EL NI O: Northern Hemisphere Winter 2009-2010

Big Tone

Thought y'all might be intersted in this..

Synopsis: El Niño conditions will continue to develop and are expected to last through the Northern Hemisphere Winter 2009-2010.

During June 2009, conditions across the equatorial Pacific Ocean transitioned from ENSO-neutral to El Niño conditions.


What will be the consequences for us? Predictions anyone? Wetter, milder but stormy winter?

Redsunset

yep being watching this myself.could get very interesting.




currently sea surface temps are half to 1 degree above.

this might not seem much but our El Nino (spanish for little infant) has awoken from its sleep.

temps in the 97 event reached 5 degrees above and as you know caused all sorts of mayhem because all that extra hot air over a vast area has to condense and so begins the start of all the precip overs certain areas.

then of course theres the other side of the coin.

other parts of the world become hot and dry with drought.


this website will tells all you need to know about this subject
http://www.pmel.noaa.gov/tao/elnino/nino-home.html

Redsunset

For those interested in current and past global sea temps.
stuck this in here because closest to thread topic.



Global Oceanic Climate Update for August 2009
Dr. Roy Spencer September 1st, 2009

Redsunset

[FONT=verdana,arial]Synopsis: El Niño is expected to strengthen and last through the Northern Hemisphere Winter 2009-2010. [/FONT]
[FONT=verdana,arial]A weak El Niño was present during July 2009, as monthly sea surface temperatures (SST) departures ranged from +0.5oC to +1.5oC across the equatorial Pacific Ocean, with the largest anomalies in the eastern half of the basin (Fig. 1). Consistent with this warmth, all of the Niño-region SST indices were between +0.6oC to +1.0oC throughout the month (Fig. 2). Subsurface oceanic heat content (average temperatures in the upper 300m of the ocean, Fig. 3) anomalies continued to reflect a deep layer of anomalous warmth between the ocean surface and thermocline (Fig. 4). Also, convection was suppressed over Indonesia and enhanced across the western Pacific and near the International Date Line. In addition, developing El Niño’s often feature westerly wind bursts over the western equatorial Pacific, such as the one which occurred at the end of July (Fig. 5). These oceanic and atmospheric anomalies reflect El Niño.[/FONT]

[FONT=verdana,arial]A majority of the model forecasts for the Niño-3.4 SST index (Fig. 6) suggest El Niño will continue to strengthen. While there is disagreement on the eventual strength of El Niño, nearly all of the dynamical models predict a moderate-to-strong El Niño during the Northern Hemisphere Winter 2009-10. A strengthening El Niño during the next few months is also suggested by the recent westerly wind event in the western equatorial Pacific, which can lead to additional anomalous warmth across the central and east-central equatorial Pacific during the next two months. Therefore, current conditions and model forecasts favor the continued development of a weak-to-moderate strength El Niño into the Northern Hemisphere Fall 2009, with the likelihood of at least a moderate strength El Niño (3-month Niño-3.4 SST index of +1.0oC or greater) during the Northern Hemisphere Winter 2009-10.[/FONT]

[FONT=verdana,arial]Expected El Niño impacts during August-October 2009 include enhanced precipitation over the central and west-central Pacific Ocean and the continuation of drier than average conditions over Indonesia. Temperature and precipitation impacts over the United States are typically weak during the Northern Hemisphere Summer and early Fall, and generally strengthen during the late Fall and Winter. El Niño can help to suppress Atlantic hurricane activity by increasing the vertical wind shear over the Caribbean Sea and tropical Atlantic Ocean (see the Aug. 6th update of the NOAA Atlantic Seasonal Hurricane Outlook).[/FONT]

