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#1427557 - 06/07/2017 21:54 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Surly Bond Offline
Weatherzone Addict

Registered: 23/08/2003
Posts: 2067
Loc: Manilla, near Tamworth NSW
Funkyseefunkydo says of ENSO: "...you only have to go back to 2011 to see the impact it can have."

That is true at my place as you can see.


My monthly climate anomalies sometimes align with ENSO (as NINO3.4), typically when ENSO has a large amplitude.
They have hardly ever aligned since 2011. That graph ends at December 2014, but there has not been alignment with ENSO since then either.
My Manilla smoothed monthly temperature anomalies swing through three degrees, just as NINO3.4 does.
Peaks and troughs in Manilla temperature come one month earlier than those in ENSO.
Troughs and peaks in Manilla rainfall come two month earlier, and those of dew point come three months earlier.
When I fit longer-cycle trends, I find that Manilla is over a year ahead of ENSO.

I discuss the graph above in this blog post.

I am fairly sure I posted the graph in the 2015 part of this forum thread. That thread, of course is in the archives, where no-one will even try to find it.
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#1427560 - 06/07/2017 22:53 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
adon Offline
Meteorological Motor Mouth

Registered: 19/08/2004
Posts: 5295
Loc: Not tellin!
That's fascinating SB! So you can essentially forecast the ENSO state by your smoothed data? What's the prediction for next year????

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#1427629 - 07/07/2017 18:36 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Surly Bond Offline
Weatherzone Addict

Registered: 23/08/2003
Posts: 2067
Loc: Manilla, near Tamworth NSW
I know you are joking Adon, but I'll explain the situation anyway.

My Manilla climate is in step with ENSO only occasionally, and certainly not now.

When the climate is in step, my data shows that this example of Australian climate leads the climate of the central equatorial Pacific by some months. It seems to me that predicting Australian climate from ENSO is less likely to succeed than predicting ENSO from Australian climate.

There are at least two snags:

1. ENSO's effect comes and goes.

We don't know at what times Australian climate is likely to be in step with ENSO. Others here may know something about this. The only paper I know is by Power et al. 1999.
Their title is quite clear about it:
"Inter-decadal modulation of the impact of ENSO on Australia".

2. Data smoothing causes delay

Monthly ENSO data from NINO3.4 is not very noisy, but still it is usually smoothed by averaging over three months, including the month before and after the named date. Such ENSO values are just one month out of date.

In most single-station climate data, any climate signal is overwhelmed by noise. A pattern will emerge only by applying serious smoothing. Even running means do not work well. On the graph I posted, the data points have been smoothed with a 13-point Gaussian curve. As a result, the latest plotted data point is six months out of date. That means that, in a case where my data leads ENSO by two months, the latest ENSO value that I could predict would be the one four months ago. That is, no prediction at all.

If the Manilla climate should happen to get into step with ENSO again in the near future, I should be able to confirm the fact without much delay.
_________________________
Data are cheap; information is expensive!

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#1427645 - 08/07/2017 02:38 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: Surly Bond]
marakai Offline
Weatherzone Addict

Registered: 05/01/2006
Posts: 1746
Loc: Maryfarms NQ
Originally Posted By: Surly Bond
I know you are joking Adon, but I'll explain the situation anyway.

My Manilla climate is in step with ENSO only occasionally, and certainly not now.

When the climate is in step, my data shows that this example of Australian climate leads the climate of the central equatorial Pacific by some months. It seems to me that predicting Australian climate from ENSO is less likely to succeed than predicting ENSO from Australian climate.

There are at least two snags:

1. ENSO's effect comes and goes.

We don't know at what times Australian climate is likely to be in step with ENSO. Others here may know something about this. The only paper I know is by Power et al. 1999.
Their title is quite clear about it:
"Inter-decadal modulation of the impact of ENSO on Australia".

2. Data smoothing causes delay

Monthly ENSO data from NINO3.4 is not very noisy, but still it is usually smoothed by averaging over three months, including the month before and after the named date. Such ENSO values are just one month out of date.

In most single-station climate data, any climate signal is overwhelmed by noise. A pattern will emerge only by applying serious smoothing. Even running means do not work well. On the graph I posted, the data points have been smoothed with a 13-point Gaussian curve. As a result, the latest plotted data point is six months out of date. That means that, in a case where my data leads ENSO by two months, the latest ENSO value that I could predict would be the one four months ago. That is, no prediction at all.

If the Manilla climate should happen to get into step with ENSO again in the near future, I should be able to confirm the fact without much delay.


