Maar het drukpatroon gedurende de rest van het afgelopen jaar heeft geen voorspellende waarde. Althans, dat is niet bekend.
WCS kan wel iets beweren, maar het bewijs is toch nog niet geleverd, of heb ik iets gemist?
Je zegt verder het volgende: "Vorige winter was heel bijzonder qua hoeveelheden ozon in de bovenlucht boven de Noordpool, vaak warm op grote hoogte. Dit jaar is dat veel minder, dat zou een aanwijzing kunnen zijn dat de poolwervel sterker is dit jaar, wat kan leiden tot minder noordelijke blokkades."
Is van hoeveelheden ozon op een bepaald moment in de bovenlucht boven de Noordpool bekend dat ze een voorspellende waarde hebben en zo ja, geldt dat ook voor de late herfst en zo ja voor hoe lang vooruit?
[...]
Gisteren gaf ik al dat ik dat betreur dat er niet meer details zijn vrijgegeven aangezien ik vind dat wetenschappelijk inzichten altijd gedeeld moeten worden. Zeker als er zo´n groot maatschappelijk belang is.
De relatie tussen meer geblokkeerde patronen en de activiteit van de zon is terug te vinden in het onderzoek van Lockwood. Je kan dat na lezen op de verdiepingsforum.
Over de relatie tussen ozon en de temperatuur kan je hieronder een en ander lezen
The stratosphere is the layer of the atmosphere situated between 10km and 50km above the earth. It is situated directly above the troposphere, the first layer of the atmosphere that is directly responsible for the weather that we receive. The boundary between the stratosphere and the troposphere is known as the tropopause. The air pressure ranges from around 100hPa at the lower levels to around 1hPa at the upper levels. The middle stratosphere is often considered to be around the 30hPa level.
Every winter the stratosphere cools down dramatically as less solar UV radiation is absorbed by the ozone content in the stratosphere. The difference in the temperature between the North Pole and the latitudes further south creates a strong vortex – the wintertime stratospheric polar vortex. The colder the stratosphere, the stronger this vortex becomes. The stratospheric vortex has a strong relationship with the tropospheric vortex below. The stronger the stratospheric vortex, the stronger the tropospheric vortex becomes.
The strength and position of the tropospheric vortex influences the type of weather that we are likely to experience. A strong polar vortex is more likely to herald a positive AO with the resultant jet stream track bringing warmer wet southwesterly winds. A weaker polar vortex can contribute to a negative AO with the resultant mild wet weather tracking further south.
Last year the start of the stratospheric winter saw the stratosphere cool down far less than recent years. This was probably due to an enhanced Brewer-Dobson Circulation (BDC) which resulted in more ozone being transported from the tropical stratosphere to the polar stratosphere and a warmer polar stratosphere as a result.
One of the reasons the BDC was enhanced was because the solar minimum coincided with an easterly or negative QBO. The Quasi-Biennial Oscillation (QBO) is a major influence on the stratosphere. This is a tropical stratospheric wind or gravity pulse that has a rough two year cycle. This wind descends from the top of the stratosphere towards the troposphere in an either westerly or easterly direction. This year the QBO is in a westerly phase. The westerly phase flows in the same direction as the polar vortex circulation which does nothing to inhibit the flow, and the BDC is also reduced in a westerly phase. Therefore this year the polar vortex is likely to be stronger than last and as a result high latitude blocking is less likely.
One thing that we can hope for though is a Sudden Stratospheric Warming (SSW) or also known as Major Midwinter Warmings (MMW).These are caused by large-scale planetary waves being deflected up into the stratosphere and towards the North Pole, often after a strong mountain torque event. These waves can seriously disrupt the stratospheric vortex, leading to a slowing or even reversal of the vortex. This can occur by the vortex being displaced off the pole – a displacement SSW, or by the vortex being split in two – a splitting SSW.
http://forum.netweather.tv/topic/64621-stratosphere-temperature-watch/
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