[FONT=verdana,arial,serif]This discussion is a consolidated effort of the National Oceanic and Atmospheric Administration (NOAA), NOAA’s National Weather Service, and their funded institutions. Oceanic and atmospheric conditions are updated weekly on the Climate Prediction Center web site (El Niño/La Niña Current Conditions and Expert Discussions). Forecasts for the evolution of El Niño/La Niña are updated monthly in the Forecast Forum section of CPC's Climate Diagnostics Bulletin. The next ENSO Diagnostics Discussion is scheduled for 10 September 2009.[/FONT]

Redsunset

Redsunset

A study of atmospheric weather conditions (Fraedrich, 1994) found that during the winter (December, January, February) of an El Niño year there is an increased number of cyclonic weather systems over Europe – that is to say that the meteorological map features more low pressure systems, which are accompanied by their usual sort of weather.

This results in colder weather over central and northern Europe, and increased winter precipitation in a band that runs from the British Isles to the Black Sea. A study by Wilby (1993) is consistent with these results, showing that, particularly in the February of an El Niño year, significantly more rain falls, compared to the long-term mean. This is not, however, true for every El Niño event.

Conversely, this study concluded that west and south-west Europe sees less rain during La Niña events, as fewer cyclonic systems pass over compared to the long-term average. Moreover, the position of the European end of the North Atlantic storm track can be affected by the atmospheric pressure anomalies associated with ENSO events. In the case of an El Niño, the North Atlantic lows follow a more southerly route, whereas they follow a more northerly one during a La Niña event.


Van Oldenborgh et al. (1999) describe how El Niño events can have an influence on Europe during the spring months (March, April, May). They found a zone of significantly increased rainfall extending from the British Isles as far as eastern Europe. In the case of the strong El Niño of 1997/8 this increased rainfall was also observed in other areas.

The mid-latitudes feature a climate that is naturally highly variable, so the influence of El Niño on Europe can only be proven through observations over a very long period of time. Such data sets are only available from a few stations, so the connection between the tropics and mid-latitudes is increasingly investigated through the use of climate models.

A study by May (1995) showed that El Niño events can change the pattern of the air flow over the Atlantic-European region, although these changes are much smaller than those seen for the north Pacific sector. Different models, however, show different pattern changes when simulating El Niño events. It is also not yet clear what the relative importance of tropical and extra-tropical sea surface temperatures is when considering the circulation of the mid-latitudes, and to what extent their influence overlaps that of El Niño.

Zzippy

With more low pressure systems heading to Europe and following a more southerly track, does this mean it could be a bumper snowfall year for ski resorts in the Alps?


/heads off to look at skiing brochures....

Redsunset

I sure hope so,was looking at the ski brochures myself only yesterday.i think they will get a good dumping regardless

Redsunset

The positive NAO relates to more zonal flow with warmer Atlantic air into Europe and Pacific air into North America. The negative NAO leads to a more meridional pattern with cold air in Siberia often making its way west to western Europe and Cold arctic air over North America trapped over the eastern and central parts of the continent.


big shout by me for the neg NAO for winter.

Redsunset

Redsunset

[FONT=verdana,arial]One of the most prominent teleconnection patterns in all seasons is the North Atlantic Oscillation (NAO) (Barnston and Livezey 1987). The NOA combines parts of the East-Atlantic and West Atlantic patterns originally identified by Wallace and Gutzler (1981) for the winter season. The NAO consists of a north-south dipole of anomalies, with one center located over Greenland and the other center of opposite sign spanning the central latitudes of the North Atlantic between 35°N and 40°N. [/FONT]

[FONT=verdana,arial]The positive phase of the NAO reflects below-normal heights and pressure across the high latitudes of the North Atlantic and above-normal heights and pressure over the central North Atlantic, the eastern United States and western Europe. The negative phase reflects an opposite pattern of height and pressure anomalies over these regions. Both phases of the NAO are associated with basin-wide changes in the intensity and location of the North Atlantic jet stream and storm track, and in large-scale modulations of the normal patterns of zonal and meridional heat and moisture transport (Hurrell 1995), which in turn results in changes in temperature and precipitation patterns often extending from eastern North America to western and central Europe (Walker and Bliss 1932, van Loon and Rogers 1978, Rogers and van Loon 1979). [/FONT]