Surly, I am in no way Dissing your recording or interpretation of your local weather at all, as it is a case in point for all records across Australia.

But just as people might place you in doubt with your records in general, despite your best efforts and attempts as an individual to record your local climate faithfully.

Do you think they will influence the actual 'Official' records at all for your area ?

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#1427651 - 08/07/2017 09:24 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Surly Bond Offline
Weatherzone Addict

Registered: 23/08/2003
Posts: 2067
Loc: Manilla, near Tamworth NSW
Marakai, there is no issue.
My records could scarcely be distinguished from the official records for Tamworth (and, at 18 years, mine are not much shorter). For rainfall I use Manilla official records, except when the gauge is down.
My analysis is just built on the records, by smoothing and collating. You can't get far without smoothing. Anyone can do it if they try. That includes BoM.
I haven't heard that BoM has tried. They are seriously short of funds, I believe.
_________________________
Data are cheap; information is expensive!

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#1427683 - 09/07/2017 04:38 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Mega Offline
Meteorological Motor Mouth

Registered: 03/02/2003
Posts: 6621
Loc: Maryborough, Wide Bay, QLD
Just relentless trade winds on GFS / EC 9 day now. Hard to see any El-Nino develop at this rate!

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#1427710 - 09/07/2017 17:30 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: Mega]
adon Offline
Meteorological Motor Mouth

Registered: 19/08/2004
Posts: 5295
Loc: Not tellin!
Yep SST anomalies looking more like neutral every update. Not that it will mean much. The IOD was always going to hit hard for most of us. Hopefully now the relentless talk about Elnino can be finally put to bed. It's been obvious for a long time that it wasn't going to happening


Edited by adon (09/07/2017 17:37)

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#1427726 - 09/07/2017 22:57 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: Surly Bond]
Seira Offline
Meteorological Motor Mouth

Registered: 27/08/2003
Posts: 7163
Loc: Adelaide Hills.
Originally Posted By: Surly Bond
To Seira
That is an impressive list of Drivers.

It gives others the opportunity to study them smile . When others are ready they can discuss one or more of them in their own time, be it in a day, a month, or in a year's time...X years' time.


Edited by Seira (09/07/2017 23:02)

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#1427806 - 11/07/2017 10:23 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Mike Hauber Offline
Weatherzone Addict

Registered: 13/07/2007
Posts: 2755
Loc: Buderim
BOM and CPC have nino 3.4 stable over the last 2 months. TAO TRITON data however suggests the area has continued to warm significantly over this period. Not sure why the difference, but perhaps BOM and CPC products are influenced by satellite SST data, and I would trust the measurements by the bouys at the surface over the satellite data. Or are there also other surface based measurements that might conflict with TAO (ships, ARGO). Comparisons of current SSTs and trade winds to 2006 and 2009 at same date show no significant difference in my opinion.

TAO is showing the first period of above average trade winds in the central Pacific for several months now. If this continues the warming trend will die. Most el ninos have short periods such as this, so its too early to write of an el nino yet on this basis. CFS 30 day forecasts have been looking a little more like normal trade winds, although still chopping and changing with some runs suggesting significant westerly anomalies continuing.

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#1427984 - 14/07/2017 08:26 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Mike Hauber Offline
Weatherzone Addict

Registered: 13/07/2007
Posts: 2755
Loc: Buderim
CFS and EC have added June nino 3.4 observations to their charts. Both look to have nino 3.4 at the upper range of their forecast spread, which if it continues would mean weak el nino for EC, and warm neutral for CFS. EC shows a clear continuing warming trend for past obs, but CFS shows that nino 3.4 peaked a couple months ago and is flat. NASA has updated to predict a weak warming trend for the rest of the year.

TAO obs show a switch to weak easterly anomalies in the central to east Pacific, and CFS 30 day forecast suggests this may continue. If so it will be interesting to see what happens. Previous years such as 2009 have continued to develop towards el nino with similar weak easterly anomalies dominating this region. However in those years they had much stronger westerly anomalies in the Kelvin wave generation zone, which have been lacking for much of the year so far. The question is how much of the warming trend in the central Pacific has been caused by weak westerly anomalies, and how much by overall weak tropical activity resulting in reduced cloud and increased solar heating. And how long will the weak easterly anomalies continue.

TAO obs show that a WWB is currently occuring in the far west. It is occurring with a weak tropical low in the SH, but no tropical low/typhoon in the NH which is curious considering the season. Models have it weakening out quickly, but I don't think they had picked it up to start with.

CFS and EC have MJO emerging in the Indian Ocean/Australian region in the next week or two, which is destructive towards el nino development (helps boost the Pacific trades). EC progresses the MJO towards the western Pacific which could mean a WWB, whereas CFS has the MJO collapsing again before it gets to the Pacific.

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#1427986 - 14/07/2017 09:07 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
NotsohopefulPete Offline
Weatherzone Addict

Registered: 24/12/2008
Posts: 1087
Loc: Toowoomba
Thanks for that post, Mike. I actually understood it. Is it too soon to see some sort of pattern that about every 8 weeks the almost permanent low/trough through French Polynesia moves and allows the SOI to rise and falls again when it comes back.


Edited by Hopefull (14/07/2017 09:12)

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#1428000 - 14/07/2017 13:54 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Locke Offline
Weatherzone Addict

Registered: 27/12/2007
Posts: 4361
Loc: Brisbane
Looks like the most recent forecast members for CFS are bordering on La Nina conditions are the moment. (Blue is more recent Red is older)



POAMA looks neutral to me, EC looks to have a very wide spread with perhaps an average falling around the warm neurtral. JMA is dab smack neutral.
_________________________
This post and any other post by Locke is NOT an official forecast & should not be used as such. It's just my opinion & may or may not be backed by sound meteorological data. For official information, refer to Australian Bureau of Meteorology products.

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#1428009 - 14/07/2017 15:27 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Mike Hauber Offline
Weatherzone Addict

Registered: 13/07/2007
Posts: 2755
Loc: Buderim
POAMA suggests something like -0.4 for nino 3.4 for August. August starts in 2 weeks. Do you think such a forecast should be taken seriously?

For the other models, they seem to be looking at a lot of cooling by August to remain on track. For example look at EC with the current obs near the top of the forecast range:



While 30 day CFS forecast suggests weak easterly anomalies I'm not sure this is enough. The last few weeks of this thread feature a number of forecasts of trade wind surges which have resulted in at best a stalling of the warming trend - depending on which data source you believe.

Observations from TAO bouy network. It was the trade wind surge in May that some on this forum declared the death of current warming trend.



Edited by Mike Hauber (14/07/2017 15:34)

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#1428025 - 15/07/2017 07:52 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Funkyseefunkydo Offline
Weather Freak

Registered: 30/04/2007
Posts: 487
Loc: East Lake Macquarie
CFS has even gone further towards LaNina today. Wow.

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#1428155 - 16/07/2017 20:33 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
adon Offline
Meteorological Motor Mouth

Registered: 19/08/2004
Posts: 5295
Loc: Not tellin!
All I know is that I am glad that I would not be trying to plan for a cropping season based on any of these models. While IOD and SAM are clearly bigger drivers for the inland SE of Australia, imagine if you had planned on holding off cropping based on the model predictions back in Jan-March!

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#1428203 - 17/07/2017 14:24 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
RC Offline
Weatherzone Addict

Registered: 29/09/2007
Posts: 2085
Loc: near Rockhampton, Qld
We will be on La Nina watch next. grin

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#1428206 - 17/07/2017 14:41 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: RC]
adon Offline
Meteorological Motor Mouth

Registered: 19/08/2004
Posts: 5295
Loc: Not tellin!
Originally Posted By: RC
We will be on La Nina watch next. grin


Where is the like button!

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#1428207 - 17/07/2017 14:57 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Mega Offline
Meteorological Motor Mouth

Registered: 03/02/2003
Posts: 6621
Loc: Maryborough, Wide Bay, QLD
Strongest burst of trade winds all year, by FAR, coming up over the next few days. It will be interesting to see how 3.4 reacts after being stuck in limbo for the last couple of months or so. As Mike and others did accurately predict, cold pool(s) that were building on the subsurface weakened and failed to make it anywhere near the surface, you'd think if that kept happening then the big dip in CFS's forecast seems unlikely.

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#1428210 - 17/07/2017 15:11 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
RC Offline
Weatherzone Addict

Registered: 29/09/2007
Posts: 2085
Loc: near Rockhampton, Qld
If you look at the sea surface height map, it show a lot of the southern pacific is lower then normal.

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#1428254 - 17/07/2017 22:50 Re: Climate Driver Discussion 2017 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Chris Stumer Offline
Weatherzone Addict

Registered: 28/01/2010
Posts: 1609
Loc: Kingaroy
Perhaps if La Nina does indeed form this year it could be the La Nina that we should of got in 2016 but all the heat from the 2015 El Nino threw everything out of whack.

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