaly combined??

1982 rainfall deciles for the corresponding time period
http://www.bom.gov.au/climate/enso/d6a1982.shtml

and 1997 rainfall deciles for the 1997 el nino event
http://www.bom.gov.au/climate/enso/d6a1997.shtml

Noticed they ( BOM) haven't added the el nino events since 1997
what a shame!
surely there has been a significant El Nino event since 1997?
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#1103576 - 10/05/2012 15:53 Re: ENSO Discussion 2012. [Re: crikey]
Arnost Offline
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Registered: 10/02/2007
Posts: 3909
WRT to the 1982/83 El Nino, I'd be careful making attributions one way or another as the tropical atmosphere was strongly influenced by a volcanic eruption that pumped significant amounts of SO2 into the atmospehere...
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#1103581 - 10/05/2012 16:15 Re: ENSO Discussion 2012. [Re: Arnost]
Ken Kato Offline
Meteorological Motor Mouth

Registered: 05/03/2012
Posts: 6090
Crikey: Different organisations have slightly different ways or benchmarks for measuring ENSO phases. SST anomalies in the NINO regions are usually considered a primary indicator of these phases but other indicators like the SOI, outgoing longwave radiation anomalies/cloudiness, trade winds, etc are also monitored here. NOAA (US) uses SST anomalies as their benchmark.

It's important to remember that although the SOI often reflects a particular ENSO phase, it's an atmospheric indicator. Sometimes the atmosphere and ocean don't couple well (i.e. feedback between the two) resulting in for example, SST patterns typical of an El Nino but the SOI doesn't reflect it. This happened in the El Nino of 2009 when there were warm SST anomalies in the central Pacific, typical of a Modoki El-Nino but the SOI didn't truly reflect it during the early stages. So even though the oceans may reflect an El Nino pattern, the atmosphere sometimes doesn't or lags significantly behind the response.

Re SOI graphs, below is a Bureau one from 2000 to 2007. You can find earlier and later ones here: http://www.bom.gov.au/climate/current/soi2.shtml


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#1103714 - 11/05/2012 12:08 Re: ENSO Discussion 2012. [Re: Ken Kato]
_Johnno_ Offline
Weatherzone Addict

Registered: 08/11/2009
Posts: 1745
May run of POAMA has increased the chance of El Nino by late Spring into Summer but at the same time its increased its chances from the April run of a Negative IOD for Winter

http://www.bom.gov.au/climate/poama2.4/poama.shtml
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#1103721 - 11/05/2012 12:26 Re: ENSO Discussion 2012. [Re: _Johnno_]
Chris Stumer Offline
Weatherzone Addict

Registered: 28/01/2010
Posts: 1883
Loc: Kingaroy
what would the effects be on our weather if we do get an El Nino with a negative IOD?

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#1103728 - 11/05/2012 13:04 Re: ENSO Discussion 2012. [Re: Chris Stumer]
ROM Offline
Meteorological Motor Mouth

Registered: 29/01/2007
Posts: 6628
Chris Stumer, the info you seek can possibly be found in the following;

Caroline Ummenhofer's very good The Role of the Indian Ocean for SEA droughts
The cross related IOD / Enso phase years are in the last panel.

Enso / IOD years by the original authors Peter McIntosh [ whose father use to be our bank manager here in Horsham ] Mike Pook who regularly turns up at the Birchip Expo in July each year and L. Pigot.

Federation and Meteorology which has one hundred [small ] maps of annual Australian rainfall dating from 1900 to 1999.

This one along with the Enso / IOD panel are probably well worth saving to use as an indicator of the possibilities when we get a similar ocean set up as to what has occurred previously.

Edit; arrows at the bottom of the page take one to the previous / next article in the series which covers a whole range of Australian climate and weather related factors.

Hope this helps.


Edited by ROM (11/05/2012 13:14)

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#1103736 - 11/05/2012 14:23 Re: ENSO Discussion 2012. [Re: ROM]
Surly Bond Offline
Weatherzone Addict

Registered: 23/08/2003
Posts: 2193
Loc: Manilla, near Tamworth NSW
Cumulative values of the Southern Oscillation Index

This graph is a log of cumulative values of the monthly Southern Oscillation Index for the last 135 years. High values of the SOI (contrary to NINO3.4) relate to deluges in Australia and low values relate to droughts.
This is the CUSUM technique, invented in 1954 by E.S.Page.

