Scholarlink

<p>The Arctic Stratospheric Polar Vortex (SPV) is known for its high interannual variability, with major Sudden Stratospheric Warmings (SSWs) occurring approximately every second year and with three Exceptionally Strong Vortex (ESV) events in the past decades, which are associated with springtime ozone depletion. Understanding the dynamical and morphological properties of the SPV is crucial for predicting these extreme events, and SPV variability in general. This study utilizes data from 45 Northern Hemisphere (NH) extended winter seasons, covering the period from September to May, at lower, middle and upper stratosphere heights. We explore the influence of different climate variability modes on the vortex’s dynamical properties. We introduced the SPV metrics, which provide a holistic overview of SPV intensity, and found a strong correlation (0.83) with the zonal wind. In February, March and April (FMA) of the 2019 NH winter, the climatological anomaly reached an all-time high of SPV strength, with record-low ozone due to an ESV, though its intensity did not extend to the upper stratosphere. Other ESV winters were 1996 and 2010. The EPV gradient increases more sharply with altitude than the area, indicating a stronger upper stratospheric vortex boundary that resists tropospheric wave disturbances. During some SSW events, the vortex area may recover, but the EPV gradient remains weak. The SPV center shows a significant poleward shift toward Eurasia at &#xa0;14.31 km/year, linked to vortex dynamics. Minimal latitudinal displacement occurred during 1989–1995 (no extreme events), while greater shifts during 1998–2009 coincided with frequent SSWs. SPV metrics correlated with SPV position of (0.55) peak winter and (0.66) FMA. We quantify climatic variability and its role in extreme SPV events, highlighting the significant influence of the Quasi-Biennial Oscillation and Arctic Oscillation. Breakup timing, influenced by tropospheric waves, shows minor variations across levels. The vortex begins forming in the upper levels and dissipates progressively from the lower stratosphere. Notably, a statistically significant decreasing trend towards earlier vortex formation is seen in the upper stratosphere. We analysed the interannual variability of Polar Stratospheric Clouds and their relationship with SPV dynamics and associated ozone loss during late winter and early spring. We hypothesized that both SSWs and ESVs could potentially occur in a single NH winter in future.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

A 45-year climatological study of arctic stratospheric polar vortex dynamics and morphology using ERA5 data (1979–2023)

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年10月17日

查看全文
  • Anish Kumar,
  • Khalil Karami,
  • Christoph Jacobi

摘要

The Arctic Stratospheric Polar Vortex (SPV) is known for its high interannual variability, with major Sudden Stratospheric Warmings (SSWs) occurring approximately every second year and with three Exceptionally Strong Vortex (ESV) events in the past decades, which are associated with springtime ozone depletion. Understanding the dynamical and morphological properties of the SPV is crucial for predicting these extreme events, and SPV variability in general. This study utilizes data from 45 Northern Hemisphere (NH) extended winter seasons, covering the period from September to May, at lower, middle and upper stratosphere heights. We explore the influence of different climate variability modes on the vortex’s dynamical properties. We introduced the SPV metrics, which provide a holistic overview of SPV intensity, and found a strong correlation (0.83) with the zonal wind. In February, March and April (FMA) of the 2019 NH winter, the climatological anomaly reached an all-time high of SPV strength, with record-low ozone due to an ESV, though its intensity did not extend to the upper stratosphere. Other ESV winters were 1996 and 2010. The EPV gradient increases more sharply with altitude than the area, indicating a stronger upper stratospheric vortex boundary that resists tropospheric wave disturbances. During some SSW events, the vortex area may recover, but the EPV gradient remains weak. The SPV center shows a significant poleward shift toward Eurasia at  14.31 km/year, linked to vortex dynamics. Minimal latitudinal displacement occurred during 1989–1995 (no extreme events), while greater shifts during 1998–2009 coincided with frequent SSWs. SPV metrics correlated with SPV position of (0.55) peak winter and (0.66) FMA. We quantify climatic variability and its role in extreme SPV events, highlighting the significant influence of the Quasi-Biennial Oscillation and Arctic Oscillation. Breakup timing, influenced by tropospheric waves, shows minor variations across levels. The vortex begins forming in the upper levels and dissipates progressively from the lower stratosphere. Notably, a statistically significant decreasing trend towards earlier vortex formation is seen in the upper stratosphere. We analysed the interannual variability of Polar Stratospheric Clouds and their relationship with SPV dynamics and associated ozone loss during late winter and early spring. We hypothesized that both SSWs and ESVs could potentially occur in a single NH winter in future.