The Nature of the Arctic Oscillation and Diversity of the Extreme Surface Weather Anomalies It Generates

Dai, Panxi; Tan, Benkui

doi:10.1175/jcli-d-16-0467.1

Cited by 30 publications

(12 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The correlation coefficient between the May−July AO and the persistence of the positive EWD pattern was -0.45, which is statistically significant at the 95% confidence level. The AO is a primary mode of atmospheric variability over the extratropics of the Northern Hemisphere, and is significantly connected to the atmospheric circulations over the mid-to-lower latitudes (Park et al 2011, Dai & Tan 2017. indicated that the influence of the spring AO on the following East Asian summer monsoon became obvious and significant during the mid-1970s to mid-1990s.…”

Section: Discussionmentioning

confidence: 99%

Characteristics of atmospheric circulation patterns over East Asia and their impacts on precipitation in summer

Li¹,

Feng²,

Hou³

et al. 2019

Clim. Res.

View full text Add to dashboard Cite

We investigated 3 summer atmospheric circulation patterns over the mid-latitudes of East Asia-the monopole (MOP), East Asia−Pacific (EAP) and southeast−northwest out-of-phase dipole (EWD)-and their impacts on precipitation in eastern China. Our results show that an increase in the frequency of the positive MOP pattern enhances precipitation in northeastern China, while a longer persistence of this pattern induces above-average precipitation in the midto-lower reaches of the Yangtze River valley (MLRYR). For the negative MOP pattern, a higher frequency of this pattern leads to below-average precipitation in northeastern and southern China, while its persistence has insignificant influences on precipitation in eastern China. Increases in the frequency and persistence of the positive EAP pattern intensify precipitation in the MLRYR. For the negative EAP pattern, increases in the frequency and persistence of the pattern reduce precipitation in the MLRYR, and a higher frequency of this pattern markedly intensifies precipitation in northern China. Regarding the positive EWD pattern, an increase in its frequency favors below-average precipitation in northern China, and an increase in its persistence clearly intensifies precipitation in the MLRYR. Increases in the frequency and persistence of the negative EWD pattern produce below-(above-)average precipitation in the MLRYR (north eastern China), with a longer persistence of this pattern especially reducing precipitation in the MLRYR. These results indicate that the frequency and persistence of each pattern have different impacts on precipitation in eastern China.

show abstract

Section: Discussionmentioning

confidence: 99%

Characteristics of atmospheric circulation patterns over East Asia and their impacts on precipitation in summer

Li¹,

Feng²,

Hou³

et al. 2019

Clim. Res.

View full text Add to dashboard Cite

show abstract

“…A wide range of phenomena have been proposed as potential sources of predictability for the winter AO, with time scales of seasons to decades (e.g., Smith et al, 2016). Among other factors, AO skill could arise from tropical climate anomalies, including ENSO (Dai & Tan, 2017;Dunstone et al, 2016;Tang et al, 2007;Yu & Lin, 2016), as well as Arctic sea ice (Wang et al, 2017), Eurasian snow cover (Cohen et al, 2010), and stratospheric-tropospheric coupling (Butler et al, 2016;Sigmond et al, 2013). Whatever mechanisms are responsible for AO skill, it would seem that only now have state-of-the-art forecasting systems been able to represent them with sufficient accuracy, either through improved physics, better data assimilation, or improved observing networks.…”

Section: Introductionmentioning

confidence: 99%

Strong Relations Between ENSO and the Arctic Oscillation in the North American Multimodel Ensemble

L’Heureux

Tippett

Kumar

et al. 2017

Geophysical Research Letters

View full text Add to dashboard Cite

Arctic Oscillation (AO) variability impacts climate anomalies over the middle to high latitudes of the Northern Hemisphere. Recently, state‐of‐the‐art climate prediction models have proved capable of skillfully predicting the AO during the winter, revealing a previously unrealized source of climate predictability. Hindcasts from the North American Multimodel Ensemble (NMME) show that the seasonal, ensemble mean 200 hPa AO index is skillfully predicted up to 7 months in advance and that this skill, especially at longer leads, is coincident with previously unknown and strong relations (r > 0.9) with the El Niño–Southern Oscillation (ENSO). The NMME is a seasonal prediction system that comprises eight models and up to 100 members with forecasts out to 12 months. Observed ENSO‐AO correlations are within the spread of the NMME member correlations, but the majority of member correlations are stronger than observed, consistent with too high predictability in the model, or overconfidence.

show abstract

“…Similarly, in the case of heat waves, strong geopotential anomalies were observed in the upper parts of the troposphere, although they were positive (Chen et al, ; Tomczyk et al, , ). Analysing the upper troposphere, disturbances were found useful in following the process of the Arctic Oscillation's formation and propagation (Dai and Tan, ). Tomassini et al () related the extreme winter cold spells over Northern Europe to preceding circulation anomalies in the stratosphere (weakening in the stratospheric polar vortex); several cold spells occurred in association with a downward propagating dynamical disturbance which originated in the stratosphere.…”

Section: Discussion and Summarymentioning

confidence: 99%

Cold spells in Poland and Germany and their circulation conditions

Tomczyk

Bednorz

Sulikowska

2019

Intl Journal of Climatology

View full text Add to dashboard Cite

The primary objective of this paper was to determine the circulation conditions of the occurrence of cold spells in Poland and Germany. The observed inconsiderable warming slightly contributed to a change in the number of cold days and cold spells. The occurrence of cold spells in Poland and Germany was related to considerably more active and intensive pressure systems than on average in the winter season in the studied years. A strong high pressure system was located over much of the continent, blocking westerly circulation. During the occurrence of cold spells, negative anomalies of isobaric surface heights were recorded with the greatest anomalies being in the 300-250 hPa heights. The highest air temperature anomalies were recorded on the lowest isobaric levels, where they amounted to <−10 C. On average, anomalies on the 300 hPa isobaric level began developing approximately 9 days before the beginning of cold spells over the study area. The decay of cold spells was not related to rapid exchange of air masses, but rather to gradual weakening of anomalies in the upper troposphere, and their shifting westwards.

show abstract

The Nature of the Arctic Oscillation and Diversity of the Extreme Surface Weather Anomalies It Generates

Cited by 30 publications

References 45 publications

Characteristics of atmospheric circulation patterns over East Asia and their impacts on precipitation in summer

Characteristics of atmospheric circulation patterns over East Asia and their impacts on precipitation in summer

Strong Relations Between ENSO and the Arctic Oscillation in the North American Multimodel Ensemble

Cold spells in Poland and Germany and their circulation conditions

Contact Info

Product

Resources

About