[FONT=verdana,arial]Strong positive phases of the NAO tend to be associated with above-averagel temperatures in the eastern United States and across northern Europe and below-average temperatures in Greenland and oftentimes across southern Europe and the Middle East. They are also associated with above-average precipitation over northern Europe and Scandinavia in winter, and below-average precipitation over southern and central Europe. Opposite patterns of temperature and precipitation anomalies are typically observed during strong negative phases of the NAO. During particularly prolonged periods dominated by one particular phase of the NAO, anomalous height and temperature patterns are also often seen extending well into central Russia and north-central Siberia. [/FONT]

[FONT=verdana,arial]The NAO exhibits considerable interseasonal and interannual variability, and prolonged periods (several months) of both positive and negative phases of the pattern are common. The wintertime NAO also exhibits significant multi-decadal variability (Hurrell 1995, Chelliah and Bell 2005). For example, the negative phase of the NAO dominated the circulation from the mid-1950's through the 1978/79 winter. During this approximately 24-year interval, there were four prominent periods of at least three years each in which the negative phase was dominant and the positive phase was notably absent. In fact, during the entire period the positive phase was observed in the seasonal mean only three times, and it never appeared in two consecutive years. [/FONT]

[FONT=verdana,arial]An abrupt transition to recurring positive phases of the NAO then occurred during the 1979/80 winter, with the atmosphere remaining locked into this mode through the 1994/95 winter season. During this 15-year interval, a substantial negative phase of the pattern appeared only twice, in the winters of 1984/85 and 1985/ 86. However, November 1995 - February 1996 (NDJF 95/96) was characterized by a return to the strong negative phase of the NAO. Halpert and Bell (1997; their section 3.3) recently documented the conditions accompanying this transition to the negative phase of the NAO.[/FONT]

Brute75

I have been living in Stockholm for 3 years now and have only seen mild winters with little snow. I have been looking forward to much colder temps and more permanent snow etc. Does the possibility of a light to moderate El nino combined with the slight negative NAO mean a good cold winter is finely on the way to my part of the world.

Kippure

http://www.accuweather.com/video-on-demand.asp?video=34766737001&title=Ocean Temperature Discussion


After hearing this, Changing data to suit certain agenda,s.

See for yourself.

Redsunset

great vid kippure,and looks like that extra cold sst off to our west is still there. didn't know that fred was still lurking and def could be one to watch

Kippure

redsunset wrote: »

great vid kippure,and looks like that extra cold sst off to our west is still there. didn't know that fred was still lurking and def could be one to watch

Without getting himself in to much trouble he does point out the facts. Im working on A small pattern matching project at moment between ocean tempetures and air pressure.

I started a thread on IWN, i hope to have the results soon.

It makes interesting reading.

It relates to cold pooling near our shores and wheather we get a cold or cool winter.

yansnow

just watched a vid from accu and i think a snowy christmas this year.http://www.accuweather.com/video-on-demand.asp?video=40431534001&channel=VBLOG_BASTARDI&title=Euro%20Winter%20Idea,%20More%20on%20Arctic%20Ice%20and%20a%20Look%20at%20Fred

Redsunset

early indications for winter 2009/2010 from uk met office released


Signals for precipitation slightly favour near or above average rainfall over much of northern Europe, including the UK.
What do we mean by average rainfall?

We base our average rainfall on measurements over the whole season for the years 1971-2000. The UK average for December to February is 332 mm.












Temperature

Preliminary indications continue to suggest that winter temperatures are likely to be near or above average over much of Europe including the UK. Winter 2009/10 is likely to be milder than last year for the UK, but there is still a 1 in 7 chance of a cold winter.
What do we mean by average temperature?

