Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Alles wat betrekking heeft op het buitenlands weer. Tropische stormen, orkanen, etc.
Paul
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Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Bericht door Paul » 10-12-2020 19:05

Sorry, mislukt bericht
Laatst gewijzigd door Paul op 11-12-2020 10:28, 1 keer totaal gewijzigd.

Sebastiaan
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Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Bericht door Sebastiaan » 10-12-2020 21:42

Een deel van de uitvoer gaat voor fase 6,7. We wachten af. http://apps.ecmwf.int/webapps/openchart ... 2012100000
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Sebastiaan
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Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Bericht door Sebastiaan » 11-12-2020 11:49

Nieuw artikel Butler. https://www.nature.com/articles/s43247-020-00060-z
The stratosphere, the layer of the atmosphere at heights between 10-50 km, is an important source of variability for the weather and climate at the Earth’s surface on timescales of weeks to decades. Since the stratospheric circulation evolves more slowly than that of the troposphere below, it can contribute to predictability at the surface. Our synthesis of studies on the coupling between the stratosphere and the troposphere reveals that the stratosphere also contributes substantially to a wide range of climate-related extreme events. These extreme events include cold air outbreaks and extreme heat, air pollution, wildfires, wind extremes, and storm clusters, as well as changes in tropical cyclones and sea ice cover, and they can have devastating consequences for human health, infrastructure, and ecosystems. A better understanding of the vertical coupling in the atmosphere, along with improved representation in numerical models, is therefore expected to help predict extreme events on timescales from weeks to decades in terms of the event type, magnitude, frequency, location, and timing. With a better understanding of stratosphere-troposphere coupling, it may be possible to link more tropospheric extremes to stratospheric forcing, which will be crucial for emergency planning and management.

Karel
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Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Bericht door Karel » 11-12-2020 16:41

Sebastiaan schreef:
11-12-2020 11:49
Nieuw artikel Butler. https://www.nature.com/articles/s43247-020-00060-z
The stratosphere, the layer of the atmosphere at heights between 10-50 km, is an important source of variability for the weather and climate at the Earth’s surface on timescales of weeks to decades. Since the stratospheric circulation evolves more slowly than that of the troposphere below, it can contribute to predictability at the surface. Our synthesis of studies on the coupling between the stratosphere and the troposphere reveals that the stratosphere also contributes substantially to a wide range of climate-related extreme events. These extreme events include cold air outbreaks and extreme heat, air pollution, wildfires, wind extremes, and storm clusters, as well as changes in tropical cyclones and sea ice cover, and they can have devastating consequences for human health, infrastructure, and ecosystems. A better understanding of the vertical coupling in the atmosphere, along with improved representation in numerical models, is therefore expected to help predict extreme events on timescales from weeks to decades in terms of the event type, magnitude, frequency, location, and timing. With a better understanding of stratosphere-troposphere coupling, it may be possible to link more tropospheric extremes to stratospheric forcing, which will be crucial for emergency planning and management.
Dank Sebastiaan voor deze informatie over de prioriteiten voor het stratosfeeronderzoek.
Aanvullend een review voor Reviews of Geophysics van mark p. baldwin et al met een samenvatting van de kennis over Sudden Stratospheric Warmings tot nu toe.https://www.researchgate.net/profile/Ma ... rmings.pdf

Sebastiaan
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Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Bericht door Sebastiaan » 12-12-2020 11:08

The ship has sailed for any link to Northern blocking. But...There's increasing evidence for additional Pacific "help" in the form of further MJO activity in phases 4-5-6 within the wk. This needs watching closely as it may still aid in a cold Xmas due to N Atlantic amplification.
https://twitter.com/MattHugo81/status/1 ... 9313020933

We zien dus een mogelijke transitie van MJO fase 4, 5 naar 6. Bij EC meer dan bij GFS. Hoe groener de kleur hoe beter ;)
MJO-verwachtingen gaan regelmatig de mist in en we kijken dus naar een gemiddelde. Logisch dat dit de amplitude verzwakt. Dus we moeten echt afwachten.
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Sebastiaan
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Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Bericht door Sebastiaan » 13-12-2020 20:56

Uitstekende uitleg op NW.
Current State?