Read the slopes on the graph.

I have identified the major El Nino and La Nina events from the graph posted by crikey (6 posts up). La Ninas have extreme upward slopes and El Ninos exteme downward slopes.
The main feature of the graph, which is obscure in graphs that do not use CUSUM, is that La Ninas dominated the 60-year period from 1917 to 1976, and El Ninos dominated the 25-year period from 1976 to 2000. The tendency to El Ninos in the second period was greater than the tendency to La Ninas in the first period by a factor of more than two.
It is not clear whether the climate after 2000 is neutral for the SOI, as it was for the 40 years before 1917, or whether El Ninos or La Ninas will again dominate.
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#1103739 - 11/05/2012 14:50 Re: ENSO Discussion 2012. [Re: ROM]
crikey Offline
Weatherzone Addict

Registered: 01/02/2011
Posts: 3184
Loc: Tweed Heads
Thanks Ken.K for your response , explanations and link .
and your time and patience , helping those who are learning.
Often catch your posts for the public to read and are always very informative, interesting and much appreciated

and to others as well..thanks


Thanks ARNOST on the tip re the Chichon eruption for 6th April 1982 ,during the time period of what is described as the strongest El Nino by some sources

Thanks ROM as well , looks interesting when l get time to read

John Dalys has written an article on the relationship between the SOI, global temps and ENSO
http://www.john-daly.com/soi-temp.htm

According to DALY's graph. If chichon hadn't erupted the global temps would have gone MUCH higher in 1982

He also made comparisons between the 1982 and 1997 el Nino events
quote..
This leaves the interesting question. Why did the 1997-98 El Niño result in such a large surge in global temperature when the even stronger 1982-83 El Niño only resulted in a small rise in temperature? Was this a greenhouse warming finally taking hold?

The grey shaded areas of the chart give the answer. The El Chichon eruption of 6th April 1982 was powerful enough to eject aerosols and dust particles into the stratosphere, resulting in greater scattering and reflection of incoming sunlight, thus dampening the warming effect of El Niño. Had El Chichon not intervened, global temperature would have been free to soar to the values we have seen in 1998 where no volcanic activity was present to inhibit the warming effect. Even so, the 1982-83 El Niño did manage a small warming in spite of El Chichon’s countervailing cooling effect.

This volcanic cooling effect is revealed very clearly by the Mount Pinatubo eruption, considered to be the biggest this century, with a cooling effect lasting even longer than El Chichon, and with a much more dramatic effect on global temperature, cooling the earth in spite of mostly El Niño conditions during the early 1990s. It will be noticed that the only times in the 20 years when global temperature did not show the full 9-month delayed response was during those periods shown in grey shade when volcanic activity intervened to produce a modified outcome. In 1982-83, we get the predicted warming response, but at a much weakened level, while the Pinatubo eruption effectively cancelled (and even reversed) the effect of the Southern Oscillation
----------------
Wonder what role the chichon eruption had on creating the abrupt change from dry to wet in 1983 that RWM described?

Daly seems to infer that the SOI index ( Barom pressure change between darwin and tahiti) acts like a global temp thermostat( or one of them).Atmospheric pressure change first followed by change in global temp
with a 6 to 9 month time lag.and NINO effect in that sequence somewhere
Is there a sequence of events in indicators?

so do SST's alter the atmospheric pressure difference in darwin or tahiti or does Barom pressure and wind regimes alter SST temps.?
The egg before the chicken argument?
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#1103749 - 11/05/2012 15:10 Re: ENSO Discussion 2012. [Re: crikey]
crikey Offline
Weatherzone Addict

Registered: 01/02/2011
Posts: 3184
Loc: Tweed Heads
Excellent work SURLYBOND. What a find! Look forward to members responses.
The mind boggles!!
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#1103755 - 11/05/2012 15:28 Re: ENSO Discussion 2012. [Re: crikey]
Vinnie Offline
Meteorological Motor Mouth

Registered: 17/05/2006
Posts: 6821
Loc: Mulambin , Yeppoon Central Qld
So in an El Nino would Yeppoon see more NW, W or SW winds in summer and less SE,E and NE winds ?
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#1103775 - 11/05/2012 17:21 Re: ENSO Discussion 2012. [Re: Vinnie]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6050
Loc: Eastern A/Hills SA
Good find SB! I will use it on some of my data and see what comes up! Thanks!

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