As you would expect, temperatures can vary quite widely over the winter. So we take an average for the whole season and measure against that. The UK average for December to February from 1971-2000 is 3.7 °C

Redsunset

joe bastardi is at it again

Interesting winter lurking for Europe.. biased cold in the east and a battle in the west!
My take is a cold winter from Germany east in Europe and a battle winding up near normal farther west, but with some big ticket cold air masses that come back west from the cold pole

read it all http://www.accuweather.com/ukie/bastardi-europe-blog.asp

patneve

what is sure is that it'll start getting quite chilly from Sat onwards:cool:

Kippure

patneve wrote: »

what is sure is that it'll start getting quite chilly from Sat onwards:cool:

http://www.accuweather.com/video-on-demand.asp?video=34766737001&title

Heres his video blog

patneve

Kippure wrote: »

http://www.accuweather.com/video-on-demand.asp?video=34766737001&title

Heres his video blog

very interesting stuff. However, I have 0% trust of long term forecasting. I hope he's right anyway:)

Kippure

patneve wrote: »

very interesting stuff. However, I have 0% trust of long term forecasting. I hope he's right anyway:)

He,s right about one thing. BAck in 2003 atlantic waters off our sw coast were colder. This year its the same. But a much larger area. We know what happened in winter 2003.

Its just a simple observation.

I think he will be right. If we get blocking and we,re the battle ground, makes interesting weather.

Redsunset

Kippure wrote: »

He,s right about one thing. BAck in 2003 atlantic waters off our sw coast were colder. This year its the same. But a much larger area. We know what happened in winter 2003.

Its just a simple observation.

I think he will be right. If we get blocking and we,re the battle ground, makes interesting weather.

yep for now im going along with the same past experience to happen or even worse.blocking will be very important for a great cold spell.time will tell.

Redsunset

The figure below shows that the predicted winter NAO index for 2009/10 is strongly positive at +1.4 with a standard error of ±1.0. The NAO prediction therefore favours above-normal temperatures and above-normal rainfall over northern Europe for Winter 2009/10.

Last year's observed NAO index was +0.2 (near neutral) and the prediction for 2009/10 is therefore consistent with warmer conditions over northern Europe, on average, than in Winter 2008/9 (when western parts of this region had below-normal temperatures).

The prediction is also consistent with a wetter winter than last year over northern Europe, much of which experienced below-average rainfall in Winter 2008/9.






this is how the met office is calling the mild winter conditions however mr red line (as in what is actually happening) is in a severe nose dive to being a negative NAO and perhaps a strong one too(meaning greater chance of that frigid siberian air).


one just looks at the chart and see's that we've had nearly all positive NAO since the early 80s,so that is why we kissed goodbye to our seasonal expected cold and snow.yes in between there was a couple of cold spells but nothing like the harsh winters we so loved in the past which we took so much for granted.


so im here still gonna call a cold one but if mr red line does decide to do a u turn,well then its curtains for mr snowman.

Kippure

More from Joe and a bit on el nino.


http://www.accuweather.com/video-on-demand.asp?video=41870064001&channel=VBLOG_BASTARDI&title=Is the Earth Cooling, or Is the Data Just Fooling

Redsunset

Kippure wrote: »

More from Joe and a bit on el nino.


http://www.accuweather.com/video-on-demand.asp?video=41870064001&channel=VBLOG_BASTARDI&title=Is the Earth Cooling, or Is the Data Just Fooling

ah very good i was just thinking watching it that the main driver is the solar cycle and it minimum then he goes and says it very briefly:rolleyes:

Kippure

redsunset wrote: »

ah very good i was just thinking watching it that the main driver is the solar cycle and it minimum then he goes and says it very briefly:rolleyes:

I,d say he,ll do a little summary on solar cycles soon. Infact ill ask him.;)

Redsunset

Kippure wrote: »

I,d say he,ll do a little summary on solar cycles soon. Infact ill ask him.;)

He did,i've posted it in ,The Sun is Dead thread

Redsunset

A white Christmas?
Chilly winter ahead
[FONT=Verdana,Arial,Helvetica]Issued: Saturday 3rd October 2009
Duty forecasters: Simon Keeling & Captain Bob [/FONT]


Whilst the pattern for the whole of the coming winter cannot be determined with any confidence, we do believe that the winter of 2009/10 could be a 'significant' event for both the UK and Continental Europe. It will be interesting to see how the pattern develops in the next few weeks and should give a firmer indication quite soon?



