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

Alles wat betrekking heeft op het buitenlands weer. Tropische stormen, orkanen, etc.

Karel
Berichten: 2779
Lid geworden op: 31-07-1978

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

Bericht door Karel » 05-06-2021 09:09

QBO 30 hPa mei :0.31 en dalend.

Negatief de komende winter!

Sebastiaan
Berichten: 7540
Lid geworden op: 31-12-1977

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

Bericht door Sebastiaan » 08-06-2021 09:30

Je hebt niet voldoende permissies om de bijlagen van dit bericht te bekijken.

Paul
Berichten: 695
Lid geworden op: 31-12-1979

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

Bericht door Paul » 10-06-2021 09:33

Artikel over de DBC Brewer Dobson, het mechanisme waarmee ozon van de tropen naar de polen wordt gevoerd.

Abstract
Observational and modeling evidence suggest a recent acceleration of the stratospheric Brewer-Dobson circulation (BDC), driven by climate change and stratospheric ozone depletion. However, slowly varying natural variability can compromise our ability to detect such forced changes over the relatively short observational record. Using observations and chemistry-climate model simulations, we demonstrate a link between multi-decadal variability in the strength of the BDC and the Interdecadal Pacific Oscillation (IPO), with knock-on impacts for composition in the stratosphere. After accounting for the IPO-like variability in the BDC, the modeled trend is approximately 7%–10% dec−1 over 1979–2010. Furthermore, we find that sea surface temperatures explain up to 50% of the simulated decadal variability in tropical mid-stratospheric ozone. Our findings demonstrate strong links between low-frequency variability in the oceans, troposphere and stratosphere, as well as their potential importance in detecting structural changes in the BDC and future ozone recovery.

https://agupubs.onlinelibrary.wiley.com ... 20GL092162

Sebastiaan
Berichten: 7540
Lid geworden op: 31-12-1977

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

Bericht door Sebastiaan » 14-06-2021 10:59

https://www.nature.com/articles/s43017-021-00173-9

Abstract | The stratospheric quasi- biennial oscillation (QBO) and the tropospheric Madden–Julian oscillation (MJO) are strongly linked in boreal winter. In this Review, we synthesize observational and modelling evidence for this QBO–MJO connection and discuss its effects on MJO telecon-nections and subseasonal- to- seasonal predictions. After 1980, observations indicate that, during winters when lower- stratospheric QBO winds are easterly, the MJO is ~40% stronger and persists roughly 10 days longer compared with when QBO winds are westerly. Global subseasonal fore-cast models, in turn, show a 1- week improvement (or 25% enhancement) in MJO prediction skill in QBO easterly versus QBO westerly phases. Despite the robustness of the observed QBO–MJO link and its global impacts via atmospheric teleconnections, the mechanisms that drive the con-nection are uncertain. Theories largely centre on QBO- related temperature stratification effects and subsequent impacts on deep convection, although other hypotheses propose that cloud radiative effects or QBO impacts on wave propagation might be important. Most numerical models, however, are unable to reproduce the observed QBO–MJO relationship, suggesting biases, deficiencies or omission of key physical processes in the models. While future work must strive to better understand all aspects of the QBO–MJO link, focus is needed on establishing a working mechanism and capturing the connection in models

Karel
Berichten: 2779
Lid geworden op: 31-07-1978

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

Bericht door Karel » 15-06-2021 14:15

Over de de variabiliteit (seizoen tot decaden) van de QBO en de nog onbekende oorzaken een artikel van Zane Martin, Adam Sobel, Amy Butler, Shuguang Wang. (15 JANUARY 2021)

https://repository.library.noaa.gov/vie ... 14_DS1.pdf

""Variability in QBO Temperature Anomalies on Annual and Decadal Time Scales.

