Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2021-2022

Alles wat betrekking heeft op het buitenlands weer. Tropische stormen, orkanen, etc.
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Karel
Berichten: 2869
Lid geworden op: 31-07-1978

Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2021-2022

Bericht door Karel » 18-09-2021 16:32

Sebastiaan schreef:
17-09-2021 10:53
EC en UKMO voor december.
Aangenomen dat er in de komende winter een warme stratosfeer is. Wat kan dat voor de volgende januari betekenen?
Volgens Ben Nollhttps://twitter.com/bennollweather In de volgende decembermaanden een warme stratosfeer.
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De follow-up in de stratosfeer in januari in de jaren 2019, 2004, 2002, 2001, 1999, 1998, 1988, 1969, 1961 na de zeer warme stratosfeer in de voorgaande december. Er zijn echter meer factoren werkzaam zoals ENSO-fase, QBO en MJO de komende winter.
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Sebastiaan
Berichten: 7806
Lid geworden op: 31-12-1977

Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2021-2022

Bericht door Sebastiaan » 19-09-2021 14:27

Vreemd vind ik de berekening van EC niet.

Zie hieronder. Dus ik zou het wel enig krediet willen geven.
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Sebastiaan
Berichten: 7806
Lid geworden op: 31-12-1977

Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2021-2022

Bericht door Sebastiaan » 26-09-2021 11:36

This study investigates the combined effect of the El Niño–Southern Oscillation (ENSO) and stratospheric quasi-biennial oscillation (QBO) on the Madden Julian Oscillation (MJO). The results show that the western Pacific MJO originating from the Indian Ocean during La Niña/QBO easterly years is stronger than that during El Niño years. This relation, however, disappears during La Niña/QBO westerly years. The reason is that ENSO and the QBO have different effects on each MJO event. For an El Niño year, there is only about one MJO event, and the QBO effect is small. During a La Niña/QBO easterly year, there are 1.7 MJO events, while during a La Niña/QBO westerly year, there are only 0.6 MJO events. El Niño can reinforce the MJO over the western Pacific because of the positive moisture advection of the El Niño mean state by MJO easterly wind anomalies. The QBO mainly affects the MJO over the Maritime Continent region by changing the high-cloud-controlled diurnal cycle; and the Maritime Continent barrier effect is enhanced during the QBO westerly phase because of the strong diurnal cycle. During El Niño years, even the MJO over the Maritime Continent is suppressed by the QBO westerly phase; the MJO can be reinforced over the western Pacific. During La Niña/QBO westerly years, the MJO over the Maritime Continent is suppressed because of the strong Maritime Continent diurnal cycle, and it is further suppressed over the western Pacific because of the lack of a reinforcement process. https://www.tandfonline.com/doi/full/10 ... 19.1588064

Karel
Berichten: 2869
Lid geworden op: 31-07-1978

Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2021-2022

Bericht door Karel » 27-09-2021 08:04

Ook de NAO fase heeft invloed op de MJO. Na een sterke NAO-- fase is (3)MJO krachtig en meer waarschijnlijk. Na een sterke NAO++ fase is (7) MJO krachtig en meer waaschijnlijk. https://journals.ametsoc.org/view/journ ... b_body=pdf

"NAO Influence on the MJO and its Prediction Skillin the Subseasonal-to-Seasonal Prediction Models in Journal of Climate.

Abstract
Based on the database of the Subseasonal to Seasonal (S2S) Prediction project of the World Weather 28Research Programme (WWRP) / World Climate Research Programme (WCRP), the influence of the North Atlantic Oscillation (NAO) on the Madden‐Julian Oscillation (MJO) and its forecast skill is investigated. It is found that most models can capture the MJO phase changes following positive and negative NAO events.About 20 days after initialized with a positive (negative) NAO, the forecast MJO appears more frequently in phase 7 (3), which corresponds to reduced (enhanced) convection in the tropical Indian Ocean and enhanced (suppressed) convection in the western Pacific. In most S2S models the MJO prediction skill is dependent on the NAO amplitude and phase in the initial condition. A strong NAO leads to a better MJO forecast skill than a weak NAO. The MJO skill tends to be higher when the forecast starts from a negative NAO than a positive NAO. These results indicates that there is a strong Northern extratropical influence on the MJO and its forecast skill.It is important for numerical models to better represent the NAO influence to improve the simulation and prediction of the MJO"