We have a northern latitude set up and ongoing weakening of polar winds that are absolutely wipe for northern blocking to take hold due to ongoing weakening of the vortex caused by wave 1 and wave 2 activity the past 4 weeks.

What do we need to take advantage?

Amplification

How do we create amplification?

By creating a rise in angular momentum (AAM)

What can increase angular momentum?

MJO - Tropical convection that moves east into areas of the globe known as the western pacific and central pacific (these are phases 6 7 and 8. Initial forecasts were for a move into 6 and 7 low amp 8 then dieing. Current forecasts show this struggling to get going into 6 which affects its move into 7. Since November this has been under forecast until nearer to time. So no need to worry just yet. Its the NINA we are currently in thats counter acting this. We obviously have cooler waters in the pacific at the minute.

Torque events - This is the current wild card. We have a moderate event an East Asian Mountain Torque (+EAMT) happening right now peaking next Monday or Tuesday as high pressure moves over the Himalayas pushing east into Asia. We also have a forecasted MUCH stronger event due around Christmas time.

What happens if both the convective rain moved east (MJO phases 5 6 and 7) at the same time as the forcing from the torque events?

We get a rise in AAM (angular momentum) from a base state that isn't that low to start with its just a little above neutral.

What happens if AAM rises?

We get our amplification. Remember the polar field is susceptible right now. Zonal winds are dropping like stones and we have an arctic high waiting for a ridge to come join it from the south to create a winter dance.

I know the MJO is showing signs of dieing before it gets going but this isn't a certainty the models keep getting it wrong and underestimating it and we have 2 moderate and another strong event almost in the bag.

This year if might not even matter if the MJO runs out or poof and we just have the torque events as the polar atmosphere is so susceptible from the polar high and strat weakening from novembers wave attacks.

Sebastiaan
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Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Bericht door Sebastiaan » 14-12-2020 09:19

https://climate.copernicus.eu/charts/c3 ... umemembers
Nieuwe kaarten bij copernicus. O.a. stratosfeer.
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Sebastiaan
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Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Bericht door Sebastiaan » 14-12-2020 09:23

The ensembles have a strong signal by the end of the run of a large anticyclone descent in East Asia. Here comes the next +EAMT late Dec.
https://twitter.com/antmasiello/status/ ... 8438737925

EAMT = east asia mountain torgue

Karel
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Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Bericht door Karel » 16-12-2020 20:40

Sebastiaan schreef:
14-12-2020 09:23
The ensembles have a strong signal by the end of the run of a large anticyclone descent in East Asia. Here comes the next +EAMT late Dec.
https://twitter.com/antmasiello/status/ ... 8438737925

EAMT = east asia mountain torgue
Ook de GFS oper van 1200u laat in de stratosfeer het effect van de verschillende impulsen vanaf Alaska over het arctisch gebied naar de Himalaya zien.
Afbeelding
Afbeelding

Sebastiaan
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Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2020/2021

Bericht door Sebastiaan » 18-12-2020 11:28

http://agupubs.onlinelibrary.wiley.com/ ... 18GL077098

Plain Language Summary

The stratosphere is a layer of the atmosphere far from the Earth’ssurface (10–50 km above the surface), but changes in stratospheric circulation, particularly events knownas sudden stratospheric warmings, affect the weather and climate at the surface. By flattening individualmountain regions in a climate model that extends from the Earth’s surface far past the stratosphere, westudy the effects of mountains on stratospheric circulation and the frequency of sudden stratosphericwarming events. We find that the presence of the Mongolian mountains weakens the stratospheric jet by athird of its strength and creates 6 times more warming events as there would be without these mountains.The impact of the Mongolian mountains is about twice as large as the impact of the larger and moreexpansive Tibetan plateau and Himalaya. Mountains are a source of planetary-scale atmospheric wavesthat propagate upward into the stratosphere; we findthat the mountain effect on the stratosphere is largelybecause the mountains alter the pathway that all waves take as they propagate toward the stratosphere,through the influence the mountains have on circulation lower down in the atmosphere. We find similaranomalous wave propagation during sudden warming events in the model and observation.

Dit is m.i. een belangrijke studie ivm eamt komende tijd.

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