ABSTRACT: The stratospheric quasi-biennial oscillation (QBO) induces temperature anomalies in the lower stratosphere and tropical tropopause layer (TTL) that are cold when lower-stratospheric winds are easterly and warm when winds are westerly. Recent literature has indicated that these QBO temperature anomalies are potentially important in influencing the tropical troposphere, and particularly in explaining the relationship between the QBO and the Madden–Julian oscillation (MJO). The authors examine the variability of QBO temperature anomalies across several time scales using reanalysis and observational datasets. The authors find that, in boreal winter relative to other seasons, QBO temperature anomalies are significantly stronger (i.e., colder in the easterly phase of the QBO and warmer in the westerly phase of the QBO) on the equator, but weaker off the equator. The equatorial and subtropical changes compensate such that meridional temperature gradients and thus (by thermal wind balance) equatorial zonal wind anomalies do not vary in amplitude as the temperature anomalies do. The same pattern of stronger on-equatorial and weaker off-equatorial QBO temperature anomalies is found on decadal time scales: stronger anomalies are seen for 1999–2019 compared to 1979–99. The causes of these changes to QBO temperature anomalies, as well as their possible relevance to the MJO–QBO relationship, are not known.""

Sebastiaan
Berichten: 7540
Lid geworden op: 31-12-1977

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

Bericht door Sebastiaan » 17-06-2021 21:07

Early hints of a weak Northern Hemisphere stratospheric polar vortex in November - consistent with a weak La Niña background. There is actually some skill at this lead time, especially for the multi-model ensemble.
https://twitter.com/WorldClimateSvc/sta ... 6250983426
Je hebt niet voldoende permissies om de bijlagen van dit bericht te bekijken.

Karel
Berichten: 2779
Lid geworden op: 31-07-1978

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

Bericht door Karel » 24-06-2021 09:05

Met de QBOE gaat het ook de goede kant op volgens de presentatie op 22 juni 2021. https://www.geo.fu-berlin.de/en/met/ag/ ... index.html
Afbeelding


Hoewel ik vanmorgen schrok van de laatste onjuiste presentatie van 23 juni 2021 op :

https://users.met.fu-berlin.de/~Aktuell ... eng&hem=nh

Afbeelding

Karel
Berichten: 2779
Lid geworden op: 31-07-1978

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

Bericht door Karel » 25-06-2021 13:09

De kaart van 24 juni 2021 ziet er weer goed uit. Blijkbaar automatisch een kaart van 23 juni 2020 gegenereerd op 23 juni 2021.

Afbeelding

Sebastiaan
Berichten: 7540
Lid geworden op: 31-12-1977

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

Bericht door Sebastiaan » 30-06-2021 11:41

https://twitter.com/CorwinWright/status ... 9348003841
Tweets over QBO-onderzoek

Prospect of increased disruption to the QBO in a changing climate
Abstract
The quasi-biennial oscillation (QBO) of tropical stratospheric winds was disrupted during the 2019/20 Northern Hemisphere winter. We show that this latest disruption to the regular QBO cycling was similar in many respects to that seen in 2016, but initiated by horizontal momentum transport from the Southern Hemisphere. The predictable signal associated with the QBO’s quasi-regular phase progression is lost during disruptions and the oscillation reemerges after a few months significantly shifted in phase from what would be expected if it had progressed uninterrupted. We infer from an increased wave-momentum flux into equatorial latitudes seen in climate model projections that disruptions to the QBO are likely to become more common in future. Consequently it is possible that in the future the QBO could be a less reliable source of predictability on lead times extending out to several years than it currently is.

Plain Language Summary
The quasi-biennial oscillation (QBO) consists of a regular switching between eastward and westward winds in the tropical stratosphere. The oscillation has persisted at least since its discovery in the 1960s, over which time its period averages about 28 months with some variability from cycle to cycle. Recently, during the Northern Hemisphere winters of 2015/16 and 2019/20, remarkable departures from this regular behaviour occurred that have no precedent in the observational record. Both the 2015/16 and 2019/20 QBO disruptions occurred when large horizontal fluxes of momentum intruded into the tropics from higher latitudes. Using climate model projections we find these horizontal fluxes are likely to increase in future, suggesting an increased future likelihood of QBO disruptions and a concomitant loss in QBO predictability.

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