Sebastiaan
Berichten: 7806
Lid geworden op: 31-12-1977

Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2021-2022

Bericht door Sebastiaan » 01-10-2021 09:32

Abstract. The number of sudden stratospheric warmings (SSWs) per year is affected by the phase of the El Niño–Southern Oscillation (ENSO), yet there are discrepancies between the observed and modeled relationship. We investigate how systematic model biases may affect the ENSO-SSW connection. A two-step bias-correction process is applied to the troposphere, stratosphere or full atmosphere of an atmospheric general circulation model. ENSO type sensitivity experiments are then performed to reveal the impact of differing climatologies on the ENSO–SSW teleconnection.

The number of SSWs per year is overestimated in the control run, and this statistic is improved when stratospheric biases are reduced. The seasonal cycle of SSWs is also improved by the bias corrections. The composite SSW responses in the stratospheric zonal wind, geopotential height and surface response are well represented in both the control and bias corrected runs. The model response of SSWs to ENSO phase is more linear than in observations, in line with previous modelling studies, and this is not changed by the reduced biases. However, the trend of more wave-1 events during El Niño years than La Niña years is improved in the bias corrected runs.

https://wcd.copernicus.org/preprints/wcd-2021-62/

Sebastiaan
Berichten: 7806
Lid geworden op: 31-12-1977

Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2021-2022

Bericht door Sebastiaan » 02-10-2021 11:38

https://agupubs.onlinelibrary.wiley.com ... 19GL084683
Our findings demonstrate that the subseasonal teleconnections from the MJO to the NAE weather regimes are strongly dependent on the ENSO background state (summary schematic: Figure 4). The NAO+ regime tropospheric teleconnection from MJO phases 1–5 is strongly enhanced during El Niño years, persisting throughout more MJO phases, while it is suppressed during La Niña years. The NAO − regime teleconnection via the stratosphere from MJO phases 7–8 is most enhanced and occurring latest during La Niña years, while it is suppressed during El Niño years. Neutral years feature aspects of both of these teleconnections. NAE regime progression, in situ development, and the differing dynamical teleconnection mechanisms also become clearer via this perspective separated by ENSO state. The ENSO circullation anomaly modifies the MJO convection, impacting the Rossby waves generated, and their teleconnection pathways to the NAE region.
The changes in the weather regime distributions present evidence of the rectification of subseasonal teleconnections onto the seasonal mean. This rectification implies that it is important to have a good representation of this subseasonal teleconnection in any general circulation model used to study climate states and their interactions
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Karel
Berichten: 2869
Lid geworden op: 31-07-1978

Re: Ontwikkeling van de QBO, zonneactiviteit, ENSO, MJO en de winter 2021-2022

Bericht door Karel » 12-10-2021 15:54

Inderdaad de MJO en de stratosfeer kunnen nog anders dan een zeer zachte januari/februari 2022 bepalen. De modelberekeningen voor deze winter wijzen niet in deze richting. https://effis.jrc.ec.europa.eu/apps/eff ... forecasts/
De komende winter wordt een Central Pacific La Niña winter. Nu al zijn de temperatuurafwijkingen in de Central Pacific het hoogst.

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Als deze factor overheersend wordt dan staat ons een zachte winter te wachten waar nu sterk naar verlangd wordt in mijn omgeving.
Zie publicatie:https://iopscience.iop.org/article/10.1 ... 7/1/012043

Interannual climate anomalies in the Atlantic-European region associated with La-Nina types
E N Voskresenskaya

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