Solar cycle modulation of the Arctic Oscillation in a chemistry-climate model

AbstractThe parasol effect of volcanic dust and aerosol caused by volcanic eruption results in the deepening and strengthening of the Arctic vortex system, thus stimulating or strengthening the Arctic Oscillation (AO). Three of the strongest AOs in more than a century have been linked to volcanic eruptions. Every significant fluctuation of the AO index (AOI = ΔH_middle latitudes − ΔH_Arctic) for many years has been associated with a volcanic eruption. Volcanic activity occurring at different locations in the Arctic vortex circulation will exert different effects on the polar vortex.

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Assessment of the Arctic Oscillation influence on the formation of the Arctic Ocean circulation regimes for the last decades

10.1117/12.2603394 ◽

2021 ◽

Author(s):

Egor E. Lemeshko

Keyword(s):

Arctic Ocean ◽

Ocean Circulation ◽

Arctic Oscillation ◽

The Arctic ◽

The Arctic Ocean ◽

The Arctic Oscillation ◽

Arctic Ocean Circulation

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Analysis of Arctic Spring Ozone Anomaly in the Phases of QBO and 11-year Solar Cycle for 1979–2011

10.20944/preprints202104.0057.v1 ◽

2021 ◽

Author(s):

Yousuke Yamashita ◽

Hideharu Akiyoshi ◽

Masaaki Takahashi

Keyword(s):

Solar Cycle ◽

Climate Model ◽

Polar Vortex ◽

Reanalysis Data ◽

Early Spring ◽

The Arctic ◽

Negative Anomaly ◽

Late Winter ◽

Quasi Biennial Oscillation ◽

Biennial Oscillation

Arctic ozone amount in winter to spring shows large year-to-year variation. This study investigates Arctic spring ozone in relation to the phase of quasi-biennial oscillation (QBO)/the 11-year solar cycle, using satellite observations, reanalysis data, and outputs of a chemistry climate model (CCM) during the period of 1979–2011. For this duration, we found that the composite mean of the Northern Hemisphere high-latitude total ozone in the QBO-westerly (QBO-W)/solar minimum (Smin) phase is slightly smaller than those averaged for the QBO-W/Smax and QBO-E/Smax years in March. An analysis of a passive ozone tracer in the CCM simulation indicates that this negative anomaly is primarily caused by transport. The negative anomaly is consistent with a weakening of the residual mean downward motion in the polar lower stratosphere. The contribution of chemical processes estimated using the column amount difference between ozone and the passive ozone tracer is between 10–20% of the total anomaly in March. The lower ozone levels in the Arctic spring during the QBO-W/Smin years are associated with a stronger Arctic polar vortex from late winter to early spring, which is linked to the reduced occurrence of sudden stratospheric warming in the winter during the QBO-W/Smin years.

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Climate Extremes of the 2019/2020 Winter in Northern Eurasia: Contributions by the Climate Trend and Interannual Variability Related to the Arctic Oscillation

Meteorologiya i Gidrologiya ◽

10.52002/0130-2906-2021-2-5-16 ◽

2021 ◽

pp. 5-16

Author(s):

V. N. Kryjov ◽

Keyword(s):

Interannual Variability ◽

Arctic Oscillation ◽

Global Climate ◽

Linear Trend ◽

Climate Extremes ◽

The Arctic ◽

Northern Eurasia ◽

Climate Trend ◽

Temperature And Precipitation ◽

The Arctic Oscillation

The 2019/2020 wintertime (December–March) anomalies of sea level pressure, temperature, and precipitation are analyzed. The contribution of the 40-year linear trend in these parameters associated with global climate change and of the interannual variability associated with the Arctic Oscillation (AO) is assessed. In the 2019/2020 winter, extreme zonal circulation was observed. The mean wintertime AO index was 2.20, which ranked two for the whole observation period (started in the early 20th century) and was outperformed only by the wintertime index of 1988/1989. It is shown that the main contribution to the 2019/2020 wintertime anomalies was provided by the AO. A noticeable contribution of the trend was observed only in the Arctic. Extreme anomalies over Northern Eurasia were mainly associated with the AO rather than the trend. However, the AO-related anomalies, particularly air temperature anomalies, were developing against the background of the trend-induced increased mean level.

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