Processes shaping the frontal-scale time-mean surface wind convergence patterns around the gulf stream and agulhas return current in winter

Ryusuke Masunaga*, Hisashi Nakamura, Bunmei Taguchi, Takafumi Miyasaka

*この論文の責任著者

研究成果: ジャーナルへの寄稿学術論文査読

19 被引用数 (Scopus)

抄録

High-resolution satellite observations and numerical experiments have revealed local enhancement of time-mean surface wind convergence along the axes of warm western boundary currents and divergence slightly poleward. A recent study has suggested that frequent occurrence of persistent atmospheric fronts and sea level pressure (SLP) troughs along a sea surface temperature (SST) front are responsible for shaping the frontal-scale wind convergence and divergence contrast as seen in the wintertime climatology near the Kuroshio Extension (KE). These events tend to induce surface wind convergence with moderate magnitude. Through atmospheric reanalysis with high-resolution SST, the present study reveals that, as in the vicinity of the KE, surface wind convergence with moderate magnitude and divergence with moderate-to-extreme magnitude are found to play a primary role in shaping the climatological-mean wind convergence-divergence contrasts across the SST fronts near the Gulf Stream (GS) and Agulhas Return Current (ARC) in winter. In contrast, strong-to-extreme convergence events associated with synoptic-scale atmospheric disturbances are found to yield horizontally uniform time-mean wind convergence. Furthermore, cluster analysis and case studies suggest that persistent atmospheric fronts and SLP troughs are responsible for inducing moderate wind convergence also near the GS and ARC. Thus, these features are consistent with their counterpart near the KE, but the impacts of the ARC tend to be substantially weaker, probably due to its cooler SST among other potential factors.

本文言語英語
ページ(範囲)9083-9101
ページ数19
ジャーナルJournal of Climate
33
21
DOI
出版ステータス出版済み - 2020/11/01

ASJC Scopus 主題領域

  • 大気科学

フィンガープリント

「Processes shaping the frontal-scale time-mean surface wind convergence patterns around the gulf stream and agulhas return current in winter」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル