Sst's And Sea Ice - Trends

[West is Best]

I think its the classic Bartlett high type set-up,

<{POST_SNAPBACK}>

Yes ... I quite agree. Got that look to it hasn't it? But there's still a fair time to go until this becomes critical. I reckon if these anomalies remain this high in 4-6 weeks time then there's real problems for the cold scenario - at least in terms of a big freeze type winter.

By the way - just read back and saw Wayneywoo's question. Actually, the GIN corridor is definitely less +ve at the moment than last year, so that is something good. But the eastern seaboard and mid-Atlantic are above. It's early days still ...

Edited September 9, 2005 by West is Best

[The Enforcer]

Assuming the anomalies stayed broadly as they are now, in the event of a northerly incursion, would the slight negative anomalies directly to the north off the UK (as opposed to last winter's massive positive anomalies) result in much less warming of the arctic air and a more potent northerly, although still brief?

[AtlanticFlamethrower]

Close up of the sst anomaly chart.

Note: North Sea SSTs currently running 1+/ 2+

[reef]

Close up of the sst anomaly chart.

http://img368.imageshack.us/img368/5241/gi...pt0720058sq.png

Note: North Sea SSTs currently running 1+/ 2+

<{POST_SNAPBACK}>

That is one good thing at least. With SSTs to our north around average, any northerlies should be as cold as they used to be (assuming the air source is too). The main problem I fear is the northerly tracking jet, which allows less time for the cold air to penetrate south before the high pressure topples and introduces milder air from the north-west. Either that or we stay in the mild sector or get battered by secondary low pressure systems.

[The Enforcer]

Either that or we stay in the mild sector or get battered by secondary low pressure systems.

<{POST_SNAPBACK}>

That horrible 'daisy-chain effect' with Low after Low after Low crossing the Atlantic and connected by fronts that seem to permanently straddle the UK. Yuk.

Edited September 9, 2005 by The Enforcer

[West is Best]

That horrible 'daisy-chain effect' with Low after Low after Low crossing the Atlantic and connected by fronts that seem to permanently straddle the UK. Yuk.

<{POST_SNAPBACK}>

The way those SSTs have pushed +ve over the last 2 weeks even the parts just above average to the north may push further ahead. Still plenty of time for change though.

[The Enforcer]

I'm not sure that they are on the up overall. There seems to me to be more blue about and certainly less yellow:

http://weather.unisys.com/archive/sst/sst_anom-050821.gif

http://weather.unisys.com/surface/sst_anom.gif

Edited September 9, 2005 by The Enforcer

[The Enforcer]

Using Unisys data, I have put together a comparison of actual SSTs for the first week of September for each of the past 6 years:

Taking Faroe Islands as an example, the dataset reads as follows:

2000 - 11C

2001 - 11C

2002 - 10.5C

2003 - 12.5C

2004 - 12C

2005 - 10C

Edited September 10, 2005 by The Enforcer

[West is Best]

Using Unisys data, I have put together a comparison of actual SSTs for the first week of September for each of the past 6 years:

Taking Faroe Islands as an example, the dataset reads as follows:

2000 - 11C

2001 - 11C

2002 - 10.5C

2003 - 12.5C

2004 - 12C

2005 - 10C

<{POST_SNAPBACK}>

I'm very sceptical about the accuracy of this I'm afraid. Have you used proper feeds from buoys over this period? The SST maps are pretty notorious for inaccuracy, but a cursory glance at the charts suggests SSTs for the northern hemisphere are extremely high this year. What might be interesting is for you to do a comparison of the eastern seaboard, and GIN corridor. Now why, I wonder, would you have plumped for the Faroe Islands as your example ...?

Edited September 10, 2005 by West is Best

[The Enforcer]

Now why, I wonder, would you have plumped for the Faroe Islands as your example ...? 

<{POST_SNAPBACK}>

Because they are directly north of the UK and the SSTs in that area will modify any direct arctic incursions that occur.

[SMU]

I'm very sceptical about the accuracy of this I'm afraid. Have you used proper feeds from buoys over this period? The SST maps are pretty notorious for inaccuracy, but a cursory glance at the charts suggests SSTs for the northern hemisphere are extremely high this year. What might be interesting is for you to do a comparison of the eastern seaboard, and GIN corridor. Now why, I wonder, would you have plumped for the Faroe Islands as your example ...? 

<{POST_SNAPBACK}>

Good afternoon All-

I dont wish to put a dampner on this thread that is moving along nice- however-

I think it would be a good idea to put things into Perspective-

I remember ( In a heated arguement) my Mother told me

" The world doesnt revolve around you!! "

and this can be said of the GIN corridoor and SST's to the North of us-

In terms of Anomalies its good to see -VE ones to the north as they have some a(although minimalish) modifications on boundry layer temps in Northerly incursions-

However-

What no-one on here has is enough backgorund information on SST's to provide an account on how they will effect this winter based on the fact that the whole globe is effected by lower Scale regional Anomlies-

The 2 biggest 'hitters' probably in terms of global perspective is the ENSO & PDO-

both having large scale effects on global patterns-

Now this year the ENSO is looking fairly neutral suggesting that is will play little or no major part in proceedings-

However the PDO with lesser background information hasnt really got a seasonal forecast because there hasnt been a full proof way of forecasting the changes of it yet-

The correlation so far though in terms of effecting the uk through teleconnections is-( with limited knowledge) ive clipped a bit from my Ode-

The PDO is described as being in one of two phases: a warm phase and a cool phase. Alternately, the PDO can be described by its index value: warm (cool) phase conditions correspond to positive (negative) index values

The AO/NAO was mostly negative during the cool phase of the PDO and mostly positive during the warm phase. The change to a negative PDO in the middle 90s coincided with the change towards negative of the AO and NAO. This would suggest a predisposition towards a negative AO and NAO any winter preceeded by a negative flip of the PDO.

With SO many anomalies effecting the Northern hemisphere this year its a lttle on thin side to make any forecasts JUST based on whats happening in one staright of water-

I do accept the effects that the GIN corridoor has on Low pressure systems- However there are larger forces at work that mean when the time comes to winter these anomalies WONT be a factor in determining the Local of the jet stream.....

regards

Steve

Edited September 10, 2005 by Steve Murr

[beng]

Http://www.osdpd.noaa.gov/PSB/EPS/SST/data...ht.9.9.2005.gif

The Sea to our NE continues to cool faster than normal - cold winter fans should hope this continues. While it doesn't guarantee anything, it ought to aid blocking in the region and promote the chances of Easterly outbreaks later in the winter. Additionally as others have noted Northerly winds may be more potent.

:o

[West is Best]

The Sea to our NE continues to cool faster than normal -  :o

<{POST_SNAPBACK}>

No it doesn't. The trend over the past 4 weeks has been for northern hemisphere ocean +ve anomalies to spread. The only sign of hope that I can see for cold lovers is that the extremes are not at the moment quite as acute as last year in certain key areas. Unfortunately the eastern seaboard and mid-Atlantic are well above average, and this is a very poor sign for the winter. The GIN corridor, all important, is slightly less above average than last year.

[beng]

No it doesn't. The trend over the past 4 weeks has been for northern hemisphere ocean +ve anomalies to spread. The only sign of hope that I can see for cold lovers is that the extremes are not at the moment quite as acute as last year in certain key areas. Unfortunately the eastern seaboard and mid-Atlantic are well above average, and this is a very poor sign for the winter. The GIN corridor, all important, is slightly less above average than last year.

<{POST_SNAPBACK}>

What data are you using?

compare the chart I posted with this one from a few weeks ago

http://www.osdpd.noaa.gov/PSB/EPS/SST/data...t.8.27.2005.gif

[West is Best]

What data are you using?

compare the chart I posted with this one from a few weeks ago

http://www.osdpd.noaa.gov/PSB/EPS/SST/data...t.8.27.2005.gif

<{POST_SNAPBACK}>

Well of course the sea is cooling - we've gone from August to September! I'm using the anomaly charts and the +ve anomalies have grown since 4 weeks ago.

I find the good 'ol net-weather SST anomaly chart to be fine - certainly a little more distinct that the one you are using which looks like it's taken from a satellite hovering somewhere over Tierra del Fuego!

[SNOW-MAN2006]

well (using the charts from n-w) to me it looks like the seas to the south of the uk vary alot from the seas to the north! just above scotland is 12 celcius in the north sea and down in the channel it 17.5!!! 5.5 diffrence over around 500 miles so with a little more old weather these seas will cool down alot and the anomolies showing the atlantic down on average by spain.

[beng]

Well of course the sea is cooling - we've gone from August to September! I'm using the anomaly charts and the +ve anomalies have grown since 4 weeks ago.

I find the good 'ol net-weather SST anomaly chart to be fine - certainly a little more distinct that the one you are using which looks like it's taken from a satellite hovering somewhere over Tierra del Fuego!

<{POST_SNAPBACK}>

The charts on Net Weather are from unisys

http://weather.unisys.com/surface/sst_anom.html

And 3 weeks ago

http://weather.unisys.com/archive/sst/sst_anom-050821.gif

These anomoly maps also show that temps to the North are now dipping below normal. Look at Iceland. There is an area of above normal to the far North East - north of Russia - but in terms of surface area, this will be very small. At any rate these maps vary a lot - so you need to look at several different sources to get the bigger picture as to what's happening.

Perhaps we should just agree to disagree on this one.

[AtlanticFlamethrower]

As you might expect deep water is colder than hot water at the surface getting heat from the sun. When hurricanes churn the waters with their 100mph+ winds cold waters below are stirred to the surface. Hurricanes gain strength from heat of water and need to keep moving to get stronger.

Here are charts showing SST anomalies in the Gulf of Mexico before and after Hurricane Katrina, a Catagory 5 Hurricane.

Presumably in the days after the storm past a SST positive anomaly (+ve?) became a negative one.

The same thing happens during strong storms over polar waters. Negative SST anomalies can be caused by cold water getting churned up from below by a big storm.

Here's the GFS for the day before this SST anomaly chart (the first beng posted showing warm anomaly above Iceland. Note the absence of a big storm. Here's the GFS for a few days before the most recent SST anomaly chart (the second beng posted showing cold anomally above Iceland). Little more activity might partly explain cold anomaly.

Too much might be read into SST anomalies as they can go up and down due to the presence above it of a single storm, which may be caused by a whole host of other factors, irrespective of a cold or warming trend. I'm not saying SST are not unimportant - if you want cold winter you won't care how the anomaly came about. Great, it's cold! However if you're looking for signs of cold winter i think steve murr indicated our prayers for lower STTs should not be at expense of wanting a more southerly Jet Stream than last year.

[SMU]

Too much might be read into SST anomalies as they can go up and down due to the presence above it of a single storm, which may be caused by a whole host of other factors, irrespective of a cold or warming trend. I'm not saying SST are not unimportant - if you want cold winter you won't care how the anomaly came about. Great, it's cold! However if you're looking for signs of cold winter i think steve murr indicated our prayers for lower STTs should not be at expense of wanting a more southerly Jet Stream than last year.

<{POST_SNAPBACK}>

Good post there AFT-

Based on that premise the north atlantic should get a good stir this week....

S

[AtlanticFlamethrower]

Indeed, you'd expect the recent flaring up of the north atlantic to continue to cool.

http://weather.unisys.com/archive/sst/sst_anom_loop.gif

However... with S/N movement of Maria I'm not sure they'll be a big cooling effect in the waters south of Iceland, for this reason - the storm might drag warm water with it. It's like when you add hot water to a cold bath and then drag your hand the length of it. Any cooling we might see in the North Atlantic next week (from colder waters being churned up by Maria) maybe somewhat offset from warm waters bought along from the gulf stream. It might be interesting to see the next image in the loop.

[AtlanticFlamethrower]

Accidental double post. First one timed out but actually was sent through.

Edited September 11, 2005 by AtlanticFlamethrower

[The Enforcer]

I've put together a data set for the first run on the archive charts of each year since 2001:

It can be seen that there are highly positive anomalies in the area between Iceland and Greenland (which I believe to be the GIN sea) every year apart from 2001. Late Dec 2000 saw the last polar low event to hit the UK, which brought widespread snowfall over inland UK (apart from Abingdon, of course). It appears highly likely that there is a connection between the lower SSTs in that area and the sustained northerly that was experienced, yet to be repeated.

Here's the latest situation:

http://weather.unisys.com/archive/sst/sst_anom-050918.gif

compared with this time last year:

http://weather.unisys.com/archive/sst/sst_anom-040919.gif

The high positives were already in place last year, can this year's average/slight negative area extend eastwards and stop them from forming this year?

[summer blizzard]

In my opinion, the current anomnolies most closely match January 2002.

[sjpdevine2000@yahoo.co.uk]

Just wondered if anyone out there has noticed the cold pool of surface sea temperatures between Iceland and Norway to the north of the UK?

While there is a large area of warm ocean nearer the eastern US seaboard, we could be in for some interesting weather in the coming months if any systems come in from the NNW / Northerly directions!

http://weather.unisys.com/surface/sst_anom.html

[Anti-Mild]

Just wondered if anyone out there has noticed the cold pool of surface sea temperatures between Iceland and Norway to the north of the UK?

While there is a large area of warm ocean nearer the eastern US seaboard, we could be in for some interesting weather in the coming months if any systems come in from the NNW / Northerly directions!

http://weather.unisys.com/surface/sst_anom.html

<{POST_SNAPBACK}>

I had noticed the cold pool also. What has to be considered is that the SST's in January will most likely not resemble the ones we have currently.

However, am I right in surmising that if the cold pool remains between Iceland and Norway, that it would inhibit the formation of LP's in that area and consequently bring about the possibility of a strong SH?