Scholarlink

<p>The Northeast China Cold Vortex (NCCV) is a pivotal synoptic-scale system affecting summer weather and climate in Northeast Asia. However, its isolated impact on precipitation in the Yangtze-Huaihe River Basin (YHRB) remains unclear, largely due to interference from low-latitude circulation systems. Using multivariate empirical orthogonal function (MVEOF) analysis and atmospheric moisture budget diagnostics, this study investigates the role of the NCCV within the 10–40-day moisture intraseasonal oscillation (MISO). We find that the NCCV alone does not directly drive rainfall over the YHRB. Its influence depends strongly on the phase of the MISO. The NCCV significantly enhances rainfall intensity over the YHRB specifically during MISO phases 4–5, when an anticyclonic moisture circulation anomaly over the western North Pacific supplies abundant moisture. During these phases, the NCCV, appearing as a cyclonic circulation anomaly to the north, interacts synergistically with the southern anticyclone. This interaction strengthens low-level wind convergence, intensifies vertical moisture advection, and favors heavy rainfall. In other MISO phases, the impact of the NCCV remains weak. Our results highlight the MISO as the primary regulator of YHRB rainfall and demonstrate that the influence of the NCCV is realized only during specific moisture-favorable dynamic windows.</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

Intraseasonal moisture transport reveals the true impact of the Northeast China cold vortex on Yangtze-Huaihe River Basin rainfall

  • 期刊论文

  • 发表日期：

    2026年5月28日

查看全文
  • Fang Zhou,
  • Yihe Fang,
  • Ran An,
  • Zefan Ju,
  • Shengnan Zhou,
  • Zuxiang Yang

摘要

The Northeast China Cold Vortex (NCCV) is a pivotal synoptic-scale system affecting summer weather and climate in Northeast Asia. However, its isolated impact on precipitation in the Yangtze-Huaihe River Basin (YHRB) remains unclear, largely due to interference from low-latitude circulation systems. Using multivariate empirical orthogonal function (MVEOF) analysis and atmospheric moisture budget diagnostics, this study investigates the role of the NCCV within the 10–40-day moisture intraseasonal oscillation (MISO). We find that the NCCV alone does not directly drive rainfall over the YHRB. Its influence depends strongly on the phase of the MISO. The NCCV significantly enhances rainfall intensity over the YHRB specifically during MISO phases 4–5, when an anticyclonic moisture circulation anomaly over the western North Pacific supplies abundant moisture. During these phases, the NCCV, appearing as a cyclonic circulation anomaly to the north, interacts synergistically with the southern anticyclone. This interaction strengthens low-level wind convergence, intensifies vertical moisture advection, and favors heavy rainfall. In other MISO phases, the impact of the NCCV remains weak. Our results highlight the MISO as the primary regulator of YHRB rainfall and demonstrate that the influence of the NCCV is realized only during specific moisture-favorable dynamic windows.