November
The new month looks likely to open with high pressure to the west of the British Isles and lower pressure to the south, a chilly and potentially unsettled easterly flow covering the south of the UK, northern areas should be dry at first under the influence of a ridge of high pressure although this may not last too long as developing low pressure to the northwest looks set to push unsettled weather through all areas. Rather unsettled and potentially disturbed with low pressure in control of the pattern and rather cool generally with a northwest to northerly flow, high pressure maintained to the west.
Once again it looks as though pressure will build strongly to the west with a potentially cold blast pushing south through the middle of the month, windy too with low pressure to the east accentuating the chilly feel. High pressure looks as though it then slowly transfer northeast across northern Britain with a chilly and strong north-easterly flow once more covering southern Britain. High pressure maintained to the north or northeast will keep the northern slice of the UK mainly settled but chilly, perhaps distinctly cold and windy, perhaps chilly enough for some wintriness in the precipitation.
For the latter stages of the month it looks as though conditions may turn milder as the flow switches around to the northwest then west, although the unsettled and windy weather is maintained for all areas.

December
Low pressure looks set to dominate the pattern throughout the opening couple of weeks of the month any drier and quieter weather is likely to be reserved for extreme regions of southern Britain and will be transitory. It'll often be windy and feeling distinctly chilly despite the flow being mainly from the west or northwest and periods of rain can be expected through all areas.
Somewhat milder for the middle of the month as the flow temporarily at least swings into the southwest and pressure rises mainly across the south of England. However there is a suggestion that a plunge of colder polar air will move south and east across all areas in the run up to the Christmas period, so some wintry precipitation is expected to affect all areas.
On all the available evidence at the moment Christmas Day looks likely to be cold with a showery northerly flow so a reasonable 'probability' of it being a white one somewhere in the UK! Turning less cold in the run up to New Year as the flow swings back to an Atlantic sourced north-westerly direction.

patneve

What surprises me is that high pressure seems to be on the cards AGAIN, starting from next Monday. This is strange, as we already had HP for weeks on end in September. HOWEVER, this high pressure could potentially give us some frosty nights :rolleyes:

Redsunset

The latest image from Jason-2, which can be seen at http://sealevel.jpl.nasa.gov/science/jason1-quick-look/2009/images/20090917P.jpg , reflects a 10-day data cycle centered around September 17, 2009.

It shows a series of warm "bumps" visible along the equator, denoted in the image by a black line. Known as Kelvin waves, these pools of warm water were triggered when the normally westward-blowing trade winds weakened in late July and again in early September, sending them sliding eastward from the western Pacific toward the Americas.

The Kelvin waves are 5 to 10 centimeters (2 to 4 inches) high, a few hundred kilometers wide and a few degrees warmer than surrounding waters. Traveling east at about 3 meters per second (6 miles per hour), they are expected to reach the coast of Peru in October.


For the past few months, the trade winds have weakened somewhat, but whether the new Kelvin waves traveling eastward across the Pacific will be adequate to pump this El Niño up enough to reinvigorate it and deliver any real impacts remains uncertain.

So what will El Niño 2009-2010 hold in store for the world this coming winter? In spite of the uncertainties, experienced climate forecasters around the world will continue to monitor the Pacific closely for further signs of El Niño development and will give it their best shot.

Unless present El Niño conditions intensify, this El Niño is too weak to have a major influence on many weather patterns.

If the trade winds decrease, the ocean waters will continue to warm and spread eastward, strengthening the El Niño.